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Moliner, Estopiñán Cristina Elia. "Valorisation of Agricultural Residues." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/68495.
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[EN] The aim of the present PhD Thesis is to define, develop and evaluate a methodology for an improved and more sustainable management of waste, in particular agricultural residues, turning them into a new source of energy and into added value products. Particular attention is paid to the use of rice straw as an energy vector and as a precursor of silica-based compounds.
The recovery of energy was carried through the gasification of biomass within a Spouted Bed Reactor. An initial definition of the main physico-chemical and thermal properties of the feed was performed. The design and operational parameters of the reactor were set according to the characteristics of the biomass. Due to the particular configuration of the reactor, its fluid dynamic properties were analysed in detail in a lab scale unit. The conditions of stability of the reactor and the prevention of segregation phenomena were studied. A scaled-up unit was used for the evaluation of the reactions of gasification of the different residues. The behaviour of the system was modelled at both fluid dynamic and thermo-chemical levels with the aid of different commercial softwares. Finally, a material valorisation was performed. The extraction of silica from the ashes resulting from the thermo-chemical process was studied. Their application as adsorbent materials for the removal of nitrates in water was discussed.<br>[ES] El objetivo de la presente tesis doctoral es definir, desarrollar y evaluar una metodología eficiente de gestión de residuos, en particular agrícolas, para convertirlos en una nueva fuente de energía y en productos de valor añadido. Se estudia con especial atención el uso de la paja de arroz como vector energético y como precursor de productos basados en sílice.
Las reacciones de recuperación energética se han llevado a cabo a través de la gasificación de la biomasa en reactores de tipo Spouted Bed. Para ello, se han definido las propiedades físico-químicas y de comportamiento térmico de los residuos estudiados. Los parámetros de diseño y operación del reactor han sido definidos de acuerdo a las características del material tratado. Debido a la particular configuración del reactor, las propiedades fluido- dinámicas del sistema se han analizado en detalle en una unidad a escala de laboratorio. En ella se han estudiado las condiciones de estabilidad del reactor y aquellas que previenen los procesos de segregación. Se ha utilizado una unidad escalada a dimensiones de planta piloto para llevar a cabo las pruebas de gasificacion de los residuos. El comportamiento del reactor se ha modelado tanto a nivel fluido dinámico como a nivel térmico mediante el uso de diversos códigos comerciales de simulación. Finalmente, se ha realizado una valorización material basada en la extracción de sílice de las cenizas resultantes del proceso de valorización térmica. Por último, se han realizado pruebas preliminares de la posible aplicación de dicha sílice en procesos de adsorción de nitratos presentes en agua.<br>[CAT] L'objectiu de la present tesi doctoral és definir, desenvolupar i evaluar una metodologia eficient de gestió de residus, en particular agrícoles, per convertir-los en una nova font d'energia i en productes de valor afegit. S'estudia amb especial atenció l'ús de la palla d'arròs com a vector energètic i com a precursor de productes basats en sílice.
Les reaccions de recuperació energètica s'han dut a terme a través de la gasificació de la biomassa en uns reactors de tipus Spouted Bed . Per això, s'han definit les propietats físico-químiques i de comportament tèrmic dels residus estudiats. Els paràmetres de disseny i operació del reactor han estat definits d'acord a les característiques del material tractat. A causa de la particular configuració del reactor, les propietats fluid - dinàmiques del sistema s'han analitzat amb detall en una unitat a escala de laboratori. S'hi han estudiat les condicions d'estabilitat del reactor i aquelles que prevenen els processos de segregació. S'ha utilitzat una unitat escalada a dimensions de planta pilot per dur a terme les proves de gasificació dels residus. El comportament del reactor s'ha modelat tant a nivell fluid dinàmic com a nivell tèrmic mitjançant l'ús de diversos codis comercials de simulació. Finalment, s'ha realitzat una valorització material basada en l'extracció de sílice de les cendres resultants del procés de valorització tèrmica. Per ùltim, s'han realitzat proves preliminars de la possible aplicació d'aquesta sílice en processos d'adsorció de nitrats presents en aigua.<br>Moliner Estopiñán, CE. (2016). Valorisation of Agricultural Residues [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/68495<br>TESIS<br>Premiado
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Robinson, Tim. "Solid state fermentation of dye-adsorbed agricultural residues." Thesis, University of Ulster, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274061.
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Dupont, Stephane. "Bound (nonextractable) residues of triazine herbicides in soybean and canola plants." Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/21091.
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Wang, Yu. "Pretreaments of Chinese Agricultural residues to increase biogas production." Thesis, Linköpings universitet, Tema vatten i natur och samhälle, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-84442.
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Development of biological conversion of lignocellulosic biomass to biogas is one approach to utilize straw comprehensively. However, high lignin contents of lignocellulosic materials results in low degradation. The main aim of this study was to investigate the appropriate pre-treatment to increase biogas production from Chinese agricultural residues. In this study, Chinese corn stalk, rice plant and wheat straw were evaluated as substrates by applying three different pre-treatments. The investigated pre-treatment were mechanical pre-treatment (cut whole straw into 1-1.5cm) combination of thermal and alkali pre-treatment (1M/L NAOH, 80℃,15 hours) and biological pre-treatment(enzymes provided by Scandinavian Biogas Fuels AB). Biogas production of these substrates was evaluated by batch digester; Sewage sludge from Nykvarn treatment plant and current digesters (Scandinavian Biogas Fuels AB )was the co-digestive substrate which seeded in batch with straw of all pre-treatments. The results indicate that at least 50% of organic contents in Chinese agricultural residues could be converted to biogas by these pre-treatments. The optimizing biogas yield is achieved from Chinese corn stalk with combination of thermal and alkali pre-treatment, Chinese rice plant and wheat straw from pre-hydrolysis pre-treatment respectively .Chinese wheat straw has the most biogas potential from combination of thermal and alkali pre-treatment.
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Pattiya, Adisak. "Catalytic pyrolysis of agricultural residues for bio-oil production." Thesis, Aston University, 2007. http://publications.aston.ac.uk/9804/.
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Agricultural residues from Thailand, namely stalk and rhizome of cassava plants, were employed as raw materials for bio-oil production via fast pyrolysis technology. There were two main objectives of this project. The first one was to determine the optimum pyrolysis temperature for maximising the organics yield and to investigate the properties of the bio-oils produced. To achieve this objective, pyrolysis experiments were conducted using a bench-scale (150 g/h) reactor system, followed by bio-oil analysis. It was found that the reactor bed temperature that could give the highest organics yield for both materials was 490±15ºC. At all temperatures studied, the rhizome gave about 2-4% higher organics yields than the stalk. The bio-oil derived from the rhizome had lower oxygen content, higher calorific value and better stability, thus indicating better quality than that produced from the stalk. The second objective was to improve the bio-oil properties in terms of heating value, viscosity and storage stability by the incorporation of catalyst into the pyrolysis process. Catalytic pyrolysis was initially performed in a micro-scale reactor to screen a large number of catalysts. Subsequently, seven catalysts were selected for experiments with larger-scale (150 g/h) pyrolysis unit. The catalysts were zeolite and related materials (ZSM-5, Al-MCM-41 and Al-MSU-F), commercial catalysts (Criterion-534 and MI-575), copper chromite and ash. Additionally, the combination of two catalysts in series was investigated. These were Criterion-534/ZSM-5 and Al-MSU-F/ZSM-5. The results showed that all catalysts could improve the bio-oils properties as they enhanced cracking and deoxygenation reactions and in some cases such as ZSM-5, Criterion-534 and Criterion-534/ZSM-5, valuable chemicals like hydrocarbons and light phenols were produced. The highest concentration of these compounds was obtained with Criterion-534/ZSM-5.
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Haag, Jennie, and Anna Landahl. "Pesticide residues in cucumbers cultivated in Bangladesh." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-234741.
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Pesticides are widely used for preventing crop losses due to pest attack. In Bangladesh, the food safety and health of farmers are being compromised as a result of poor regulation concerning usage of pesticides in food production. The aim of this study was to identify and quantify pesticides applied on cucumber crops in Bangladesh. A method for extraction and clean-up was developed to allow the quantification of four pesticides by GC-ECD in vegetable samples, specifically cucumber. The accuracy of the method was validated using recovery and its precision by studying the standard deviation and relative standard deviation. Analysis of cucumber samples obtained in the field showed no traces of the target pesticides. The results indicate that different types of chemicals are used on the examined crops. It is also believed that the growth habit of cucumber may affect the exposure to pesticides. To overcome the health hazards, restrictions regarding the types and quantities of chemicals used on the fields need to be implemented. Further studies would benefit from being executed in a controlled environment, and monitoring of which substances that are applied at which amounts.
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Sun, Xiao-Feng. "Separation and characterisation of components from agricultural residues by novel methods." Thesis, Bangor University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429863.
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Uras, Umit. "Biochar from vacuum pyrolysis of agricultural residues : characterisation and its applications." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/18011.
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Thesis (MScEng)--Stellenbosch University, 2011.<br>ENGLISH ABSTRACT: According to recent studies, biochar has the potential to improve soil fertility, mitigate climate change, reduce off-site pollution and assist in managing wastes. The application of biochar to soil is not a new concept; Amazonian dark earths are carbon-rich soils with high soil fertility that were created before 1541. Vacuum pyrolysis is a thermo-chemical conversion technique in which biomass is transformed into bio-oil, biochar and non-condensable gas. The objective of this work was to investigate the chemical and physical properties of biochar produced from vacuum pyrolysis of black wattle, vineyard annual prunings and sugar cane bagasse for their potential as soil amendment and adsorbent.
The vacuum pyrolysis of black wattle, vineyard prunings and sugar cane bagasse (pyrolysis temperature: 460°C, pressure: 8kPaabs, heating rate: 17°C/min) resulted in biochar yields of 23.5%, 31.0% and 19.7% on a weight basis, respectively. The nature of the biomass had a substantial effect on yields of the products. High ash content combined with high lignin composition led to higher biochar yields for vineyard prunings.
The highest surface acidity was observed for sugar cane bagasse (2.3 mmol/g), whereas the lowest surface acidity was observed for vineyard biochar (1.67 mmol/g). Consequently, the pH of the biochars was in the order: vineyard (10.43)> black wattle (9.74)> sugar cane bagasse (6.56). The cation exchange capacities (CEC) of biochars were 122 cmol/kg, 101 cmol/kg and 65 cmol/kg for sugar cane bagasse, black wattle and vineyard, respectively. The electrical conductivities (EC) were highly correlated with feedstock nature. The Ca and K rich vineyard biochar resulted in the highest EC (0.83 dS/m), whilst EC values of black wattle and sugar cane bagasse were 0.67 dS/m and 0.17 dS/m, respectively. Biochars contained substantial amounts of plant-available nutrients, while being low in toxic inorganic content (Pb, As, Cd). The BET surface areas of sugar cane bagasse, black wattle and vineyard were 259 mª/g, 241 mª/g and 91 mª/g, respectively.
The adsorption capacity was found to increase with increased contact time and initial solution concentration. The experimental equilibrium time were found to be 3505 min, 1350 min and 150 min for adsorption of 20 mg/L methylene blue solution for vineyard, black wattle and sugar cane bagasse, respectively. Equilibrium data were well fitted to Langmuir and Freundlich isotherms. The maximum adsorption capacities were found to be 15.15 mg/g, 14.49 mg/g and 19.23 mg/g for vineyard, black wattle and sugar cane bagasse when modelled with Langmuir isotherms. The adsorption kinetics was found to follow the pseudo-second order kinetic model.
In summary, biochar from sugar cane bagasse is a promising adsorbent for the removal of basic dyes due to its high surface area and microporous structure. This biochar can be applied to slightly acidic soils for nutrient retention and the exchange of nutrients. On the other hand, possessing high amounts of nutrients, biochars from black wattle and vineyard are potential soil amendentment agents. Biochar from black wattle is more beneficial compared to biochar from vineyard due to its higher surface area, microporosity and cation exchange capacity.<br>AFRIKAANSE OPSOMMING: Volgens onlangse studies, het houtskool die potensiaal om grond vrugbaarheid te verbeter, klimaat verandering te versag, besoedeling te verlaag en ondersteuning te verleen in die bestuur van afval. Die toevoeging van houtskool in grond is nie ‘n nuwe konsep nie; Amazone donker gronde is koolstof ryk gronde met hoë vrugbaarheid wat voor 1541 geskep is. Vakuum pirolise is ‘n termo-chemiese omskakelings tegniek waarin biomassa afgebreek word na bio-olie, houtskool en nie-kondenseerbare gasse. Die doelwit van hierdie werk was om die chemiese en fisiese eienskappe van houtskool, wat geproduseer is deur die vakuum pirolise van swart wattel, jaarlikse wingerd snoeisels, en suikerriet bagasse, vir hulle potensiaal vir grond verbetering en adsorpsie toepassings te ondersoek.
Die vakuum pirolise van swart wattel, jaarlikse wingerd snoeisels, en suikerriet bagasse (pirolise temperatuur: 460°C, druk: 8kPaabs, verhittingstempo: 17°C/min) het houtskool opbrengste van 23.5%, 31.0% en 19.7% op massa basis, respektiewelik tot gevolg. Die tipe biomassa het ‘n beduidende effek op die opbrengs van die produkte. Hoë as-inhoud, gekombineer met hoë lignien inhoud, lei tot hoër houtskool opbrengste vir wingerd snoeisels.
Die hoogste oppervlak suurheid is gevind vir suikerriet bagasse (2.3 mmol/g), terwyl die laagste waarde gevind is vir die wingerd snoeisels (1.67 mmol/g). Gevolglik, is die pH van die houtskole in die volgorde van: wingerd (10.43) > swart wattle (9.74) > suikerriet bagasse (6.56). Die katioon uitruiling vermoë (CEC) van die houtskole was 122 cmol/kg, 101 cmol/kg and 65 cmol/kg vir suikerriet bagasse, swart wattel en wingerd snoeisels respektiewelik. Die elektriese konduktiwiteite (EC) is gekorreleer met die eienskappe van die biomassas. Die Ca en K ryke wingerd snoeisel houtskool het die hoogste EC waarde (0.83 dS/m) tot gevolg, terwyl die EC waardes vir swart wattel en suikerriet bagasse bepaal is as 0.67 dS/ 0.16 dS/m respektiewelik. Die houtskole het groot hoeveelhede plant-beskikbare voedingstowwe bevat, terwyl dit laag was in toksiese anorganiese stowwe (Pb, As, Cd). Die BET oppervlak areas van suikerriet bagasse, swart wattel en wingerd snoeisels was 259 mª/g, 241 mª/g en 91 mª/g respektiewelik.
Daar is gevind dat die adsorpsie kapasiteit toeneem met toenemende kontak tyd met die aanvanklike oplossing. Die eksperimentele ewewigs tye is gevind as 350 min, 1350 min en 150 min vir die adsorpsie van ‘n 20 mg/L metileen blou oplossing vir wingerd snoeisels, swart wattel en suikerriet bagasse, respektiewelik. Die ewewigs data het die Langmuir en Freundlich isoterme goed gepas. Die maksimum adsorpsie kapasiteite is gevind as 15.15 mg/g, 14.9 mg/g en 19.23 mg/g vir wingerd snoeisels, swart wattel en suikerriet bagasse wanneer dit gemodeleer is met Langmuir isoterme. Daar is bevind dat die adsorpsie kinetika ‘n pseudo-tweede orde kintika model volg.
In opsomming, houtskool van suikerriet bagasse is ‘n veelbelowende adsorpsie middel vir die verwydering van basiese kleurstowwe, as gevolg van die hoë oppervlak area en mikroporie-struktuur van hierdie houtskool. Dié houtskool kan gebruik word op effense suur gronde vir voedingstof behoud en uitruiling. Aan die ander kant, houtskole van swart wattel en wingerd snoeisels wat hoë hoeveelhede voedingsstowwe bevat, is potensiële grond verbeterings middels. Houtskool afkomstig van swart wattel is meer voordelig as die van wingerd snoeisels, as gevolg van die hoër oppervlak area, mikroporositeit en katioon uitruilings vermoë van die swart wattel houtskool.
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Wang, Yong. "Agricultural Residues and Other Carbon-Based Resources as Feedstocks for Supercapacitor Electrodes." Diss., North Dakota State University, 2017. https://hdl.handle.net/10365/26688.
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Agricultural residues are generally considered as renewable, economical and environmental-friendly sources to produce carbon-based materials with many advanced applications. Agricultural residues and by-products generated from the agricultural industry, such as distiller's dried grains with solubles (DDGS), are produced every year on a large scale but lack of proper utilization. As a result, seeking high-value applications based on agricultural residues is essential for the promotion of the economy in agricultural states like North Dakota, USA. With the fast development of nanotechnology in recent years, carbon-based nanomaterials have attracted intense research interests in the fields of chemistry, materials science and condensed matter physics due to many unique properties (e.g., chemical and thermal stability, electrical conductivity, mechanical strength, etc.). The development of low-cost nanomaterials using agricultural residues as feedstocks can be a promising route for the sustainable development of the agricultural industry. In this dissertation, the preparation of carbon-based materials from agricultural residues is explored. Many advanced applications are investigated, especially in the field of energy storage devices. The development of porous activate carbons were investigated in detail, and their application as electrode materials of supercapacitors was demonstrated. Hydrothermal carbonization of biomass to produce carbonaceous materials was also covered in this dissertation. In addition to traditional raw materials such as cellulose produced from wood industry, novel material sources such as bacterial cellulose were used to prepare nanocomposites that can be used for the electrodes of supercapacitors. This dissertation contributes to the sustainable development of the agricultural industry in North Dakota.<br>North Dakota Corn Council North Dakota Established Program to Stimulate Competitive Research (ND EPSCoR)
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Chambers, Catherine P. "Potential impacts of transgenic crop residues on macroinvertebrate communities in agricultural streams /." Available to subscribers only, 2008. http://proquest.umi.com/pqdweb?did=1650504151&sid=1&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Tenca, A. "BIOHYDROGEN PRODUCTION FROM AGRICULTURAL AND LIVESTOCK RESIDUES WITHIN AN INTEGRATED BIOENERGY CONCEPT." Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/169992.
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Concerns about energy security, fossil fuel prices, and climate change issues, are leading to increasing renewable energy demand. Hydrogen is considered as one of the main possible energy carriers in future, due to its environmental (it can be converted to energy with the solely emission of water) and energetic (energy content of 120 MJ/kg, three times higher of the gasoline content of 44 MJ/kg) unique properties.
If hydrogen is currently being produced mainly by fossil sources, its production from renewable sources answers to the demand of more environment-friendly exploiting alternatives, possibly leading to a renewable-based hydrogen economy. Biomasses are an important renewable source ranging from energy-dedicated crops to livestock waste effluents, agro-industrial wastewaters, food-processing industry residues and organic fractions of the municipal solid waste (OFMSW). Thus the agricultural sector may acquire a renewed importance in the mid-term as a producer of energy sources for renewable biohydrogen production.
Among the biological ways to exploit biomasses for hydrogen production, this thesis focused its interest on anaerobic dark fermentation, which can simultaneously guarantee the production of an high-value product (H2) at high evolution rates and the treatment of wastes, thus transformed from an environmental pollution and greenhouse gases emissions source into a valuable resource. If on the one hand this process has lots in common with anaerobic digestion, which already is a well-established technology for treating different biomass types in real-scale plants, on the other hand it is a relatively new approach, which needs to be further studied for improving its performances and being concretely applicable.
As a matter of fact, the main disadvantage of dark fermentation is its relatively low yield, compared to other bio-hydrogen production methods, which typically are between 2.4 and 3 mol H2/mol glucose. This represents just the 20-25% of the 12 mol of H2 theoretically obtainable by glucose fermentation. Therefore, generally two different (but not mutually exclusive) options could be chosen for improving the process and making it ready for full-scale applications: the optimization of the biological, biochemical, chemical-physical operative parameters that regulate process; or the coupling of this bioprocess with other technologies capable of exploiting the organic matter not fully used by the dark fermentative approach. For example, Microbial Electrolysis Cells (MECs) are able to biologically oxidize the organic matter (from simple substrates like volatile fatty acids, lactic acid, glucose, cellulose, to actual wastewaters) releasing electrons from an anode to a cathode where potentially pure hydrogen can be formed from protons in the water.
Papers I and II basically belong to the first strategy. In Paper I indeed, two waste biomasses were co-digested: in consideration that in the Po Valley area (Italy) swine manures (SM) are yearly produced at high waste density levels and could be a cause of environmental problems, this waste was used as a co-substrate for biohydrogen production by the thermophilic fermentation of easily degradable and carbohydrate-rich materials, such as fruit and vegetable market waste (FVMW). Biohydrogen production rates and process stability were thus simultaneously maximized, thanks to the endogenous buffer capacity of manure, through the combination of a suitable composition (as FVMW/SM) of the feeding material and the hydraulic retention time (HRT) of the process. Thus, livestock manure represented not only a renewable source for supplying the production of biohydrogen, but also a source of alkali to be used for avoiding the addition of exogenous chemicals (alkali) to maintain the pH, and so the metabolic pathways and bacterial communities, into an optimal domain for biohydrogen production.
To further study and optimize the bio-H2 production in laboratory-scale processes, but also to find applicable tools for favoring dark fermentation application in full-scale biogas plants, Paper II succeeded in obtaining mixed microbial cultures from natural sources (soil-inocula and anaerobically digested materials) which reached high hydrogen yields with glucose and were used to explore the potential of bio-hydrogen production from four organic substrates of possible interest for full-scale plants (market bio-wastes, maize silage, swine manure, OFMSW). In direct prosecution of the positive co-digestion results shown in Paper I and looking for future transfer of this bioprocess technical solutions to full-scale systems, Paper II used the enriched mixed microflora for evaluating the co-fermentation of a mixture of OFMSW and swine manure in a lab-scale continuously-fed CSTR (continuously stirred tank reactor) digester. Despite the good results obtained, our study suggested that further efforts are needed for future applications of effective biohydrogen fermentation in full-scale plants.
Paper III and IV are more focused on the second scientific strategy. Paper III joins the interest toward implementation of bio-H2 in full-scale plants and the strategy of improving the overall recovery of the energy contained in the biomass associating hydrogen production to other bioprocesses. Many authors report that the two-stage anaerobic digestion (AD) process, if compared to traditional and extensively real-scale applied single-stage AD, has also other advantages, such as differentiating the biofuel production (bio-hydrogen and bio-methane), potentially reducing the plant dimensions and costs, improving the overall biogas production yields and allowing higher CH4 concentrations in the biogas produced in the second stage, thus decreasing the biogas purification costs. Therefore, a two-stage laboratory-scale CSTR anaerobic digester, fed with a mixture of agricultural and livestock residues, was monitored for a long run (approximately 700 hours) and compared to a similar one-stage reactor. This study obtained a good hydrogen yield per kg of biomass treated and partially confirmed the advantages previously illustrated, even if it reached almost the same overall energy recovery of the single stage process.
Aiming at other possible biological strategies to improve the energy and hydrogen recovery efficiency with the use of effluents from a first dark fermentative stage, a relatively new electrohydrogenesis device (MEC) was studied. Paper IV explores the rate and the yield of biogas (a mixture of H2, CH4 and CO2) produced by MEC exploiting an actual industrial wastewater with high methanol content, a compound never before reported to be used in a MEC device. The energetic recovery and treatment performance of the process was evaluated and also compared with a simulation of anaerobic digestion of the same wastewater, revealing the economical competitiveness of the MEC technology with the AD process. This leads to future research perspectives aiming to realize a laboratory-scale two-stage reactor with a MEC using the volatile-rich effluent of a first dark fermentative stage.
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Faulds, C. B. "Ferulic acid esterases from Aspergillus niger : their application in the biotransformation of agricultural residues." Thesis, University of East Anglia, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338044.
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Gronchi, Nicoletta. "Development of consolidated-bioprocessing yeasts for the second-generation bioethanol production from agricultural residues." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3424839.
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Today, the fossil materials currently represent the major share of the fuel market. In order to reduce the environmental impact resulting from the massive use of these non-renewable sources, particularly associated with the transport sector, bioethanol represents one of the most favorable, sustainable and ecological alternatives. However, the second-generation bioethanol production from waste plant biomass requires an expensive multi-step process and large dosages of commercial hydrolytic enzymes. The consolidated bioprocessing (CBP) performed by a single fermenting microbe could provide significant energy savings as well as being more cost-effective. Nevertheless, to date no naturally occurring CBP microbe has been described yet. In this study, a collection of newly isolated Saccharomyces cerevisiae strains was screened with the aim of selecting a wild type yeast with superior fermentative traits than the industrial S. cerevisiae Ethanol Red®, which is currently used at industrial scale for firstgeneration bioethanol production. The collection has been evaluated for the conversion of starchy substrates into ethanol by a simultaneous saccharification and fermentation (SSF) configuration. The S. cerevisiae L20 strain, which demonstrated the highest fermentation rate and ethanol production, was selected for a genetic engineering program in order to obtain an amylolytic yeast, for an efficient conversion of starch into ethanol. S. cerevisiae L20 and Ethanol Red® were engineered for the constitutive expression of two genes, encoding the α-amylase AmyA and the glucoamylase GlaA from Aspergillus tubingensis T8.4, in order to develop a stable recombinant strain. The well-established d-integration strategy was used to obtain recombinants at d- sequences by using homologous cassettes for AmyA and GlaA. Alongside, the innovative CRISPR / Cas9 knock-in system was used for the site-specific integration of the same genes in two selected genomic loci, namely mk114 and AD7. Both approaches were evaluated in terms of strain stability and enzymatic activity. The recombinant strains were verified for correct integration and examined for the effective secretion of amylases on agar plates containing starch. The nzymatic activity of the strains presenting the largest hydrolysis halos was quantified, and their recombinant proteins characterized by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE). The performances of the new CBP strains were then demonstrated on starchy substrates. The most promising recombinant yeast was found to be L20 dT8, co-expressing both AmyA and GlaA. This study demonstrated the superior fermenting abilities of S. cerevisiae L20 compared to Ethanol Red®, confirming its promise as a starting point for the development of a CBP yeast. Genetic editing technologies have both proven to be effective, although further efforts are needed.
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SUCIU, NICOLETA. "ASSESSING THE EFFICIENCY OF MODIFIED CLAYS FOR DECONTAMINATE AGRICULTURAL WASTE WATER BY PESTICIDE RESIDUES." Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/150174.
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Many anthropic activities, including the agricultural and food industries, give rise to environmental problems for which it is necessary to find solutions. The presence of undesirable substances in water, the soil and foodstuffs can pose a risk to the health and hygiene to humans and animals. It is therefore essential to study methods for removing pollutants from these matrices, as to make them compatible with the maintenance of healthy environmental conditions. This paper aims at verifying the possibility of using modified clays (or organic-clays) to remove contaminants from waste water coming from different areas. This work derives from the necessity to overcome the numerous, negative aspects of current techniques and offers new, effective, easy to use and economic methods.
The adsorption of the different pesticides onto micelle-clay complexes and unmodified montmorillonite clay were measured to allow the determination of the maximum pesticide quantity adsorbed in order to obtain a dose-effect relationship for practical applications. The modified clay Cloisite 20A was showed to be more efficient for use in treatment plants for the adsorption of chlorpyrifos and penconazole from aqueous solutions whereas metalaxyl is more efficiently removed by Cloisite 30B. Adsorption tests in laboratory using Cloisite 20 A were also developed for cyazofamid and cyprodinil and the results showed a high affinity of the both fungicides for the organoclay. Therefore Cloisite 20 A was show to be the most efficient organoclay from those tested in this study. This, in part, is explained by the structure of the modifier quaternary salt which contains two aliphatic chains on the structure and determinate a higher space between the layers of the montmorillonite.
Subsequently a depuration scheme was developed to test the practical applicability of the Cloisite 20A organoclay and the results showed it to be efficient for decontaminating pesticide-containing water derived from vineyards. The adsorption tests in the pilot system show a removal of three of the pesticide considered, cyazofamid, penconazole and cyprodinil, to be similar to that predicted from the adsorption tests developed in the laboratory. The recovery of the modified clay after the adsorption was shown to be dependent on the presence of surfactants in the pesticide formulation. For the adsorption test of penconazole, which contains a higher quantity of surfactants in the formulation, if compared with the formulation of cyazofamid, the recovery of Cloisite 20 A was 20% higher. For the fungicide cyprodinil, formulated with antifoaming agents, an alternative treatment of the clay-water suspension was necessary. After adsorption the suspension was passed through a compost layer which determinates the sedimentation of the clay at the compost surface.
Concerning the waste disposal, for instance the organoclay composted after the adsorption, additional treatments appear to be necessary for pesticides with moderate and high persistence in soil as penconazole and cyprodinil. The fungicide cyazofamid shows a significant decrease after 90 days, in favourable conditions of compost humidity and environment temperature.
The results of the modelling exercise shows that the FOCUS PEARL model, generally used for calculating leaching and drainage of PPP from open field cultivations to ground/surface water could be parameterised to simulate PPP emissions from greenhouses to surface water.
For the case study, weather conditions were found to have a major role on the PPP emissions from glasshouses and the open field. The more controlled climate in the greenhouse prevented a substantial precipitation excess as was observed for the open field, which had a large effect on the leaching concentrations. Furthermore, in greenhouse cultivation it was noticed that the temperature has a slightly higher influence on CC-M emissions from the greenhouse than the irrigation excess volume.
However, the main conclusion of this exercise was that there are potential PPP emissions to surface water associated with crop cultivation in greenhouses, contrary to what is stated in the European Council Regulation 1107/2009, article 3. Therefore a possible use of the outputs of this exercise is in future work to develop decontamination systems for greenhouses or for open field cultivation.
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Silveira, Henrique Leandro 1982. "Utilização do princíipio de torção por atrito para adensamento da palha de cana-de-açucar em cordas." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256922.
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Orientador: Oscar Antonio Braunbeck<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola<br>Made available in DSpace on 2018-08-15T19:34:58Z (GMT). No. of bitstreams: 1
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Previous issue date: 2010<br>Resumo: A palha da cana-de-açúcar apresenta um grande potencial para ser utilizada na co-geração de energia. Entretanto, essa energia disponível não tem sido totalmente aproveitada nas usinas, em parte devido aos custos elevados relacionados ao seu transporte do campo para a indústria, e em parte associado às deficiências no mercado de máquinas específicas para o seu recolhimento e adensamento. A palha in natura apresenta baixas densidades, o que eleva os custos de transporte e armazenamento, dado pela subutilização de carga dos caminhões e espaço físico dos pátios. O que se tem praticado nas usinas é a tentativa do uso de máquinas forrageiras e enfardadoras, que foram projetadas para a cultura do feno, resultando assim em baixos rendimentos operacionais quando utilizadas com palha de cana-de-açúcar, além de incorporar matéria mineral indesejável. Pesquisas revelaram que a corda de amarração utilizada para inibir a relaxação dos fardos prismáticos e cilíndricos provenientes das enfardadoras é responsável por 40% dos custos totais destes processos. Neste trabalho é proposto um novo princípio de adensamento para a palha de cana-de-açúcar, onde as folhas são compactadas mediante aplicação de torção visando à formação de corda contínua, que pode ser enrolada em bobinas dispensando assim os complexos sistemas de amarração das enfardadoras. A densidade teórica alcançada pela bobina formada com a corda de palha foi estimada por modelos matemáticos. Uma abrangente modelagem envolvendo as forças de compactação na corda devidas à torção é apresentada. Foram realizados experimentos em protótipo correlacionando o torque aplicado na corda com a sua densidade aparente, além de ensaios envolvendo a formação de corda contínua, visando avaliar as condições de viabilidade técnica do processo. Os resultados obtidos indicaram que foi viável tecnicamente a formação de corda contínua e estruturada a partir de folhas secas de cana-de-açúcar utilizando o princípio de torção originada por atrito; a densidade aparente da corda de palha ficou próxima das densidades aparentes dos fardos cilíndricos e prismáticos obtidos pelas enfardadoras convencionais; a demanda de torque foi menor para a corda de menor diâmetro; a densidade aparente teórica da bobina foi inferior às densidades aparentes dos fardos cilíndricos; todos os ensaios apresentaram relaxação de torque no decorrer do tempo; o princípio apresenta limitações e demanda pré-requisitos indispensáveis para o perfeito funcionamento.<br>Abstract: Sugar cane straw presents a great potential to be used in energy cogeneration. However, this potential has not been fully explored at the mills, in part due to the high costs associated with transport from field to industry, and partly linked to the market deficiencies of specific equipment for their recovery and compaction. The straw in nature presents low density, which increases the cost of transport and storage, due to the sub utilization of load capacity trucks and requirement of space in the courtyards. What has been practiced at mills are some experiments using forages and balers machines, which were designed for hay harvesting, resulting in lower operating income when used for sugar cane straw, as well as incorporating undesirable mineral matter. Research showed that the mooring rope used to inhibit the relaxation of prismatic and cylindrical bales from the balers is responsible for 40% of the total costs of these processes. This dissertation presents a proposes of a new principle for sugar cane straw compaction, where the leaves are compressed by applying torque in order to form a continuous yarn that can be wrapped into coils without complex balers mooring systems. The theoretical density achieved by the coil formed with straw rope was estimated by mathematical models. A comprehensive modeling involving the compression forces on the rope due to torsion is presented. Experiments were carried out using a prototype in order to observe the torque applied to the rope with its density correlation. Experiments involving the formation of continuous rope, to evaluate the technical feasibility of the process were also conducted. The results indicated that it was technically possible to form a continuous and structured rope from dry leaves of sugar cane using the principle of torque originate by friction; the density of straw rope was close to the apparent densities of the cylindrical and prismatic bales obtained by conventional balers; the torque demand was lower for ropes with smaller diameter; the theoretical density of the coil was less than the apparent densities of the bale; all trials showed relaxation of torque over time; the principle is limited and demand pre- established parameters for its perfect operation.<br>Mestrado<br>Maquinas Agricolas<br>Mestre em Engenharia Agrícola
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Missagia, Bruna [Verfasser], and Wolf [Akademischer Betreuer] Schluchter. "Agricultural and forestry residues for decentralized energy generation in Brazil / Bruna Missagia. Betreuer: Wolf Schluchter." Cottbus : Universitätsbibliothek der BTU Cottbus, 2012. http://d-nb.info/1023870436/34.
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Orlando, Federico. "A system dynamic model to assess exploitability of agricultural residues and effects on soil organic carbon." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17415/.
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Bio-based products are made from organic materials; the use of crop residues eliminates the competition with the food sector and lowers the costs. However, crop residues are also an important input of organic carbon in the soil, and are, therefore, important to maintain soil quality and productivity levels.
The aim of this thesis is to evaluate the variation of Soil Organic Carbon (SOC) based on the amount of agricultural residues extracted during harvesting, by use of a dynamic model. To do so, a System Dynamic model of the turnover of C in soils, based on the RothC model, was implemented. The model was used to simulate the effects of wheat straw removal from the field on the SOC in a case study based in Ravenna (Italy). A one at a time (OAT) exploratory sensitivity analysis was also conducted to study the model behaviour.
The results show an inverse linear relationship between the amount of residues extracted and the SOC at 10, 20 and 100 years of the simulation. Harvesting the crop residues can result in a decrease of the SOC of ~50%. The sensitivity analysis shows that particular care should be taken in determining the decomposition rate constant of the humus in the soil studied. An observed limitation of the RothC model is that it overestimates the SOC in semi-arid climate; however, this did not affect the results of the present case study.
Furthermore, the work underlines the role of the soil carbon/nitrogen ratio as a necessary determinant of the SOC to be maintained in soil.
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Lubwama, Michael. "Technical assessment of the functional and operational performance of a fixed bed biomass gasifier using agricultural residues." Thesis, KTH, Energy Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12824.
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<p>Currently, there is a general concern about the effects of CO2 emissions onthe atmosphere that are the major cause of the global warming phenomenon.This situation has necessitated a trend towards the reduction on thedependency on fossil fuels, a challenge facing the present generation.</p><p>Biomass gasification is the thermal chemical conversion of biomass into acombustible gaseous product (producer gas) by the supply of a gasificationagent which can be air, oxygen or steam. Biomass gasification has thepotential of contributing to the growing energy needs of the world particularlyas a renewable energy technology. The potential sustainable global suppliesof biomass encompassing sustainable recoverable residues including cropresidues, forest residues and biomass plantations is 293.3 EJ/year.</p><p>This research, therefore, has investigated the performance of a fixed bedgasifier using various agricultural residues as the feedstock. The atmosphericgasifier was operated in downdraft mode. The agricultural residuesconsidered in this research include groundnut shells, coffee husks, rice husks,bagasse and maize cobs. The proximate analyses to determine the physicalcharacteristics of the agricultural residues such as the moisture content, ashcontent, bulk density and particle size were carried out. Also, the temperaturevariations in different regions of the gasifier were investigated. Gascomposition was determined at different sampling intervals. Finally, thegasification parameters such as gas flow rate, gasification rate, turn downratio; equivalence ratio and cold gas efficiency were calculated.</p><p>The highest gasification rates were obtained in the ranges of 5.9 – 17.9 kg/hrwhile the average gas lower heating values were in the range of 3.2 –4.7MJ/Nm3. The analysis of the functional and operational performance was done for onlydowndraft mode of operation because of the non technical limitation of theflexible tube making the connection from downdraft to updraft mode ofoperation becoming rigid due to the effect of thermal stresses over the yearsand it has no replacement.</p><br>QC 20100707
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Ismayilova, Rubaba Mammad. "An analysis of producing ethanol and electric power from woody residues and agricultural crops in East Texas." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5773.
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The increasing U.S. dependence on imported oil; the contribution of fossil fuels to the
greenhouse gas emissions and the climate change issue; the current level of energy
prices and other environmental concerns have increased world interest in renewable
energy sources. Biomass is a large, diverse, readily exploitable resource. This
dissertation examines the biomass potential in Eastern Texas by examining a 44 county
region. This examination considers the potential establishment of a 100-megawatt (MW)
power plant and a 20 million gallon per year (MMGY) ethanol plant using
lignocellulosic biomass. The biomass sources considered are switchgrass, sugarcane
bagasse, and logging residues. In the case of electricity generation, co-firing scenarios
are also investigated. The research analyzes the key indicators involved with economic
costs and benefits, environmental and social impacts. The bioenergy production
possibilities considered here were biofeedstock supported electric power and cellulosic
ethanol production. The results were integrated into a comprehensive set of information
that addresses the effects of biomass energy development in the region. The analysis indicates that none of the counties in East Texas have sufficient
biomass to individually sustain either a 100% biomass fired power plant or the cellulosic
ethanol plant. Such plants would only be feasible at the regional level. Co-firing
biomass with coal, however, does provide a most attractive alternative for the study
region. The results indicate further that basing the decision solely on economics of
feedstock availability and costs would suggest that bioenergy, as a renewable energy, is
not a viable energy alternative. Accounting for some environmental and social benefits
accruing to the region from bioenergy production together with the feedstock economics,
however, suggests that government subsidies, up to the amount of accruing benefits,
could make the bioenergies an attractive business opportunity for local farmers and
investors.
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Narra, Satyanarayana [Verfasser], and Peter [Akademischer Betreuer] Ay. "Processing and refinement of biogenous residues from agricultural, industrial and biotechnological processes / Satyanarayana Narra. Betreuer: Peter Ay." Cottbus : Universitätsbibliothek der BTU Cottbus, 2014. http://d-nb.info/1046312731/34.
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Ataie, Feraidon Farahmand. "Enhancement of agricultural residue ash reactivity in concrete through the use of biofuel pretreatments." Diss., Kansas State University, 2013. http://hdl.handle.net/2097/16187.
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Doctor of Philosophy<br>Department of Civil Engineering<br>Kyle A. Riding<br>The cement industry is an important component in the quest to reduce global greenhouse gas emissions because of vast amounts of cement used annually. Incorporating supplementary cementitious materials (SCMs) into concrete is one alternative to reduce cement production and thereby reduce greenhouse gas emissions. This study investigated three types of agricultural residues, namely corn stover, wheat straw, and rice straw, in addition to bioethanol byproducts as potential resources for SCM production for concrete applications. Pretreatments, commonly used in bioethanol production, were used to improve pozzolanic reactivity of corn stover ash (CSA), wheat straw ash (WSA), and rice straw ash (RSA) in cementitious systems.
In the first part of this research, the impact of distilled water and dilute hydrochloric acid pretreatments on pozzolanic reactivity of WSA, RSA, and CSA were studied. Results showed that pretreatments, particularly dilute acid, improved pozzolanic properties of CSA, WSA, and RSA by removing potassium and phosphorous from the biomass prior to ashing. In addition, WSA and RSA were shown to have similar pozzolanic reactivity to that of silica fume.
In the second part of this study, suitability of high lignin residue (HLR), a bioethanol byproduct, for SCM production was investigated. It was shown that burning high lignin residue produces HLR ash that is very reactive in cementitious materials and can be used as a reactive SCM in concrete.
The impact of each step in the production of bioethanol on the quality of bioethanol byproduct for subsequent burning and use in concrete was also studied. Sodium hydroxide and sulfuric acid pretreatments and enzymatic hydrolysis were used. Results revealed that sodium hydroxide pretreatment of the biomass have negative impact on biomass ash properties for concrete use because sodium hydroxide pretreatment did not remove phosphorous and other crystalline phases out of the biomass. However, sulfuric acid pretreatment of biomass greatly improved ash properties. It was also shown that enzymatic hydrolysis could have beneficial impact on ash properties because, during enzymatic hydrolysis, some phosphorous was leached out of the biomass.
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Intani, Kiatkamjon [Verfasser]. "Sustainable postharvest processing of maize residues (Zea mays L.) into biochar for agricultural and environmental applications / Kiatkamjon Intani." Düren : Shaker, 2021. http://d-nb.info/1229779442/34.
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PROSPERI, PAOLO. "EVALUATION OF A REMOTE SENSING BASED METHOD FOR THE ASSESSMENT OF AGRICULTURAL CROP RESIDUES ON THE SOIL SURFACE." Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/170277.
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Increased agricultural mechanization in the recent past and susceptibility of certain soils to degradation generate widespread concern among experts on the overall environmental sustainability of some of the current agricultural practices in Europe. A number of solutions could be adopted to better preserve soil resources, some of which are already supported by the Common Agricultural Policy (CAP).
Researchers demonstrated that erosion and reduction in soil organic matter are among the most acute degradation issues in Europe and that the release of crop residues on the soil surface after harvesting can greatly reduce their incidence. The use of a permanent soil cover (e.g. by use of crop residues) is one of the three fundamental principles of Conservation Agriculture.
Quantifying the amount of crop residues on the ground is important for soil and water protection, modelling of erosion processes and legislation enforcement purposes. However, common monitoring methods based on ground sampling are expensive and likely to be impracticable on vast surfaces. Remote sensing can offer a valid alternative for monitoring.
The present research intends to contribute to the efforts towards the establishments of methods for the assessment and monitoring, through remote sensing, of the effects of conservation agriculture practices on the environment, with focus on soil resources. In this respect, the research specific objective is the evaluation of a remote sensing based method for the quantification of crop residue cover in a conservation agriculture farm in Northern Italy by use of hyperspectral satellite imagery.
Results achieved show that not only crop residues percent cover is linearly related to certain remote sensing-based indices, therefore making possible to estimate how well soil is preserved from weathering, but also that spaceborne hyperspectral sensors such as Hyperion appear to have great potentiality towards monitoring of other environmental targets due to their very high spectral and spatial resolution.
The research was deeply inspired by the outcomes of a European project (“Sustainable Agriculture and Soil Conservation through simplified cultivation techniques” - SoCo) aimed at improving protection of soil resources in the European agriculture sector through a stock taking and promotion of soil-friendly agriculture practices and systems, in particular simplified cultivation techniques, within the current legislative framework.
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Thapa, Shyam. "Optimization of Parameters for the Densification (Pelletization) of Cereal Crop Residues and Feasibility Study of Pellet Plant Development in the State of Arkansas from Economic Perspective." Thesis, Arkansas State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10640883.
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<p> Conventional cereal crop residues, namely, rice (<i> Oryza sativa</i> L.), corn (<i>Zea mays</i> L.), and wheat (<i>Triticum aestivum</i> L.) is very abundant and readily available widely. It has been a nuisance to agronomic producers to manage these immense “so-called wastes”. The Energy Independence and Security Act (EISA) promulgated by the United States and The EU’s renewable energy directive mandated the substantial incorporation of renewable energy in their final energy consumption. These led to the increase in R&D’s on biomass and bioenergy products in the United States as well. </p><p> Hammer mill grinds of different cereal crop residues, rice, wheat, and corn, sieved through 5"/64 , 1"/8 , and 5"/32 hammer mill screen sizes (details in chapter 3) are mixed with different binders namely gelatin, wheat gluten, and dry milk at 1:10, 1:15, and 1:20 proportions (Chapter 4). Applying Taguchi-Grey relational analysis for four factors with three levels each, optimal operating level for the control factors based on multi-response characteristics was determined. The multi-responses used for the study are bulk density, durability, compressive strength, and gross heating values. Binder ratio was most influential in determining pellet quality. Binder type was next influential factor. The combination of factor levels A<sub>1</sub>B<sub>1</sub>C<sub>3</sub>D<sub> 1</sub> was found to be optimal conditions for pelletization as final results were confirmed with tests. </p><p> The pelletization parameters for making better quality composite pellets were also investigated (in Chapter V). The same Taguchi –Grey relational analysis method was used for optimization. The process (material variables) parameters those are material type, particle size or grind size, binder type, and proportion of binder were closely studied using L9 Taguchi orthogonal array. Binder ratio (blending ratio) has most significant impact, and particle size (Hammer mill grind) has second greatest impact on pelleting composite wastes. Tests conducted employing optimal conditions (A3B3C2D1) has confirmed that better pellets were produced compared with the hypothesized conditions. </p><p> The cost analysis using Invest for excel was carried out in order to study the feasibility of solid biofuel project. The biomass assessment using Biopower Atlas and associated GIS tools from NREL demonstrated that the State of Arkansas has agricultural residues sufficient to support 50 kilotons and 66 kilotons biomass pellet plant. Economy of scale effect can be observed when comparing 50 kilotons and 66 kilotons pellet mill. Gelatin-wheat pellet mill at 50 kiloton and even 66 kilotons were predicted to be unprofitable at the current stage. However, analysis results showed pellet produced from pine shavings – wheat residue blends is profitable. Crop residues are promising resources due to its wide distribution and availability. It can be termed as a “Backstop resource” because it is renewable and will be economically viable option as the price of oil and gas become expensive. </p><p>
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Tsai, Ming-Yi. "The Washington orchard spray drift study : understanding the broader mechanisms of pesticide spray drift /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/8471.
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Eibisch, Nina [Verfasser]. "Physico-chemical properties and effects of biochars from hydrothermal carbonization and pyrolysis of organic residues in agricultural soils / Nina Eibisch." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2015. http://d-nb.info/1073605744/34.
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García, López Natxo. "Biomass utilization for energy purposes in Kenya : Fuel characteristics and thermochemical properties." Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-125987.
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Around forty percent of the world´s population, mostly inhabitants of countries with developing economies, rely on the traditional usage of biomass for energy purposes. The major negative consequences are environmental and health effects. Additionally, the most remarkable social consequence is rural poverty which is directly linked to lack of access to electricity. This places the questions related to biomass utilization for energy production at the core of global welfare. The present work was performed as a part of a larger research project funded by Formas and which involves Swedish and Kenyan partners. The aim of this study was to gather basic knowledge about the characteristics of relevant biomass from sub-Saharan Africa, more specifically from Kenya. Eight different types of biomass, including agroforestry trees, agricultural residues, and water hyacinth, were evaluated according to fuel characteristics and thermochemical properties. Ultimate and proximate analyses of the collected biomass were carried out, in addition to heating values analyses. Moreover, the biomass was pelletized and a thermogravimetric analysis was performed in a single pellet reactor. Finally, the composition of the residual ashes was determined. The results show that there was a large variation in the fuel characteristics and thermochemical behaviour of the studied agricultural residues and water hyacinth biomass types, whereas agroforestry trees had rather similar properties and thermochemical behaviour when combusted at the same temperature. In addition, results from the ash composition analyses showed large differences among the studied biomass types, which can be used to better predict and solve problems related to the combustion of these biomass types.
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Stökle, Katrin [Herausgeber]. "A biorefinery approach for the valorization of agricultural residues using the example of sugar extraction from Cichorium intybus var. foliosum roots." Düren : Shaker, 2021. http://d-nb.info/1240853858/34.
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Hasan, A. S. M. Monjurul. "The biogas potential from municipal waste and agricultural residues in Hazaribagh, Dhaka city, Bangladesh : - a possible strategy to improve the energy system." Thesis, Linköpings universitet, Industriell miljöteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-130692.
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Energy is considered as the foremost significant factor towards socio-economic growth. Due to the rapid growth of industrialization in Bangladesh, the need of energy is increasing day by day. Considering the environmental issues, sustainable solutions are needed to address the energy crisis. Energy generation from waste through biogas can be a good solution that can address both the energy demand as well as the waste management issue. The overall aim of this master thesis is to analyze Hazaribagh’s biogas potential from municipal waste and agricultural residues and estimate how much electricity that can be generated from the produced biogas. The feasible sources of Hazaribagh were considered in order to get the information that would be later on analyzed to estimate possible biogas production. The potential sources include wastes from two markets, six slaughterhouses, domestic wastes, three large-scale tanneries and two small scale tanneries, one poultry farm and three crop lands. The calculations made in this thesis to roughly estimate the amount of biogas and electricity from the described sources are done in a simple way, just to illustrate the potential. The result shows that the tannery waste has the highest potential followed by slaughterhouse waste. Furthermore, the calculations show that the tannery waste contributes most for electricity generation also followed by slaughterhouse waste. In order to implement biogas solutions, several actors should be involved like government, future owners, local people etc. Different tools like legislation, financial support etc. are also important for implementing the biogas solutions. In summary, there is a good potentiality of biogas production and electricity generation from municipal wastes and agricultural residues of Hazaribagh. Biogas solutions from waste and agricultural residues can be beneficial from both the energy and the waste management perspective.
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Mesa, Valenciano Martha del Carmen. "Durabilidade de compositos cimenticios com materiais lignocelulosicos." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257540.
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Orientador: Wesley Jorge Freire<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola<br>Made available in DSpace on 2018-08-03T23:55:49Z (GMT). No. of bitstreams: 1
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Previous issue date: 2004<br>Doutorado<br>Construções Rurais e Ambiencia<br>Doutor em Engenharia Agrícola
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Soares, Rodrigues Carla Ines. "EVALUATION OF DIFFERENT SOURCES OF HYDROXYL ON BIOMASS PRETREATMENT AND HYDROLYSIS." UKnowledge, 2015. http://uknowledge.uky.edu/bae_etds/28.
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Lignocellulosic biomass pretreatment is a fundamental step in the production of renewable fuels and chemicals. It is responsible for the disruption and removal of lignin and hemicellulose from the lignocellulosic matrix, improving the enzymatic hydrolysis of cellulose. Alkaline pretreatment has been shown to be successful on agricultural residues and dedicated energy crops. The objective of this study was to evaluate the pretreatment of switchgrass, wheat straw, corn stover, and miscanthus using calcium hydroxide, potassium hydroxide, and sodium hydroxide at the same hydroxyl concentration, 60% moisture content, and two temperatures for seven days. Enzymatic hydrolysis was also performed and the glucose produced measured. The composition of cellulose, hemicellulose, and lignin before and after pretreatment were quantified according to the standard procedures developed by the NREL for biomass. The hydrolysis was performed at 50°C and 150 rpm. The enzyme loading was 60 FPU/g cellulose. Overall, calcium hydroxide pretreatment resulted in the lowest delignification and structural carbohydrates after pretreatment, as well as lowest glucose yield; In addition to having a higher cost and carbon dioxide emission then sodium and potassium hydroxides. Sodium hydroxide and potassium hydroxide had similar performance in terms of composition changes due to pretreatment and glucose yield after enzymatic hydrolysis.
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Campos, Cuellar Astrid Alejandra [Verfasser], and Thomas [Akademischer Betreuer] Hirth. "Development of a process for the enhanced phosphorus recovery from the organic matrix of agricultural residues / Astrid Alejandra Campos Cuellar. Betreuer: Thomas Hirth." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2014. http://d-nb.info/1060048248/34.
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Bakhiet, Arig G. "Investigation of Agricultural Residues Gasification for Electricity Production in Sudan as an Example for Biomass Energy Utlization under Arid Climate Conditions in Developing Countries." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1211207352814-40782.
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This study examines the possibility of electricity production through gasification of agricultural residues in Sudan. The study begins in Chapter 1, by providing general contextual analysis of the energy situation (production and consumption patterns) in Sudan with specific focus on electricity. It proceeded to study the potential of Petroleum, Biomass and other renewable sources for electricity production. Dramatic increase in electricity production was found to be essential especially through decentralised power plants as the current electricity production services cover ~ 13 % of the population of Sudan. Biomass potential in Sudan justifies the use of agricultural residues as energy source; its potential was estimated by ~ 350000 TJ/a. Further, the urban centres of arid regions in western Sudan were identified as the target group for this study. In chapter 2, specific investigations for selected study area through field work using statistical tools such as questionnaires, interviews and field observation show that income is highly correlated to electricity consumption. The flat rate system did not result in higher consumption thus the assumption that this consumption will not drastically change in the next 10 years could be accepted. As orientation value for BGPP, 8000 tons of GN.S are available annually, the average electricity consumption is ~ 4 kWh/day/family while acceptable price could be 40 SDD/kWh (0.15 €). In chapter 3, literature review was carried to spot out the comparative merits of the gasification technology and the most optimum gasifying and electricity production system. As a result downdraft gasifier and ICE were suggested as suitable systems. In chapter 4, fuel properties and fuel properties of agricultural residues were studied, different samples were tested and the results were presented. The main conclusions derived were: fuel properties of agricultural residues are modifiable properties, so utlization planning is possible as for any other energy resource. In Sudan, Baggase, Groundnuts shells and Roselle stalks could be considered as possible fuels. The experimental work done in chapter 5 showed that GN.S could be gasified in down draft gasifiers, which are less costly and simpler to operate than circulating systems. Acceptable values of gas thermal properties (c.v.~ 4 MJ/Nm3, 30 % of burnable gases) at fairly continuing processes were obtained. In chapter 6, a concept for biomass power plant was drafted, the main components are: downdraft, air based gasifier connected to ICE, multi-stage gas cleaning system (cyclones, washer and filters) mechanical ash removal and semi closed water cycle. Main operation measures are: electricity is the sole product; working time is 150 day/year between mid Novembermid Mars. Environmental hazards of waste management e.g. flue gas emission and waste water management are the limiting factors. In the last part of chapter 6 an economic analysis was carried out. At a value of 3000 €/kW for the initial system and fuel price of 100000 €/year for ~6 GWh then a price of 0.23 €/kWh and a return period of 24 years could be obtained. The study concludes in chapter 7 that biomass gasification under the local conditions has its comparative merits however a high institutional support is needed at the beginning<br>Diese Studie untersucht die Möglichkeit der Elektrizitätsproduktion durch Vergasung von landwirtschaftlichen Abfällen im Sudan. Die Untersuchung beginnt im Kapitel 1 mit der Bereitstellung einer allgemeinen zusammenhängenden Analyse der Energiesituation (Produktions- und Verbrauchsmuster) im Sudan mit dem besonderen Fokus auf Elektrizität, gefolgt von einer Studie des Potentials von Petroleum, Biomasse und anderer erneuerbarer Quellen für die Produktion von Elektrizität. Eine starke Zunahme bei der Elektrizitätsproduktion wurde als nötig bewertet, da dezentrale Kraftwerke, als die gegenwärtigen Elektrizitätsproduktionsbetriebe, nur die Versorgung von 13 % der Bevölkerung im Sudan abdecken. Das geschätzte Potential der landwirtschaftlichen Abfälle liegt bei ca. 350.000 TJ/Jahre damit kommen sie als Energiequelle in Frage. Weiterhin wurden urbane Zentren der ariden Regionen in Westsudan als Zielgruppe für die Untersuchung ausgewählt. In Kapitel 2 werden detaillierte Untersuchungen für das ausgewählte Studiengebiet durch Feldstudien unter Verwendung von statistischen Werkzeugen, wie Fragebögen, Interviews und Felduntersuchungen dargestellt. Das Ergebnis zeigt, dass das Einkommen im höchsten Maße mit dem Elektrizitätsverbrauch korreliert ist. Das Flat rate System hatte keinen höheren Verbrauch zur Folge, folglich kann die Annahme akzeptiert werden, dass sich der Verbrauch in den nächsten 10 Jahren nicht drastisch ändern wird. Als Orientierungswert für Biomasse Kraftwerk: 8.000 t/Jahr Erdnussschalen sind verfügbar. Der durchschnittliche Elektrizitätsverbrauch beträgt ca. 4 kWh/Tag/Familie betrachtet für 10.000 Familien. Im Kapitel 3 wird eine Literaturrecherche für die Vergasungstechnologie durchgeführt, zum Vergleich ihrer Vorteile und zur Auswahl des optimalen Vergasungs- und Gasumwandlungssystems. Als Ergebnis wurden der Festbett-Gleichstrom-Vergaser und gas Motor als passende Systeme vorgeschlagen. In Kapitel 4 werden Brennstoff Eigenschaften von landwirtschaftlichen Abfällen untersucht, verschiedene Proben getestet und die Ergebnisse präsentiert. Die Hauptschlussfolgerung daraus ist: Brennstoff Eigenschaften von landwirtschaftlichen Abfällen sind veränderbare Eigenschaften, welche eine bessere Planung erlauben und somit ihre Verwendung favorisieren. Im Sudan können Bagasse, Erdnussschalen und Rosellenstiele als optimaler Brennstoff gelten. Die experimentelle Arbeit in Kapitel 5 zeigt, dass Erdnussschalen im 75 kW Festbett-Gleichstrom-Systemen vergast werden können, welche weniger kostenintensiv und einfach zu bedienen sind als zirkulierende Systeme. Akzeptable Werte der Gaseigenschaften (c.v. ca. 4 MJ/Nm³, 35 % von brennbaren Gasen) wurden in kontinuierlichen Prozessen erreicht. In Kapitel 6 wurde ein Konzept für Biomassekraftwerke entworfen. Deren Hauptkomponenten sind: Festbett-Gleichstrom-Vergaser in Verbindung mit ICE, mehrstufige Gasreinigungssysteme (Zyklone, Wäscher und Filter), mechanische Aschensysteme und ein teilweise geschlossener Wasserkreislauf. Hauptbetriebsmaßnahmen sind: Elektrizität als das einzige Produkt, die Arbeitszeit beträgt 150 Tage pro Jahr zwischen November und April. Umweltrisiken des Abfallmanagements z.B. Rauchgas und Abwassermanagement sind die limitierenden Faktoren. Im letzten Teil von Kapitel 6 wurde eine ökonomische Analyse durchgeführt. Ein Wert von 3000 €/kW für das Anfangssystem und ein Kraftstoffpreis von 100.000 €/Jahr für 6 GWh dann ein Preis von 0,23 €/kWh und eine Amortisationszeit von 24 Jahren können angenommen werden. Die Studie schlussfolgert, dass die Vergasung unter den Bedingungen des Studiengebietes ihre Vorteile hat, jedoch ist institutionelle Unterstützung am Anfang nötig
34
Bakhiet, Arig G. "Investigation of agricultural residues gasification for electricity production in Sudan as an example for biomass energy utilization under arid climate conditions in developing countries." Dresden TUDpress, 2008. http://d-nb.info/989198529/04.
Full text
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Bakhiet, Arig G. "Investigation of Agricultural Residues Gasification for Electricity Production in Sudan as an Example for Biomass Energy Utlization under Arid Climate Conditions in Developing Countries." Doctoral thesis, Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A23713.
Full textAbstract:
This study examines the possibility of electricity production through gasification of agricultural residues in Sudan. The study begins in Chapter 1, by providing general contextual analysis of the energy situation (production and consumption patterns) in Sudan with specific focus on electricity. It proceeded to study the potential of Petroleum, Biomass and other renewable sources for electricity production. Dramatic increase in electricity production was found to be essential especially through decentralised power plants as the current electricity production services cover ~ 13 % of the population of Sudan. Biomass potential in Sudan justifies the use of agricultural residues as energy source; its potential was estimated by ~ 350000 TJ/a. Further, the urban centres of arid regions in western Sudan were identified as the target group for this study. In chapter 2, specific investigations for selected study area through field work using statistical tools such as questionnaires, interviews and field observation show that income is highly correlated to electricity consumption. The flat rate system did not result in higher consumption thus the assumption that this consumption will not drastically change in the next 10 years could be accepted. As orientation value for BGPP, 8000 tons of GN.S are available annually, the average electricity consumption is ~ 4 kWh/day/family while acceptable price could be 40 SDD/kWh (0.15 €). In chapter 3, literature review was carried to spot out the comparative merits of the gasification technology and the most optimum gasifying and electricity production system. As a result downdraft gasifier and ICE were suggested as suitable systems. In chapter 4, fuel properties and fuel properties of agricultural residues were studied, different samples were tested and the results were presented. The main conclusions derived were: fuel properties of agricultural residues are modifiable properties, so utlization planning is possible as for any other energy resource. In Sudan, Baggase, Groundnuts shells and Roselle stalks could be considered as possible fuels. The experimental work done in chapter 5 showed that GN.S could be gasified in down draft gasifiers, which are less costly and simpler to operate than circulating systems. Acceptable values of gas thermal properties (c.v.~ 4 MJ/Nm3, 30 % of burnable gases) at fairly continuing processes were obtained. In chapter 6, a concept for biomass power plant was drafted, the main components are: downdraft, air based gasifier connected to ICE, multi-stage gas cleaning system (cyclones, washer and filters) mechanical ash removal and semi closed water cycle. Main operation measures are: electricity is the sole product; working time is 150 day/year between mid Novembermid Mars. Environmental hazards of waste management e.g. flue gas emission and waste water management are the limiting factors. In the last part of chapter 6 an economic analysis was carried out. At a value of 3000 €/kW for the initial system and fuel price of 100000 €/year for ~6 GWh then a price of 0.23 €/kWh and a return period of 24 years could be obtained. The study concludes in chapter 7 that biomass gasification under the local conditions has its comparative merits however a high institutional support is needed at the beginning.<br>Diese Studie untersucht die Möglichkeit der Elektrizitätsproduktion durch Vergasung von landwirtschaftlichen Abfällen im Sudan. Die Untersuchung beginnt im Kapitel 1 mit der Bereitstellung einer allgemeinen zusammenhängenden Analyse der Energiesituation (Produktions- und Verbrauchsmuster) im Sudan mit dem besonderen Fokus auf Elektrizität, gefolgt von einer Studie des Potentials von Petroleum, Biomasse und anderer erneuerbarer Quellen für die Produktion von Elektrizität. Eine starke Zunahme bei der Elektrizitätsproduktion wurde als nötig bewertet, da dezentrale Kraftwerke, als die gegenwärtigen Elektrizitätsproduktionsbetriebe, nur die Versorgung von 13 % der Bevölkerung im Sudan abdecken. Das geschätzte Potential der landwirtschaftlichen Abfälle liegt bei ca. 350.000 TJ/Jahre damit kommen sie als Energiequelle in Frage. Weiterhin wurden urbane Zentren der ariden Regionen in Westsudan als Zielgruppe für die Untersuchung ausgewählt. In Kapitel 2 werden detaillierte Untersuchungen für das ausgewählte Studiengebiet durch Feldstudien unter Verwendung von statistischen Werkzeugen, wie Fragebögen, Interviews und Felduntersuchungen dargestellt. Das Ergebnis zeigt, dass das Einkommen im höchsten Maße mit dem Elektrizitätsverbrauch korreliert ist. Das Flat rate System hatte keinen höheren Verbrauch zur Folge, folglich kann die Annahme akzeptiert werden, dass sich der Verbrauch in den nächsten 10 Jahren nicht drastisch ändern wird. Als Orientierungswert für Biomasse Kraftwerk: 8.000 t/Jahr Erdnussschalen sind verfügbar. Der durchschnittliche Elektrizitätsverbrauch beträgt ca. 4 kWh/Tag/Familie betrachtet für 10.000 Familien. Im Kapitel 3 wird eine Literaturrecherche für die Vergasungstechnologie durchgeführt, zum Vergleich ihrer Vorteile und zur Auswahl des optimalen Vergasungs- und Gasumwandlungssystems. Als Ergebnis wurden der Festbett-Gleichstrom-Vergaser und gas Motor als passende Systeme vorgeschlagen. In Kapitel 4 werden Brennstoff Eigenschaften von landwirtschaftlichen Abfällen untersucht, verschiedene Proben getestet und die Ergebnisse präsentiert. Die Hauptschlussfolgerung daraus ist: Brennstoff Eigenschaften von landwirtschaftlichen Abfällen sind veränderbare Eigenschaften, welche eine bessere Planung erlauben und somit ihre Verwendung favorisieren. Im Sudan können Bagasse, Erdnussschalen und Rosellenstiele als optimaler Brennstoff gelten. Die experimentelle Arbeit in Kapitel 5 zeigt, dass Erdnussschalen im 75 kW Festbett-Gleichstrom-Systemen vergast werden können, welche weniger kostenintensiv und einfach zu bedienen sind als zirkulierende Systeme. Akzeptable Werte der Gaseigenschaften (c.v. ca. 4 MJ/Nm³, 35 % von brennbaren Gasen) wurden in kontinuierlichen Prozessen erreicht. In Kapitel 6 wurde ein Konzept für Biomassekraftwerke entworfen. Deren Hauptkomponenten sind: Festbett-Gleichstrom-Vergaser in Verbindung mit ICE, mehrstufige Gasreinigungssysteme (Zyklone, Wäscher und Filter), mechanische Aschensysteme und ein teilweise geschlossener Wasserkreislauf. Hauptbetriebsmaßnahmen sind: Elektrizität als das einzige Produkt, die Arbeitszeit beträgt 150 Tage pro Jahr zwischen November und April. Umweltrisiken des Abfallmanagements z.B. Rauchgas und Abwassermanagement sind die limitierenden Faktoren. Im letzten Teil von Kapitel 6 wurde eine ökonomische Analyse durchgeführt. Ein Wert von 3000 €/kW für das Anfangssystem und ein Kraftstoffpreis von 100.000 €/Jahr für 6 GWh dann ein Preis von 0,23 €/kWh und eine Amortisationszeit von 24 Jahren können angenommen werden. Die Studie schlussfolgert, dass die Vergasung unter den Bedingungen des Studiengebietes ihre Vorteile hat, jedoch ist institutionelle Unterstützung am Anfang nötig.
36
Favaro, Lorenzo. "Selection and genetic improvement of microorganisms for second generation bioethanol." Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3426951.
Full textAbstract:
Bioethanol produced from biomass is considered an interesting second generation biofuel. To date a cost-effective method for converting biomass into ethanol has not been developed. Consolidated BioProcessing is one of the most attractive strategies aiming to obtain ethanol from biomass by a single microbial phase.
In this study, the selection and genetic improvement of microbial strains started in order to develop a microbe for the one-step bioconversion of biomass into ethanol.
New efficient cellulolytic microrganisms were isolated and genetically identified. Their hydrolytic activities were remarkable and few strains may have also improvable ethanol production properties.
Four hundred wild type yeasts, having optimal fermentative performance, were evaluated for their extracellular enzymatic activities. The yeasts showed interesting hydrolytic activity on pectin, cellulose and starch. In particular, one non-Saccharomyces strain produced efficient cellulolytic enzymes and thirteen S. cerevisiae strains, able to use starch as the sole carbon source, were selected. Extensive biochemical, physiological and genetic studies on their potentially amylolytic enzyme(s) were performed to look into this possible new starch-hydrolytic mechanism.
In addition, wheat bran was used, as a model substrate of starchy and cellulosic residues, to design a Separated Hydrolysis and Fermentation (SHF) system aiming at low-cost pre-treatments and high yields. The downstream fermentation, carried out with two Saccharomyces sp. yeasts, resulted in interesting ethanol yields.
A metabolic engineering program was conducted in order to obtain an efficient amylolytic yeast for large scale ethanol production. Wild type S. cerevisiae strains with selected industrial traits were engineered to express a fungal codon-optimised glucoamylase. The stable recombinants produced ethanol from soluble and raw starch and could be considered promising for the Consolidated Bioprocessing of starchy industrial residues.
On the basis of the preliminary results obtained, this multi-disciplinary work represents a first step towards the development of microbes for the single-step conversion of biomass into ethanol.<br>Il bioetanolo di seconda generazione rappresenta una delle alternative più promettenti tra i biocarburanti. Dal punto di vista biotecnologico, la definizione di un processo economicamente sostenibile per la produzione di bioetanolo da biomassa lignocellulosica è ancora lontana. Lo sviluppo di un microrganismo CBP (Consolidated BioProcessing) capace di idrolizzare i polimeri complessi della biomassa e di convertirli efficacemente in etanolo è una delle strategie più interessanti nel panorama scientifico internazionale.
Questo studio ha avviato un programma di selezione e miglioramento genetico di ceppi microbici finalizzato allo sviluppo di un microrganismo adatto alla produzione CBP di bioetanolo da biomassa.
Numerosi ceppi microbici cellulosolitici sono stati isolati ed identificati. Le loro attività idrolitiche sono elevate e alcuni isolati hanno dimostrato potenziali capacità fermentative. Inoltre, quattrocento ceppi di lievito wild type sono stati caratterizzati per la loro capacità di produrre enzimi extracellulari. Alcuni ceppi hanno presentato interessanti attività idrolitiche a carico di pectina, cellulosa ed amido. In particolare, un lievito non-Saccharomyces si è distinto per la produzione di efficienti cellulasi e tredici isolati di S. cerevisiae sono stati selezionati per la capacità di utilizzare amido solubile come unica fonte di carbonio.
Lo studio ha inoltre sviluppato un sistema SHF (Separated Hydrolysis and Fermentation) per la conversione in etanolo di crusca di grano, scelta come substrato modello di residui agro-industriali a basso costo. Le rese in etanolo, ottenute mediante due ceppi di Saccharomyces sp. opportunamente selezionati, sono risultate promettenti.
Un programma di ingenieria genetica ha consentito di ottenere alcuni ceppi mutanti per l'integrazione cromosomica multipla di un gene sintetico codificante per una glucoamilasi fungina. I ceppi ricombinanti, capaci di produrre etanolo da amido grezzo, potrebbero essere impiegati efficacemente in processi CBP a partire da residui industriali amidacei.
In base ai risultati preliminari finora conseguiti, questo studio rappresenta un primo passo verso lo sviluppo di microrganismi idonei alla conversione one-step di biomassa in etanolo.
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Sathanantham, Preethi. "Impact of Mutations of Targeted Serine, Histidine, and Glutamine Residues in Citrus paradisi Flavonol Specific Glucosyltransferase Activity." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etd/2560.
Full textAbstract:
A flavonol specific glucosyltransferase cloned from Citrus paradisi has strict substrate and regio-specificity (Cp3OGT). The amino acid sequence of Cp3OGT was aligned with sequences of an anthocyanidin UDP- dependant glucosyltransferase (UGT) from Clitorea ternatea and a UGT from Vitis vinifera that can glucosylate both flavonols and anthocyanidins. Using homology modeling to identify candidate regions followed by site directed mutagenesis, three double mutations were constructed and biochemically characterized. S20G+T21S mutant protein retained activity with flavonols similar to the wildtype Cp3OGT but the mutant had optimum activity at 60°C and broadened substrate acceptance to include the flavanone naringenin. S290C+S319A mutant protein retained 40% activity with quercetin relative to WT, and had an optimum pH shift. H154Y+Q87I mutant protein was only 10% active with quercetin relative to WT. Docking analysis revealed that H154, Q87 and S20 could be involved in orienting the acceptor molecules within the acceptor binding site whereas S319 and S290 residues are involved in maintaining the active site conformation.
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Zucco, Loris Lodir. "Avaliação do comportamento fisico-quimico-mecanico de misturas cimento-cinza-casca de arroz por meio de corpos-de-prova cilindricos e placas prensadas." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257028.
Full textAbstract:
Orientador: Antonio Ludovico Beraldo<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola<br>Made available in DSpace on 2018-08-09T11:32:00Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007<br>Resumo: A reciclagem pode ser considerada uma ferramenta adequada para minimizar o impacto humano causado ao meio ambiente, o que aponta para o aproveitamento de resíduos agrícolas na obtenção de materia is para construções rurais, como uma forma alternativa de seqüestro ou da não emissão de carbono. O aproveitamento racional dos resíduos ainda é um problema não solucionado e uma parte substancial dos resíduos é desperdiçada, ou contamina o meio ambiente. No entanto, agregados de origem vegetal podem ser empregados na fabricação de artefatos leves de cimento, na busca de materiais de comportamento diferenciado em termos de isolamento térmico e acústico e de resistência às cargas dinâmicas. Esse trabalho de pesquisa, baseado em estudos anteriores envolvendo o aproveitamento da casca de arroz (CASCA), objetivou a redução no consumo de cimento através da incorporação de maior quantidade de material, a casca de arroz queimada em condições especiais, resultante de processo industrial (CINZA). Os percentuais de adição de casca e de cinza, variaram em função do tipo de mistura (pasta ou compósito). Assim, as diferentes misturas cimento-cinzacasca obtidas foram agrupadas em FASES, de acordo com o tipo de mistura (Pasta ou Compósito), a quantidade de casca (7,5% nas Fases I e II; variável nas Fases III e IV) e a quantidade de cinza (0%, 5%, 20% e 35%, na fase I e de 0%, 20% e 35%, nas demais fases). Por ser um material biológico a casca de arroz apresentou comportamento físico-químicomecânico variável, com síntese apresentada ao final de cada fase, em função do grande volume de informação (interação entre os fatores CASCA e CINZA). São apresentadas avaliações do comportamento químico, físico e mecânico das misturas à base de cimento, com incorporação de casca de arroz e/ou cinza da casca de arroz. As avaliações evidenciaram através do comportamento químico das misturas, o efeito negativo dos extrativos da casca de arroz (lavada em solução de cal) sobre as reações químicas do cimento (curva de hidratação), bem como sua redução pela adição de cinza, independentemente da distribuição em tamanho das partículas de casca. Atribuiu-se ao alto teor de carbono (98%) da cinza, a melhoria no comportamento químico das misturas. As reduções observadas em alguns parâmetros químicos, com a adição de cinza, está associada ao aumento de massa no sistema. A avaliação do comportamento físico-mecânico das misturas evidenciou que a adição de casca promoveu um aumento na resistência em tração por compressão diametral e redução na resistência em compressão simples. A adição de cinza promoveu aumento nestas resistências. A avaliação das placas prensadas evidenciou a ausência de diferença significativa entre as misturas, fato este também constatado na fase III, de modo que a adição de cinza não afetou de forma significativa a resistência mecânica, o que sugere a mistura 10 mm-35% como sendo a mais adequada para a produção de compósitos cimento-cinza-casca, com redução no consumo de cimento em cerca de 25%. Destaca-se que a mistura 10 mm-35% apresentou a maior capacidade de confinamento (ou de não emissão) de carbono. Sua capacidade de confinar foi estimada em cerca de 1,9 toneladas de CO2 por tonelada de cimento consumido no processo de fabricação do compósito, o que seria liberado para a atmosfera, quando da queima da casca de arroz no uso ou descarte inadequados.
Palavras-chaves: calorimetria; casca de arroz; cimento; cinza; compósito<br>Abstract: The recycling is an effective tool to minimize environmental impact that is caused by human civilization. The utilization agricultural residual for rural construction is an efficient way for retain or reduce carbon emission to the atmosphere. However, the present-day techno logy is not enough to be a satisfactory level. A part of the residue is not consumed, and the rejected substances are causing environmental pollution. However, the vegetable aggregates can be employed to lightweight cement artifacts production, which is applied to thermal and acoustic isolators. This work look for a method for light artifacts production with minor cement consumption and larger rice husk (HUSK) consumption, with the help of the rice husk burned by a special industrial process (ASH). The ash and rice husk addition percentages had varied in function of the type of mixture (paste or composite). The different gotten mixtures cement-ash-rice husk been grouped in PHASES, in accordance with the type of mixture (Paste or Composite), the amount of rice husk (7.5% in Phases I and II; variable in Phases III and IV) and the amount of ash (0%, 5%, 20% and 35%, in phase I and of 0%, 20% and 35%, in the too much phases). For a biological material, the rice husk presented behavior changeable physic-chemistry-mechanic. A analyze synthesis is presented on the end each phase; this is necessary of the great volume of the information (interaction between the factors HUSK and ASH). Evaluations of the chemical, physical and mechanical behavior of cementash- rice husk mixtures are presented. The evaluations had evidenced through the chemical behavior of the mixtures, the negative effect of the extractives of the rice husk (Washed in Lime Solution) on the chemical reactions of the cement - hydration curve (temperature against time), the its reduction with the ash addition, independently of the particles size range. The high carbon content (98%) of the ash attributed the improvement to the chemical behavior of the mixtures. The reductions observed in some chemical parameters, with the ash addition, are associated with the increase of mass in the system. The behavior physical-mechanical evaluation of the mixtures evidenced that the rice husk addition increase the resistance in Brazilian test, with reduction in the resistance in simple compression. The ash addition promoted increase in this resistance. The evaluation of the board manufacturing evidenced an absence of significant difference between the mixtures, fact also evidenced in phase III. The ash addition not is significant affect in the mechanical resistance properties. The mixture 10 mm-35% proposed from at the production of composite, have reduction in the cement consumption in about 25%. In detach for 10 mm-35% mixture, presented the higher capacity of retain or reduce carbon dioxide emission. The capacity of to confine was estimated to in about 1.9 tons of CO2 for each ton of cement consumed in the process of manufacture of the composite, what would be emitted for the atmosphere, when of the burning of the rice husk, on the use or in the inadequate deposit. Keyywords: ash; calorimetric, cement; composite; rice husk<br>Doutorado<br>Construções Rurais e Ambiencia<br>Doutor em Engenharia Agrícola
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Có, Júnior Caramo [UNESP]. "Fertilização com lodo de esgoto e vinhaça e influência nas frações de nitrogênio do caldo e qualidade da cana-de-açúcar." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/96923.
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cojunior_c_me_jabo.pdf: 361271 bytes, checksum: 9ff1fcdd435782a04d63112733b2d4f3 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>O objetivo deste trabalho foi avaliar os efeitos residuais da aplicação, de diferentes resíduos e doses, sobre as frações de nitrogênio em caldo da cana nas diferentes partes do colmo e na qualidade da cana de (cultivar SP 81–3250). O delineamento experimental foi em blocos casualizados com 13 tratamentos e 3 repetições, analisado em esquema fatorial 3 x 2 x 2 mais um tratamento adicional. Os tratamentos testados foram resultantes de três combinações de dois tipos de resíduos (lodo de esgoto; vinhaça; lodo de esgoto + vinhaça) com dois modos de aplicação (ao lado da linha de cana e em área total) e com duas doses (100 e 200 %) e mais um tratamento testemunha adicional. As variáveis analisadas foram: Nitrogênio Total, Nitrogênio Amoniacal, Nitrogênio Não Protéico, Nitrogênio Amínico e Nitrogênio Protéico. A vinhaça proporcionou os maiores teores de Nitrogênio em todas as frações analisadas. As aplicações dos resíduos com a dose aumentada em 100% demonstram a superioridade nas variáveis determinadas. Apenas não aumentou a fração do Nitrogênio Protéico. Nas variáveis analisadas não proporcionaram alterações na porcentagem de nitrogênio nas folhas, palmito e terço inferior dos colmos. No terço médio dos colmos, a aplicação de vinhaça resultou em maior porcentagem de nitrogênio. Entretanto, o uso da dose em dobro proporcionou maior porcentagem de nitrogênio no terço médio e inferior do colmo. Os resíduos podem substituir a fertilização mineral sem que prejuízos ou vantagens sejam auferidos à qualidade da matéria prima.<br>The objective of this work was to evaluate the residual effect of residues applied during four years in distinct forms and doses, upon nitrogen fractions of sugar cane juice in deferent parts of stalk and quality of the sugar cane (4th Raton cane - cultivar SP 81–3250. The experimental design was randomized bocks with 13 treatments and 3 replications. To statistical analyze the results were organized in a 3x2x2 factorial scheme plus an additional treatment control. The treatments were the result of three combinations between 2 residues (sewage sludge, vinasse, sewage sludge + vinasse), applied in 2 different ways (close to the sugar cane line and spread in total area), in 2 doses (100 and 200%) plus a control treatment. The experimental design was randomized bocks with 13 treatments and 3 replications. The following parameters were analyzed: Total Nitrogen, Ammoniac Nitrogen, Non Protein Nitrogen, “Amino” Nitrogen and Protein Nitrogen juice contents. The vinasse provides the higher contents of nitrogen in whole fractions analyzed. The doses higher than 100% shown highest values for all parameters, except for protein nitrogen. All analyzed factors did not affect the leaf, heart and top stalk nitrogen contents. In middle part of stalks, vinasse application resulted to higher nitrogen contents than another parts. Although, when the double dose was used, higher nitrogen content at middle and lower parts of stalks were observed. The residues can substitute mineral fertilization without changes in raw material quality.
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Có, Júnior Caramo. "Fertilização com lodo de esgoto e vinhaça e influência nas frações de nitrogênio do caldo e qualidade da cana-de-açúcar /." Jaboticabal : [s.n.], 2007. http://hdl.handle.net/11449/96923.
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Orientador: Marcos Omir Marques<br>Banca: Ailto Antonio Casagrande<br>Banca: Carlos Alberto Mathias Azania<br>Resumo: O objetivo deste trabalho foi avaliar os efeitos residuais da aplicação, de diferentes resíduos e doses, sobre as frações de nitrogênio em caldo da cana nas diferentes partes do colmo e na qualidade da cana de (cultivar SP 81-3250). O delineamento experimental foi em blocos casualizados com 13 tratamentos e 3 repetições, analisado em esquema fatorial 3 x 2 x 2 mais um tratamento adicional. Os tratamentos testados foram resultantes de três combinações de dois tipos de resíduos (lodo de esgoto; vinhaça; lodo de esgoto + vinhaça) com dois modos de aplicação (ao lado da linha de cana e em área total) e com duas doses (100 e 200 %) e mais um tratamento testemunha adicional. As variáveis analisadas foram: Nitrogênio Total, Nitrogênio Amoniacal, Nitrogênio Não Protéico, Nitrogênio Amínico e Nitrogênio Protéico. A vinhaça proporcionou os maiores teores de Nitrogênio em todas as frações analisadas. As aplicações dos resíduos com a dose aumentada em 100% demonstram a superioridade nas variáveis determinadas. Apenas não aumentou a fração do Nitrogênio Protéico. Nas variáveis analisadas não proporcionaram alterações na porcentagem de nitrogênio nas folhas, palmito e terço inferior dos colmos. No terço médio dos colmos, a aplicação de vinhaça resultou em maior porcentagem de nitrogênio. Entretanto, o uso da dose em dobro proporcionou maior porcentagem de nitrogênio no terço médio e inferior do colmo. Os resíduos podem substituir a fertilização mineral sem que prejuízos ou vantagens sejam auferidos à qualidade da matéria prima.<br>Abstract: The objective of this work was to evaluate the residual effect of residues applied during four years in distinct forms and doses, upon nitrogen fractions of sugar cane juice in deferent parts of stalk and quality of the sugar cane (4th Raton cane - cultivar SP 81-3250. The experimental design was randomized bocks with 13 treatments and 3 replications. To statistical analyze the results were organized in a 3x2x2 factorial scheme plus an additional treatment control. The treatments were the result of three combinations between 2 residues (sewage sludge, vinasse, sewage sludge + vinasse), applied in 2 different ways (close to the sugar cane line and spread in total area), in 2 doses (100 and 200%) plus a control treatment. The experimental design was randomized bocks with 13 treatments and 3 replications. The following parameters were analyzed: Total Nitrogen, Ammoniac Nitrogen, Non Protein Nitrogen, "Amino" Nitrogen and Protein Nitrogen juice contents. The vinasse provides the higher contents of nitrogen in whole fractions analyzed. The doses higher than 100% shown highest values for all parameters, except for protein nitrogen. All analyzed factors did not affect the leaf, heart and top stalk nitrogen contents. In middle part of stalks, vinasse application resulted to higher nitrogen contents than another parts. Although, when the double dose was used, higher nitrogen content at middle and lower parts of stalks were observed. The residues can substitute mineral fertilization without changes in raw material quality.<br>Mestre
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Eliasson, Jenny, and Viktor Carlsson. "Agricultural waste and wood waste for pyrolysis and biochar : An assessment for Rwanda." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-283611.
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A high priority in order to combat climate change is disposal of waste. In low-income countries, a large portion of biomass residues generated in the forestry, agricultural and industrial sectors could be usable, instead of being seen as waste. For instance, it could be converted into biochar, which is proven to have many environmental benefits. In Rwanda, the agricultural sector employs 80% of the population and accounts for 35% of GDP. This sector, together with later refinement of crops and forestry production, cause large amounts of residue that many times is considered as waste. In this report, a literature study was conducted to evaluate possible biochar production from agricultural and wood wastes in Rwanda. Characteristics that determine if a biomass could be suitable for a biochar production were identified as C, H, O, N, S, hemicellulose, cellulose, lignin, ash and moisture content, residue-to-product ratio, and low heating value. These characteristics were assessed for the chosen Rwandan agricultural and wood wastes, by compiling values from published reports. The result shows that there are large volumes of residues that have potential for biochar production instead of being seen as waste in Rwanda. Biochar production from these wastes could enable environmental benefits for Rwanda, although further investigation of each single biomass could be needed in order to see if it is practically, technically and financially possible to do in reality.<br>För att bekämpa klimatförändringen är avfallshantering en hög prioritet. I låginkomstländer kan en stor andel av biomassarester som genereras i skogsbruk, jordbruks- och industrisektorer vara användbara, istället för att ses som avfall. Till exempel skulle det kunna omvandlas till biokol, som har visats sig ha många miljömässiga fördelar. I Rwanda arbetar 80% av befolkningen inom jordbrukssektorn och den står för 35% av BNP. Denna sektor, tillsammans med förädling av grödor och skogsbruksproduktion, orsakar stora mängder rester som många gånger betraktas som avfall. I denna rapport genomfördes en litteraturstudie för att utvärdera möjlig produktion av biokol från jordbruks- och träavfall i Rwanda. Egenskaper som avgör om en biomassa kan vara lämplig för en biokolsproduktion identifierades som C-, H-, O-, N-, S-, hemicellulosa-, cellulosa-, lignin-, ask- och fukthalt, samt andel avfall som uppstår i förhållande till färdig produkt och värmevärde. Dessa egenskaper utvärderades för det valda jordbruks- och träavfallet genom att sammanställa värden från publicerade rapporter. Resultatet visar att det finns stora volymer rester som har potential för biokolsproduktion istället för att ses som avfall i Rwanda. En biokolsproduktion från dessa avfall skulle kunna ge miljömässiga fördelar för Rwanda, även om ytterligare undersökning av varje enskild biomassa skulle behövas för att se om det är praktiskt, tekniskt och ekonomiskt möjligt att genomföra i verkligheten.
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Arranz, Piera Pol. "Prospects of distributed electricity generation and services based on small scale biomass systems in Ghana." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/664278.
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Access to energy is crucial to human welfare; no residential, commercial or industrial activity can be conceived without energy supply. At the same time, current dependence on fossil fuels and their negative effects on global climate claim for urgent alternatives. The situation in Sub-Saharan Africa is poignant: over half of the population, mainly in rural areas, live without access to electricity services. Crop residues from farming communities in those areas are unused; while technology for electricity production from agricultural biomass is progressing, managing decentralised rural electricity projects is still a challenge, especially in developing countries like Ghana, given the variety and complexity of the factors conditioning biomass to energy supply chains. Such complexity has been previously formulated in academic exercises, but with limited practical applicability for energy planners, practitioners and investors.
This research has deployed a holistic approach to biomass-to-energy planning, yet flexible to adapt to different regulatory scenarios and energy supply configurations. A qualitative framework has been developed, taking into consideration four critical components: social development, organisational/institutional, technical, and financial, with their respective metrics. Then, the framework has been applied to three real case study configurations in Ghana, involving primary data collection, sustainability modelling and discussion of the techno-economic feasibility results with policy makers and practitioners.
The first configuration consists in decentralised power generation using crop residues from clustered smallholder farms in 14 districts in Ghana; the number of clustered farms, reference residue yields, and residue densities are determined to assess the distances within which it would be feasible to supply feedstock to biomass power plants. The findings show that a minimum of 22 to 54 larger (10 ha) farms would need to be clustered to enable an economically viable biomass supply to a 1000 kWe plant. Financial analyses indicate that such investment would not be viable under the current renewable feed-in-tariff rates in Ghana; increased tariff by 25% or subsidies from a minimum 30% of investment cost are needed to ensure viability using internal rate of return as an indicator. Carbon finance options are also discussed.
The second configuration focuses on co- and tri-generation from clustered crop residues. Techno-economic results show that 600 kW and 1 MW biomass fuelled plants to generate power, heating (for cassava or maize drying) and cooling (to refrigerate tomatoes) are feasible, considering a minimum 20% yearly profit for investors’ equity. Additional income between 29 and 64 US $/tonne of crop residue would be possible for farmers if a minimum of 60% of the heat produced can be traded. The consideration of carbon financing under the most common traded prices has little impact on the project results; if more favourable schemes (like the Swedish carbon tax) are considered, the viability of co- and tri-generation plants run on agro residue can be possible even with a low level of residual heat sales.
The third configuration analyses minigrid electricity generation and services based on biomass gasification in five Ghanaian communities. Results show that the projected electricity demand compares favourably with the potential supply from available crop residues. Project financing via 100% private funding would not be viable under current national uniform tariffs; however, by applying an end-user tariff equal to the current expenditure on electricity-equivalent uses in the communities, a subsidy of about 35% on initial investment would enable a private entrepreneur an internal rate of return of 15%, whereas a 60% subsidy could enable internal rate of return of 25%.
The outcomes of this research have triggered the interest of Ghanaian and international policy makers, developers and private investors.<br>L'accés a l'energia és crucial per al benestar humà, no es pot concebre cap activitat residencial, comercial o industrial sense subministrament d'energia. Alhora, la dependència actual dels combustibles fòssils i els seus efectes negatius sobre el clima global reclamen alternatives urgents. La situació a l'Àfrica Subsahariana és punyent: més de la meitat de la població, principalment rural, viu sense accés a serveis elèctrics. Tanmateix, en aquestes zones abunden les restes agrícoles. Tot i que la tecnologia per a la producció d'electricitat a partir de biomassa agrícola avança, la promoció de l’electrificació rural descentralitzada continua sent un repte, especialment en països en desenvolupament com Ghana, atesa la varietat i la complexitat de factors que condicionen l’aprofitament energètic de la biomassa. Aquesta complexitat s'ha tractat en exercicis acadèmics, però amb poca aplicabilitat pràctica per a planificadors d'energia, promotors i inversors. A fi de contribuir a una millor planificació i presa de decisions, aquesta Tesi desplega un marc integral d’anàlisi tenint en compte quatre components (desenvolupament social, organitzatiu/institucional, tècnic, i financer), flexible per adaptar-se a diferents configuracions de subministrament d'energia i escenaris reguladors. Aquest marc s'ha aplicat a tres casos reals a Ghana, recollint dades de camp, modelitzant la viabilitat tecno-econòmica i debatent els resultats amb promotors públics i privats. La primera configuració consisteix en la generació elèctrica a partir de restes agrícoles de petites plantacions rurals, en 14 districtes a Ghana, on s?ha determinat la biomassa disponible i la seva localització per calcular les distàncies màximes que permetrien la rendibilitat de petites centrals elèctriques. Els resultats indiquen que un mínim de 22 a 54 plantacions (de 10 ha. cadascuna) haurien d'agrupar-se per permetre un subministrament de biomassa econòmicament viable a una planta de 1000 kWe. Financerament aquesta inversió no seria viable amb les tarifes actuals d’injecció a xarxa; un increment d’aquesta tarifa en un 25%, o bé una subvenció mínima del 30% del cost d'inversió són necessàries per garantir la viabilitat. La segona configuració se centra en la co- i la tri-generació a partir de restes agrícoles. Els resultats de l’anàlisi tècnic-econòmica mostren que centrals de 600 kW i 1 MW per autogenerar electricitat, calor (per assecar mandioca o de blat de moro) i fred (per refrigerar tomàquets) són factibles, fins i tot aportant un retorn anual mínim del 20% per a inversors externs. A més de l’electricitat, en cas de poder vendre com a mínim un 60% de la calor produïda, es podria pagar entre 29 i 64 USD per tona de biomassa. La consideració de bons de carboni a preus habituals de mercat internacional té poc impacte en els resultats del projecte; si es consideren esquemes més favorables (com els bons de carboni a Suècia), la viabilitat de les plantes de co-i tri-generació a partir de restes agrícoles seria possible fins i tot amb un baix nivell de vendes de calor residual. La tercera configuració tracta el servei elèctric amb microxarxes basades en la gasificació de restes agrícoles de comunitats rurals. Els resultats de l’anàlisi en 5 comunitats mostren que el potencial de generació elèctrica a partir de la biomassa disponible supera la demanda elèctrica projectada. El finançament només a partir d’aportacions privades no seria viable amb les tarifes nacionals de consum elèctric actuals; en canvi, si s’aplica una tarifa de consum igual a la despesa actual en usos equivalents a l’electricitat (p.ex. llanternes i piles, bateries de cotxe), una subvenció del 35% sobre la inversió inicial permetria una taxa interna de retorn del 15% a inversors privats, mentre que un 60% la subvenció permetria una taxa interna de retorn del 25%.Els resultats d'aquesta investigació han estat considerats pels grups d'interès de Ghana dins de la formulació de polítiques i regulacions d'electrificació rural, i perspectives de trigeneració i els minigresos de biomassa també han desencadenat l'interès dels inversors privats internacionals i ghanesos
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Zanzi, Rolando. "Pyrolysis of biomass. Rapid pyrolysis at high temperature. Slow pyrolysis for active carbon preparation." Doctoral thesis, KTH, Chemical Engineering and Technology, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3180.
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<p>Pyrolysis of biomass consists of heating solid biomass inthe absence of air to produce solid, liquid and gaseous fuels.In the first part of this thesis rapid pyrolysis of wood(birch) and some agricultural residues (olive waste, sugarcanebagasse and wheat straw in untreated and in pelletized form) athigh temperature (800ºC1000ºC) is studied ina free fall reactor at pilot scale. These conditions are ofinterest for gasification in fluidized beds. Of main interestare the gas and char yields and compositions as well as thereactivity of the produced char in gasification.</p><p>A higher temperature and smaller particles increase theheating rate resulting in a decreased char yield. The crackingof the hydrocarbons with an increase of the hydrogen content inthe gaseous product is favoured by a higher temperature and byusing smaller particles. Wood gives more volatiles and lesschar than straw and olive waste. The higher ash content inagricultural residues favours the charring reactions. Charsfrom olive waste and straw are more reactive in gasificationthan chars from birch because of the higher ash content. Thecomposition of the biomass influences the product distribution.Birch and bagasse give more volatiles and less char thanquebracho, straw and olive waste. Longer residence time inrapid pyrolysis increase the time for contact between tar andchar which makes the char less reactive. The secondary charproduced from tar not only covers the primary char but alsoprobably encapsulates the ash and hinders the catalytic effectof the ash. High char reactivity is favoured by conditionswherethe volatiles are rapidly removed from the particle, i.e.high heating rate, high temperature and small particles.</p><p>The second part of this thesis deals with slow pyrolysis inpresence of steam for preparation of active carbon. Theinfluence of the type of biomass, the type of reactor and thetreatment conditions, mainly temperature and activation time,on the properties and the yield of active carbons are studied.The precursors used in the experiments are birch (wood) anddifferent types of agricultural residues such as sugarcanebagasse, olive waste, miscanthus pellets and straw in untreatedand pelletized form.</p><p>The results from the pyrolysis of biomass in presence ofsteam are compared with those obtained in inert atmosphere ofnitrogen. The steam contributes to the formation of solidresidues with high surface area and good adsorption capacity.The yield of liquid products increases significantly at theexpense of the gaseous and solid products. Large amount ofsteam result in liquid products consisting predominantly ofwater-soluble polar compounds.</p><p>In comparison to the stationary fixed bed reactor, therotary reactor increases the production of energy-rich gases atthe expense of liquid products.</p><p>The raw materials have strong effect on the yields and theproperties of the pyrolysis products. At equal time oftreatment an increase of the temperature results in a decreaseof the yield of solid residue and improvement of the adsorptioncapacity until the highest surface area is reached. Furtherincrease of the temperature decreases the yield of solidproduct without any improvement in the adsorption capacity. Therate of steam flow influences the product distribution. Theyield of liquid products increases while the gas yielddecreases when the steam flow is increased.</p><p><b>Keywords</b>: rapid pyrolysis, pyrolysis, wood, agriculturalresidues,biomass, char, tar, gas, char reactivity,gasification, steam, active carbon</p>
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Silva, Noely Bochi. "Avaliação química e ecotoxicológica de lodos e esgoto visando à utilização na agricultura." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257863.
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Orientador: Bruno Coraucci Filho<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo<br>Made available in DSpace on 2018-08-20T23:18:20Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012<br>Resumo: A destinação final de lodo de esgoto gerado nas estações de tratamento para a agricultura destaca-se por ser uma alternativa promissora e sustentável. Contudo, para se evitar efeitos adversos ao ecossistema e a saúde humana, este resíduo deve passar por uma rígida caracterização e monitoramento antes da sua aplicação. A Resolução CONAMA 375/2006 normatiza essa prática no Brasil, mas se restringe a alguns critérios químicos e biológicos que precisam ser monitorados. Recentemente, foi proposto um Índice de Perigo de Lodo de Esgoto (IPLE) baseado em ensaios ecotoxicológicos com organismos representativos, que expressa a periculosidade de lodos de esgoto quanto aos efeitos causados ao ecossistema. O objetivo deste trabalho foi realizar uma avaliação física, química, biológica e também ecotoxicológica em diferentes amostras de lodo de esgoto, para validar o IPLE e verificar a possibilidade do uso agrícola. De acordo com os resultados obtidos, as amostras de lodo de esgoto das ETEs dos municípios de Bernardino de Campos, Coronel Macedo, Fartura, Franca e Itaberá atendem aos limites preconizados por Brasil (2006) referentes aos metais potencialmente tóxicos e à concentração de patógenos, mas, segundo o IPLE, apenas as amostras de lodo de esgoto das estações de tratamento de esgoto dos munícipios de Franca, após 5 meses de acondicionamento em recipientes de polietileno, e de Sarutaiá estão aptas ao uso agrícola. Portanto, espera-se que a utilização do índice baseado em testes ecotoxicológicos se constitua em ferramenta auxiliar na caracterização inicial do lodo de esgoto para sua liberação e disposição na agricultura, na tentativa de proporcionar maior segurança aos integrantes da cadeia alimentar que deverão utilizar os recursos originados do ambiente agrícola onde foi utilizado o biossólido<br>Abstract: The disposal of sewage sludge generated at treatment plant for agriculture stands out as a promising and sustainable alternative. However, to avoid adverse effects to the ecosystem and human health, this residue must undergo into a strict characterization and monitoring prior to implementation the Resolution 375/2006, regulates the practice in Brazil, but it is restricted to some chemical and biological criteria that need to be monitored. Recently, it has been proposed a Hazard Index of Sewage Sludge (IPLE), based on ecotoxicological tests with representative organisms, which expresses the danger of sewage sludge on the effects caused to the ecosystem. The aim of this study was the physical, chemical, biological and ecotoxicological evaluation on different samples of sewage sludge, in order to validate the IPLE and verify the possibility of its agricultural use. According to the obtained results, the sewage sludge samples from treatment plant for municipal sewage of Bernardino de Campos, Coronel Macedo, Fartura, Franca and Itaberá comply with the limits recommended by Brazil (2006) concerning potentially toxic metals and pathogens concentration. Nevertheless, according to IPLE, only samples of sewage sludge from treatment plant for municipal sewage of Franca, after 5 months packaged in polyethylene containers, and Sarutaiá, are suitable for agricultural use. Therefore, it is expected that the use of the index based on ecotoxicological tests should constitute an auxiliary tool on initial sludge characterization for its agricultural release and arrangement in an attempt to provide improved safely to food chain members that should use resources from agricultural environment where sludges have been used<br>Mestrado<br>Saneamento e Ambiente<br>Mestra em Engenharia Civil
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Mello, Arthur Miola de. "Desempenho de uma enfardadora prismática no recolhimento de palhiço." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11148/tde-13102009-141028/.
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Um dos fatores que ainda retarda o uso do palhiço remanescente da colheita mecanizada para cogeração de energia é a falta de conhecimento de processos ou sistemas que viabilizem a retirada e transporte desse material até as unidades de cogeração. O objetivo desse trabalho foi estudar os desempenhos técnico, econômico e energético de uma enfardadora, em diferentes condições de distribuição de palhiço na superfície, buscando viabilizar o recolhimento do palhiço remanescente da colheita mecanizada. O ensaio foi realizado na Usina Iracema, município de Iracemápolis-SP, em área de cana-de-açúcar, colhida mecanicamente. A área foi dividida em três subáreas., com cinco repetições de 15 fardos cada. Os tratamentos utilizados foram: T1- palhiço in natura, sem enleiramento; T2- palhiço com enleiramento simples; T3- palhiço com enleiramento duplo. As principais avaliações foram: força na barra de tração, potência, velocidade efetiva, consumo de combustível, capacidades de produção e de campo efetivas, custos efetivos para o enfardamento, eficiência energética do enfardamento e potencial energético do palhiço recolhido. Os resultados mostraram que a demanda de força na barra para tracionar a enfardadora não mostrou diferenças entre os tratamentos e variou de 344,21 a 369,43 kgf, a demanda de potência exigida para o deslocamento do conjunto foi baixa podendo, dessa forma, reservar a maior parcela para o acionamento da TDP. Houve diferenças significativas nas velocidades operacionais, com valor de 4,9 km.h-1 no enfardamento sem enleiramento, 2,45 km.h-1 no enfardamento com leiras simples e 1,73 km.h-1 no enfardamento com enleiramento duplo. A capacidade de produção efetiva no tratamento T1 foi de 6,55 t.h-1, 8,1 t.h-1 no T2 e 5,81 t.h-1 no T3. A capacidade de campo efetiva foi de 7,75 t.ha-1 no T1; 9,2 t.ha-1 no T2 e 7,54 t.ha-1. O consumo horário de combustível no T1 foi de 7,86 l.h-1, no T2 foi de 7,48 l.h-1 e no T3 de 6,54 l.h-1. O consumo por tonelada de palhiço recolhido foi menor no tratamento T2 (0,92 l.t-1), seguido do T3 (1,13 l.t-1) e do T1 (1,20 l.t-1). O Tratamento T2 apresentou menor custo por tonelada de palhiço recolhido (7,45 R$.t-1), o custo no T1 foi de 9,33 R$.t-1 e no T3 foi de 10,49 R$.t-1. A eficiência energética da operação de enfardamento no T1 foi de 99,62%, no T2 foi de 99,71% e no T3 foi 99,64%. O potencial energético do palhiço recolhido no T1 foi 9,92 EBP.ha-1, no T2 foi 11,77 EBP.ha-1 e no T3 foi de 9,65 EBP.ha- 1. Diante dos resultados, pode concluir que: o enleiramento reduziu o teor de umidade do palhiço; a demanda de força de tração e de potência para tracionar a enfardadora foram pequenas; o sistema de recolhimento de palhiço em leiras simples apresentou melhor desempenho econômico e energético; por se tratar de uma enfardadora de baixa capacidade efetiva é inapropriada para operação em grandes áreas; considerando-se as inúmeras variáveis, intervenientes nos 3 tratamentos, entende-se que a melhor opção para o uso desta enfardadora é operação em área com enleiramento simples do palhiço.<br>One of the factors that still delay the use of the residue of sugar cane mechanical harvest for energy cogeneration is the lack of knowledge of processes or systems that allow the materials removal and transportation to the cogenerations place. The objective of this research was study the performances technical, economic and energetic of a bailing, in different conditions of distribution of sugar cane residue on the surface, trying to make viable the collection of the remaining mechanized harvest. The test was realized at sugar cane mill Iracema, located in Iracemápolis-SP, in an area of sugar cane, mechanically harvested. The area was divided into three sub-areas, with five replicates of 15 bales each. The treatments were: T1-sugar cane residue \"in natura\", without row; T2-sugar cane residue with simple row; T3-sugar cane residue with double row. The main evaluations were: force on traction bar, power, effective speed, fuel consumption, capacitys production and effectives field, bailings effectives costs, bailings energetic efficiency and energetic potential of the sugar cane residue bailed. The results showed that the force demand on traction bar to pull the baler showed no differences between the treatments and ranged from 344.21 to 369.43 kgf, the power demand required for the displacement the tractor and the baler was low and, thus, reserve the largest portion to operate the PTO. There were significant differences in operating speeds, with a value of 4.9 km.h-1 on baling without row, 2.45 km.h-1 on baling with simple row and 1.73 km.h-1 on baling with double row. The effective production capacity in the T1 was 6.55 t.h-1, 8.1 t.h-1 in T2 and 5.81 t.h-1 in T3. The effective field capacity was 7.75 t.ha-1 in T1, 9.2 t.ha-1 in T2 and 7.54 t.ha-1. The hourly consumption of fuel at T1 was 7.86 l.h-1 in T2 was 7.48 l.h-1 and T3 of 6.54 l.h-1. The consumption per ton of sugar cane residue collected was lower in treatment T2 (0.92 l.t-1), followed by T3 (1.13 l.t-1) and T1 (1.20 l.t-1). The treatment T2 had lower cost per ton of sugar cane residue baled (7.45.R$.t-1), the cost in T1 was 9.33 R$.t-1 and T3 was 10.49 R$.t-1. The energetic efficiency of the baling operation in T1 was 99.62% at T2 was 99.71% and 99.64% in T3. The energetic potential of the sugar cane residue baled at T1 was 9.92 EBP.ha-1 in T2 was 11.77 EBP.ha-1 and T3 was 9.65 EBP.ha-1. The results may conclude that: the rows operation reduced the sugar cane residue humidity, the demand of the traction force and power to pull the baler were small, the simple rows was the system that showed better performance and energy economic; the baler had a small effective capacity for this is inappropriate for large areas; considering the many variables that affects the treatments, understood that the best option for the use of this baler is operating in sugar cane residues areas with simple rows.
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Achale, Travolta Achalle [Verfasser], Markus [Akademischer Betreuer] Euring, Markus [Gutachter] Euring, and Ralph [Gutachter] Mitlöhner. "Agricultural residues and the wood of umbrella tree (Musanga cecropioides) as raw materials for the development of reduced emission particleboards / Travolta Achalle Achale ; Gutachter: Markus Euring, Ralph Mitlöhner ; Betreuer: Markus Euring." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1210264730/34.
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Melo, Priscilla Siqueira. "Composição química e atividade biológica de resíduos agroindustriais." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-21102010-161908/.
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A agroindústria tem se expandido para atender a crescente demanda populacional por alimentos. Dentro deste contexto, o Brasil com sua economia fortemente baseada no agronegócio contribui para a geração de grande quantidade de resíduos agroindustriais resultantes das atividades de processamento. Estes resíduos, por sua vez, representam um grave problema, pois aparentemente sem aplicação viável, são descartados diretamente ao meio ambiente. Muitos deles são ricos em compostos bioativos, amplamente reconhecidos pelas suas propriedades promotoras de saúde e aplicações tecnológicas, tais como antioxidantes e antimicrobianos, representando, portanto, potenciais fontes naturais destas substâncias. Neste trabalho, foram analisados 15 resíduos agroindustriais coletados em Bento Gonçalves, RS, Petrolina, PE, Monte Alto e Jacareí, SP. São eles: bagaços de uva Pinot Noir, Petit Verdot, Cabernet Sauvignon, Isabel (tintas), Moscato, Verdejo (brancas); engaços de uva Cabernet Sauvignon; Syrah (tintas), Moscato, Verdejo (brancas); borras de vinho tinto e branco; bagaço de tomate; bagaço de goiaba e bagaço de malte. As amostras foram extraídas com solventes de diferentes polaridades (hexano, clorofórmio, acetato de etila, etanol:água (80:20, v/v) e água) e os extratos analisados quanto o teor de compostos fenólicos totais e atividade antioxidante (DPPH). As amostras e solventes que apresentaram os maiores teores de compostos fenólicos e atividade antioxidante pelo método DPPH no screening inicial seguiram para as outras análises de atividade antioxidante (EC50, ABTS, auto-oxidação do beta-caroteno/ácido linoléico e Rancimat), atividade antimicrobiana e composição química por CG-EM. Engaço branco Moscato e bagaço Pinot Noir apresentaram os maiores teores de compostos fenólicos totais, 48,61 e 40,79 mg GAE/g nos extratos etanólicos, respectivamente. O extrato etanólico do bagaço Pinot Noir apresentou elevada atividade antioxidante em todos os ensaios. Além dele, extratos de engaço branco (EC50, ABTS), bagaço Petit Verdot (ABTS, auto-oxidação do beta-caroteno), engaço tinto (EC50, auto-oxidação do betacaroteno) e bagaço Cabernet Sauvignon (Rancimat) apresentaram os melhores resultados nesses ensaios, e em muitos deles, comparáveis a do antioxidante sintético BHT. Nenhuma das amostras apresentou atividade antimicrobiana na concentração de 32 mg/mL contra S. aureus, S. mutans e A. naeslundii pelo método da difusão em ágar. O perfil químico das amostras revelou que a epicatequina foi o composto majoritário presente tanto nos extratos etanólicos quanto aquosos de todos os resíduos vinícolas analisados. Já para os bagaços de goiaba e tomate, a quercetina foi o fenólico predomimante. Outros compostos tais como ácido gálico, ferúlico, caféico, vanílico, sinápico, resveratrol, siríngico também foram identificados. Com base nos resultados é possível concluir que as amostras analisadas, particularmente os resíduos vinícolas, são ricas em compostos bioativos de elevado poder antioxidante, representando, portanto, uma potencial fonte destes compostos para aplicação na indústria de alimentos.<br>The agricultural industry has expanded to meet the growing population demand for food. Within this context, Brazil with its economy heavily based on agribusiness contributes to the generation of large amounts of industrial residues resulting from processing activities. These residues represent a serious problem because are discarded directly into the environment. Many of them are rich in bioactive compounds, widely recognized for its health-promoting properties and technological applications, such as antioxidants and antimicrobials, thus representing potential sources of these natural substances. In this study, we analyzed 15 residues collected in Bento Gonçalves, RS, Petrolina, PE, Jacareí and Monte Alto, SP. They are: grape pomace - Pinot Noir, Petit Verdot, Cabernet Sauvignon, Isabel (red), Moscato, Verdejo (white), stems of grape - Cabernet Sauvignon, Syrah (red), Moscato, Verdejo (white), wine lees red and white, tomato pomace, guava pomace and malt pomace. The samples were extracted with solvents of different polarities (hexane, chloroform, ethyl acetate, ethanol:water (80:20, v/v) and water) and the extracts analyzed for the content of total phenolics and antioxidant activity (DPPH) . The best solvents and samples selected on the basis of these two parameters followed for the other tests of antioxidant activity (EC50, ABTS, auto-oxidation of beta-carotene/linoleic acid and Rancimat), antimicrobial activity and chemical composition by GC-MS. Stems white Moscato and Pinot Noir pomace showed the highest levels of total phenolics, 48.61 and 40.79 mg GAE/g in the ethanol extracts, respectively. The ethanol extract of Pinot Noir pomace showed high antioxidant activity in all tests. Besides him, extracts of white stem (EC50, ABTS), Petit Verdot pomace (ABTS, auto-oxidation of beta-carotene), red stems (EC50, auto-oxidation of beta-carotene) and bagasse Cabernet Sauvignon (Rancimat) presented the best results of these tests, and many of them comparable to the synthetic antioxidant BHT. None of the samples showed antimicrobial activity to the concentration of 32 mg/mL against S. aureus, S. mutans and A. naeslundii by agar diffusion method. The chemical profile of the samples revealed that epicatechin is the major compound both in aqueous and ethanol extracts in all waste wine analyzed. In tomato and guava pomaces, quercetin is the predominant phenolic. Other compounds such as gallic acid, ferulic, caffeic, vanillic, sinapic, resveratrol, syringic were also identified. Based on these results we conclude that the samples analyzed, particularly the waste wine, are rich in bioactive compounds with high antioxidant power and have great potential application in the food industry.
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Coluna, Naraisa Moura Esteves. "Análise do potencial energético dos resíduos provenientes da cadeia agroindustrial da proteína animal no Estado de São Paulo." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/106/106131/tde-07062016-084519/.
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A cadeia agroindustrial de proteína animal é importante setor para a economia brasileira. A pecuária é considerada um dos principais causadores de danos ambientais, como contaminação das fontes dágua e assoreamento dos recursos hídricos; produção e emissão de gases do efeito estufa (GEE). As criações animais e os abatedouros geram elevadas quantidades de resíduos e efluentes, que possuem grande carga orgânica, podendo ser tratados por sistema anaeróbio, tendo como resultado a geração de biogás. Dentre as vantagens dessa aplicação, tem-se: o uso do biogás como fonte de energia elétrica e térmica, além da utilização do biometano, diversificação da matriz energética, com diminuição da dependência do sistema hidrológico, bem como do uso de térmicas a combustíveis fósseis. Também, registra-se o fortalecimento da geração distribuída e uma matriz mais limpa, melhorando as emissões de GEE do setor e contribuindo para a sustentabilidade direta da atividade. Apesar das vantagens amplamente conhecidas do biogás, ainda no Brasil essa fonte de energia ainda é pouco utilizada, significando cerca de 1% da matriz brasileira. O objetivo geral deste estudo é identificar regiões no Estado de São Paulo que possuam potencial de produção de biogás e biometano a partir dos resíduos agropecuários e agroindústrias do setor de proteína animal a partir de duas metodologias distintas, do IPCC e da CETESB, bem como o seu potencial energético para a geração de energia elétrica, analisando as politicas e barreiras existentes. Os resultados encontrados demonstraram grandes inconsistências entre elas e a necessidade de validarmos uma metodologia que realmente considere as diferenças de sistema de produção, climáticas, tecnologias existentes. O levantamento do potencial almeja subsidiar o desenvolvimento de políticas públicas adequadas de incentivo à sua realização, reduzindo as emissões de GEE do setor e, o mais importante, contribuir para a sustentabilidade direta da atividade atingindo a base da cadeia produtiva da agropecuária, que são os criadores e produtores familiares.<br>The agro-industrial chain of animal protein is important sector for the Brazilian economy. Livestock is considered a major cause of environmental damage, such as pollution of water sources and silting of water resources; production and emission of greenhouse gases (GHGs). Animal creations and slaughterhouses generate large amounts of waste and wastewater, which have high organic load, can be treated by anaerobic system, resulting in the generation of biogas. Among the advantages of this application, it has: the use of biogas as a source of electric and thermal energy, as well as use of biomethane, diversification of energy sources, with reduced dependence on the hydrological system and the use of thermal fossil fuels. Also, register the strengthening of distributed generation and a cleaner matrix, improving the GHG emissions from the sector and contributing to the sustainability of direct activity. Despite the widely known advantages of biogas, even in Brazil this source of energy it is still little used, meaning about 1% of the Brazilian matrix. The aim of this study is to identify regions in the State of São Paulo that have biogas production potential and biomethane from agricultural residues and agro-industries of the animal protein sector from two different methodologies, the IPCC and CETESB, as well its energy potential for the generation of electricity, analyzing existing policies and barriers. The results showed major inconsistencies between them and the need to validate a methodology that actually consider the production system differences, climate, existing technologies. The survey of the potential aims to support the development of appropriate public incentive for achieving policies, reducing GHG emissions in the industry and, most importantly, contribute to direct sustainability of the activity reaching the base of the production chain of agricultural, which are the creators and family farmers.
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Falcão, Audrey de Arruda. "Analise quimica de residuos solidos para estudos agroambientais." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250585.
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Fisher, P. M. "Residual concentrations and persistence of the anticoagulant rodenticides brodifacoum and diphacinone in fauna." Lincoln University, 2009. http://hdl.handle.net/10182/930.
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Brodifacoum is a highly effective anticoagulant rodenticide that presents a secondary hazard to some non-target wildlife. The high acute toxicity of brodifacoum to mammals and birds, and its prolonged persistence in liver predicates secondary risk to predators and scavengers of poisoned rodents. Hence there is a need to improve ability to monitor and predict hazards of brodifacoum to non-targets, and optimise use patterns accordingly. Use of a less persistent anticoagulant rodenticide, diphacinone, is an alternative approach currently under investigation in New Zealand. This thesis describes a series of laboratory and pen studies that address information gaps relevant to the assessment of non-target hazards in continued use of brodifacoum, and of using diphacinone as an alternative. Non-lethal techniques for determining sublethal brodifacoum exposure in birds was investigated in chickens. Elevation of prothrombin time was a less reliable index than residual concentrations in tissues. Samples requiring less invasive procedures, such as dried blood spots or faeces, have potential to detect recent sublethal brodifacoum exposure and refinement of these indices could be useful in proactive monitoring of avian wildlife. Residual brodifacoum in eggs of sublethally-exposed hens raised further questions regarding wider non-target hazard and adverse effects on development of fertile eggs or chicks. A laboratory trial with rats found a positive correlation between residual brodifacoum concentrations in liver and the amount of brodifacoum ingested as bait. An estimated 14-22% of ingested brodifacoum was excreted in rat faeces in the period between ingestion of a lethal dose and death, indicating another potentially significant environmental pathway for brodifacoum transfer. In considering diphacinone as a less persistent alternative rodenticide to brodifacoum, evaluation of residual concentrations and persistence in pig tissues was required to estimate secondary hazard to human consumers and adequate with-holding periods for hunting feral pigs in areas where diphacinone was applied. A pen trial showed that domestic pigs were more susceptible to diphacinone toxicity, and thus primary poisoning risk, than previously estimated. Hepatic half-life of diphacinone in pigs was approximately 14 days, indicating reduced persistence in comparison to brodifacoum and enabling estimates of with-holding periods for hunting feral pigs from areas where diphacinone baits were applied. To investigate potential hazards of diphacinone use to invertebrates a trial using tree weta, a native New Zealand invertebrate, was undertaken. Weta readily ate diphacinone wax block baits with no mortality or weight loss evident, indicating low susceptibility. Residual whole-body diphacinone concentrations did not increase with the amount of diphacinone bait eaten. A simple, deterministic risk assessment suggested that, as a single secondary exposure, the maximum diphacinone concentration measured in weta would present a low risk to non-target birds. Given international recognition of the high secondary hazard and corresponding restrictions on use of brodifacoum, continued availability of brodifacoum to non-licensed users and sustained field applications for possum and rodent control in New Zealand is an exceptional use pattern. New data in this thesis suggest that baiting strategies that minimise the amount of brodifacoum available in the environment are important and regulatory review of some New Zealand brodifacoum applications should address this. In parallel, development of diphacinone as an alternative to brodifacoum should continue, as new data here confirms lower persistence in mammalian liver than brodifacoum, and also indicates low toxicity to invertebrates. However further investigation of multiple-exposure hazard and potential sublethal effects of diphacinone on non-target mammals and birds is warranted before extensive and sustained field applications of diphacinone are undertaken.