Dissertations / Theses: 'Biogas production potential'

1

Shi, Chen. "Potential Biogas Production from Fish Waste and Sludge." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171807.

Full text

Abstract:

In order to decrease the pollution of the marine environment from dumping fish waste and by-catch, alternative use for co-digestion with sludge in anaerobic condition was studied. The purpose of this project is to optimize the methane potential from adjustment of the proportion among mixed substrates. Ten groups of different proportions among fish waste, by-catch and sludge were conducted with AMPTS II instrument under mesophilic condition (37 ± 0.5 ºC), by means of the principle of BMP test. The ratio of inoculums and mixed substrate was set as 3:2. The optimal MP obtained after an experiment with 13 days digestion was 0.533 Nm3 CH4/kg VS from the composition of sludge, by-catch and fish waste as 33 %, 45 % and 22 %. It was improved by 6 % and 25.6 %, to compare with the previous studies by Almkvist (2012) and Tomczak-Wandzel (personal communication, February 2012) respectively.

APA, Harvard, Vancouver, ISO, and other styles

2

Lopes, Alice do Carmo Precci. "Biogas production potential from kraft pulp mill sludge." Universidade Federal de Viçosa, 2017. http://www.locus.ufv.br/handle/123456789/10437.

Full text

Abstract:

Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2017-05-30T13:10:23Z No. of bitstreams: 1 texto completo.pdf: 2018178 bytes, checksum: f542263170df07213000e3e4bebf72ed (MD5)
Made available in DSpace on 2017-05-30T13:10:23Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2018178 bytes, checksum: f542263170df07213000e3e4bebf72ed (MD5) Previous issue date: 2017-03-28
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O processo de fabricação da polpa celulósica kraft demanda elevada quantidade de água e energia. Embora a indústria gere parte de sua própria energia pela queima do licor negro na caldeira de recuperação e biomassa residual na caldeira de biomassa, a indústria ainda é dependente de energia elétrica e combustíveis fósseis adicionais. Devido ao aumento da tarifa de energia, a indústria de celulose tem sido motivada a aumentar sua eficiência energética, tornando-se autossuficiente. A produção de biogás a partir do lodo gerado na estação de tratamento de efluentes da indústria constitui uma potencial alternativa de gerenciamento dos resíduos e produção de energia. O objetivo principal desta dissertação foi avaliar o potencial da produção de biogás a partir dos lodos primário e secundário provenientes da indústria de celulose kraft branqueada. A dissertação foi estruturada em 5 Capítulos desenvolvidos em forma de artigos científicos. O Capítulo 1 apresentou uma revisão de literatura sobre os processos de produção de celulose kraft e de biogás, bem como um panorama sobre legislações brasileiras relacionadas à implantação de biodigestores. Foi concluído que há pouco estudo relativo à digestão anaeróbia de lodo de celulose kraft. Adicionalmente, apesar de o Brasil apresentar um grande potencial de produção de biogás, o país ainda carece de incentivos governamentais no setor. O Capítulo 2 objetivou (i) identificar a melhor relação substrato/inóculo (2/1, 1/1 e 0.4 g VS substrato /g VS inóculo ); (ii) identificar o melhor tipo de inóculo (lodo de UASB ou lodo de UASB + estrume); e (iii) estimar o potencial de substituição da energia elétrica demandada pelo sistema de aeração da estação de tratamento de efluentes da indústria de celulose kraft branqueada a partir do biogás produzido. Para tanto, foram utilizados como substratos o lodo primário (PS), lodo secundário (SS) e a mistura de ambos (MIX). Os resultados mostraram que o lodo secundário possuiu maior potencial de produção de biogás para uma relação 1/1 g VS substrato /g VS inóculo , utilizando lodo de UASB como inóculo. O estrume aumentou a produção de metano do lodo primário para relação S/I 1/1, porém pré-tratamentos devem ser testados de modo a aumentar a biodegradabilidade do substrato. Por fim, o biogás produzido apresentou potencial de substituir 23% daxi demanda de energia elétrica da estação de tratamento de efluentes. O Capítulo 3 objetivou (i) estimar o potencial de produção de biogás em condições termofílicas a partir do PS, SS e MIX; (ii) calibrar o modelo de digestão anaeróbia desenvolvido por Rajendran et al. (2014); e (iii) determinar a melhor composição do lodo e a influência de adição de nitrogênio no sistema de digestão anaeróbia a partir de simulações numéricas. Foi identificado que (i) a máxima produção de metano foi atingida pelo lodo secundário em 30 dias (46.9 NmL CH4/g VS); (ii) o modelo de digestão anaeróbia foi aplicável para lodo de celulose kraft após ajustes; (iii) a melhor composição de lodo foi de 21.62% de carboidratos, 61,67% de lipídeos e 16.72% de proteínas. A adição de nitrogênio aumentou a produção de metano para o PS e o MIX, mas reduziu para o SS. Os Capítulos 4 e 5 foram desenvolvidos por estudantes intercambistas como parte do programa Living Lab Biobased Brazil. Os objetivos do Capítulo 4 foram ajustar o modelo de Rajendran et al. (2014) para a condição mesofílica e simular o uso do biogás em forma de eletricidade e calor. A partir da simulação foi possível produzir 88 GJ/d de calor e 148 kW de potência elétrica. Além disso, a partir do ajuste do modelo de Rajendran et al. (2014) para a condição mesofílica, foram propostas melhorias para o modelo. Por fim, o Capítulo 5 objetivou apresentar potenciais alternativas para o gerenciamento do lodo de celulose kraft pós-digestão anaeróbia, utilizando a ferramenta de Análise de Multi-Critério simplificada. A partir das alternativas avaliadas (aterro sanitário, aplicação no solo, compostagem, incineração, pirólise/gaseificação e produção de algas), a compostagem se apresentou como a melhor opção.
The kraft pulping process is energy intensive. Although the mill generates part of its own energy by burning the black liquor in the recovery boiler and wooden biomass in the biomass boiler, it still relies on additional electricity and fossil fuel sources. Due to an energy price increase, the pulp industry has been driven to optimize its energy efficiency and self-sufficiency. One attractive industrial opportunity is to produce biogas from sludge using the anaerobic digestion technology. Thus, the main objective of this dissertation was to evaluate the potential of biogas production from bleached kraft pulp mill primary and secondary sludges. The dissertation was structured in 5 Chapters written as scientific papers. Chapter 1 presented a literature review about kraft pulp mills, biogas production, and legislations related to the implantation of biodigesters. It was concluded that there are still very few studies related to the anaerobic digestion of kraft pulp mill sludges. Additionally, although Brazil has great potential for biogas production, the country still faces barriers related to political incentives. Chapter 2 aimed at (i) identifying the best substrate to inoculum ratio (2/1, 1/1, and 0.4 g VS substrate /g VS inoculum ); (ii) identifying the best inoculum type (UASB sludge and UASB sludge + cow dung); and (iii) estimating the potential of substituting the electricity demand of the mill’s effluent treatment plant (ETP) aeration system. The substrates used consisted of primary (PS) and secondary (SS) sludges, and the mixture (MIX) between PS and SS. The results showed that the SS presented the highest methane production, with an optimal ratio of 1 g VS substrate /g VS inoculum using UASB sludge as inoculum. Cow dung increased the methane production of the PS for S/I = 1/1, but pre-treatment of PS should be tested to increase the substrate biodegradability. Finally, the methane yield led to a potential substitution of 23% of the ETP electricity demand. Chapter 3 aimed to (i) estimate potential biogas production under thermophilic conditions for the same substrates; (ii) calibrate the anaerobic digestion model developed by Rajendran et al. (2014); and (iii) simulate the best sludge composition and the influence of nitrogen addition on anaerobic digestion system. It was found that the (i) the maximum methane yield was achieved with theix secondary sludge at 30 days (46.9 NmL CH4/g VS); (ii) the applied anaerobic digestion model was applicable for the kraft pulp mill sludge after minor adjustments; (iii) optimal sludge composition was found to be 21.62% carbohydrates, 61.67% lipids and 16.72% proteins. The addition of nitrogen increased the methane yield for PS and MIX, but decreased it for SS. Chapters 4 and 5 were the result of work developed by bachelor exchange students as part of the Living Lab Biobased Brazil Program. Chapter 4 aimed to adjust the Rajendran et al. (2014) model for mesophilic conditions and simulate biogas use in the form of electricity and heat. From the simulation, a potential heat production of 88 GJ/d and electric power of 148 kW was found. From Chapter 4, possibilities for improving the Rajendran et al. (2014) model were proposed. Finally, Chapter 5 aimed at giving an insight into the possible alternatives for managing the anaerobically digested kraft pulp mill sludge using a simplified Multi- Criteria Decision Analysis tool. From the analyzed alternatives (landfill, land application, composting, incineration, pyrolysis/gasification and algae production), composting appeared to be the most suitable alternative.

APA, Harvard, Vancouver, ISO, and other styles

3

Rodriguez, Chiang Lourdes Maria. "Methane potential of sewage sludge to increase biogas production." Thesis, KTH, VA-teknik, Vatten, Avlopp och Avfall, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-96294.

Full text

Abstract:

Sewage sludge is treated with the biological process of anaerobic digestion in which organic material of a substrate is degraded by microorganisms in the absence of oxygen. The result of this degradation is biogas, a mixture mainly of methane and carbon dioxide. Biochemical Methane Potential tests are used to provide a measure of the anaerobic degradability of a given substrate. This study aims to determine the methane potential in Sjöstadsverket’s sludge this will moreover determine the viability of recycling the digested sludge back into the anaerobic system for further digestion. Batch digestion tests were performed in both Sjöstadsverket’s (S1) and Henriksdal’s (H2) sludge, for a reliable comparison. An inoculum to substrate ratio of 2:1 based on VS content was used and BMP tests presented results that S1 and H2 in the 20 days of incubation produced 0.29 NLCH4/gVS and 0.33 NLCH4/gVS respectively. A second experiment considering the same amount of substrate (200ml) and inoculum (200ml) for each sample, showed that Control S1 had a higher methane potential than Control H2, 0.31 NL/gVS and 0.29 NL/gVS respectively. All the samples containing Sjöstadsverket’s inoculum presented a higher volume of total accumulated gas (measured in Normal Liters), however methane potentials are low. Results demonstrated that methane production in samples S1 and Control S1 was originating from the grams of VS in the inoculum itself after depletion of all the soluble organic material in the substrate. This suggested that Sjöstadsverket’s sludge can endure a higher organic load rate and that the digested sludge still has potential to produce biogas, hence the recycling of this can enhance the biogas production in the digestion system.

APA, Harvard, Vancouver, ISO, and other styles

4

Björklund, Simon, and Niklas Öhman. "Biogas opportunities in Curitiba : Analysis of business potential for biogas production from municipal solid waste." Thesis, KTH, Energiteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211698.

Full text

Abstract:

The Brazilian city ofCuritiba produces 2 500 tons of MSW (municipal solid waste) per day that is landfilled.In an effort to find a more sustainable solution for waste management, the objective of this study was to investigate the potential for producing biogas from anaerobic digestion by analyzing the feasibility of small-scale decentralized biogas production as well as centralized production at commercialscale. A field study was carried out to map specific local circumstances and togather data by interviews and literature. Different methods of attaining the organic waste were reviewed and the options for biogas production were evaluated by comparing the highest investment cost admissible for a positive netpresent value of a prospective investment with estimations of investment costs from literature sources. Small-scale decentralized biogas production was found to be the most economically and socially viable option. For centralized production, the results were inconclusive but indicated the potential of profitable business cases. It is estimated that wet digestion in a floating-drum ortubular digester is most suitable for small scale applications while acontinuously dry digestion system is best suited for large scale biogasproduction in Curitiba. The sensitivity analysis showed that the amount oforganic waste available as well as the price of sold products had the biggest economic impact in the scenarios. It was found that any implementation of controlled anaerobic digestion would decrease the total global warming potential of the waste management system. It is recommended that the municipality proceed with and expand a pilot project at Mercado Regional, as well as exploring possibilities for more efficient waste collection, along with gathering more specific data on compositions and quantities for different waste flows. The study was carried out in the scope of a cooperation between KTH, the Swedish EnvironmentalProtection Agency, Municipality of Curitiba and local universities in Paraná,Brazil.
Den brasilianska staden Curitiba producerardagligen 2 500 ton MSW (municipal solid waste) som i dagsläget deponeras. Isyfte att hitta en mer hållbar lösning för avfallshantering ämnade denna studieundersöka potentialen för biogasproduktion via rötning genom att analyseragenomförbarheten av småskalig decentraliserad biogasproduktion samtcentraliserad produktion i kommersiell skala. En fältstudie genomfördes för attkartlägga specifika lokala omständigheter och samla in data genom intervjueroch litteratur. Olika metoder för insamling av organiskt avfall granskades ochalternativen för biogasproduktion utvärderades genom att jämföra de högstatillåtna investeringskostnaderna för ett positivt nettonuvärde av en framtidainvestering med uppskattade investeringskostnader från litteraturkällor.Småskalig decentraliserad biogasproduktion visade sig vara det bästaalternativet från ett ekonomiskt och socialt perspektiv. För centraliseradproduktion var resultaten tvetydiga men indikerade att en lönsam affärsmodellpotentiellt kunde utarbetas. Rötning av substrat med hög fuktighetshalt i en“floating-drum” reaktor eller en tub-formad reaktor bedöms vara bäst lämpat förbiogasproduktion i liten skala emedan ett kontinuerligt system för rötning avtorra substrat bedöms som det bästa alternativet för storskaligbiogasproduktion. Känslighetsanalysen visade att mängden insamlat organisktavfall samt priset på slutprodukterna hade störst påverkan på det ekonomiskautfallet. Studien påvisade även att en implementering av en rötningsanläggningskulle minska växthuspotentialen i avfallshanteringssystemet oavsett skala. Detrekommenderas att kommunen fortsätter med och utvecklar ett pilotprojekt iMercado Regional, samt undersöker möjligheterna för effektivare sophämtning ochsamlar mer specifika data om sammansättning och kvantitet för olika sopflöden. Arbetetutfördes som ett led i samarbetet mellan KTH, svenska Naturvårdsverket,Curitiba kommun och lokala universitet i Paraná, Brasilien.

APA, Harvard, Vancouver, ISO, and other styles

5

Olsson, Alexander. "A Comparative Study of Swedish and Chinese Biogas Production with a Brief Economical Feasibility Analysis." Thesis, KTH, Skolan för kemivetenskap (CHE), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-150785.

Full text

Abstract:

This Master of Science and Engineering thesis in Chemical Engineering treats biogas production in China. The thesis is divided into two parts. The first part contains an energy potential and situation analysis of biogas in China and a comparison with the situation in Sweden. The biogas potential in China is 950-2180 TWh depending on source. Specially, the potential from fish waste is 11 TWh. Part 1 also includes batch experiments where co-digestion of corn straw and swine manure is performed using substrate from Dajugezhuang in Tianjin. The experiments were executed at Tianjin Academy of Environmental Science. The experiments do not show a significant reduction in COD when co-digesting manure with straw and are connected with uncertainty. The experiments should be executed again with the recommendations given in this report. It is discovered that the inoculum affects the C:Nratio a lot. When co-digesting experiments are being performed, an inoculum that have a C:N-ratio close to the desired must be used. This is due to that the organic loading rate must be kept low. Part 2 of this thesis is an economical feasibility analysis and market investigation of biogas in China. A model is created using excel, where economic data from biogas plants in China are used to estimate the profit of producing biogas in China. The model indicates that the most feasible choice is to upgrade the biogas and inject it to the gas grid. This is due to the lower investment cost for an upgrading unit compared to an electricity-generating unit. The model uses electricity and gas prices from different provinces in China. Guangdong is the province with the highest electricity price and Ningxia the province with the lowest electricity price. The gas price in Guangdong is also high, but highest in Guangxi and Yunnan. The lowest gas price is found in Ningxia. Part 2 also discuss problems with the current situation for biogas producers in China. Investment subsidies from the government instead of product subsidies has led to a situation where China has over 30 million biogas reactors, but very low yield. The current situation means low incentives for selling the products from anaerobic digestion, biofertilizers, bio-methane, electricity and heat. The grid connection limit on electricity generators of >500 kW limits the number of grid-connected plants to less than 10. vi
Detta examensarbete i kemiteknik behandlar biogasproduktion i Kina. Examensarbetet är uppdelat i två delar. Den första delen innehåller en energipotential och nulägesanalys av biogas i Kina och en jämförelse med situationen i Sverige (kapitel 1). Biogas potentialen i Kina är 950-2180 TWh beroende på olika källor. Speciellt är potentialen från fiskarens 11 TWh. Del 1 omfattar även satsvisa utrötningsförsök där samrötning av majshalm och svingödsel sker med hjälp av substrat från Dajugezhuang i Tianjin. Experimenten utfördes vid Tianjin Academy of Environmental Science. Experimenten visar inte en signifikant minskning av COD vid samrötning av grisgödsel med halm och försöken är behäftade med osäkerhet. De bör därför genomföras igen efter de rekommendationer som ges i denna rapport. Det upptäcks att den ymp som används påverkar C:N-kvoten mycket. När samrötningsexperiment genomförs, ska en ymp som har en C:N-kvot nära den önskade för försöket användas. Detta beror på att den organiska belastningen måste hållas låg. Del 2 i detta examensarbete är en feasibility-analys och marknadsundersökning av biogas i Kina. En modell skapades i Excel, där ekonomiska data från biogasanläggningar i Kina används för att uppskatta resultatet att producera biogas i Kina. Modellen visar att det mest ekonomiska sättet att använda biogasen är att uppgradera den och injicera det till gasnätet. Detta beror på den lägre investeringskostnaden för en uppgraderingsanläggning jämfört med ett elkraftverk. Modellen använder el- och gaspriser från olika provinser i Kina. Guangdong är provinsen med det högsta elpriset och Ningxia provinsen med det lägsta elpriset. Gaspriset i Guangdong är också hög, men högst i Guangxi och Yunnan. Det lägsta priset på gas finns i Ningxia. Del 2 diskuterar också problem med den nuvarande situationen för biogasproducenter i Kina. Investeringsstöd från staten i stället för subventioner av produkterna har lett till en situation där Kina har över 30 miljoner biogasreaktorer, men mycket lågt utbyte i reaktorerna. Den nuvarande situationen innebär få incitament för försäljning av produkterna från rötningsprocessen, bio-gödsel, bio-metan, el och värme. Den nätanslutningsgräns som finns för elproducenterna på >500 kW, begränsar antalet nätanslutna anläggningar i Kina till mindre än 10 stycken. vii

APA, Harvard, Vancouver, ISO, and other styles

6

Norr, Patrik. "Analysis and assessment of biogas production potential in Sweden for 2050." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-393916.

Full text

Abstract:

The world is about to shift from fossil fuel dependency to independency. The national agenda of Sweden has put forth future goals of becoming a zero net greenhouse gas emitter by the year 2045 and before that, having an 80 % fossil fuel independent transportation fleet by 2030. In order to achieve these goals, the form of energy used in the transport sector needs to be changed into a more renewable solution. Biogas could be part of the solution. The aim of this report has been to review earlier research regarding the future biogas potential in Sweden and to examine how realistic and practically feasible these are. Three of the substrates that has shown the highest future potential according to earlier research; energy crops, manure and black liquor has been chosen for investigating their future potential. Interviews was made with biogas researcher in Sweden as well as government employees working with biogas and other biofuels. Scenario building was another method used were the report have created four future scenarios with varying optimistically future economic and technical outcomes using more practical limitations and restrictions. The result was a combined future potential of between 0,42 – 77,54 TWh/annually from all three substrates using the values and information gathered from the interviewers regarding how to calculate the potential. The result shows that depending on how lucrative the future financial support systems and subsidies as well as how efficient the technical breakthroughs will be, biogas can become a large contributor to the transport sectors transition in becoming less fossil fuel dependent.

APA, Harvard, Vancouver, ISO, and other styles

7

Tesfaye, Tefera Tadious. "Potential for biogas production fromslaughter houses residues in Bolivia : Systematic approach and solutions to problems related to biogas production at psychrophilic temperature." Thesis, KTH, Energi och klimatstudier, ECS, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48101.

Full text

Abstract:

Residues from slaughter houses offer an abundant resource in Bolivia. The residues can beused for biogas production with biofertilizer as a bi-product. These resources are, however,currently not being used. Instead, they are released in water systems, implying heavycontamination, e.g., on the Lake Titicaca in western Bolivia. Severe environmental effects areobserved in the lake and connected water systems. The residues from slaughter houses are animportant part of the problem. If the contamination continues, important environmental values willbe lost. Information around the resource is scarce, since no extensive inventory has been carried out. It isestimated that officially registered slaughter houses in the four major cities of Bolivia aloneproduce over 75 tons of organic residues per day. This flow of residues has increased since theworld market for animal fodder based on blood dropped significantly. In addition, there is littleexperience of biogas production in cold environments at that altitude, almost4000 meters over sea level. Production of biogas from waste is one of the most common methods to generate energy and at thesame time best waste reduction methods. Biogas production can be practiced favoring one theextremities, that is, either for the purpose of energy production or waste reduction. In this thesis, the focus is on waste reduction, that is the slaughter houseresidues. Nevertheless, the ultimate outcome is always to reduce as much waste as possible and, atthe same time, generate profitable energy. There are many technological and financial challenges that have to be addressed to see the completerealization of the biogas concept. Therefore, this master thesis focus on producing biogas fromresidues of slaughter houses in the greater area around Lake Titicaca and studies whichtechnological issues have to be solved. Furthermore, analyzing how the biogas segment can befurther developed in Bolivia according to the appropriate technology selection is alsoinvestigated.

APA, Harvard, Vancouver, ISO, and other styles

8

Mezzullo, William G. "An interdisciplinary assessment of biogas production and the bioenergy potential within the South West of England." Thesis, University of Bath, 2010. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527139.

Full text

Abstract:

There is a growing need to reduce the use of fossil fuels for energy. A twofold reason exists for this: firstly these resources are finite; secondly the utilisation of these resources releases greenhouse gases which are known to contribute towards climate change. The rise in global population and energy use per person is adding to the unsustainable use of fossil fuels. There is the potential to reduce fossil fuel consumption in the South West of England. The region’s abundant natural resources could be used to reduce the overreliance on energy from fossil fuels. A key natural and renewable resource within the region is the availability of biomass. Bioenergy is a form of energy, derived from biomass. Bioenergy has the capability to displace the use of fossil fuels. Additionally, it has the potential to reduce the effect of climate change by absorbing carbon dioxide during the biomass production period. It has the possibility of being integrated into existing infrastructure and is one of the few renewable technologies which can satisfy an array of end-use energy requirements. This thesis highlights a unique method of assessing the potential of bioenergy in the South West of England using a multi appraisal technique. The initial assessment within this thesis has examined the resource availability of bioenergy based on biomass feedstock. Whilst quantifying the overall availability, constraints have been examined to determine the realisable potential of biomass as an energy source. The analysis has then assessed the drivers and barriers of bioenergy development within the region and contextualised this for the UK in general. Following the selection of a single bioenergy pathway (biogas production from anaerobic digestion), the technology has been assessed using a multi appraisal methodology. This methodology has involved the use of net-energy analysis, environmental life cycle assessment and financial investment assessments. The thesis demonstrates that the region has a notable resource availability of biomass. However, a number of barriers to development have been found which could impede the utilisation of this energy source. The selected bioenergy pathway of biogas from anaerobic digestion was found to eliminate some of these barriers. Assessing the potential of biogas using multi appraisal techniques highlighted that this pathway could, in some cases, offer positive environmental, energy and financial benefits.

APA, Harvard, Vancouver, ISO, and other styles

9

Ertem, Funda Cansu. "IMPROVING BIOGAS PRODUCTION BY ANAEROBIC DIGESTION OF DIFFERENT SUBSTRATES : Calculation of Potential Energy Outcomes." Thesis, Högskolan i Halmstad, Ekologi och miljövetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-15944.

Full text

Abstract:

Global energy demand is rapidly increasing. In contrast, fossil fuel reserves are decreasing. Today, one of the major challenge is energy supply for the future. Furthermore, effects of global warming cannot be neglected anymore. Alternative energy sources such as biogas should be developed. The biomass has huge biogas potential. However, arable area in the world is limited. Therefore, substrate which will be used for biogas production should be chosen carefully. The objective of this study was to determine the biogas yields of different substrates. For this reason; red algae, green algae, mixture of brown and red algae, mixture of sugar beets and sugar beet leaves, mixture of straw and sugar beet leaves, mixture of maize and sugar beet leaves, straw, maize and ensiled ley were chosen to conduct a lab-based anaerobic digestion experiment. Biogas production and composition in mesophilic (37 OC) conditions during 25 days were measured and compared. The measurements were performed in a system consisting of 32, 1000 ml glass bottles with rubberstoppers. Potential energy production and energy requirements of each substrate were calculated. Methane yields ranged between 65.8 – 578.9 m3. t-1 VS (Volatile Solids). Whilst the highest methane yield was obtained from sugar beets, the lowest methane yields were obtained from the co-digestion of sugar beets and sugar beet leaves. The highest total energy potential for Sweden was obtained from ensiled ley and the lowest energy potential was obtained from maize. Sugar beet leaves were not good co-substrates, when they were digested with sugar beets, since they resulted in a decline in the methane yields. The highest total energy requirements for cropping and digestion were calculated for sugar beets. The lowest total energy requirements for cropping and digestion were calculated for ensiled ley. In the present study, digestion of sugar beets is suggested as good substrates for biogas production in Sweden, since it is more economical and helpful to solve the food&energy challenge. Although algae did not yield as much biogas as crops, they are interesting for biogas production since algae are considered a problem on the beaches and their high growth rates and abundance make them attractive for use in energy production. Due to lack of information, further studies are needed about economical aspects of algae for using in biogas plants.

APA, Harvard, Vancouver, ISO, and other styles

10

Granato, Eder Fonzar [UNESP]. "Análise de viabilidade técnica e econômica da biodigestão anaeróbia da vinhaça." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/141880.

Full text

Abstract:

Submitted by EDER FONZAR GRANATO null (eder1962granato@gmail.com) on 2016-07-18T15:30:51Z No. of bitstreams: 1 TESE EDER FONZAR GRANATO 1962 com ficha.pdf: 2663771 bytes, checksum: 91f29e8fd5aa752f16fc4d9ab7721195 (MD5)
Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-07-19T20:46:25Z (GMT) No. of bitstreams: 1 granato_ef_dr_bot.pdf: 2663771 bytes, checksum: 91f29e8fd5aa752f16fc4d9ab7721195 (MD5)
Made available in DSpace on 2016-07-19T20:46:25Z (GMT). No. of bitstreams: 1 granato_ef_dr_bot.pdf: 2663771 bytes, checksum: 91f29e8fd5aa752f16fc4d9ab7721195 (MD5) Previous issue date: 2016-05-25
O Brasil produz anualmente 30 bilhões de litros de etanol de cana de açúcar com previsão do Ministério de Minas e Energia de atingir 36 bilhões de litros em 2024. A vinhaça é o resíduo líquido, rico em potássio e matéria orgânica que resulta da destilação do etanol, na proporção de 10 a 15 litros de vinhaça para cada litro de etanol. Disposto indevidamente, pode trazer sérios riscos para o ambiente devido ao alto potencial poluidor. Os estados de São Paulo, Paraná e Mato Grosso do Sul, possuem normas específicas sobre disposição desse resíduo, mas não atingem por completo o objetivo de controlar e mitigar os problemas, pois a disposição final da vinhaça se resume unicamente na fertirrigação sem qualquer outro tratamento. No presente trabalho, realizado no Laboratório de Biomassa do Departamento de Engenharia Rural da Faculdade de Ciências Agrárias e Veterinárias da UNESP de Jaboticabal, analisou-se a biodigestão anaeróbia da vinhaça, caracterizando-se a produção de biogás e a redução do potencial poluidor. Para tanto, foram efetuados estudos de viabilidade técnica da biodigestão anaeróbia da vinhaça analisando os parâmetros: neutralização do pH da vinhaça, utilização do reciclo e estabilização da temperatura da vinhaça. Para os três parâmetros citados foram registrados e analisados dados referentes a: produção de biogás (m3), composição do biogás (% de CH4 e CO2) e redução do potencial poluidor da vinhaça após biodigestão anaeróbia (DQO). No que diz respeito a produção do biogás, os resultados considerados relevantes foram na correção do pH (aumento de 97,5%) e no aquecimento do afluente (aumento de 79%). Em relação a composição do biogás, obteve-se, aumento de 9% de metano redução de 3,6% de dióxido de carbono quando se aquece o afluente. Quando se utiliza reciclo a redução de DQO aumentou em 50% e o aquecimento do afluente permitiu aumentou a redução em 62%, demonstrando a viabilidade técnica do presente estudo. Para se determinar a viabilidade econômica foram efetuados estudos referentes a: Demonstração do Fluxo de Caixa, Valor Presente Liquido, Taxa Interna de Retorno e Payback Descontado. Em relação ao Valor Presente Liquido, o resultado obtido foi de R$ 2.179.331,76, maior que zero. A Taxa Interna de Retorno foi de 8%, maior que 7,5% (Taxa Atrativa Mínima). O retorno do investimento pelo cálculo do Payback Descontado será em 5,54 anos, provando assim que o projeto é viável economicamente.
The Brazil annually produces 30 billion liters of ethanol from sugar cane with the Ministry of Mines and Energy forecast to reach 36 billion liters in 2024. The stillage is the liquid waste, rich in potassium and organic matter resulting from the distillation of ethanol in the proportion of 10 to 15 liters of vinasse per liter of ethanol. Willing improperly, can pose serious risks to the environment due to the high pollution potential. The states of São Paulo, Paraná and Mato Grosso do Sul, have specific rules on disposal of this waste, but do not reach completely in order to control and mitigate the problems because the final disposal of vinasse comes down solely in fertigation without any other treatment . In this study, conducted at the Laboratory of Biomass Department of Rural Engineering of the Faculty of Agricultural and Veterinary Sciences of Jaboticabal UNESP, analyzed the anaerobic digestion of vinasse, characterizing the production of biogas and reduce the pollution potential. Therefore, technical feasibility studies of anaerobic digestion of vinasse were made by analyzing the parameters: pH neutralization of vinasse, use of recycling and stabilization of vinasse temperature. For the three mentioned parameters were recorded and analyzed data for: biogas production (m3), biogas composition (% CH4 and CO2) and reduced pollution potential of vinasse after anaerobic digestion (COD). As regards the production of biogas, the results were considered significant at pH correction (increase of 97.5%) and heating the influent (79% increase). For biogas composition was obtained, an increase of 9% methane 3.6% reduction of carbon dioxide when heated affluent. When COD reduction using recycled increased by 50% and heating affluent allowed increased the reduction by 62%, demonstrating the technical feasibility of this study. To determine the economic feasibility studies were made regarding: Cash Flow Statement, Net Present Value, Internal Rate of Return and Discounted Payback. Regarding the Net Present Value, the result was of R$ 2,179,331.76, greater than zero. The internal rate of return was 8%, higher than 7.5% (rate Attractive Minimum). The return on investment by calculating the Discounted Payback will be 5.54 years, thus proving that the project is economically viable.

APA, Harvard, Vancouver, ISO, and other styles

11

Caille, L'Etienne Thibault. "Potential for Biogas Production from Residues of a Slaughter House at High Altitude in Bolivia." Thesis, KTH, Energi och klimatstudier, ECS, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-62238.

Full text

Abstract:

The potential for biogas production with residues of a slaughter house in the climatic conditions of LaPaz has been determined during the master’s thesis. The project was carried out at a pilot plantconsisting of three tubular biodigesters made of polyethylene. The study showed that there is strong potential for biogas and biofertilizer production from residues ofslaughter houses at high altitude and cold climate in Bolivia, even by using blood which is the majorcomponent responsible of the water contamination. This production led to avoid water contamination,to limit the greenhouse effect by limiting the methane release into the atmosphere due to uncontrolledwaste management, and to improve the agriculture yields through the use of organic fertilizer. After afirst period of investigation, new parameters of operation of the pilot plant were defined in order tooptimize the biogas and biofertilizer production. But the tubular biodigesters made of polyethylenecould difficultly be further developed at industrial scale. Thus the final part of the project consisted in the design of a new type of low-cost pilot plant whichcould solve the environmental burden caused by slaughter houses residues in all Bolivia, whilegenerating more economical benefits from the biogas and biofertilizer production. This pilot plant wasintended to be further scaled-up and developed in all Bolivia if the new investigation carried out afterthe master’s thesis would give satisfactory results. The estimations of industrial plants based on theresults of the pilot plant of Achachicala showed that the slaughter houses could work only by usingbiogas resulting from the anaerobic digestion of their residues, while generating important amounts ofbiofertilizer which would be a source of important economical benefits.

APA, Harvard, Vancouver, ISO, and other styles

12

Gilson, Eoin. "Biogas production potential and cost-benefit analysis of harvesting wetland plants (Phragmites australis and Glyceria maxima)." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-34424.

Full text

Abstract:

Biogas production from energy crops grown on arable land often competes with food and feed production. Wetland plants offer an alternative source of biomass as well as offering a number of environmental benefits such as nutrient removal from wastewaters, carbon sequestration and reducing the use of mineral fertilizer. The aim of this study is to investigate the effect of harvest time on biogas production of Phragmites australis and Glyceria maxima and to perform a cost-benefit analysis of using these wetland plants as a substrate for biogas production. The results of the batch experiment show that the overall biogas production and specific methane yields of biomass harvested in June was higher than biomass harvested in September due the increased lignocellulosic nature of the more mature September plant. The cost-benefit showed that in Sweden it is not currently profitable to solely use wetland plants for biogas production. For both species the highest costs were seen in the June harvested biomass, this was due to the much higher fresh weight and increased transportation costs. For both species the highest revenues generated were the June harvested biomass, this was due to the higher specific methane yields. It was found that the harvest time that was closest to profitability from both species was the June harvest for Phragmites australis. Although the costs were higher for harvesting in June, this was outweighed by the higher amount of electricity produced for this scenario. If transportation distance was to be increased it could result in September being the favourable harvest time. Therefore, individual circumstances of the farmers could decide which is the optimal harvest time. Although solely using wetland plants for biogas production is not currently profitable, co-digestion and pre-treatment are options to investigate that could change this. Also if a greater financial value is put on the socioeconomic benefits such as increased biodiversity, aesthetic value and global warming mitigation it may be financially viable in the future.

APA, Harvard, Vancouver, ISO, and other styles

13

Lönnqvist, Tomas. "Biogas in Swedish transport – a policy-driven systemic transition." Doctoral thesis, KTH, Energiprocesser, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-206578.

Full text

Abstract:

The thesis analyzes the conditions for biogas in the Swedish transport sector. Biogas can contribute to the achievement of Sweden’s ambitious targets of decreased emissions of greenhouse gases and an increased share of renewables in the transport sector, a sector that encompasses the major challenges in the phase-out of fossil fuels. Biogas development has stagnated during recent years and there are several factors that have contributed to this. The use of biogas in transport has developed in niches strongly affected by policy instruments and in this thesis, the progress is understood as a policy-driven systemic transition. Biogas has (started to) become established at the regime level and has begun to replace fossil fuels. The major obstacles for continued biogas development are found to be the stagnated vehicle gas demand, the low predictability of Swedish policy instruments, and electric car development. Moreover, the current prolonged period of low oil prices has also contributed to a lack of top-down pressure. A large share of the cheap and easily accessible feedstock for conventional biogas production is already utilized and an increased use of vehicle gas could enable a commercial introduction of forest-derived methane. However, the technologies to produce forest-derived methane are still not commercial, although there are industrial actors with technological know-how. Future biogas development depends on how the policy framework develops. Policy makers should consider the dynamics of biogas as a young sociotechnical system where different system fronts develop at a varying pace. Currently the demand side is lagging behind. However, it is necessary to maintain predictable policy support throughout the entire biogas value chain, since the system fronts that lag can vary over time. The low predictability of Swedish policy instruments indicates that policy makers should exercise care in their design to create a more robust policy framework moving forward.

QC 20170508

APA, Harvard, Vancouver, ISO, and other styles

14

Forkman, Tova. "Biogaspotential vid samrötningav mikroalger och blandslam från Västerås kommunala reningsverk." Thesis, Sveriges lantbruksuniversitet, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-232954.

Full text

Abstract:

Because of the increasing trends in energy consumption and increased environmental awareness, greater focus has been placed on improvement and development of renewable energy sources. An already proven and accepted method is biogas production from anaerobic digestion at municipal wastewater treatment plants. In the waste water treatment process solid material and dissolved pollutants are separated from the water, forming a sludge. The sludge is separated from the process and stabilized during anaerobic digestion or aerobic aeration. Most often, mesophilic anaerobic digestion is used. Because of degradation by microorganisms, biogas with a high content of methane is formed during the digestion. To optimize the process different studies with co-digestion with sludge and other substrate have been made. It has been showed, in earlier research studies, that co-digestion with microalgae and sewage sludge results in a synergistic effect with increased biogas production. As the microalgae are microorganisms which use photosynthesis they contain stored energy from sun light. The stored energy will be available when the microalgae are digested in mesophilic conditions. In contrast to other biomass suitable for co-digestion microalgae have the advantage of being able to grow in waste water and reduce the pollutants in the water phase. Cultivation of microalgae will therefore not compete with the cultivation of food production and at the same time has the possibility to decrease the electricity- and heat consumption at the wastewater treatment plants. The aim of this study was to investigate how a possible synergetic effect between microalgae and sewage sludge effects the biogas production and the process stability. The microalgae was cultivated in municipal waste water from the WWTP in Umeå (Sweden) and the sludge was collected from the WWTP in Västerås (Sweden). The fermenters used was of the type DOLLY© and the active volume was 5 dm3. The temperature in the fermenters was kept at 37 °C and the study was divided into two periods. During the first period the hydraulic retention time was 15 days and the organic loading rate 2.4 g VS dm-3 d-1. During the second period the hydraulicretention time was kept at 10 days and the organic loading rate was 3.5 g VS dm-3 d-1. The result showed an increase with 54.6 % in methane production per reduced VS in the fermenter with co-digestion compared to the fermenter where only sludge was digested. Period one showed the highest increase. The result also showed a good process stability for both fermenters during the whole experiment. This study shows that there are reasons for continued investigations about co-digestion with microalgae and sewage sludge for an increased biogas production.
På grund av ökande el- och värmeförbrukning och ökat miljöengagemang har större fokus lagts på förbättring och utveckling av förnyelsebara källor för el- och värmeproduktion. En redan beprövad och accepterad metod för framställning av förnyelsebar energi är från biogasproduktion vid kommunala reningsverk. Vid rening av avloppsvatten avskiljs fasta partiklar och lösta föroreningar och bildar ett slam som separeras från vattnet. Slammet kan sedan stabiliseras anaerobt genom rötning eller aerobt genom luftning. En ofta använd metod vid konventionella reningsverk är mesofil anaerob rötning. Vid rötningen bryts material ner av mikroorganismer och genererar biogas som framförallt innehåller metan och koldioxid. För att optimera en sådan process och därmed kunna utvinna mer gas har det tidigare undersökts hur samrötning med olika material påverkar biogasproduktionen. Det har visat sig i forskningsförsök att samrötning med mikroalger och orötat blandslam ger en synergieffekt och mer biogas produceras. Mikroalgerna innehåller lagrad energi från solljus, då de är fotosyntesiserande organismer. Den lagrade energin har visat sig bli tillgänglig vid mesofil anaerob nedbrytning. Till skillnad från annan biomassa som undersökts för samrötning kan mikroalgerna odlas på avloppsreningsverken och fungera som en del av reningsprocessen då mikroalgerna tar upp näringsämnen ur vattnet de växer i. På det sättet undviks konkurrens om odlingsmark för livsmedel och så blir reningsprocessen på avloppsreningsverken mer el- och värmeeffektiv. Syftet med studien var att undersöka om eventuell synergieffekt mellan mikroalgerna och slammet påverkar biogasproduktionen och processtabiliteten vid mesofil anaerob rötning. Mikroalgerna som användes var odlade på mekaniskt renat spillvatten från Umeås reningsverk och slammet som användes hämtades ifrån Västerås reningsverk. Rötkamrarna som användes var av modellen DOLLY© med en aktiv volym på 5 dm3. Temperaturen i rötkamrarna hölls kring 37°C och studien var uppdelad i två perioder. Under period ett var den hydrauliska uppehållstiden 15 dygn och den organiska belastningen 2,4 g VS dm-3 d-1, medan period två hade en hydraulisk uppehållstid på 10 dygn och en organisk belastning på 3,5 g VS dm-3 d-1. Resultaten visade att metangasproduktionen per tillförd mängd organiskt material var lägre vid samrötning jämfört med rötning av enbart slam. Metangasproduktionen per reducerad mängd organiskt material ökade med upp till 54,6 % vid samrötningen jämfört med rötning av enbart slam. Period ett gav upphov till den största ökningen. Processen hölls stabil även vid inblandning av mikroalger, under både period ett och två. Studien visar att det finns ett underlag för fortsatta studier kring samrötning av mikroalger och slam för en ökad biogasproduktion.

APA, Harvard, Vancouver, ISO, and other styles

15

Hedberg, Erika, and Helén Danielsson. "Potential for Absorption Cooling Generated from Municipal Solid Waste in Bangkok : A Comparison between Waste Incineration & Biogas Production with Combustion." Thesis, Linköpings universitet, Industriell miljöteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-57240.

Full text

Abstract:

This master’s thesis has been performed in Bangkok, Thailand at the company Eco Design Consultant Co., Ltd. The aim is to investigate the possibilities to generate absorption cooling from municipal solid waste in the Bangkok area. The investigation includes a comparison between waste incineration and biogas production with combustion to see which alternative is preferable. During the investigation, a Swedish perspective has been used. The research for the report mainly consisted of published scientific articles from acknowledged sources as well as information from different Thai authorities. Also, experts within different areas were contacted and interviewed. In order to determine which of the two techniques (waste incineration or biogas production with combustion) that is best suited to generate absorption cooling, a model was designed. This model involved several parameters regarding e.g. plant efficiency, amount of treated waste and internal heat usage. As for the results of the model, three parameters were calculated: the generated cooling, the net electricity generation and the reduced greenhouse emissions. The overall Thai municipal solid waste generation in Thailand is estimated to approximately 15 million tons per year and the majority of the waste ends up at open dumps or landfills. There are only two to three waste incinerators in the country and a few projects with biogas generation from municipal solid waste. The main electricity is today generated from natural gas which makes the majority of the Thai electricity production fossil fuel based. As for absorption cooling, two applications of this technique has been found in Thailand during the research; one at the Naresuan University and one at the Suvarnabhumi airport in Bangkok. The model resulted in that the best alternative to power absorption cooling technique is waste incineration. This alternative has potential to generate 3200 GWh cooling per year and 1100 GWh electricity per year. Also, this alternative resulted in the largest decrease of greenhouse gas emissions, ‐500 000 tons per year. The model also showed that the same amounts of generated cooling and electricity can never be achieved from biogas production with combustion compared to waste incineration. Regardless, waste incineration has an important drawback: the citizens of Thailand seem to oppose further development of waste incineration in the country. The biogas technique seems more approved in Thailand, which benefits this alternative. Due to the high moisture and organic content in the municipal solid waste, a combination between the two waste handling alternatives is suggested. This way, the most energy can be withdrawn from the waste and the volume of disposed waste is minimized. Our overall conclusion is that the absorption cooling technique has great potential in Thailand. There is an increasing power‐ and cooling demand, absorption cooling generated from either or both of the alternatives can satisfy these demands while reducing greenhouse gas emissions. We also believes that the cost for using absorption cooling has to be lower than for the current compression cooling if the new technique is to be implemented further.

APA, Harvard, Vancouver, ISO, and other styles

16

Abrahamsson, Louise. "Improving methane production using hydrodynamic cavitation as pre-treatment." Thesis, Linköpings universitet, Tema Miljöförändring, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-128783.

Full text

Abstract:

To develop anaerobic digestion (AD), innovative solutions to increase methane yields in existing AD processes are needed. In particular, the adoption of low energy pre-treatments to enhance biomass biodegradability is needed to provide efficient digestion processes increasing profitability. To obtain these features, hydrodynamic cavitation has been evaluated as an innovative solutions for AD of waste activated sludge (WAS), food waste (FW), macro algae and grass, in comparison with steam explosion (high energy pre-treatment). The effect of these two pre-treatments on the substrates, e.g. particle size distribution, soluble chemical oxygen demand (sCOD), biochemical methane potential (BMP) and biodegradability rate, have been evaluated. After two minutes of hydrodynamic cavitation (8 bar), the mean fine particle size decreased from 489- 1344 nm to 277- 381 nm (≤77% reduction) depending of the biomasses. Similar impacts were observed after ten minutes of steam explosion (210 °C, 30 bar) with a reduction in particle size between 40% and 70% for all the substrates treated. In terms of BMP value, hydrodynamic cavitation caused significant increment only within the A. nodosum showing a post treatment increment of 44% compared to the untreated value, while similar values were obtained before and after treatment within the other tested substrates. In contrast, steam explosion allowed an increment for all treated samples, A. nodosum (+86%), grass (14%) and S. latissima (4%). However, greater impacts where observed with hydrodynamic cavitation than steam explosion when comparing the kinetic constant K. Overall, hydrodynamic cavitation appeared an efficient pre-treatment for AD capable to compete with the traditional steam explosion in terms om kinetics and providing a more efficient energy balance (+14%) as well as methane yield for A. nodosum.
Det behövs innovativa lösningar för att utveckla anaerob rötning i syfte att öka metangasutbytet från biogassubstrat. Beroende på substratets egenskaper, kan förbehandling möjliggöra sönderdelning av bakterieflockar, uppbrytning av cellväggar, elimination av inhiberande ämnen och frigörelse av intracellulära organiska ämnen, som alla kan leda till en förbättring av den biologiska nedbrytningen i rötningen. För att uppnå detta har den lågenergikrävande förebehandlingsmetoden hydrodynamisk kavitation prövats på biologiskt slam, matavfall, makroalger respektive gräs, i jämförelse med ångexplosion. Effekten på substraten av dessa två förbehandlingar har uppmäts genom att undersöka distribution av partikelstorlek, löst organiskt kol (sCOD), biometan potential (BMP) och nedbrytningshastigheten. Efter 2 minuters hydrodynamisk kavitation (8 bar) minskade partikelstorleken från 489- 1344 nm till 277- 281 nm (≤77 % reduktion) för de olika biomassorna. Liknande påverkan observerades efter tio minuters ångexplosion (210 °C, 30 bar) med en partikelstorlekreducering mellan 40 och 70 % för alla behandlade substrat. Efter behandling med hydrodynamisk kavitation, i jämförelse med obehandlad biomassa, ökade metanproduktionens hastighetskonstant (K) för matavfall (+65%), makroalgen S. latissima (+3%), gräs (+16 %) samtidigt som den minskade för A. nodosum (-17 %). Förbehandlingen med ångexplosion ökade hastighetskonstanten för S. latissima (+50 %) och A. nodosum (+65 %) medan den minskade för gräs (-37 %), i jämförelse med obehandlad biomassa. Vad gäller BMP värden, orsakade hydrodynamisk kavitation små variationer där endast A. nodosum visade en ökning efter behandling (+44 %) i jämförelse med obehandlad biomassa. Biomassa förbehandlade med ångexplosion visade en ökning för A .nodosum (+86 %), gräs (14 %) och S. latissima (4 %). Sammantaget visar hydrodynamisk kavitation potential som en effektiv behandling före rötning och kapabel att konkurrera med den traditionella ångexplosionen gällande kinetik och energibalans (+14%) samt metanutbytet för A. nodosum.

APA, Harvard, Vancouver, ISO, and other styles

17

Flad, Veronika [Verfasser], Johann [Akademischer Betreuer] Bauer, Wolfgang [Gutachter] Liebl, and Johann [Gutachter] Bauer. "Anaerobic fungi – detection methods, fate in agricultural biogas plants and potential to improve gas production / Veronika Flad ; Gutachter: Wolfgang Liebl, Johann Bauer ; Betreuer: Johann Bauer." München : Universitätsbibliothek der TU München, 2020. http://d-nb.info/1220320919/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Liu, Yang. "Greenalgae as a substrate for biogas production - cultivation and biogas potentials." Thesis, Linköping University, Linköping University, Department of Water and Environmental Studies, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-57987.

Full text

Abstract:

Algae is regarded as a good potential substrate for biogas production, due to high cells productivity, low cellulose and zero lignin content. Two parts were included in this study: first, cultivations of micro-algae (Chlorella sorokiniana and Tetraselmis suecica) at two different nitrate concentrations, also the effect of addition of CO₂ on algae grow was investigated in this first part. Second, batch fermentations of the cultivated micro-algae as well as a powder Chlorella (obtained from Raw Food Shop) and a dry mix filamentous algae (collected in the pounds in the park at the back of the Tema-building and then dried) were performed. In this part also effects of thermo-lime pretreatment (room temperature, 80^oC, 105^oC and 120^oC) on the algae biogas potentials was investigated.

Both strains of micro-algae cultured at low nitrate gave more CH₄ yield: 319 (±26) mL and 258 (±12) mL CH₄per added gVS was obtained during the degradation of Chlorella sorokiniana grown at 0.4mM-N and 2mM-N level, respectively. For Tetraselmis suecica 337 (±37) mL and 236 (±20) mL CH₄ per added gVS was obtained at 2.4mM-N and 12mM-N level, respectively. Powder Chlorella gave the highest biogas production (719 ±53 mL/added gVS) and CH₄ yields (392 ±14 mL/added gVS), followed by the dry filamentous algae (661 ±20 mL biogas and 295 ±9 mL CH₄ per added gVS) and Tetraselmis suecica (12 mM-N; 584 ±7 mL biogas and 295 ±9 mL CH₄ per added gVS).

A negative effect of lime treatment at room temperature on CH₄ yield of algal biomass was obtained. Lime treatment at 120^oC showed the fastest degradation rate for Tetraselmis suecica and powder Chlorella during the initial 5 days of incubation.

Chlorella sorokiniana and Tetraselmis suecica cultures flushed with biogas containing 70% and also CO₂ enriched air (5% CO₂) did not increase cells growth (measured as OD₆₀₀) if compared to references grown under air. On the contrary, a clearly inhibition effect on the algal cells growth was observed in some cultures.

APA, Harvard, Vancouver, ISO, and other styles

19

Longo, Rodrigo Rodrigues. "Geração de metano em reator UASB: avaliação de parâmetros de monitoramento para controle do processo de tratamento anaeróbio de vinhaça." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-13082015-102042/.

Full text

Abstract:

Com o propósito de explorar o potencial de geração de metano a partir de vinhaça de cana-de-açúcar e propor procedimentos de controle do processo anaeróbio, foi utilizado um reator UASB (Upflow Anaerobic Sludge Blanket) em escala piloto, equipado de separador gás-sólido-líquido modificado e sem recirculação de efluente. A unidade foi inoculada com lodo granular e utilizou-se substrato concentrado (DQO de 20 g.L-1) para sua alimentação. O reator foi submetido a cargas orgânicas volumétricas (COV) de 0,7 a 7 KgDQO.m-3.d-1, durante 300 dias de operação. O procedimento operacional baseou-se no aumento de carga por escalonamento da vazão de alimentação em função da manutenção de variação inferior a 10% para a eficiência do sistema. Para o tamponamento da vinhaça de alimentação, no início da operação utilizou-se 1g NaHCO3.g-1DQOafluente, com redução gradativa até 0,125g NaHCO3.g-1DQOafluente. O monitoramento do desempenho do processo anaeróbio se deu pela avaliação dos parâmetros: eficiência de remoção de DQO, pH, alcalinidade, ácidos voláteis, razão alcalinidade intermediária/alcalinidade parcial, razão Prop:Ac, vazão de metano e porcentagem de metano no biogás. O reator UASB apresentou valor médio de eficiência de remoção de DQO de 92±4,4%, para cargas aplicadas entre 0,7 e 4,8 KgDQO.m-3.d-1. A maior produção média de metano observada durante o período operacional foi 5 m3CH4.m-3 de vinhaça aplicada para cargas orgânicas entre 4,1 e 5,6 KgDQO.m-3.d-1. A produção de biogás apresentou valor médio de metano de 70±7% para 1 a 5,6 Kg DQO.m-3.d-1. A operação do reator com cargas aplicadas acima de 5,6 KgDQO.m-3.d-1 gerou menor produção de biogás, redução na porcentagem de metano e aumento da carga de ácidos voláteis efluente, assim como queda na eficiência de remoção de DQO. Devido ao acréscimo de carga (0-2 para 4-6 KgDQO.m-3.d-1), a variação da concentração para cada tipo de ácido foi: acético (56±70 para 216±121 mg.L-1), propiônico (26±28 para 165±150 mg.L-1) e butírico (4±7 para 60±18 mg.L-1). Notou-se que a relação entre as concentrações de ácido propiônico e ácido acético (razão Prop:Ac) pode ser utilizada como parâmetro de monitoramento da estabilidade do reator. A elevação de COV de 3,9 a 6,4 KgDQO.m-3.d-1acarretou alteração na razão Prop:Ac de 0,8 a 1,75, corroborando descontroles do processo anaeróbio associado à queda de eficiência na geração de metano.
In order to explore the potential of methane generation from sugarcane vinasse and propose procedures for the anaerobic process control, was utilized a pilot scale UASB reactor (Upflow Anaerobic Sludge Blanket), equipped with modified gas-solid-liquid separator and without recirculation of effluent. The unit was inoculated with granular sludge and concentrated substrate was used (COD 20 g.L-1) for feeding. The reactor was submitted to volumetric organic load (VOL) from 0.7 to 7 KgCOD.m-3.d-1, during 300 days of operation. The reactor operation was based on the increase of load by staggering the feed flow in function of the maintenance of variation lower than 10% for the system efficiency. For buffering the feedings vinasse was used 1g NaHCO3.g-1CODinfluent at the beginning of the operation, with gradual reduction to the value of 0.125 g NaHCO3.g-1CODinfluent. The monitoring of the anaerobic process performance was due to the evaluation of the following parameters: efficiency of COD removal pH, alkalinity, intermediate alkalinity/partial alkalinity ratio; Prop:Ac ratio, methane flow and percentage of methane in the biogas. The UASB reactor demonstrated a COD average removal efficiency of 92±4.4%, to applied loads between 0.7 and 4.8 KgCOD.m-3.d-1. The highest average methane production observed during the operational period was 5 m3CH4.m-3 of vinasse applied for organic loads between 4.1 and 5.6 KgCOD.m-3.d-1. The biogás production demonstrated a methane average of 70±7% for 1 to 5.6 KgCOD.m-3.d-1. The reactor operation with loads up to 5.6 KgCOD.m-3.d-1 caused lower production of biogas, reduction in the percentage of methane and increase for effluent volatile acids load, as well as decrease of COD removal efficiency. Due to the additional load (0-2 to 4-6 KgCOD.m-3.d-1), the change in concentration for each type of acid was: acetic acid (56±70 to 216±121 mg.L-1), propionic acid (26±28 to 165±150 mg.L-1) and butyric acid (4±7 to 60 ± 18 mg.L-1). It was noted that the relationship between the concentrations of propionic acid and acetic acid (ratio Prop:Ac) may be used as a monitoring parameter of the reactor stability. The increase in VOL of 3.9 to 6.4 KgCOD.m-3.d-1 caused change in the Prop:Ac ratio of 0.8 to 1.75, confirming the upsets on the anaerobic process associated with efficiency drop in methane generation.

APA, Harvard, Vancouver, ISO, and other styles

20

Poudel, Bishnu Chandra. "Carbon Balance Implications Of Forest Biomass Production Potential." Doctoral thesis, Mittuniversitetet, Avdelningen för ekoteknik och hållbart byggande, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-22075.

Full text

Abstract:

Forests in boreal and temperate forest-ecosystems have an important function since they sequester atmospheric carbon by uptake of carbon-dioxide in photosynthesis, and transfer and store carbon in the forest ecosystem. Forest material can be used for bio-fuel purposes and substitute fossil fuels, and supply wood products, which can replace carbon- and energy-intensive materials. Therefore it is vital to consider the role of forests regarding today´s aim to mitigate climate change. This thesis assess (i) how climate change affects future forest carbon balance, (ii) the importance of different strategies for forest management systems, and biomass production for the carbon balance, (iii) how the use of forest production affect the total carbon balance in a lifecycle perspective, and (iv) how the Swedish carbon balance is affected from the standpoint of both the actual use of forest raw material within Sweden and what Swedish forestry exports. The analysis was made mainly in a long-term perspective (60-300 year) to illustrate the importance of temporal and also the spatial perspective, as the analysis includes stand level, landscape level, and national level. In this thesis, forestry was considered a system. All activities, from forest regeneration to end use of forest products, were entities of this system. In the evaluation, made from a systems perspective, we used life-cycle analysis to estimate carbon stock in different system flows. Different forest management systems and forest production were integrated in the analyses. Different forest management scenarios were designed for the Swedish forest management in combination with the effect of future climate change; (i) intensive forest practice aiming at increased growth, (ii) increased forest set-aside areas, changes in forest management systems for biomass production, and (iii) how the use of forest production affect the total carbon balance (construction material, bioenergy and other domestic use). The results showed that future climate changes and intensive forest management with increased production could increase the biomass production and the potential use of forest raw material. This has a positive effect on carbon storage for the forest carbon stock, litter production and carbon storage in the ground etc. and help mitigating carbon-dioxide. Increased forest set-aside areas can increase the short-term carbon stock in forest ecosystems, but will reduce the total long-term carbon balance. The net carbon balance for clear-cut forestry did not differ significantly from continuous-cover forestry, but was rather a question of level of growth. Most important, in the long term, was according to our analysis, how forest raw material is used. Present Swedish forestry and use of forest raw material, both within Sweden and abroad, reduce carbon-dioxide emissions and mitigate climate change. The positive effect for the total carbon balance and climate benefit take place mostly abroad, due to the Swedish high level of export of wood products and the higher substitution effects achieved outside Swedish borders. One strategy is to increase production, harvest and change the use of Swedish forest raw material to replace more carbon intensive material, which can contribute to significant emission reduction. Carbon-dioxide mitigation, as a result of present Swedish forestry, was shown to be almost of the same level as the total yearly emission of greenhouse gases. The total carbon benefit would increase if the biomass production and felling increased and if Swedish wood products replaced carbon intensive materials.This thesis shows also that, by changing forest management, increase the growth and the use of forest raw material and export of forest material we can contribute to even larger climate benefits. In a long-term perspective, the substitution effects and replacement of carbon- and energy-intensive materials are of greater significance than carbon storage effects in forests. A more production oriented forestry needs to make balances and increase the prerequisite for biological diversity, improve recreation possibilities, and protect sensitive land areas and watersheds.Climate benefits, from Swedish forestry, are highly dependent on policy decision-making and how that can steer the direction for the Swedish forestry.

APA, Harvard, Vancouver, ISO, and other styles

21

Groode, Tiffany Amber 1979. "Biomass to ethanol : potential production and environmental impacts." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43144.

Full text

Abstract:

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.
Includes bibliographical references.
This study models and assesses the current and future fossil fuel consumption and greenhouse gas impacts of ethanol produced from three feedstocks; corn grain, corn stover, and switchgrass. A life-cycle assessment approach with an integrated Monte Carlo uncertainty analysis is applied to each of these three bioethanol pathways. Incorporating a Monte Carlo uncertainty analysis within a life-cycle model enables one to account for system variability within the agricultural, technological, and geographic arenas. This results in a range of energy and greenhouse gas impacts rather than previous single-valued estimates. This uncertainty analysis brings greater clarity to the ethanol debate through evaluating the probability of previously published life-cycle assessment net energy results, from reports such as Farrell, Wang, Shapouri, and Pimentel. Lifecycle assessment net energy results show corn grain ethanol to have a positive value when DDGS coproducts are included within the assessment boundary and a slightly negative value when they are not. The system net energy value and GHG emissions are also sensitive to system input assumptions and geographic location. For lignocellulosic ethanol produced from corn stover and switchgrass, a positive net energy value and reduced GHG emissions are seen when compared to gasoline. In addition to net energy results and system GHG emissions, the petroleum displacement and land use impacts for an expanding and evolving ethanol industry are also evaluated.Corn grain, corn stover, and switchgrass-based ethanol potential production levels are also analyzed. It was determined that 55-65 billion liters per year of corn grain ethanol could potentially be produced in the next 10 years, consuming 30% of future US corn grain production. Corn stover and switchgrass have the potential to produce 25-35 and 10-20 billion liters per year of ethanol, respectively.
(cont) These ethanol production results were then applied to assess the feasibility and environmental impact of achieving the new Renewable Fuels Standard, of producing 136 billion liters of renewable fuels by 2022. This study concluded that while the scale is potentially feasible from these three feedstocks, the timeline to achieve this scale would be very challenging given the cellulosic ethanol technological and economic advances that are still needed.
by Tiffany A. Groode.
Ph.D.

APA, Harvard, Vancouver, ISO, and other styles

22

Poudel, Bishnu Chandra. "Forest biomass production potential and its implications for carbon balance." Licentiate thesis, Mittuniversitetet, Institutionen för teknik och hållbar utveckling, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-17281.

Full text

Abstract:

An integrated methodological approach is used to analyse the forest biomass production potential in the Middle Norrland region of Sweden, and its use to reduce carbon emissions. Forest biomass production, forest management, biomass harvest, and forest product use are analyzed in a system perspective considering the entire resource flow chains. The system-wide carbon flows as well as avoided carbon emissions are quantified for the activities of forest biomass production, harvest, use and substitution of non-biomass materials and fossil fuels. Five different forest management scenarios and two biomass use alternatives are developed and used in the analysis. The analysis is divided into four main parts. In the first part, plant biomass production is estimated using principles of plant-physiological processes and soil-water dynamics. Biomass production is compared under different forest management scenarios, some of which include the expected effects of climate change based on IPCC B2 scenario. In the second part, forest harvest potentials are estimated based on plant biomass production data and Swedish national forest inventory data for different forest management alternatives. In the third part, soil carbon stock changes are estimated for different litter input levels from standing biomass and forest residues left in the forest during the harvest operations. The fourth and final part is the estimation of carbon emissions reduction due to the substitution of fossil fuels and carbon-intensive materials by the use of forest biomass. Forest operational activities such as regeneration, pre-commercial thinning, commercial thinning, fertilisation, and harvesting are included in the analysis. The total carbon balance is calculated by summing up the carbon stock changes in the standing biomass, carbon stock changes in the forest soil, forest product carbon stock changes, and the substitution effects. Fossil carbon emissions from forest operational activities are calculated and deducted to calculate the net total carbon balance.The results show that the climate change effect most likely will increase forest biomass production over the next 100 years compared to a situation with unchanged climate. As an effect of increased biomass production, there is a possibility to increase the harvest of usable biomass. The annual forest biomass production and harvest can be further increased by the application of more intensive forestry practices compared to practices currently in use. Deciduous trees are likely to increase their biomass production because of climate change effects whereas spruce biomass is likely to increase because of implementation of intensive forestry practices.IIIntensive forestry practices such as application of pre-commercial thinning, balanced fertilisation, and introduction of fast growing species to replace slow growing pine stands can increase the standing biomass carbon stock. Soil carbon stock increase is higher when only stem-wood biomass is used, compared to whole-tree biomass use. The increase of carbon stocks in wood products depends largely on the magnitude of harvest and the use of the harvested biomass. The biomass substitution benefits are the largest contributor to the total carbon balance, particularly for the intensive forest management scenario when whole-tree biomass is used and substitutes coal fuel and non-wood construction materials. The results show that the climate change effect could provide up to 104 Tg carbon emissions reduction, and intensive forestry practices may further provide up to 132 Tg carbon emissions reduction during the next 100 years in the area studied.This study shows that production forestry can be managed to balance biomass growth and harvest in the long run, so that the forest will maintain its capacity to increase standing biomass carbon and provide continuous harvests. Increasing standing biomass in Swedish managed forest may not be the most effective strategy to mitigate climate change. Storing wood products in building materials delays the carbon emissions into the atmosphere, and the wood material in the buildings can be used as biofuel at the end of a building life-cycle to substitute fossil fuels.These findings show that the forest biomass production potential in the studied area increases with climate change and with the application of intensive forestry practices. Intensive forestry practice has the potential for continuous increased biomass production which, if used to substitute fossil fuels and materials, could contribute significantly to net carbon emissions reductions and help mitigate climate change.

APA, Harvard, Vancouver, ISO, and other styles

23

Williams, Anthony T. "The potential for the production of energy from biomass in South Africa." Thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/26094.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Anastasakis, Konstantinos. "The potential of the production of fuels and chemicals from marine biomass." Thesis, University of Leeds, 2011. http://etheses.whiterose.ac.uk/4167/.

Full text

Abstract:

The need for sustainability, energy security and reduction of global warming has brought many alternative energy sources into the foreground. Already there are well established technologies that can produce renewable energy but when it comes to the production of renewable liquid fuels and chemicals, biomass is the primary feedstock. Biomass is a renewable source of energy that can provide heat, electricity and transport fuels. However, utilisation of biomass posses some limitations such as land availability and competition of energy crops with food crops. In order to overcome these problems "third generation" biofuels from alternative feedstock such as macro-algae have recently come into the foreground. Oceans and seas cover over 70% of the earth's surface, most of which is under exploited, resulting in additional potential for biomass production. This thesis concentrates on the potential for production of bio-energy and chemicals from macro-algae through thermochemical processes such as pyrolysis, combustion and hydrothermal liquefaction. Utilisation of aquatic biomass for production of bioenergy is a very recent concept and there is a lack of information on their thermochemical behaviour. This investigation contributes to a wider study and forms part of the Supergen II bionergy programme investigating the potential for utilisation of macrolage in the UK. This investigation includes a detailed characterisation of the fuel properties and thermal behaviour of a range of wild seaweeds around the UK provided by the Scottish Association of Marine Sciences. In addition, a range of model biochemical components have been investigated, in particular, the model carbohydrates present in macro-algae. Alginic acid, mannitol, laminarin, fucoidan and cellulose are the main carbohydrates present in brown macro-algae. The rest of the plant material comprises of protein and ash. Freshly harvested macro-algae contain 80-90wt% moisture. Their ash content is high, reflecting their high inorganic content. Potassium is the most abundant metal present in macro-algae although other metals are also present including sodium, calcium, magnesium, Their carbohydrate, protein and ash content undergo a seasonal variation during their growth cycle. This variation was found to affect their properties as fuel. Carbon content reaches its maximum during summer - early autumn. During the same period, the inorganic (and thus ash) content is at its minimum suggesting summer - early autumn as the optimum period for harvesting macro-algae for bioenergy. The high carbon and low inorganic content during this period is reflected in its higher heating value but it is still relatively low (13-14 MJ/kg) when compared with terrestrial biomass. The nature of the inhabitant location was found to significantly influence macro-algae fuel properties with samples grown in the open ocean having better fuel properties (higher HHV and lower inorganic content) than samples growing in canals and estuaries. Investigation of the pyrolysis behaviour was performed using thermal analysis such as TGA and Py-GC/MS. The volatile matter evolved during pyrolysis was higher for samples collected during summer and early spring due to their higher carbon content. The main volatiles evolved during decomposition were found to originate either from their carbohydrates or from their protein content. Specific marker compounds were identified for the carbohydrates such as dianhydromannitol, 1-(2-furanyl)-ethanone, 2-hydroxy-3-methyl-2-cyclopenten-1-one and furfural for manitol, laminarin and alginic acid respectively. Proteins are found to produce a range of indoles and pyrroles. Some of the compounds identified may have industrial applications indicating the possibility of producing chemicals through pyrolysis of macro-algae. The high moisture content of seaweed necessitates that significant amounts of water must be removed before this feedstock can be converted by pyrolysis. The high moisture content is similary an issue for combustion which has been assessed by a combination of TGA and characterisation of the biomass. Macro-algae have a low HHV, high halogen content and high ash content and are predicted to have high slagging and fouling behaviour in conventional combustion chambers. This fouling behaviour is predicted through empirical indexes such as the alkali index and is shown to be higher than terrestrial biomass even during summer - early autumn when their inorganic content is at minimum. Typical ash contents vary from 18 to 45wt% and contain mainly oxides of K20, Na2O, CaO and MgO. Pre-treatment prior to combustion can significantly reduce the ash content leading to improved combustion properties, but this also leads to removal of some biochemical components. Using an acid pre-treatment, some of the seaweed's biopolymers, such as mannitol or fucoidan, can be removed presenting the possibility for acquiring valuable chemicals from seaweed before combustion of the residue. An alternative processing route, capable of processing wet feedstocks called hydrothermal liquefaction (HTL) involves the processing of the macro-algae in subcritical water. HTL converts the starting material into four product streams including a bio-crude, a char, an aqueous stream consisting primarily of process water and a gaseous stream. A parametric study of HTL has been investigated using high pressure batch reactors with or without the presence of catalysts. The bio-crude produced from the liquefaction of macrolgae was found to have a high heating value and resembling chemical composition to crude-oil. It can be used directly as a fuel however it still contains significantly high nitrogen levels and will required suitable upgrading (e. g. denitrogenation). The bio-char was found to also have a high heating value. Both bio-crude and bio-char produced from HTL are virtually free of alkali metals suggesting they are suitable for combustion. Reaction conditions such as temperature and the ratio of biomass to water have the greatest influence on product yields and properties. Typical bio-crude yields were in the range of 10 to 19wt% on a daf basis with their HHVs ranging from 32 to 38 MJ/kg. The yields of bio-chars were in similar range (IOwt% to 19wt% on a db) with HHVs between 10 and 26 MJ/kg. An energy balance was calculated in order to investigate the energy required to heat the mixture of macro-algae and water. The energy recovery in the bio-crude and bio-char was relatively low, between 50 and 65%, indicating that a significant portion of the energy content of macro-algae is passing in to the other product streams. The aqueous phase (process water) was found to be rich in metals, especially alkali metals, and sugars, and its composition suggests it maybe possible to utilize it as a fertilizer. A fraction of the sugars present in macro algae (mannitol and laminarin) pass in to the aqueous stream, suggesting there is also potential for fermentetion to bioethanol. The gaseous stream is composed mainly of CO2, N, CO and lower concentrationso H and CH4. The most suitable thermochemical processing route for macro-algae is proposed to be hydrothermal liquefaction and has potential for utilization of all the product streams producing fuels and chemicals using a bio-refinery concept.

APA, Harvard, Vancouver, ISO, and other styles

25

Adesanya, Victoria Oluwatosin. "Investigation into the sustainability and feasibility of potential algal-based biofuel production." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708126.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Adebayo, Adebola B. "Pretreatments and energy potentials of Appalachian hardwood residues for biofuel production." Morgantown, W. Va. : [West Virginia University Libraries], 2010. http://hdl.handle.net/10450/10928.

Full text

Abstract:

Thesis (Ph. D.)--West Virginia University, 2010.
Title from document title page. Document formatted into pages; contains viii, 98 p. : ill. (some col.), col. map. Includes abstract. Includes bibliographical references.

APA, Harvard, Vancouver, ISO, and other styles

27

Ali, Wael. "Modelling of Biomass Production Potential of Poplar in Short Rotation Plantations on Agricultural Lands of Saxony, Germany." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1237199867841-24821.

Full text

Abstract:

The interest in renewables for energy has increased in the last 2-3 decades because of the negative environmental impact caused by the burning of fossil fuels, the raising prices of traditional fuels, the dependence on foreign oil, and the decrease in fossil fuels resources. Biomass energy represents one of the most promising alternatives. Many studies worldwide were devoted to investigate growth and yield of short rotation forestry plantations for energetic use and several empirical and process-based models were developed to predict the potential production of biomass. The current work was concentrated on modelling site productivity (potential of biomass production) of specific poplar clones planted on arable Saxon land under different stocking densities. Empirical data collected from several experimental areas were used. Site productivity has been predicted depending on stand age and site variables using a two-step model. In step one age and site variables were used to model stand dominant height and in step two the constructed dominant height was involved with stocking density to predict stand oven dried biomass. Depending on data availability the model was parameterized for four different groups of poplar clones: Androscoggin (clone Androscoggin), Matrix (Matrix and hybrid 275), Max (Max 1 …Max 5) and Münden (clone Münden). Both stand dominant height and stand dry biomass were modelled for ages 2 – 9 years for clone groups: Matrix and Max and for ages 2 – 7 years for clone groups: Androscoggin and Münden. The model has been tested and validated using several statistical and graphical methods. The relative bias (ē %) in the dominant height estimates ranged between 0.5 % > ē % > - 0.5 % in all clone groups and had a maximum bias of 10.41 % in stand biomass estimates. Model accuracy (mx %) in the dominant height estimates ranged between 12.25 and 17.56 % and between 8.05 and 27.32 % in stand biomass estimates. Two different scenarios were presented to show the potential of biomass that can be produced from poplar plantations on arable and former fallow Saxon lands at different stocking densities. ArcGIS has been used to visualize model application results. In order to produce a mean annual increment ≥ 8 [dry t/ha/a] from poplar plantations (Max group) for more than 50 % of arable or former fallow lands in the first rotation at least 9 years are required under stocking density of 4000 stems/ha and 7 years for both stocking densities 8333 and 10,000 stems/ha
Die Nachfrage nach Holz für energetische Zwecke nimmt in Deutschland und ganz Europa zu. Um diesen Bedarf künftig besser befriedigen zu können, müssen verstärkt Ressourcen aus verschiedenen Quellen wie z. B. Holz aus Niederwäldern oder Durchforstungsreserven im Hochwald mobilisiert und ergänzend Holz in Kurzumtriebsflächen produziert werden (Guericke, M. 2006). Ziel dieser Arbeit war es, das Ertragspotential von Pappelklonen in Kurzumtriebsplantagen unterschiedlicher Baumdichte auf sächsischen Ackerflächen zu untersuchen. Hierzu wurden die potentiellen Erträge anhand empirischer, auf verschiedenen Versuchsflächen erhobener Daten modelliert. Zur Schätzung des Ertragspotentials wurde ein zweistufiges Modell entwickelt: Im ersten Schritt erfolgte die Modellierung der Oberhöhe eines Bestandes (ho, m) in Abhängigkeit von Bestandesalter und Standortfaktoren unter Verwendung einer multiplen linearen Regressionsanalyse, dabei wurden Bestimmtheitsmaße (R²) von 0,975 bis 0,989 erreicht. In einem zweiten Schritt lässt sich dann der Biomassevorrat [tatro/ha/a] mittels nichtlinearer Regressionsanalyse durch die Bestandesoberhöhe schätzen. Das Bestimmtheitsmaß von R² ≥ 0,933 weist auch hier auf eine hohe Anpassungsgüte hin. Die Modellparametrisierung erfolgte für folgende vier Gruppen von Pappelklonen: • Max-Gruppe: Klone Max 1, Max 2, Max 3, Max 4 und Max 5, Altersbereich 2 – 9 Jahre, Baumdichten von 1150 – 13000 Stämmen/ha; • Matrix-Gruppe: Klon Matrix und Hybride 275, Altersbereich 2 – 9 Jahre, Baumdichte 1550 Stämme/ha; • Androscoggin-Gruppe: Klon Androscoggin, Altersbereich 2 – 7 Jahre, Baumdichte 1550 Stämme/ha; und • Münden-Gruppe: Klon Münden, Altersbereich 2 – 7 Jahre, Baumdichte 1550 Stämme/ha. Die Güte des Modells wurde mit Hilfe verschiedener statistischer Verfahren überprüft. Bei der Validierung anhand des Datensatzes, welcher für die Modellkonstruktion Verwendung fand, zeigte das Modell eine Verzerrung bzw. einen Bias von 0,5 % > ē % > - 0,5 % bei der Bestandesoberhöhenschätzung und einen maximalen Bias von 10,41 % bei der Schätzung der Bestandesbiomasse. Die Treffgenauigkeit (mx %) des Modells hingegen variierte zwischen 12,25 % und 17,56 % bzw. 8,05 und 27,32 % (bei Schätzung der Bestandesoberhöhe bzw. der Bestandesbiomasse). Zudem wies das Modell keinen systematischen Fehler zwischen den geschätzten und den realen Werten auf. Bei der Validierung mit einem unabhängigen Datensatz betrug die Treffgenauigkeit (mx %) für die Schätzung der Bestandsoberhöhe und des Biomassevorrates 15,72 bzw. 26,68 %. Um das Ertragspotenzial von Pappelplantagen für die gesamte sächsische Ackerfläche bzw. die gesamte ehemalige Stilllegungsfläche zu bestimmen, wurden die zu Schätzung erforderlichen Standortvariablen auf Gemeindebasis kalkuliert, mittels ArcGIS dargestellt sowie Simulationsrechungen für verschiedene Bestandsdichten vorgenommen und ebenfalls visualisiert. Den Ergebnissen der Simulationsrechnungen zufolge wäre bei einer Stammzahl von 4000 N/ha eine Rotationslänge von 9 Jahren, bei 8333 bis 10.000 N/ha von 7 Jahren erforderlich, um einen durchschnittlichen Gesamtzuwachs (dGz) von ≥ 8 [tatro/ha/a] auf mehr als 50 % der sächsischen Ackerflächen bzw. ehemaligen Stilllegungsflächen in erster Rotation zu erreichen. Würde die gesamte ehemalige sächsische Stilllegungsfläche mit einer Baumdichte von 10.000 Stämmen/ha bepflanzt werden, könnten Pappelplantagen im Alter 9 einen dGz von 520.000 [tatro/a] (entsprechend 250.000 Kubikmeter Diesel) erreichen. Bei Bestockung aller sächsischen Ackerflächen würde sich der Ertrag auf bis zu 9.087.000 [tatro/a] (entsprechend 4.367.000 Kubikmeter Diesel) erhöhen

APA, Harvard, Vancouver, ISO, and other styles

28

Ho, Ai Ling. "Production and purification of xylooligosaccharides from novel plant biomass (Elaeis guineensis Jacq.) and their prebiotic potential." Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.632859.

Full text

Abstract:

The aim of this study was to use a low commercial value by-product of the oil palm industry as an oligosaccharide source, identifying in the process those molecular weights that would have the highest prebiotic efficacy. Oil palm empty fruit bunches (OPEFB) fibre were subjected to autohydrolysis to obtain oligosaccharide-rich liquor. The processed liquor was characterised to determine the operational conditions required to produce the highest xylooligosaccharide (XOS) concentration. Two different purification techniques were employed to remove the monosaccharides and non-saccharide compounds present in the liquor: gel filtration chromatography (GFC) and sequential charcoal adsorption and ultrafiltration. With GFC purification, six mixed XOS fractions with different average degree of polymer is at ion (avDP 4, 7,14,28,44,64) were obtained. The effect of avDP on the human faecal microbiota was determined in vitro, in pH controlled batch cultures using XOS as the main carbohydrate source. The most favourable fermentation profiles were observed with the lower avDP fractions (4, 7, and 14) which showed the highest selectivity for bifidobacteria. A broader DP distribution of XOS fraction with an avDP 9, obtained through ultrafiltration, was further tested in a three stage continuous culture system. The findings suggest that XOS is a potential prebiotic that combines the benefits of increasing health-associated bacteria in the vessel 3 of the model system that simulates the distal colon and reducing proteolysis therein with butyrate production, a metabolite that plays a central role in the regulation of colonic cell proliferation, differentiation and modulation of gene expression.

APA, Harvard, Vancouver, ISO, and other styles

29

Brown, Carol A. "Biomass production, composition, and ethanol potential of switchgrass grown on reclaimed surface mines in West Virginia." Thesis, West Virginia University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1573301.

Full text

Abstract:

Growing crops for biofuel production on agricultural land has caused a debate between whether we should grow corn grain on productive, agricultural lands to feed a growing human population or to fuel our vehicles. This has increased interest in growing cellulosic biofuel feedstocks on marginal lands. Switchgrass (Panicum virgatum L.), a warm-season perennial grass, has been shown to be a viable bioenergy crop because it produces high yields on marginal lands under low water and nutrient conditions. West Virginia contains immense acreages of reclaimed surface mine lands and could offer enough area for the production of switchgrass as a feedstock for a biofuel industry.

The first study was established in 2008 to determine switchgrass yields of three different cultivars on two mine sites in West Virginia. The first site, which was reclaimed in the early 1990s using top soil and treated municipal sludge, consistently had the highest yield of the two sites with a sixth-year yield of 8.4 Mg Dry Matter (DM) ha^-1 averaged across varieties. Cave-in-Rock variety produced 13.0 Mg ha^-1 of biomass which was more than the other two varieties. The other site, Hobet, was prepared using crushed, unweathered sandstone in 2008 and average yields were 1.0 Mg ha^-1 for the sixth year of production.

The second study was conducted on two sites which were reclaimed with a layer of topsoil over gray overburden and seeded with Cave-in-Rock 2011. Fertilizer was applied at rates of 0, 33.6, and 67 kg N ha^-1. No fertilizer treatment yielded 0.32 Mg ha^-1 while the fertilizer treatments produced significantly higher yields.

The objective of the third study was to determine if cultivars and samples from fertilizer treatments differed in composition and theoretical ethanol yield. Compositional analysis was done using near infrared reflectance spectroscopy. It was determined that cultivars did not differ in theoretical ethanol yield with averages ranging from 364 to 438 L Mg^-1. Theoretical ethanol production from Cave-in-Rock was significantly higher ranging from 6,092 to 7,348 L ha^-1 due to its high biomass production. Fertilizer treatments did not greatly effect composition of switchgrass, but since it did improve yield this was reflected in greater ethanol production for fertilized treatments. Based on the information presented here, high biomass should be the goal for switchgrass grown for biofuel production. With proper soil substrate and fertilizer regime, switchgrass grown on reclaimed surface mines may have high enough yield and quality to support ethanol production in the future.

APA, Harvard, Vancouver, ISO, and other styles

30

Ali, Wael. "Modelling of Biomass Production Potential of Poplar in Short Rotation Plantations on Agricultural Lands of Saxony, Germany." Doctoral thesis, Technische Universität Dresden, 2008. https://tud.qucosa.de/id/qucosa%3A23743.

Full text

Abstract:

The interest in renewables for energy has increased in the last 2-3 decades because of the negative environmental impact caused by the burning of fossil fuels, the raising prices of traditional fuels, the dependence on foreign oil, and the decrease in fossil fuels resources. Biomass energy represents one of the most promising alternatives. Many studies worldwide were devoted to investigate growth and yield of short rotation forestry plantations for energetic use and several empirical and process-based models were developed to predict the potential production of biomass. The current work was concentrated on modelling site productivity (potential of biomass production) of specific poplar clones planted on arable Saxon land under different stocking densities. Empirical data collected from several experimental areas were used. Site productivity has been predicted depending on stand age and site variables using a two-step model. In step one age and site variables were used to model stand dominant height and in step two the constructed dominant height was involved with stocking density to predict stand oven dried biomass. Depending on data availability the model was parameterized for four different groups of poplar clones: Androscoggin (clone Androscoggin), Matrix (Matrix and hybrid 275), Max (Max 1 …Max 5) and Münden (clone Münden). Both stand dominant height and stand dry biomass were modelled for ages 2 – 9 years for clone groups: Matrix and Max and for ages 2 – 7 years for clone groups: Androscoggin and Münden. The model has been tested and validated using several statistical and graphical methods. The relative bias (ē %) in the dominant height estimates ranged between 0.5 % > ē % > - 0.5 % in all clone groups and had a maximum bias of 10.41 % in stand biomass estimates. Model accuracy (mx %) in the dominant height estimates ranged between 12.25 and 17.56 % and between 8.05 and 27.32 % in stand biomass estimates. Two different scenarios were presented to show the potential of biomass that can be produced from poplar plantations on arable and former fallow Saxon lands at different stocking densities. ArcGIS has been used to visualize model application results. In order to produce a mean annual increment ≥ 8 [dry t/ha/a] from poplar plantations (Max group) for more than 50 % of arable or former fallow lands in the first rotation at least 9 years are required under stocking density of 4000 stems/ha and 7 years for both stocking densities 8333 and 10,000 stems/ha.
Die Nachfrage nach Holz für energetische Zwecke nimmt in Deutschland und ganz Europa zu. Um diesen Bedarf künftig besser befriedigen zu können, müssen verstärkt Ressourcen aus verschiedenen Quellen wie z. B. Holz aus Niederwäldern oder Durchforstungsreserven im Hochwald mobilisiert und ergänzend Holz in Kurzumtriebsflächen produziert werden (Guericke, M. 2006). Ziel dieser Arbeit war es, das Ertragspotential von Pappelklonen in Kurzumtriebsplantagen unterschiedlicher Baumdichte auf sächsischen Ackerflächen zu untersuchen. Hierzu wurden die potentiellen Erträge anhand empirischer, auf verschiedenen Versuchsflächen erhobener Daten modelliert. Zur Schätzung des Ertragspotentials wurde ein zweistufiges Modell entwickelt: Im ersten Schritt erfolgte die Modellierung der Oberhöhe eines Bestandes (ho, m) in Abhängigkeit von Bestandesalter und Standortfaktoren unter Verwendung einer multiplen linearen Regressionsanalyse, dabei wurden Bestimmtheitsmaße (R²) von 0,975 bis 0,989 erreicht. In einem zweiten Schritt lässt sich dann der Biomassevorrat [tatro/ha/a] mittels nichtlinearer Regressionsanalyse durch die Bestandesoberhöhe schätzen. Das Bestimmtheitsmaß von R² ≥ 0,933 weist auch hier auf eine hohe Anpassungsgüte hin. Die Modellparametrisierung erfolgte für folgende vier Gruppen von Pappelklonen: • Max-Gruppe: Klone Max 1, Max 2, Max 3, Max 4 und Max 5, Altersbereich 2 – 9 Jahre, Baumdichten von 1150 – 13000 Stämmen/ha; • Matrix-Gruppe: Klon Matrix und Hybride 275, Altersbereich 2 – 9 Jahre, Baumdichte 1550 Stämme/ha; • Androscoggin-Gruppe: Klon Androscoggin, Altersbereich 2 – 7 Jahre, Baumdichte 1550 Stämme/ha; und • Münden-Gruppe: Klon Münden, Altersbereich 2 – 7 Jahre, Baumdichte 1550 Stämme/ha. Die Güte des Modells wurde mit Hilfe verschiedener statistischer Verfahren überprüft. Bei der Validierung anhand des Datensatzes, welcher für die Modellkonstruktion Verwendung fand, zeigte das Modell eine Verzerrung bzw. einen Bias von 0,5 % > ē % > - 0,5 % bei der Bestandesoberhöhenschätzung und einen maximalen Bias von 10,41 % bei der Schätzung der Bestandesbiomasse. Die Treffgenauigkeit (mx %) des Modells hingegen variierte zwischen 12,25 % und 17,56 % bzw. 8,05 und 27,32 % (bei Schätzung der Bestandesoberhöhe bzw. der Bestandesbiomasse). Zudem wies das Modell keinen systematischen Fehler zwischen den geschätzten und den realen Werten auf. Bei der Validierung mit einem unabhängigen Datensatz betrug die Treffgenauigkeit (mx %) für die Schätzung der Bestandsoberhöhe und des Biomassevorrates 15,72 bzw. 26,68 %. Um das Ertragspotenzial von Pappelplantagen für die gesamte sächsische Ackerfläche bzw. die gesamte ehemalige Stilllegungsfläche zu bestimmen, wurden die zu Schätzung erforderlichen Standortvariablen auf Gemeindebasis kalkuliert, mittels ArcGIS dargestellt sowie Simulationsrechungen für verschiedene Bestandsdichten vorgenommen und ebenfalls visualisiert. Den Ergebnissen der Simulationsrechnungen zufolge wäre bei einer Stammzahl von 4000 N/ha eine Rotationslänge von 9 Jahren, bei 8333 bis 10.000 N/ha von 7 Jahren erforderlich, um einen durchschnittlichen Gesamtzuwachs (dGz) von ≥ 8 [tatro/ha/a] auf mehr als 50 % der sächsischen Ackerflächen bzw. ehemaligen Stilllegungsflächen in erster Rotation zu erreichen. Würde die gesamte ehemalige sächsische Stilllegungsfläche mit einer Baumdichte von 10.000 Stämmen/ha bepflanzt werden, könnten Pappelplantagen im Alter 9 einen dGz von 520.000 [tatro/a] (entsprechend 250.000 Kubikmeter Diesel) erreichen. Bei Bestockung aller sächsischen Ackerflächen würde sich der Ertrag auf bis zu 9.087.000 [tatro/a] (entsprechend 4.367.000 Kubikmeter Diesel) erhöhen.

APA, Harvard, Vancouver, ISO, and other styles

31

Marchello, Adriano Evandir. "Mixotrophy in Chlorella sorokiniana : physiology, biotechnological potential and ecotoxicology." Universidade Federal de São Carlos, 2017. https://repositorio.ufscar.br/handle/ufscar/8936.

Full text

Abstract:

Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2017-08-08T16:54:32Z No. of bitstreams: 1 TeseAEM.pdf: 3699711 bytes, checksum: 3b2fdf705faaa9314eeacec123aa76fd (MD5)
Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-08T17:28:23Z (GMT) No. of bitstreams: 1 TeseAEM.pdf: 3699711 bytes, checksum: 3b2fdf705faaa9314eeacec123aa76fd (MD5)
Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-08T17:28:30Z (GMT) No. of bitstreams: 1 TeseAEM.pdf: 3699711 bytes, checksum: 3b2fdf705faaa9314eeacec123aa76fd (MD5)
Made available in DSpace on 2017-08-08T17:38:21Z (GMT). No. of bitstreams: 1 TeseAEM.pdf: 3699711 bytes, checksum: 3b2fdf705faaa9314eeacec123aa76fd (MD5) Previous issue date: 2017-06-09
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
In aquatic environments, phytoplankton consists mostly of photosynthetic microorganisms that serve as the basis of food chains. However, besides photoautotrophy, it is widely reported in the literature that many microalgae can take up dissolved organic matter present in the environment concomitantly with the photosynthesis, a metabolic pathway known as mixotrophy. Little is known about the ecophysiology of mixotrophy in microalgae, and almost all studies are focused on the use of this metabolic pathway to increase the production of algal biomass and stimulate the production of specific biomolecules. Another important issue, considering the current anthropic activity, is that most of the contaminants eliminated in aquatic environments, such as metals and nanoparticles, affect the phytoplankton. However, so far, no ecotoxicological study involving mixotrophic metabolism was found in the literature. To better understand mixotrophy in microalgae, this work chose the chlorophycean freshwater Chlorella sorokiniana as test organism. We divided the study into two parts: the first focused on the physiological/biotechnological interest through the study of growth, photosynthetic parameters, changes in cellular volume, and production of biomolecules (proteins, carbohydrates and lipids); the second part focused on the ecotoxicological effects of cadmium (Cd) and titanium dioxide nanoparticles (NPs-TiO2). To stimulate mixotrophy, glucose (1.0 g.L-1 or 5 x 10-3 mol.L-1) was used as the organic carbon source. The results showed that during mixotrophy, the microalga C. sorokiniana presented higher population growth and production of biomolecules, such as chlorophyll a and lipids, when compared to photoautotrophic cultures. It was also observed that the photosynthetic parameters were affected by mixotrophy, although they did not interfere in the growth of the microalga, and that the presence of bacteria in the cultures acted as a stimulant factor in the production of algal biomass. Regarding the ecotoxicological effects of contaminants, microalgae in mixotrophy were more resistant to both Cd and NPs-TiO2 than those in photoautotrophy, but with changes in the biochemical composition what can affected the energy transfer in the environment. In general, we can conclude that mixotrophy should be considered in studies with phytoplankton, since aquatic environments present a myriad of organic carbon that can be used by these microorganisms. As general conclusions, we can mention that organic carbon acted as an extra source of structural carbon and energy for microalgae, not necessarily relying solely on photosynthesis to survive, so stimulating the growth and production of biomolecules of biotechnological interest, and increased cellular viability in environments contaminated with metals and nanoparticles. This study is a contribution to the understanding of mixotrophy and photoautotrophy metabolisms in a freshwater Chlorophyta with biotechnological potential.
Nos ambientes aquáticos, o fitoplâncton é formado basicamente de microrganismos fotossintetizantes que servem como base das cadeias alimentares. Entretanto, além da fotoautotrofia, é vastamente citado na literatura que muitas microalgas alimentam-se de matéria orgânica dissolvida presente no ambiente concomitantemente à realização da fotossíntese, uma via metabólica conhecida como mixotrofia. Sabe-se pouco sobre a ecofisiologia em metabolismo mixotrófico nas microalgas, sendo os estudos, em sua quase totalidade, voltados ao uso dessa via metabólica para aumentar a produção de biomassa algal e estimular a produção de biomoléculas específicas. Outra questão importante, considerando a atividade antrópica atual, é que a maioria dos contaminantes eliminados nos ambientes aquáticos, como metais e nanopartículas, são estudados em fitoplâncton sob metabolismo fotoautotrófico, não sendo encontrados trabalhos ecotoxicológicos envolvendo o metabolismo mixotrófico na literatura. Para entender melhor o metabolismo algal em mixotrofia, este trabalho escolheu a microalga Chlorophyta de água doce Chlorella sorokiniana como organismo-teste. Para melhor organizá-lo, foi dividido em duas partes: a primeira focou no interesse fisiológico/biotecnológico através do estudo do crescimento, parâmetros fotossintéticos, volume celular, e produção de biomoléculas (proteínas, carboidratos e lipídeos); a segunda parte focou nos efeitos ecotoxicológicos de cádmio (Cd) e de nanopartículas de dióxido de titânio (NPs-TiO2). Para estimular a mixotrofia, glicose (1.0 g.L-1 ou 5 x 10-3 mol.L-1) foi utilizada como fonte de carbono orgânico. Os resultados mostraram que durante a mixotrofia, a microalga C. sorokiniana apresentou maiores crescimento populacional e produção de biomoléculas, como clorofila a e lipídeos, quando comparada com as culturas em fotoautotrofia. Também foi observado que os parâmetros fotossintéticos foram afetados em mixotrofia, porém não interferindo no crescimento da microalga, e que a presença de bactérias pode ter atuado como fator estimulante na produção de biomassa algal. Em relação aos efeitos ecotoxicológicos dos contaminantes, as microalgas em mixotrofia foram mais resistentes tanto ao Cd quanto às NPs-TiO2 do que em fotoautotrofia, porém com mudanças na composição bioquímica, podendo afetar a transferência de energia nos ecossistemas aquáticos. De modo geral, podemos concluir que a mixotrofia deve ser considerada em estudos com fitoplâncton, visto que os ambientes aquáticos apresentam uma miríade de fontes de carbono orgânico para esses microrganismos. Na mixotrofia, o carbono orgânico funciona como uma fonte extra de carbono estrutural e de energia para as microalgas, não dependendo obrigatoriamente somente da fotossíntese para sobreviver, estimulando o crescimento e produção de biomoléculas de interesse biotecnológico, além de aumentar a viabilidade celular em ambientes contaminados tanto com Cd quanto com NPs-TiO2. Este estudo é uma contribuição ao entendimento dos metabolismos mixotróficos e fotoautotróficos em uma Chlorophyta de água doce com potencial biotecnológico.
CNPq: 302175/2015-6
FAPESP: 2014/15894-0

APA, Harvard, Vancouver, ISO, and other styles

32

Norell, Isabella. "Phaeodactylum tricornutum – Compositional Analysis, Carbohydrate-Active Enzymes and Potential Applications of Residual Algal Biomass from Omega 3 Production." Thesis, KTH, Industriell bioteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292409.

Full text

Abstract:

Microalgae are gaining more attention for several reasons such as being potential producers of sustainable fuel, for use as health supplements and in skincare. Simris Alg is a Swedish company that produces Omega 3 supplements from a primary producer of these fatty acids - the algal diatom Phaeodactylum tricornutum, which is a sustainable alternative to Omega 3 derived from fish. Omega 3 fatty acids constitute a small fraction of the total algal biomass, and to increase profitability and utilize all of the biomass, the purpose of this thesis project is to present potential applications for the residual material that is left after oil extraction. A general composition study was made of Simris Alg algal residue material, and results are compared to those found in previous studies of P. tricornutum biomass. An optimization of the fractionation is needed to separate the storage carbohydrate chrysolaminarin and cell wall component glucuronomannan, followed by analysis for confirmation. Also, it would be interesting to separate chitin, if there is any, since despite the presence of chitin synthases, it is unclear whether the diatom actually produces chitin. When gathering information, no actual experimental characterization of carbohydrate active enzymes involved in synthesis of the main carbohydrates investigated were found. Such information would be useful to increase production of the carbohydrate of interest, if valuable applications are found. Potential applications of various cell components, such as carbohydrates, in skincare would be interesting to investigate, as well as optimizing fucoxanthin extraction for use as an additional high value product next to Omega 3.

APA, Harvard, Vancouver, ISO, and other styles

33

Botman, Ilse. "Production potential of Eucalypt woodlots for bioenergy in the Winelands region of the Western Cape." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4281.

Full text

Abstract:

Thesis (MScFor (Forest and Wood Science))--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: The purpose of the study was to investigate the potential tree taxa that could be grown as a source of biomass in the Cape Winelands region. The trials comprises of two different aspects. The first being the estimation of potential volume, density and biomass of a pair of six year-old stands of E. gomphocephala and E. cladocalyx families at two climatically different sites within the study region. The second part of the study was the early growth assessment of alternative taxa that could be planted in the region compared to the regional mainstay E. cladocalyx. The volume of families was estimated using appropriate volume equations and using the form height were none were available. The best volume yield varied from 4.6 to 11.2 m3 ha-1a-1, at the dry and sub-humid sites, respectively. Wood density, estimated from non-destructive samples at both sites, varied from 620 (sub-humid) to 588 kg m-3 (dry site). The estimated biomass production rate of the top producing families yielded 2.7 and 6.9 t ha -1a -1 at the dry and sub-humid sites, respectively. In terms of estimated biomass and survival, E. gomphocephala was more suited to the dry site, while E. cladocalyx displayed superior yield than E. gomphocephala on the sub-humid site, but not significantly so. Early growth assessment of the trial of alternative taxa found that the hybrid E. grandis × camldulensis and E. grandis × urophylla had superior biomass indices, but were more susceptible to infestation by Thaumastocoris peregrinus and Gonipterus scuttelatus.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om potensiële boom taksa vir gebruik as ’n bron van biomassa in die Kaapse Wynlandstreek te ondersoek. Die proewe behels twee aspekte: eerstens die beraming van die potensiële volume, digtheid en biomassa van sesjaaroue opstande met families van E. gomphocephala en E. cladocalyx by twee klimatologies verskillende groeiplekke in die studiegebied; tweedens die beoordeling van die vroeë groei van alternatiewe taksa wat in die streek geplant kan word in vergelyking met die streek se historiese staatmaker-spesie E. cladocalyx. Die volume van die families is beraam deur gebruik te maak van toepaslike volumevergelykings, en met behulp van ’n vormfaktor waar vergelykings nie beskikbaar was nie. Die volume aanwas by die droë en sub-humiede groeiplekke was onderskeidelik 4.6 en 11.2 m3 ha-1j-1. Houtdigtheid is beraam deur nie-destruktiewe monsters uit die opstand te neem. Gemiddelde digthede het variëer van 588 (sub-humied) tot 620 kg m-3 (droë groeiplek). Die beraamde biomassaproduksie van die top-families beloop onderskeidelik 2.7 en 6.9 t ha -1j -1 vir die droë en sub-humiede groeiplekke. In terme van beraamde biomassa en oorlewing, is E. gomphocephala meer geskik vir droër groeiplekke , terwyl E. cladocalyx by die sub-humiede groeiplek ’n hoër opbrengs as E. gomphocephala getoon het, hoewel nie betekenisvol nie. Beramings van die vroeë groei by die proef met alternatiewe taksa het getoon dat die basters E. grandis × camldulensis en E. grandis × urophylla hoër biomassa-indekse het, maar meer vatbaar is vir besmetting deur Thaumastocoris peregrinus en Gonipterus scuttelatus.
Centre for Renewable and Sustainable Energy Studies

APA, Harvard, Vancouver, ISO, and other styles

34

Eriksson, Anna-Maria. "Torrefaction and gasification of biomass. The potential of torrefaction combined with entrained-flow gasification for production of synthesis gas." Thesis, KTH, Skolan för kemivetenskap (CHE), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-146313.

Full text

Abstract:

Torrefaction of biomass together with gasification in entrained-flow reactors is a new possible way of producing synthesis gas. The synthesis gas can later be used for the production of renewable liquid fuels. This is highly desirable since the transport sector consumes a high amount of fossil fuels that has to be exchanged for renewable fuels in the future. It is hard to tell if the technology above is an advantageous way or not to produce synthesis gas since it is very newly developed. A lot of obstacles exist such as the injection of the torrefied wood into the gasifier, the optimization of the ash flow down the entrained flow reactor and the high energy consumption of the drying. Investigation in the form of material and energy balances shows that the system can have as high energy efficiency as 73% and cold gas efficiency of 74% which is only slightly less then what the fluid-bed gasification has. Torrefaction and gasification developers allocate huge amount of money to develop torrefaction and entrained-flow gasification units. Interviews show that many experts believe that the technology will be commercial and used to produce renewable liquid fuels in the future.

APA, Harvard, Vancouver, ISO, and other styles

35

Du, Bowen Chambliss C. Kevin. "Effect of varying feedstock-pretreatment chemistry combinations on the production of potentially inhibitory degradation products in biomass hydrolysates." Waco, Tex. : Baylor University, 2009. http://hdl.handle.net/2104/5319.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Pittman, Kara. "High Residue Cover Crops for Annual Weed Suppression in Corn and Soybean Production and Potential for Hairy Vetch (Vicia villosa) to be Weedy." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/82041.

Full text

Abstract:

After termination, cover crop residue can suppress weeds by reducing sunlight, decreasing soil temperature, and providing a physical barrier. Experiments were implemented to monitor horseweed suppression from different cover crops as well as two fall-applied residual herbicide treatments. Results suggest that cover crops, other than forage radish in monoculture, can suppress horseweed more consistently than flumioxazin + paraquat or metribuzin + chlorimuron-ethyl. Cover crop biomass is positively correlated to weed suppression. Subsequent experiments were designed to determine the amount of weed suppression from different cover crop treatments and if carbon to nitrogen (C:N) ratios or lignin content are also correlated to weed suppression or cover crop residue thickness. Results indicate that cereal rye alone and mixtures containing cereal rye produced the most biomass and suppressed weeds more than hairy vetch, crimson clover, and forage radish alone. Analyses indicate that lignin, as well as biomass, is an important indicator of weed suppression. While cover crops provide many benefits, integrating cover crops into production can be difficult. Hairy vetch, a legume cover crop, can become a weed in subsequent seasons. Multiple experiments were implemented to determine germination phenology and viability of two hairy vetch cultivars, Groff and Purple Bounty, and to determine when viable seed are produced. Almost all germination occurred in the initial cover crop growing season for both cultivars. Both cultivars had <1% of viable seed at the termination of the experiment. These results indicate that seed dormancy is not the primary cause of weediness.
Master of Science in Life Sciences

APA, Harvard, Vancouver, ISO, and other styles

37

Pittman, Kara Brooke. "High Residue Cover Crops for Annual Weed Suppression in Corn and Soybean Production and Potential for Hairy Vetch (Vicia villosa) to be Weedy." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/82041.

Full text

Abstract:

After termination, cover crop residue can suppress weeds by reducing sunlight, decreasing soil temperature, and providing a physical barrier. Experiments were implemented to monitor horseweed suppression from different cover crops as well as two fall-applied residual herbicide treatments. Results suggest that cover crops, other than forage radish in monoculture, can suppress horseweed more consistently than flumioxazin + paraquat or metribuzin + chlorimuron-ethyl. Cover crop biomass is positively correlated to weed suppression. Subsequent experiments were designed to determine the amount of weed suppression from different cover crop treatments and if carbon to nitrogen (C:N) ratios or lignin content are also correlated to weed suppression or cover crop residue thickness. Results indicate that cereal rye alone and mixtures containing cereal rye produced the most biomass and suppressed weeds more than hairy vetch, crimson clover, and forage radish alone. Analyses indicate that lignin, as well as biomass, is an important indicator of weed suppression. While cover crops provide many benefits, integrating cover crops into production can be difficult. Hairy vetch, a legume cover crop, can become a weed in subsequent seasons. Multiple experiments were implemented to determine germination phenology and viability of two hairy vetch cultivars, Groff and Purple Bounty, and to determine when viable seed are produced. Almost all germination occurred in the initial cover crop growing season for both cultivars. Both cultivars had <1% of viable seed at the termination of the experiment. These results indicate that seed dormancy is not the primary cause of weediness.
Master of Science in Life Sciences

APA, Harvard, Vancouver, ISO, and other styles

38

Reyes, Sánchez Nadir. "Moringa oleifera and Cratylia argentea : potential fodder species for ruminants in Nicaragua /." Uppsala : Dept. of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200601.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Suopajärvi, H. (Hannu). "Bioreducer use in blast furnace ironmaking in Finland:techno-economic assessment and CO₂ emission reduction potential." Doctoral thesis, Oulun yliopisto, 2015. http://urn.fi/urn:isbn:9789526207063.

Full text

Abstract:

Abstract Most of the steel produced in the world is based on the integrated blast furnace-converter route, which is based on the use of virgin raw materials. Large amounts of fossil-based, carbon containing reductants are used in blast furnaces, which results in carbon dioxide emissions into the atmosphere. Fossil carbon dioxide emissions from steel production can be reduced by new technologies or moving from non-renewable to renewable energy sources. Biomass-based reductants could be one way to reduce the specific emissions from blast furnace-based steel production. The aim of this thesis was to examine the techno-economic and CO₂ mitigation potentials of using bioreducers in blast furnace ironmaking. Bioreducer feasibility was analyzed in the Finnish context, but the research methods used can be applied more widely. The metallurgical properties of bioreducers were evaluated and compared to fossil-based reductants. The impact of bioreducers on blast furnace behavior and on other steel plant processes was evaluated, with an emphasis on the reductions achieved in CO₂ emissions at the plant scale. The CO₂ emissions, energy consumption and production costs of bioreducers were evaluated, as was the availability of energy wood for bioreducer production. The results show that solid, liquid and gaseous bioreducers can be produced with thermochemical conversion technologies. However, their suitability for blast furnace use varies greatly. The highest substitution of fossil-based reductants in a blast furnace is achieved with charcoal injection. The carbon footprint of torrefied wood, charcoal and Bio-SNG is moderate compared to fossil-based reducing agents and their production is energetically feasible. The economic feasibility of bioreducers is currently weak in comparison to fossil-based reducing agents, but competitive when compared to other CO₂ emission reduction measures such as carbon capture and storage. The biomass availability assessment revealed that sufficient amount of energy wood could be available for bioreducer production in the areas where Finnish steel plants are situated. The feasibility of bioreducer production could be improved by producing a number of products from the biomass and taking advantage of the process of integration possibilities
Tiivistelmä Suurin osa maailmassa tuotetusta teräksestä valmistetaan integroidulla masuuni-konvertteri reitillä, joka perustuu neitseellisten raaka-aineiden käyttöön. Masuuniprosessissa käytetään suuri määrä fossiilisia, lähinnä hiilipohjaisia pelkistimiä, jotka aiheuttavat hiilidioksidipäästöjä ilmakehään. Fossiilisia hiilidioksidipäästöjä voidaan teräksenvalmistuksessa vähentää uusilla teknologioilla tai siirtymällä uusiutumattomista energialähteistä uusiutuviin. Biomassasta valmistetut pelkistimet voisivat olla yksi mahdollinen keino alentaa masuunipohjaisen teräksenvalmistuksen ominaispäästöjä. Tämän työn tavoitteena oli tarkastella biopelkistimien käytön teknistaloudellista potentiaalia masuunikäytössä ja aikaansaatavia hiilidioksidipäästövähenemiä eri systeemirajauksilla. Työssä keskityttiin tarkastelemaan biopelkistimien hyödynnettävyyttä lähinnä Suomen tasolla, vaikka käytetyt tutkimusmetodit ovat sovellettavissa myös laajemmin. Työssä arvioitiin biopelkistimien metallurgisia ominaisuuksia, niiden vaikutusta masuuniprosessiin ja laajemmin muihin terästehtaan prosesseihin, pääpainon ollessa saavutettavan CO₂ päästövähenemän tarkastelussa. Työssä tarkasteltiin biopelkistimien valmistuksen CO₂ päästöjä, energiankulutusta ja tuotantokustannuksia sekä energiapuun saatavuutta biopelkistimien tuotantoon. Tulokset osoittavat, että biomassasta voidaan valmistaa kiinteitä, nestemäisiä ja kaasumaisia pelkistimiä termokemiallisilla konversioteknologioilla, joiden soveltuvuus masuunikäyttöön vaihtelee suuresti. Masuuniprosessissa suurin fossiilisten pelkistimien korvaavuus saavutetaan käyttämällä puuhiili-injektiota. Torrefioidun puun, puuhiilen ja Bio-SNG:n hiilijalanjälki on varsin maltillinen verrattuna fossiilisiin pelkistimiin ja niiden tuotanto on energeettisesti järkevää. Biopelkistimien taloudellinen kannattavuus verrattuna fossiilisiin pelkistimiin on tällä hetkellä heikko, mutta kilpailukykyinen verrattuna muihin CO₂ päästöjen vähennyskeinoihin, kuten hiilidioksidin talteenottoon ja -varastointiin. Energiapuun saatavuus biopelkistimien valmistukseen on suurin alueilla, jotka sijaitsevat lähellä Suomen terästehtaita. Biopelkistimien tuotannon kannattavuutta voitaisiin parantaa tuottamalla useita tuotteita ja hyödyntämällä prosessi-integraatiota

APA, Harvard, Vancouver, ISO, and other styles

40

Lebon, Édouard. "Optimisation de la méthanisation sèche des déchets ménagers." Thesis, La Réunion, 2019. http://elgebar.univ-reunion.fr/login?url=http://thesesenligne.univ.run/19_43_ELebon.pdf.

Full text

Abstract:

Face aux problématiques de gestion des déchets à La Réunion, il est urgent de définir des solutions efficaces et cohérentes, tout en respectant un environnement insulaire, dont les ressources en sols et eau sont fortement sollicitées. L'une des solutions pour la gestion des déchets organiques d'origine humaine ou animale est la digestion anaérobie aussi appelée méthanisation. Les volumes de déchets collectés par les diverses collectivités locales à La Réunion ne cessent globalement d'augmenter. Les centres de stockage et de traitement peinent à suivre cette tendance en raison des contraintes foncières et réglementaires. Sur le territoire de la Réunion, le volume d'ordures ménagères est de 313 kg/habitant/an. Or, la fraction organique des ordures ménagères (FFOM) collectées dispose d'un potentiel important en méthanisation qu'il convient d'examiner de manière précise afin de déterminer les conditions de valorisation par production de biogaz. Le travail de thèse proposé ici a pour objectif d'étudier de façon scientifique et technique le potentiel de développement de la méthanisation de la FFOM à La Réunion par la technique de méthanisation sèche. Pour se faire, un premier travail de caractérisation des déchets ménagers a été mené sur le territoire de la Réunion. Puis, le potentiel méthane de la FFOM a été déterminé expérimentalement suivant un plan de mélange permettant de mettre en évidence l’effet synergique des différents déchets composant la FFOM. En parallèle, un modèle cinétique de production de méthane, un modèle prédictif ainsi qu’une modification de modèle ADM1 ont été développés
It is urgent to define effective and coherent solutions to the problems of waste management in Reunion Island, while respecting the island's environment, whose soil and water resources are under great strain. One solution for organic waste management of human or animal origin is anaerobic digestion (AD). Overall, the volumes of waste collected by the various local authorities on Reunion Island are constantly increasing. Storage and treatment centres are struggling to keep up with this trend due to land and regulatory constraints. On Reunion Island, the volume of household waste is 313 kg/inhabitant/year. However, the organic fraction of municipal solid waste (OFMSW) collected has a significant potential for AD that needs to be examined in detail in order to determine the conditions for recovery by biogas production. The aim of this work is to study in scientifically and technically the potential development of the dry AD of OFMSW in Reunion Island. For this purpose, a first work of characterisation of household waste has been carried out on the territory of Reunion Island. Next, the methane potential of the OFMSW was determined experimentally following a mixing plan to highlight the synergistic effect of the different types of OFMSW. In addition, a kinetic model for methane production, a predictive model and a modification of the ADM1 model were developed

APA, Harvard, Vancouver, ISO, and other styles

41

Mabhegedhe, Munamato. "Analysis of euoniticellus intermedius, larva gut micro-flora: potential application in the production of biofuels." Thesis, 2012. http://hdl.handle.net/10539/11936.

Full text

Abstract:

Recent years have seen a dramatic increase in first generation bio-fuel production, mainly driven by concerns of climate change and rising prices of transportation fossil fuels. Due to significant pressure on the few available food sources, second generation bio-fuels have entered the fray, as a sustainable alternative. This research‟s aim was to search for cellulolytic micro-organisms and enzymes from the gut of the dung beetle, Euoniticellus intermedius, (Coleoptera: Scarabaeida) that can be used in the production of second generation bio-fuels. Dung beetle larvae were dissected and the gut micro-flora cultured in cellulose medium. Bacterial growth and cellulase activity was monitored on a daily basis. DNA isolation was then done on the cellulose medium-cultured microbes and the isolated DNA cloned in E. coli. The clones were screened for cellulase activity using plate assays. A total of 7 colonies out of 160 screened colonies showed positive CMC (endo-β-1,4-glucanase) and MUC (cellobiohydrolase) activities. Sequencing of these positive colonies yielded mostly bacteria belonging to the Enterobacteriaceae family, most of which have not been previously reported to have cellulase activity. This study‟s findings prove that in addition to this dung beetle‟s gut being a fruitful source of microbial biodiversity, it is also a potential source of cellulolytic micro-organisms and enzyme activities that will aid the function and design of future bioreactors for the bio-fuel industry.

APA, Harvard, Vancouver, ISO, and other styles

42

Smith, Maria. "A multiple scenario analysis into the potential for bioethanol production from maize in South Africa." Thesis, 2010. http://hdl.handle.net/10210/3280.

Full text

Abstract:

M.Sc.
Biofuels have the potential to reduce a country’s dependence on imported oil, to ensure diversity of energy sources, to increase the availability of renewable energy sources and to address global environmental issues. In recognition of the potential benefits of the production and use of biofuels, the Department of Minerals and Energy released the Draft Biofuels Industrial Strategy in December 2006 with the aim to increase the use of biofuels in South Africa to replace 4.5% of conventional transport fuels by 2013. However, there are several barriers that need to be overcome before South Africa can establish a large-scale biofuel industry to achieve the DME’s biofuel target. This includes environmental barriers, such as the availability of land for the cultivation of biofuel feedstocks and potential threats to food security. This study focuses on these environmental barriers and aims to determine the potential for bioethanol production from maize in South Africa to 2013. To this purpose, a bioethanol potential model is developed to simulate the potential for bioethanol production from maize in South Africa between 2008 and 2013. The model incorporates four key elements that all impact on the availability of maize for bioethanol production, namely: maize demand; maize supply; the demand for maize as biomaterial; and the available land area for the cultivation of maize. The study makes further use of the scenario planning method to determine the potential for bioethanol production from maize in South Africa. Four unique bioethanol potential scenarios are designed and simulated within the bioethanol potential model developed for this purpose. Each scenario plays out a differentstoryline for the future social, economic and natural environment that will impact on the availability of maize for bioethanol production. The results of the bioethanol potential scenario simulations show that South Africa will be able to produce enough maize to meet the DME’s biofuel target of 1.2 billion liters of bioethanol for all scenarios between 2009 and 2010. From 2011 onwards, the bioethanol potential decreases below the DME’s target value in both the worst case and rapid change scenarios. The study concludes that the production of bioethanol from maize in South Africa will have various social, economic and environmental consequences for the country’s agricultural sector. The depletion of domestic maize supplies will seriously threaten food security and consequently, increase the country’s dependence on maize imports. This will not only affect the country’s maize producing regions, but spread throughout South Africa as the demand for agriculturally productive land for maize production increases. Domestic food security is therefore at risk and South Africa will have to resort to other energy technologies to achieve a sustainable and renewable energy future for road transport.

APA, Harvard, Vancouver, ISO, and other styles

43

Chih-MingSu and 蘇峙銘. "Effects of light and nutrient availability on the biomass production, CO2 fixation, and bioethanol production potential of Thermosynechococcus sp. in flat plate photo−bioreactors." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/axf627.

Full text

Abstract:

博士
國立成功大學
環境工程學系
107
The concept of CO2 chemo−absorption by sodium hydroxide in a wet scrubber followed by microalgae cultivation was used potentially as a means to reduce the major greenhouse gas, CO2. This study accepted the idea by utilized dissolved inorganic carbon as carbon source to cultivate thermophilic cyanobacteria strain, Thermosynechococucs CL−1 (TCL−1), and designed flat plate photobioreactors for cultivating this strain without excess energy input for cooling the flat plate photobioreactor as other researchers did. In order to apply TCL−1 in biomass production, CO2 fixation, and bioenergy production, and more close to reality of cultivation the strain outdoors, light emitting diodes array were used as the light source with strong illumination. Effects of aeration rates, illumination intensities, and biomass concentrations were examined in advance under designed light path to evaluate how light availability affects TCL−1. Results suggest that most of these parameters play major roles in biomass production, CO2 fixation, and carbohydrate production. However, aeration rate of 0.5 vvm is adequate because no significant improvement of biomass production can be observed under greater aeration rates. In addition, the biomass productivity, CO2 fixation rate, and carbohydrate productivity reached 116, 170, and 67 mg L−1 h−1, respectively, in 1.5 cm light path photobioreactor and under optimal biomass concentration of about 3 g biomass L−1. Illumination intensity of 1,000 or 2,000 μE m−2 s−1 had minor effects when under optimal biomass concentration. Moreover, the biomass productivity can’t be increased furthermore when biomass concentration was greater than 3 g L−1. After the investigation of the light availability effects, effects of nutrient availability were also examined under dense culture to test whether the biomass production, CO2 fixation, and bioenergy production potential could be further increased. In addition, glycogen instead of carbohydrate, which may involve other hard fermentable pentose or hexose sugars, were analyzed to have more accurate evaluation of bioethanol production potential. Results show that among all the examined nutrients, concentrations of sodium ion, NaNO3, and CaCl2•2H2O, should be decreased, as the MgSO4•7H2O concentrations should be enhanced to obtain higher biomass productivity or persistence of the growth. Most of the carbon contents in TCL−1 remain stable, about 40% (w/w), under various nutrient levels. In addition, Su and Chu’s medium was reorganized by picking up the nutrient concentrations resulting from the biomass production. The adoption of the new medium for cultivating TCL−1 exhibits the superior biomass productivity, CO2 fixation rate, and glycogen productivity of 138.7, 221.5, and 75.9 mg L−1 h−1, respectively, under 2,000 μE m−2 s−1 illumination in the 1.5 cm light path flat plate photobioreactors. The high biomass productivity, CO2 fixation rate, and glycogen productivity indicate that the use of Su and Chu’s medium exhibits high potential for applying TCL−1 in CO2 fixation and bioethanol production potential in the flat plate photobioreactors.

APA, Harvard, Vancouver, ISO, and other styles

44

Frederick, Kurt R. "Productivity and carbon accumulation potential of transferred biofilms in reclaimed oil sands-affected wetlands." Master's thesis, 2010. http://hdl.handle.net/10048/1667.

Full text

Abstract:

Biofilms are significant contributors to primary production, nutrient cycling, bio-stabilization and the food web of wetland ecosystems. Photoautotrophic biomass (PB) and primary production (PP) were determined for biofilms exposed to various treatments and materials in wetlands near Fort McMurray. Biofilm additions and oil sands process-affected materials were expected to increase the microbial colonization rates on treated substrates and subsequently PB and PP of biofilms over time as compared to controls and unaffected materials. Biofilms survived the transfers and colonized new substrates immediately. Oil sands process affected materials were found to increase PB and PP throughout the first year. A strong decreasing trend for both PB and PP in treatment microcosms occurred in year two, eventually coalescing with control conditions at a lower equilibrium. Transferred biofilms and treatment materials, therefore, increased overall wetland productivity during the initial stages of wetland development when growing conditions are most limiting.
Land Reclamation and Remediation

APA, Harvard, Vancouver, ISO, and other styles

45

Ali, Wael [Verfasser]. "Modelling of biomass production potential of poplar in short rotation plantations on agricultural lands of Saxony, Germany / by Wael Ali." 2009. http://d-nb.info/993933076/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'Biogas production potential'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles