Dissertations / Theses: 'Mechanical and biological treatment of waste'

1

Baptista, Marco Henrique de Carvalho. "Modelling of the kinetics of municipal solid waste composting in full-scale mechanical-biological treatment plants." Doctoral thesis, Faculdade de Ciências e Tecnologia, 2009. http://hdl.handle.net/10362/5908.

Full text

Abstract:

A thesis submitted in fulfilment of the requirements for the Degree of Doctor of Philosophy in Sanitary Engineering in the Faculty of Sciences and Technology of the New University of Lisbon
This work focused on the study of the kinetics of municipal solid waste composting in four full-scale mechanical-biological treatment (MBT) plants. We investigated how well the existent plants in Portugal were being operated, and estimated their performance at optimum operation. To achieve this, volatile solids (VS) content and several environmental conditions, namely temperature (T), moisture content (MC), oxygen concentration ([O2]), and free air space (FAS), were monitored throughout the composting process. Experimental data was fitted with a first-order kinetic model, and a rate constant (k) that corrects for T, MC, [O2] and FAS conditions was obtained, i.e., k is characteristic of composting under optimum environmental conditions. The kinetic model satisfactorily described the experimental data from three MBT plants. k values ranged from 0.043 d-1 to 0.082 d-1. Modelling the fourth plant was less successful,probably due to sampling errors on the VS determinations. This is the first time that a kinetic composting model has been applied to full-scale MBT plants. We also concluded that two of the MBT plants were poorly operated. Optimization of process management with measures of simple practical implementation was estimated to be highly significant in these poorly managed plants, increasing performance by 103% in MBT1 and 53% in MBT2. In conclusion, this work highlights the importance of having process performance monitoring and optimization programs in full-scale composting systems. It is proposed that the procedures developed here are applied for this purpose. The composting model was further tested by applying it to data from lab- and full-scale studies collected from the literature. This is the first time that rate constants from a large set of data sources are corrected for T, MC, [O2] and FAS. k values from full-scale studies varied little, whereas those from lab-scale studies varied widely with k reaching much higher values. These observations indicate that: (i) factors other than those included in the model have a significant effect on the composting rate, as previously suggested; (ii) there is a large margin for improvement in the performance of real-scale systems; (iii) extrapolation of data from laboratory- to full-scale can be misleading and should be cautiously applied; and (iv) more studies of full-scale systems should be conducted, because these constitute an important control over laboratory-scale studies, especially when the aim is the optimization of the design, or operation, of full-scale systems.
European Project “AWAST; 5th Framework Programme (project n. EVK4-2000-00514)

APA, Harvard, Vancouver, ISO, and other styles

2

Velis, C. A. "Solid recovered fuel production through the mechanical-biological treatment of wastes." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/8354.

Full text

Abstract:

This thesis is concerned with the production of solid recovered fuel (SRF) from municipal solid waste using mechanical biological treatment (MBT) plants. It describes the first in-depth analysis of a UK MBT plant and addresses the fundamental research question: are MBT plants and their unit operations optimised to produce high quality SRF in the UK? A critical review of the process science and engineering of MBT provides timely insights into the quality management and standardisation of SRF use in Europe. Quantitative fuel property data for European SRFs are collated and analysed statistically in a detailed examination of the fuel quality achievable from MBT-derived SRF. The experimental research herein applies statistical sampling, analytical characterisation and materials flow analysis to a new generation, fully operational SRF-producing MBT plant. To the author’s knowledge, this is the first detailed analysis of this kind for a UK plant. Individual process flows from mechanically processed waste are characterised using a series of fuel properties in line with the European product standards for SRF, and confidence limits in these properties quantified. New data on SRF quality, including biogenic content, is provided. In seeking understand the variability in waste heterogeneity and its impact on SRF production in an MBT plant, material flow analysis is applied across the MBT flowsheet to compute transfer coefficients for individual unit operations. This provides a basis for critically evaluating the performance of this specific MBT and the extent to which is it optimised for SRF production. Cont/d.

APA, Harvard, Vancouver, ISO, and other styles

3

FERREIRA, ALEXANDRE BANDEIRA DE MELLO. "COMMUNITY MANAGEMENT OF URBAN WASTE AND BIOLOGICAL MECHANIC TREATMENT IN SMALL MUNICIPALITIES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=26693@1.

Full text

Abstract:

Este trabalho apresenta o planejamento e gestão integrados de resíduos sólidos urbanos e tratamento mecânico-biológico, como alternativa para reduzir as Pegadas Ecológicas dos pequenos municípios com a emissão de gases de aterro na disposição de lixo doméstico residual e contribuir para uma política microrregional de sustentabilidade ambiental. O caso estudado é de um grupo de pequenos municípios no sul do estado de Minas Gerais, que, em face da proximidade de seus centros urbanos e interdependência entre suas atividades sociais, econômicas e ambientais, apresentam condições favoráveis aos objetivos do trabalho. Este grupo, constituído pelos municípios de Caxambu, Baependi, Conceição do Rio Verde, Cambuquira, Campanha, Lambari e Jesuânia, encontra-se em uma região de reservas naturais, produção agropecuária, turismo histórico e ecológico prescindindo de políticas públicas, ambientalmente adequadas, para a gestão de resíduos sólidos urbanos. Importa destacar a opção metodológica do trabalho em abordar aspectos das dimensões social e econômica da sustentabilidade, limitando-se à verificação de indicadores apenas da sua dimensão ambiental. A pesquisa está baseada na avaliação de Indicadores de Sustentabilidade Ambiental relacionados à coleta, transporte e disposição do lixo doméstico residual dos pequenos municípios em estudo, e permite uma análise comparativa para medir o impacto ambiental entre a prática usual de vazamentos desses resíduos em lixões e o seu processamento em uma estação comunitária de tratamento mecânico-biológico. Para a análise comparativa de impacto ambiental é adotado, parcialmente, o Método para Avaliação de Sustentabilidade Ambiental de Pequenos Municípios desenvolvido por Carolina Herrmann Coelho-de-Souza (2009), adaptado do método de avaliação da Pegada Ecológica de Wackernagel e Rees (1996). O resultado da pesquisa revelou uma expressiva redução nas Pegadas Ecológicas dos pequenos municípios com a emissão de CO2 equivalente, provenientes da disposição de lixo doméstico residual após o tratamento mecânico-biológico, confirmando a hipótese do trabalho.
This work presents the integrated planning and management of urban solid waste and mechanical-biological treatment, as an alternative to reduce the Ecological Footprints of small municipalities with the landfill gas emissions from residual household waste disposing and thus contributing to a micro-regional policy of environmental sustainability. The studied case is a group of small municipalities in the South of the State of Minas Gerais, which, given the proximity of their urban centres and interdependence among its social, economic and environmental activities, shows suitable conditions for the purposes of this work. This group is formed by the municipalities of Caxambu, Baependi, Conceição do Rio Verde, Cambuquira, Lambari, Campanha and Jesuânia, and is located in a region of natural reserves, agricultural production, historic and ecological tourism, and lacks appropriate environmental public policies for the management of municipal solid waste. It is noteworthy the work s methodology option of approaching the social and economic aspects of Sustainability, focusing on verifying those Indicators only at their environmental aspect. The research is based on the assessment of Environmental Sustainability Indicators related to the collection, transportation and disposal of residual household waste of the small municipalities studied, and allows for a comparative analysis to measure the environmental impact between the regular practice of using open-air uncontrolled landfill (non-treated garbage depository or dumping) and the processing on a community mechanical-biological treatment station.

APA, Harvard, Vancouver, ISO, and other styles

4

Ucekaj, Vladimír. "Analýza možností nakládání s komunálními odpady v rámci mikroregionu." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-233930.

Full text

Abstract:

n accordance with Council Directive 1999/31/EC implemented by Regulation number 294/2005 Sb., Czech Republic has agreed to reduce landfilling of biodegradable material contained in mixed municipal waste (BDMW) by 50 % in comparison with 1995 starting January 1, 2013. This causes several problems to municipalities as the issue of mixed municipal waste (MMW) treatment is not handled at any level of state administration. PhD thesis tackles the question which level of state administration - national, regional, or microregional or municipal - should be responsible for waste treatment and whether it is economical and efficient, or not.

APA, Harvard, Vancouver, ISO, and other styles

5

Bravený, Adam. "Udržitelnost systémů odpadového hospodářství." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231047.

Full text

Abstract:

The thesis proposes a new approach to assess sustainability of waste management systems. In the first part current mixed municipal waste (MSW) management system of the Czech republic is reviewed and promising MSW treatment techniques are introduced. In the second part a summary of literature on Life Cycle Assessment (LCA) approach to assess sustainability of MSW systems is provided. A new sustainability assessment model is proposed by implementing LCA to a current tool called NERUDA used to optimize waste management costing. It is demonstrated how to connect these two concepts in order to aquire a powerful tool for sustainability assessment.

APA, Harvard, Vancouver, ISO, and other styles

6

Kosovska, Halyna. "The Biological Treatment of Organic Food Waste." Thesis, KTH, Industriell ekologi, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32714.

Full text

Abstract:

This Master Thesis “The Biological Treatment of Organic Food Waste” is done in the Master’sProgramme in Sustainable Technology at the Royal Institute of Technology (KTH) in co-operation with the company SRV återvinning AB. The report is dedicated to analyze different biological treatment methods (that is composting andfermentation), which are used for the handling of organic food waste. From this analysis I will suggest the best method or methods for the company SRV återvinning AB (the Södertörn Area inSweden) and for the Yavoriv Region in Ukraine in order to increase the environmental performance and to improve the environmental situation in the regions. To be able to do this, a lot of factors are taking into consideration and are described and discussed in this Thesis Work. General characteristic of the regions, different means of control for organic food waste handling, sorting methods of organic waste, as well as composting and fermentationmethods for treatment of organic waste are described and the advantages and disadvantages of these methods, their treatment and investment costs are distinguished in the Thesis. Different treatment methods are discussed from technical and economical points of view for applying them for the SRV and the Södertörn Area in Sweden and for the Yavoriv Region inUkraine and some solutions for these two regions are suggested. Also some recommendations for further studies are done.
www.ima.kth.se

APA, Harvard, Vancouver, ISO, and other styles

7

Collings, Julia. "Sustainable technology for the biological treatment of waste." Thesis, University of Leicester, 2005. http://hdl.handle.net/2381/30225.

Full text

Abstract:

In this study the microbiological aspects of constructed wetlands were investigated during treatment of industrial effluents, using experimental reed beds in the UK, and also during the installation of reed beds for a commercial company in Ghana. The results showed that the microbiology of a reed bed is affected by the type and concentration of effluent that it is used to treat. Observational study, effluent treatment analysis and microbiological investigation of reed bed substrate, under various loading conditions, revealed that there may be an effect exerted by certain fractions of industrial waste streams that were detrimental to reed flora and the microbiological fauna of the reed beds. Inhibition of the microbial community of the reed bed substrate occurred in the reed beds treating factory effluent which were found to have had a significantly reduced microbial community in terms of colony forming units when compared to the reed beds treating domestic effluent. Treatment efficiency for biological oxygen demand ranged from 48-93%. In the UK, treatment of landfill leachate and tannery effluent showed that reed beds are effective in reducing effluent parameters such as chemical oxygen demand and total nitrogen. Treatment performance for landfill leachate showed total nitrogen reduction ranging from 37-97%. Chemical oxygen demand treatment efficiency ranged from 28-95%. Treatment performance in terms of total nitrogen reduction in tanner effluent ranged from 66-99%, and for chemical oxygen demand 53-87%.

APA, Harvard, Vancouver, ISO, and other styles

8

Surgeoner, Donna Agnes. "Studies of rotating biological contactors." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263488.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Elving, Josefine. "Pathogen inactivation and regrowth in organic waste during biological treatment /." SLU : Dept. of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/11652700.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Amini-Rad, Hassan. "An experimental study of air scour in biological treatment." Thesis, Queen's University Belfast, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336735.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Fradler, Katrin. "Improving bio-electricity production and waste stabilization in Microbial Fuel Cells." Thesis, University of South Wales, 2015. https://pure.southwales.ac.uk/en/studentthesis/improving-bioelectricity-production-and-waste-stabilization-in-microbial-fuel-cells(91c2db18-126b-4610-9bdb-42d7e42ae5e9).html.

Full text

Abstract:

Biological wastewater treatment is typically aerobic and an energy intensive process, mainly due to the required aeration. Alternative sustainable processes are sought, such as Microbial fuel cells (MFC) where electrogenic bacteria can degrade organic matter present in the waste stream while simultaneously generating electricity. MFCs represent an emerging technology which may deliver the capability to reduce the pollution potential of low strength wastewaters (< 1500 mg COD l-1) while generating electricity which could be used to self-power the process. Waste streams high in volatile fatty acids (VFAs) with high conductivity are particularly preferred substrate streams. These may include the effluent from two stage bio-hydrogen and bio-methane systems, which in this study were treated in a four-module tubular MFC (V=1 l) to reduce the chemical oxygen demand (COD) and recover further energy from the substrate. It was shown that the power increased with increasing organic loading rate (0.036-0.572 g sCOD l-1 d-1), but COD removal efficiency decreased. The Coulombic Efficiency (CE) was found to decrease significantly at OLR ˃ 0.6 g sCOD l-1 d-1 and the energy recovery was 92.95 J l-1 (OLR=0.572 g sCOD l-1 d-1). Also, wash-down waters from a chilled food producing company were treated in the same tubular MFC, reducing the soluble COD content by 84.8%. The low power (≈ 30 W m-3) and cell potential (≈ 0.5 V) makes it necessary to investigate methods such as external capacitors, DC/DC converters or serial and parallel connection to improve the power quality. In this thesis, the use of the intrinsic capacitance was tested by switched mode, open and closed circuit (OC/CC) operation of a 2-module tubular MFC with high surface area carbon veil anode. The charge accumulated during OC and released when switched to CC was dependent on the external resistor (R = 100-3 kΩ) and duty cycle. Short period OC/CC switching further increased potential due to the pseudo-capacitance of the reactor, but only at the expense of energy efficiency, compared to continuous operation (CC) under constant load. Another approach to enhance the practical implementation of MFCs is integration with other processes such as reverse electrodialysis to increase MFC’s cell potential or e.g. desalination. In this study a MFC was integrated with supported liquid membrane technology (SLM) for the first time, for the removal of metal ions of wastewater. A three chamber reactor, with a common cathode/feed phase containing 400 mg Zn2+ l-1, enabled V the simultaneous treatment of organic- and heavy metal containing wastewaters. The MFC/SLM combination produces a synergistic effect which enhances the power performance of the MFC significantly; 0.233 mW compared to 0.094 mW in the control. It is shown that the 165±7 mV difference between the MFC/SLM system and the MFC control is partially attributable to the lower cathode pH in the integrated system experiment, the consequent lower activation overpotential and higher oxygen reduction potential. The system demonstrates that within 72 h, 93±4% of the zinc ions are removed from the feed phase. A further study, with continuously operated cathode/feed chamber (100 mg Zn2+ l-1), showed that an enhanced effect on increasing cell potential was possible and could also be maintained in continuous operation.

APA, Harvard, Vancouver, ISO, and other styles

12

Harris, Ivor E. "The effects of biological waste treatment by acidogenic fermentation on certain pathogens /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18146.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Diebels, Jesper. "Feasibility study of biological treatment of organic waste in Tsumeb Municipality, Namibia." Thesis, KTH, Industriell ekologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-150884.

Full text

Abstract:

This study is part of a larger project in which the Tsumeb municipality, Falun municipality and Falu Energi & Vatten AB work together to change the currently used controlled waste dumping site in Tsumeb into a sanitary landfill. This study aims to recommend a MSWM solution that will divert the organic waste from going to the landfill. The study consist out of a literature study in order to establish a theoretical background for the MSWM solution; a field study in which the current waste flows of Tsumeb were quantified, by using current data, and characterized, by performing a hand-picking analyses according to the UNEP methodology; and an analyses section in which an appropriate MWSM solution was proposed. The current waste consist out of 70% sand and stones, 17% grass and leaves, 6% prunings and trimmings, 4% sewage sludge, 3% branches and stumps, and 1% of other waste. This paper concludes that 99% of the organic waste in Tsumeb can be recycled, by using it as covering material, as biofuel and turning it into compost. This paper also shows that there is a potential for Tsumeb to start economically sound composting facility.

APA, Harvard, Vancouver, ISO, and other styles

14

Roshdieh, Rana. "Alternative Waste Treatment System for Poultry Processing Plants." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/46421.

Full text

Abstract:

The objective of this research was to design an alternative wastewater treatment system for turkey processing plants to recover energy and reduce N and P to allowable discharge levels. The objective included: 1. Determine the quantity and quality of biogas produced from the turkey processing wastewater (TPW) and COD reduction efficiency. 2. Design a waste treatment system and validate proof of concept for simultaneous P and N removal with a goal of attaining effluent concentrations of 0.1 mg/L and 4 mg/L, for P and N, respectively. A lab-scale complete mixed anaerobic digester was used for turkey processing wastewater (TPW) digestion and biogas recovery running for 6 months. Along with the anaerobic digester, a two-sludge system called A2N-SBR consisting of an anaerobic-anoxic sequencing batch reactor and an attached growth post-nitrification reactor was added for biological nitrogen and phosphorus removal running for 3 months. Biogas production yields of 778 + 89 mL/gVSadded and 951.30 mL/g COD were obtained through anaerobic digestion. Also, an energy balance was conducted on a pilot scale digester for a turkey processing plant with wastewater production of 2160 m3/d and using a combined heat and power (CHP) enginefor conversion of biogas to heat and electricity. Although the biogas yield achieved in a complete mixed reactor was relatively lower than yields obtained in previous studies using reactors such as UASB, still a complete mixed reactor can be a good choice for biogas recovery from TPW and can be used for codigestion with some specific turkey processing byproducts for biogas recovery. Nitrogen and phosphorus removal in the A2N-SBR system were 47% and 75%, respectively, and during the study the nitrogen and phosphorus removal mean concentration in effluent did not meet the nutrient limits specified in the objectives. Average TP and TN in the effluent were 3.2 mg/L and 137 mg/L, respectively. Throughout the study, the nitrification reactor biofilm was not completely developed. Incomplete nitrification and poor settling might be the reasons that quality obtained in effluent was low. To improve the process condition in A2N-SBR, online monitoring of pH, dissolved oxygen (DO) and oxidation reduction potential (ORP) can help to optimize each stage in the SBR and stages duration can be set based on the results.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

15

Batarseh, Eyad. "Chemical and Biological Treatment of Mature Landfill Leachate." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2698.

Full text

Abstract:

This dissertation is about treatment of the nonbiodegradable organic content of landfill leachate by chemical oxidation combined with biological treatment. It is divided into three parts. In the first part, ferrate was compared to Fenton's reagent for the purpose of removing non-biodegradable organic compounds from mature leachate. Oxidation conditions (time, pH, and dose) were optimized to yield maximum organic removal using two leachate samples from 20 and 12-year old solid waste cells. Results from this research demonstrated that ferrate and Fenton's reagent had similar optimum pH ranges (3-5), but different organic removal capacities, ranging from 54 to 79 % of initial leachate organic contents. An advantage of ferrate was that it was relatively effective over a wide pH range (Fenton's reagent lost its reactivity outside optimum pH range). Advantages associated with Fenton's reagent include a higher organic removal capacity, production of more oxidized organic compounds (measured as chemical oxygen demand/dissolved organic carbon), and production of more biodegradable byproducts (measured as 5-day biochemical oxygen demand/chemical oxygen demand). Finally, both treatments were found to oxidize larger molecules (>1000 dalton) and produce smaller molecules, as indicated by an increase in smaller molecule contribution to organic carbon. In part two, effects of Fenton's reagent treatment on biodegradability of three landfill leachates collected from a Florida landfill were evaluated using biochemical oxygen demand (BOD), biochemical methane potential (BMP), and tertamethylammonium hydroxide (TMAH) thermochemolysis gas chromatography/mass spectrometry (GC/MS). The hypothesis was that Fenton's reagent will remove refractory compounds that inhibit biodegradation and will produce smaller, more biodegradable organic molecules which will result in an increase in BOD and BMP values. Both BOD and BMP results demonstrated that Fenton's reagent treatment did not convert mature leachate to biodegradable leachate, as indicated by a low BOD5 expressed as C /dissolved organic carbon (DOC) ratio of almost 0.15 in treated samples and a low net methane production / theoretical methane potential (less than 0.15). Ultimate BOD only slightly increased. However the first-order BOD reaction rate increased by more than five fold, suggesting that Fenton's reagent removed refractory and inhibitory compounds. BMP results demonstrated that the ratio of CO2/CH4 produced during anaerobic biodegradation did not increase in treated leachate (compared to untreated), indicating that small biodegradable organic acids produced by oxidation were removed by coagulation promoted by Fenton's reagent. Finally, the TMAH thermochemolysis results showed that several of the refractory and inhibitory compounds were detected fewer times in treated samples and that carboxylic acids did not appear in treated samples. In the third part of this dissertation the application of flushing/Fenton's reagent oxidation to produce sustainable solid waste cells was evaluated. A treatment similar to pump and treat process utilizing Fenton's reagent on-site treated leachate combined with in-situ aeration was proposed. Treated leachate would be recycled to the landfill cell flushes releasable nonbiodegradable carbon from the cell and oxidizes it externally. This technique was demonstrated to have treatment cost and time benefits over other alternatives for producing completely stable solid waste cells such as anaerobic flushing and biological and/or mechanical pretreatment of solid waste (used in the EU).
Ph.D.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engineering

APA, Harvard, Vancouver, ISO, and other styles

16

Holtman, Gareth Alistair. "Design, installation, and assessment of a biological winery wastewater treatment system." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2573.

Full text

Abstract:

Thesis (MTech (Civil Engineering))--Cape Peninsula University of Technology, 2017.
Currently in South Africa, most wastewater from small cellars is pH-adjusted and disposed of via land irrigation. This practice can lead to environmental degradation. There is a need for low cost, low maintenance solutions for the treatment of cellar effluent. Constructed wetlands provide such an option. However, the use of plants is problematic because winery effluent can be phytotoxic. After successful initial laboratory-scale experiments, an in-situ pilot scale biological sand filter (unplanted constructed wetland) system was designed, installed, and used to treat effluent from a small winery in the Western Cape, South Africa. The system is off-grid, totally self-regulating, and uses a modular approach which allows for the addition and subtraction of filter modules within the system to alter treatment capacity, retention time and/or rest filter modules. The system can be easily integrated into existing settling basins and/or retention ponds at small wineries. The biological sand filter was operational for 610 days, and showed promising results. The average chemical oxygen demand removal efficiency was 81% (range: 44-98%) with an average effluent of 324 mg/L, and an average flow rate of 413 L/day after the acclimation (start-up) period. The average hydraulic loading rate after the initial start-up period was 143 L/m3 sand day-1 (range: 67-222/m3 sand day-1), with an organic loading rate of 205 gCOD/m3 of sand day-1 (range: 83-338 gCOD/m3 sand day-1) which resulted in an organic removal rate of 164 gCOD/m3 of sand day-1. There was an average of 67% removal of total phenolics, thereby reducing the potential phytotoxicity of the effluent. In addition, there was a 1.6 times increase in calcium concentration, a 29% decrease in the average sodium adsorption ratio, and complete passive neutralisation of the acidic winery wastewater (final effluent pH range: 6.63 – 8.14. The findings of this study compare well with previous laboratory studies conducted with synthetic and authentic winery effluent. The system can potentially provide a low cost, energy efficient, low maintenance, sustainable means of treating cellar effluent at small wineries. Uptake of this technology may alleviate environmental degradation caused by irrigating land with inadequately treated effluent.

APA, Harvard, Vancouver, ISO, and other styles

17

Smith, Jennifer Mary. "Detection of Ammonia-Oxidizing Beta-Proteobacteria in Swine Waste Treatment Systems." NCSU, 2004. http://www.lib.ncsu.edu/theses/available/etd-09162004-173714/.

Full text

Abstract:

In order to obtain supporting evidence for biological denitrification in anaerobic lagoons degenerate ?Ò-Proteobacterial AOB primers were used to create and sequence clone libraries to detect the presence of ammonia-oxidizing bacteria at three field sites. Although there were PCR products from almost all samples, the clone libraries that were created show that not all PCR reactions produce only PCR products from ammonia-oxidizing bacteria. However, these primers did verify the presence of ammonia-oxidizers at one site, although their presence was not verified at the other sites. The presence of ammonia-oxidizers at the Battelle site implies that aerobic ammonia-oxidation is occurring. Clones were created and sequenced that were significantly different from other known sequences and tended to form very closely related phylogenetic groups. These phylogenetic groups were not isolated to one field site, and often more than one site had representatives in a closely related group. Future research in this field includes the design of new primer sets based on the sequences of the nitrifying bacteria clones reported in this research, creation of enrichment cultures, and use of new primers for fluorescent in situ hybridization.

APA, Harvard, Vancouver, ISO, and other styles

18

Raabe, Maren [Verfasser]. "Occurrence and Synthesis of Methylated Metal(loid) Compounds during Biological Waste Treatment / Maren Raabe." Aachen : Shaker, 2007. http://d-nb.info/1166512363/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Kirkpatrick, Allison Paige. "Evaluation of an Attached Growth Organic Media Bioreactor for Swine Waste Treatment and Odor Abatement." MSSTATE, 2001. http://sun.library.msstate.edu/ETD-db/theses/available/etd-08102001-000815/.

Full text

Abstract:

The objective of this study was to determine if an organic media attached growth bioreactor could effectively be used as a means of odor control for swine waste. The pilot-scale attached growth bioreactor system was evaluated against a standard pit recharge system, which served as the control. Performance was based on water quality testing, odor assessments by a human sensory panel, and air phase measurements of ammonia and hydrogen sulfide. The affect of aeration on the system was also evaluated, along with various types of organic media (kenaf, hardwood mulch, and corncobs). Overall, the bioreactor systems were effective in reducing orthophosphate, COD, volatile acids, and phenol concentrations as compared to the control. The bioreactor systems were not effective in reducing the conductivity, ammonia or total solids concentration of the wastewater. With the exception of the corncob media, all bioreactor systems significantly reduced the overall odor intensity and the fecal characteristic of the wastewater as compared to the control system.

APA, Harvard, Vancouver, ISO, and other styles

20

Bennett, Todd Alan. "Evaluation of Bench-Scale Sequencing Batch Reactor Swine Waste Treatment Under Continuous and Cyclic Aeration." NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-04242007-234951/.

Full text

Abstract:

The objectives of this project were to develop operating conditions for a bench-scale sequencing batch reactor to match the design of a full-scale sequencing batch reactor system for treating swine waste and to determine the effects of continuous, low oxygen versus cyclic aeration schemes on sequencing batch reactor system performance. The low aeration technique was intended to develop conditions for low oxygen nitrification and simultaneous nitrification and denitrification so that a comparison could be made to a typical cyclic aeration reactor for biological nitrogen and phosphorus removal. The performance of the two reactor configurations was measured by the settling efficiency, mass removal efficiency, and accumulation of chemical oxygen demand (COD), suspended solids (SS), total Kjeldahl nitrogen (TKN), and total phosphorus (TP). The performance of the reactors did not meet expectations due to excessive loading and source inconsistency. Operational changes to the solids wasting mechanism and to the cyclic aeration system were made during the experiment in an attempt to stimulate reactor performance, which provided insight into the responses of the two types of reactors to these changes. The performance of the continuous aeration reactors met or exceeded the performance of the cyclic aeration reactors, while receiving a 73% lower supply of oxygen. The results support the potential for equipment and energy savings by utilizing low-oxygen continuous aeration for the treatment of swine waste with sequencing batch reactors.

APA, Harvard, Vancouver, ISO, and other styles

21

Mbwele, Lydia Ambakisye. "Microbial Phosphorus Removal in Waste Stabilisation Pond Wastewater Treatment Systems." Licentiate thesis, KTH, School of Biotechnology (BIO), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3876.

Full text

Abstract:

Waste Stabilisation Ponds (WSPs) are characterised by low phosphorus (P) removal capacity. Heterotrophic bacteria are principal microbial agents in WSPs in addition to algae. As treatment proceeds in WSPs, algal growth increases and pH rises, this has lead to believe that P removal is mainly through sedimentation as organic P algal biomass and precipitation as inorganic P. In activated sludge treatment plants (AS), microbial P removal has been improved and is termed as enhanced biological phosphorus removal. There was a need to establish whether it was possible to enhance P removal in WSPs. A performance assessment of pond system at the University of Dare s Salaam (UDSM), Tanzania, has shown that 90% of the P removed was in the primary pond (facultative) and the rest in the maturation pond (aerobic).

In these studies, a pure strain A. hydrophyla was isolated from an activated sludge wastewater treatment plant in Sweden. This plant has a train that functions with enhanced biological phosphorus removal. The strain was tested for P uptake in minimal media supplemented with glucose, succinate or acetate, grown aerobically and anaerobically/aerobically. This strain was able to take up P without having been subjected to the anaerobic phase. It was observed that P uptake was enhanced after the anaerobic phase with media supplemented with glucose, but not with succinate or acetate. Phosphorus uptake repeatedly followed the bacterial growth pattern with correlation coefficients of more than 95%. Therefore P removal has a direct correlation with bacterial growth.

Two isolates Acinetobacter sp. (isolated from the primary facultative pond) and E .coli (isolated from the maturation pond) were obtained from a tropical WSP treatment system at the UDSM. They were subjected to aerobic P uptake experiment similar to those of A.hydrophyla. The uptake per unit absorbance of bacterial growth was found to be comparable to that of A.hydrophyla, isolated from AS. These results showed that heterotrophic activity is important in WSPs. It is possible to enhance P removal in these systems by designing the primary ponds for maximum heterotrophic activity and probably enrichment.

APA, Harvard, Vancouver, ISO, and other styles

22

MACOMBER, JEFF RAYMOND. "EFFECTS OF SOLIDS RETENTION TIME ON THE TREATMENT OF SYNTHETIC WASTEWATER USING A MEMBRANE BIOREACTOR." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin981401531.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Wallace, Trevor Haig. "Biological Treatment of a Synthetic Dye Water and an Industrial Textile Wastewater Containing Azo Dye Compounds." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/34115.

Full text

Abstract:

In this research, the ability of anaerobic and aerobic biological sludges to reduce and stabilize azo dye compounds was studied. Synthetic dye solutions and an industrial textile wastewater were both treated using anaerobic and aerobic biomass, separately and in sequential step-treatment processes. The primary objective was to reduce the wastewater color to an intensity that complies with the Virginia Pollutant Discharge Elimination System (VPDES) permit level. This level is set at 300 American Dye Manufactures Institute (ADMI) units. Further objectives were to achieve reductions in the total kjehdal nitrogen (TKN) and total organic carbon (TOC) in the wastewater. Anaerobic and aerobic treatment systems were both effective in reducing the wastewater color; however, anaerobic treatment generally produced the greatest color removal. Anaerobic/aerobic (ANA/AER) sequential step-treatment provided the best reductions in ADMI color, TKN and TOC. Anaerobic/aerobic/anaerobic/aerobic (ANA/AER/ANA/AER) sequential step-treatment did not yield greater reductions in ADMI color, TKN, or TOC as compared to ANA/AER sequential step-treatment.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

24

Challans, Penelope. "Optimisation and modelling of pyrolysis processes focused on the treatment of municipal solid waste scaled towards decentralised energy from waste systems." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/73372/.

Full text

Abstract:

Energy from Waste (EfW) technologies are beneficial for both energy generation and as a waste management option. However they face significant challenges due to the heterogeneous nature of municipal solid waste. The overall aim of the research reported in this thesis was therefore to explore some of the problems which hinder the development of commercial scale EfW technologies. A laboratory scale pyrolysis reaction rig has been developed to investigate the effect of temperature, residence time and fuel type on the pyrolysis products. Investigations were also undertaken to establish the composition of gas produced from the pyrolysis of typical waste feedstocks in two commercial scale pyrolysis rigs. An empirical model has been developed to predict the pyrolysis behaviours on a larger scale and comparisons have been made with data from the commercial scale rigs. The research findings showed that the majority of the reduction of mass during pyrolysis occurred within the first 5-10 minutes with a loss of up to 70 % at 550 °C and up to 77 % at 700 °C for paper, newspaper and cardboard. Paper, newspaper and cardboard behaved similarly with solid, liquid and gaseous fractions of approximately 33 %, 53 % and 13 % respectively. Products from the plastics components varied significantly; PET produced the highest gaseous products (42 %) and HDPE produced the highest solid products (45 %). An increase in pyrolysis temperature increased the gaseous products from paper to 34 % to the detriment of liquid and solid yields. The main gases produced from the pyrolysis were found to be CO2, CO and H2, except for the pyrolysis of PVC where the main gases produced, from the high content of hydrochloride, were not identified in this study. An increase in pyrolysis temperature was found to increase the production of CO and H2. The gas produced from commercial rig 1 mostly consisted of CO2 due to the low temperature and the addition of air to the pyrolysis chamber. The gas produced from commercial rig 2 consisted of high volumes of CO and H2 suggesting the rig was operating at a temperature above 550 °C. An empirical model was developed based on laboratory data to allow prediction the effect of a change in MSW composition on the pyrolysis gas. It was found that the addition of newspaper to a waste mix led to a higher production of CO and therefore a higher HHV. In general, the results of this study suggest that the laboratory scale pyrolysis rig used in this study and the empirical models developed, can be employed to predict the behaviour of larger scale commercial pyrolysis systems. However, further experimental investigation on the pyrolysis behaviours of mixed waste samples, especially plastic fractions, is hereby proposed.

APA, Harvard, Vancouver, ISO, and other styles

25

Wijesinghe, D. W. N. "Optimization of bio-methane production process for combined treatment of sewage & municipal solid waste." Thesis, KTH, Energiteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209910.

Full text

Abstract:

Handling solid waste such as municipal solid waste (MSW) has become a booming problem in highly populated urban areas. Even though it has a high potential of biogas generation in anaerobic digestion, it is not that successful as a single substrate. The early researches proved that it can be treated combined with sewage sludge as a co-digestion process. This study was done to find the best performing mixing ratio of MSW and sewage sludge (SS) which gives maximum bio methane output. In this study three mixing ratios for MSW to SS were used as 50:50, 60:40, and 80:20. The retention time was selected as 20 days and the process was continued for 11 days. The highest cumulative methane production was observed at 80:20 (MSW: SS) mixing ratio as 2957.8 ml of methane. The methane and carbon dioxide content in gas was measured by using gas chromatograph. Highest Total Volatile Solids reduction also recorded at 80: 20 (MSW: SS) ratio as 57.32% after 11 days. The best soluble COD reduction, 95.19% and COD reduction, 36.85% also recorded at 80:20 mixing ratio.

APA, Harvard, Vancouver, ISO, and other styles

26

Brazil, Brian Ligar. "Evaluation of an Effluent Treatment Strategy to Control Nitrogen From a Recirculating Aquaculture Facility." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35413.

Full text

Abstract:

The ability of a self-contained denitrification system, using fermentation products from waste fish solids, to maintain reliable performance was studied. Denitrification performance was described kinetically and stoichiometrically under different initial nitrate-nitrogen and soluble organic carbon to nitrate-nitrogen ratios. Characterization of soluble organic carbon (measured as soluble chemical oxygen demand, sCOD) indicated that volatile fatty acids (VFA) were generated during the fermentation of the waste fish solids. The results from batch experiments showed that over the range of initial nitrate concentrations studied, complete denitrification was achieved within 6 hrs. sCOD, nitrite, and nitrate profiles across several batch experiments showed that transient nitrite accumulations occurred, but the maximum measured concentrations never completely inhibited nitrate removal. The results suggested that the rate of denitrification was influenced by the initial sCOD to nitrate-nitrogen ratio when transient nitrite concentrations remained below 20 mg/L. However, when nitrite-nitrogen exceeded 25 mg/L, the rate of denitrification was negatively correlated with the maximum measured nitrite-nitrogen concentration. The stoichiometric carbon requirement was not correlated to any parameters believed to influence carbon consumption. After complete denitrification was achieved residual sCOD was still measured, which could not be identified as VFAs. Batch aerobic treatment of denitrified effluent resulted in a 60 to 70 % removal of the residual sCOD when allowed to react for 8 days. It was further determined that the residual sCOD exerted an oxygen of 5.81 on g COD/g C. Additional studies were conducted to maximize sCOD production during fermentation. Increasing the fermentation temperature from 28 oC to 40 oC facilitated a 36 % increase in the specific sCOD production rate (g sCOD/ g fish solids applied). In addition to sCOD production, ammonia production increased 20 % when the fermentation was conducted at the elevated temperature. An analysis comparing the cost of methanol addition to support denitrification to the cost associated with fermenting waste fish solids indicated that supplementing fermentation products with methanol resulted in the least costly strategy for promoting denitrification of an aquaculture waste stream.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

27

Giles, Hamilton. "Biotransformation potential of phytosterols in biological treatment systems under various redox conditions." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48993.

Full text

Abstract:

Phytosterols are naturally occurring compounds which regulate membrane fluidity and serve as hormone precursors in plants. They also have the potential to cause endocrine disturbances in aquatic animals at concentrations as low as 10 µg/L. Wastewaters from several industries which process plant matter can contain phytosterols at concentrations in excess of the above-stated level. Despite their endocrine disruption potential, very little is known about phytosterol physical properties and their biotransformation potential in biological treatment systems. Aerated stabilization basins (ASBs) are common biological treatment systems in North American pulp and paper mills. ASBs are large open lagoons which use tapered surface aeration to remove COD and prevent sulfate reduction in the water column. Phytosterols are released from wood during the pulping process and a small fraction enters the wastewater stream during washing of the pulp. Therefore, phytosterols may be exposed to aerobic or anaerobic environments depending on their solubility and solid-liquid partitioning behavior. The overall objective of this research was to systematically and quantitatively assess the biotransformation potential of phytosterols in biological treatment systems and to examine conditions leading to reduction of these compounds in wastewater effluent streams. The results of this research showed that phytosterols are sparingly soluble with aqueous solubility below 1 µg/L when present as a mixture. Phytosterols have a strong affinity to adsorb to solids and dissolved organic matter. The affinity for aerobic biomass was greater than for wastewater solids. The stigmasterol desorption rate and extent from wastewater solids increased with an increase in pH from 5 or 7 to 9. Phytosterols were biotransformed under aerobic conditions but not under sulfate-reducing or methanogenic conditions by stock cultures developed in this study. Biotransformation under nitrate-reducing conditions could not be confirmed conclusively. The continuous-flow system was successful in removing 72 to 96% of phytosterols. Biotransformation accounted for 23, 14 and 41 % of campesterol, stigmasterol and β-sitosterol removal, respectively. Phytosterols accumulated in the reactor sediment and accounted for 97 % of the total phytosterols remaining in the system. Phytosterols can be removed from wastewater streams during biological treatment by a combination of biotransformation and solids partitioning and control of system pH, DO and available carbon and energy sources can increase the degree of phytosterols removal. The results of this research can be used to engineer effective biological treatment systems for the removal of phytosterols from pulp mill wastewaters and other phytosterol-bearing wastewater streams.

APA, Harvard, Vancouver, ISO, and other styles

28

Palazolo, Paul Joseph. "Use of genetic algorithms in bounded search for design of biological nitrification/denitrification waste treatment systems." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/32777.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Tam, Kawai 1969. "Removal of multiple substrates in a mixed culture process for the treatment of brewery wastewater." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38421.

Full text

Abstract:

The removal of multiple substrates in a defined mixed culture process was investigated in the treatment of brewery wastewater. The study was conducted using both batch and a semi-continuous reactor system called self-cycling fermentation. Batch experiments were conducted using a synthetic brewery wastewater containing glucose, ethanol and maltose. Activated sludge from a municipal wastewater treatment plant was acclimatized in the synthetic brewery wastewater. The microbes capable of degrading this wastewater were analyzed by a combination of microscopy, spread plating, and Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) and identified as Acinetobacter sp., Enterobacter sp. and Candida sp. From the pure culture batch experiments, it was determined that Enterobacter could degrade glucose and maltose but no ethanol, while Acinetobacter and Candida could degrade all three carbon sources. In mixed culture batch experiments, Enterobacter was dominant in degrading the sugar concentrations to levels permissible for Acinetobacter to degrade ethanol. PCR-DGGE was found to be effective in identifying the dominant species but selective carbon source plating was required to determine viability and track the population dynamics. Kinetic experiments were carried out in a semi-continuous, self-cycling fermentation process using the defined mixed culture in media containing glucose and various initial concentrations of ethanol and maltose. The overall rate of substrate removal was attributable to both the suspended culture and the biofilm formed during the process. A rate expression was developed for this system for the range of substrate concentrations tested. The data indicated that substrate removal by the suspended culture was a function of only the biomass concentration. However, substrate removal by the biofilm was found to be limited to the surface cells and determined to be a function of substrate concentration only.

APA, Harvard, Vancouver, ISO, and other styles

30

Nguyen, Anh-Long. "Application of self-cycling fermentation to a fixed-film reactor for the treatment of brewery wastewater." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0007/MQ44230.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Smuts, Lizl. "Investigation into the biological removal of sulphate from ethanol distillery wastewater using sulphate-reducing prokaryotes." Thesis, Rhodes University, 2005. http://hdl.handle.net/10962/d1004000.

Full text

Abstract:

Ethanol production wastewater is known to be toxic, and is not easily biodegradable. It also consists of a variety of coloured components adding to the complex composition of this wastewater. Disposal of this wastewater into water courses is not recommended and yet is performed all over the world. Investigation of this wastewater found that there was a high concentration of sulphate which, in the presence of sulphate-reducing prokaryotes can cause sulphide corrosion of cement. The concentration of sulphate in the wastewater was approximately 2770 mg/L. It was also found that the wastewater pH was very low and discharge of the wastewater into the wastewater treatment works caused a negative impact on the overall quality of the final wastewater discharged to sea. It was found using FISH techniques that there were no sulphate-reducing prokaryotes present in the wastewaters but that a sulphate-reducing population existed on the sewer wall. An anaerobic contact process was designed to treat this wastewater targeting sulphate reduction to sulphide, to be converted into elemental sulphur and to increase the wastewater pH. The process did not achieve this aim and only approximately 20-30 % reduction in sulphate from the wastewater was achieved with little to no change in the pH. A 95 % reduction in sulphate concentration was needed in order to reach acceptable discharge limits. Sulphate reduction could not be carried out, even under ideal laboratory conditions. It was found that the barrier causing the digester failure was the high concentration of phenols present in the wastewater (3.3 g/L) together with the production of high concentrations of volatile fatty acids (on average 13 g acetic/L). These two components are known to cause digester failure, especially phenols, and phenols are usually only degraded by fungal species. It was concluded that the wastewater itself was not amenable to this method of biological treatment.

APA, Harvard, Vancouver, ISO, and other styles

32

Wolfe, Christopher L. "Biological and physical treatment of crab processing industry wastewaters." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-08042009-040526/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Ramirez, Gomez Camilo. "A techno-economicGIS-based model for waste water treatment and reuse feasibility in the North Western Sahara Aquifer System." Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-244449.

Full text

Abstract:

Water security represents a main challenge in the quest for sustainable development and stability worldwide. Often, such security is closely linked with the demand of water for agricultural irrigation, as it repre-sents the major share of human water withdrawals. The North Western Sahara Aquifer System (NWSAS), is a large aquifer system spreading through three North African countries: Algeria, Tunisia and Libya. It is formed by two superposed groundwater reservoirs, constituting the main sources of fresh water access in the region. To cope with the water demand and alleviate water resources exploitation, Treated Wastewater (TWW) is emerging as a promising solution for the region. This master thesis focused on the development of a GIS-based methodology to asses the techno-economic feasibility of wastewater reclaim, treatment and reuse for crop irrigation in the NWSAS region, considering groundwa-ter quality and depletion, electrical energy requirements and Levelised Cost of Water (LCOW) as main assessment parameters. Such model enables the evaluation, under different scenarios, of the impact that new policies, technologies and measures can have in the overall system. Nine wastewater treatment technologies were analysed, under eight dif-ferent scenarios. The scenarios were constructed based on population water requirements per capita and the behaviour of farmers towards different irrigation water price regimes. The least-cost technologies found, presented a tradeoff between the wastewater treatment capac-ity and the technology chosen, which approximates to the behaviour found in reality. The outcomes of the analysis, evidenced the current medium-to-high stress of the groundwater resource, which is trending to worsen. Moreover, the reuse of treated wastewater in agricultural irrigation, showed to be a viable option for reducing the water stress of the basin. However, to preserve the water resource, measures as better water pricing mechanisms, management strategies to improve water productivity and adoption of more efficient irrigation schemes may be needed. Furthermore, the energy-for-water needs were evaluated. Pumping energy represents by far the major user of electrical energy in the region and the treatment and reuse of waste water, showed to be useful to reduce the dependency on pumped resources, reducing as well the energy-for-water needs. Moreover, the effect of changes in salinity content and depth to groundwater levels, showed substan-tial effects on the energy requirements for desalination and pumping respectively, which can jeopardize the economic sustainability of the agricultural practice in the basin.
Vattenskydd utgör en viktig utmaning för strävan efter hållbar ut-veckling och stabilitet över hela världen. Ofta är sådan säkerhet nära kopplad till efterfrågan på vatten för bevattning av jordbruket, eftersom den utgör den största delen av mänskliga vattentillträden. Nordvästra Sahara Aquifer System (NWSAS) är ett stort akvifer system som sprids genom tre nordafrikanska länder: Algeriet, Tunisien och Libyen. Den bildas av två överlagrade grundvattenreservoar, som utgör huvudkäl-lorna för tillgång till färskvatten i regionen. För att klara av efterfrå-gan på vatten och minska vattenresursutnyttjandet växer behandlat avloppsvatten (TWW) som en lovande lösning för regionen. Denna masterprojekt fokuserade på utveckling av en GIS-baserad metodik för att bedöma den tekniskt ekonomiska möjligheten att återvinna, be-handla och återanvända avloppsvatten i NWSAS-regionen med hänsyn till grundvattenkvalitet och uttömning, elkrav och nivåvattenkostnad (LCOW) som huvudbedömningsparametrar. En sådan modell möjlig-gör utvärdering, i olika scenarier, av den inverkan som nya policyer, tekniker och åtgärder kan ha i det övergripande systemet. Nio avloppsreningstekniker analyserades, under åtta olika scenarier. Scenarierna byggdes utifrån befolkningens vattenbehov per capita och beteendet hos bönderna mot olika bevattningssystem för bevattning. Den billigaste teknologin som hittades presenterade en avvägning mel-lan avloppsvattenbehandlingsförmågan och den valda teknologin, vil-ket approximerar det beteende som finns i verkligheten. Resultatet av analysen visade den aktuella medellånga stressen i grundvattenresur-sen, som tenderar att förvärras. Dessutom visade återanvändningen av behandlat avloppsvatten i jordbrukssköljning att det var ett lönsamt al-ternativ för att minska bassängens vattenbelastning. Men för att bevara vattenresursen kan åtgärder som bättre vattenprissättningsmekanis-mer behövas, ledningsstrategier för att förbättra vattenproduktiviteten och antagandet av effektivare bevattningssystem. Vidare utvärderades energibehovet. Pumpenergi representerar den överlägset största an-vändaren av elenergi i regionen och behandling och återanvändning av avloppsvatten visade sig vara användbar för att minska beroendet av pumpade resurser, vilket också minskar behovet av energi för vat-ten. Dessutom visade effekten av förändringar i salthaltens innehåll och djup till grundvattennivån betydande effekter på energibehovet för avsaltning och pumpning, vilket kan äventyra den ekonomiska hållbarheten hos jordbrukspraxis i bassängen.

APA, Harvard, Vancouver, ISO, and other styles

34

Bergseije, Victor. "Effects of Heat Transfer Fluid from District Heating Networks on Activated Sludge : A respirometric analysis using a dilution series to assess disruption of biological treatment processes in wastewater treatment facilities." Thesis, Linnéuniversitetet, Institutionen för biologi och miljö (BOM), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-34038.

Full text

Abstract:

District heating has a long standing tradition in Sweden and today it is the most common way of producing and transporting heat. A District heating system (DH system) is divided into three parts: a production facility, distribution network (DH network) and one more heat stations. The heat produced in the facilities is distributed to the customers via a heat transfer medium, usually water (DH water), in piping networks that make up the DH network. The heat is transferred to the customers via the heat exchanger at which point they can use it as heated tap water or for heating purposes. The DH networks are often constructed in steel as it is cheap and a relatively resistant material. However it has the disadvantages of corrosion and expansions when it is exposed high temperatures which lead to damages in the DH network resulting in loss of the DH water, this is an unavoidable occurrence in any DH network. This results in addition of pollutants by leakages into the DH network or with the water that is used to compensate for the losses. The pollutants cause further corrosion, leading to metal contamination, and more damages on the DH network meaning there is a continuous degradation. Therefore various treatments are used to clean and ascertain an acceptable chemical environment in the DH systems. These treatments are effective but not at a level which is required so many chemicals are used to enhance the treatment of the water. Some of these are known to be toxic to humans and water ecosystems. As leakages are abundant and often end up in the WWTPs of the concerned municipality, which often have troubles with disturbances of the biological treatment, it was decided that an assessment of the toxic effects that DH water pose on activated sludge was to be investigated. This was done by testing water from two DH networks, Växjö and Kalmar, on the same activated sludge obtained from Tegelviken WWTP in Kalmar. A respirometric bioassay approach established by the Organization for Economic Co-operation and Development (OECD), OECD standard 209; OECD Guidelines for the Testing of Chemicals was used with changes made to exposure and measuring time as this decrease the risk of misinterpretation of the results. A dilution series using different concentrations (6.25%, 25% and 100%) of DH water was tested and compered to a blank control samples containing only activated sludge. Assessment of toxicity on total oxidation, oxidation carbon and oxidation of nitrogen was made. To get some idea of what might cause toxic effect samples of the waters was sent to outside laboratories for analyses of metals. The result from the bioassay and metal analysis was used to formulate risk factors associated with a DH water spill and exposure to WWTPs. It was found that both DH waters have a significant inhibition on nitrification in WWTPs. The DH water from Kalmar exhibited similar toxicity dynamics, roughly 20% inhibition, despite large differences in concentration. The DH water from Växjö showed a negative correlation between an increase in concentration of DH water and toxicity, 74% for the lowest concentration and 11% for the highest. The metal analysis concluded that there was no abundance of metal contamination which led to the inference that toxicity is probably caused by the chemicals used for treatment. This poses a great risk for the Baltic Ocean as many WWTPs release their treated water directly into water courses with a short detention time before reaching the sea.

APA, Harvard, Vancouver, ISO, and other styles

35

Moore, Bronwyn Ann. "Investigation into the technical feasibility of biological treatment of precious metal refining wastewater." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1002013.

Full text

Abstract:

The hydrometallurgical refining of platinum group metals results in large volumes of liquid waste that requires suitable treatment before any disposal can be contemplated. The wastewater streams are characterized by extremes of pH, high inorganic ion content (such as chloride), significant residual metal loads and small amounts of entrained organic compounds. Historically these effluents were housed in evaporation reservoirs, however lack of space and growing water demands have led Anglo Platinum to consider treatment of these effluents. The aim of this study was to investigate whether biological wastewater treatment could produce water suitable for onsite reuse. Bench-scale activated sludge and anaerobic digestion for co-treatment of an acidic refinery waste stream with domestic wastewater were used to give preliminary data. Activated sludge showed better water treatment at lab scale in terms of removal efficiencies of ammonia (approximately 25%, cf. 20% in anaerobic digestion) and COD (70% cf. 43% in digestion) and greater robustness when biomass health was compared. Activated sludge was consequently selected for a pilot plant trial. The pilot plant was operated on-site and performed comparably with the bench-scale system, however challenges in the clarifier design led to losses of biomass and poor effluent quality (suspended solids washout). The pilot plant was unable to alter the pH of the feed, but a two week maturation period resulted in the pH increasing from 5.3 to 7.0. Tests on algal treatment as an alternative or follow-on unit operation to activated sludge showed it not to be a viable process. The activated sludge effluent was assessed for onsite reuse in flotation and it was found that there was no significant difference between its flotation performance and that of the process water currently used, indicating the effluent generated by the biological treatment system can be used successfully for flotation. Flotation is the method whereby minerals refining operations recover minerals of interest from ore through the addition of chemicals and aeration of the ore slurry. Target minerals adhere to the bubbles and can be removed from the process.

APA, Harvard, Vancouver, ISO, and other styles

36

Eloff, Estie. "Evaluation of hydrogen as energy source for biological sulphate removal in industrial wastewaters." Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/50344.

Full text

Abstract:

Thesis (MSc)--University of Stellenbosch, 2005.
ENGLISH ABSTRACT: Biological removal of sulphate from wastewater can be achieved by using a gas mixture consisting of 80% hydrogen and 20% carbon dioxide as energy and carbon sources. A novel reactor, including a venturi device for optimal hydrogen gas-liquid contact, and geotextile for immobilisation of the sulphate reducing bacterial community, was introduced. Efficient, relatively stable sulphate removal was obtained when the reactor was operated in continuous mode. The maximum sulphate removal rate obtained when the reactor was 8% packed with geotextile, was 1 g S04/(L.d) and 4 g S04/(L.d) when the reactor was 80% packed with geotextile. Kinetic batch studies showed that the highest sulphate removal rates were obtained at 29.5 °C; a pH of 7.5; initial sulphate concentration of 4000 mg/L; initial alkalinity of 1600 mg/L; cobalt concentration of 3 mg/L and when excess hydrogen gas was fed compared to what is stoichiometrically required (900 ml/min). Nickel addition showed inhibition at increased concentrations (>3 mg/L). The biofilm structure was observed on the geotextile with electron microscopy, while the viability of the biofilm was indicated with fluorescence microscopy. These observations indicated the suitability of the geotextile as a support material for biofilm formation in the sulphate reducing system. The stability of the sulphate reducing community was analysed, using the T-RFLP protocol. It was shown that the composition of the community changed after a period of 3 months, when the reactor was subjected to environmental changes. The reactor was also observed to be more efficient in terms of sulphate removal after the environmental changes, of which the temperature change from an average of 39 to 29.5 °C was the most prominent. Subsequently, it was speculated that the population shift was in favour of a more efficient system for sulphate removal. A dynamic, viable, mesophilic sulphate reducing community was therefore observed on the geotextile support, responsible for successful sulphate removal in a novel venturi-reactor. Defining optimal operating conditions, and a knowledge of biofilm structure and composition may contribute to the successful implementation of the biological sulphate removal component of the integrated chemical-biological process for the treatment of industrial wastewater, when hydrogen and carbon dioxide are supplied as the energy and carbon sources, respectively.
AFRIKAANSE OPSOMMING: Ongewenste industriële afval-water kan biologies behandel word deur 'n gasmengsel van 80% waterstof en 20% koolstofdioksied te gebruik vir sulfaat verwydering. 'n Reaktor wat 'n venturi apparaat bevat vir optimale waterstofgas-vloeistof kontak, asook geotekstiel vir die immobilisasie van die bakteriële sulfaatverwyderende gemeenskap, is bekend gestel. Effektiewe, relatief stabiele sulfaatverwydering is waargeneem sodra die reaktor op 'n kontinue basis gevoer is. Die optimale sulfaat verwyderingstempo wat bereik is as die reaktor 8% met geotekstiel gevul was, was 1 g S04/(L.d) en 4 g S04/(L.d) wanneer die reaktor 80% met geotekstiel gevul was. Kinetiese groepstudies het getoon dat die beste sulfaatverwydering bereik is by 'n gemiddelde temperatuur van 29.5 °C; pH van 7.5; aanvanklike sulfaatkonsentrasie van 4000 mg/L; aanvanklike sulfied konsentrasie van 268 mg/L; aanvanklike alkaliniteit van 1600 mg/L; kobalt konsentrasie van 3 mg/L, asook wanneer 'n oormaat waterstofgas gevoer is (900 ml/min), in vergelyking met wat stoichiometries benodig word. 'n Verhoogde byvoeging van nikkel by die voerwater (3 mg/L), het tekens van inhibisie getoon. Die biofilm struktuur is waargeneem op die geotekstiel met behulp van 'n elektronrnikroskoop, terwyl die lewensvatbaarheid van die biofilm aangedui is met behulp van fluoressensie mikroskopie. Hiermee is die bruikbaarheid van geotekstiel as 'n ondersteunings-matriks bevestig. Die stabiliteit van die sulfaatverwyderende gemeenskap is ondersoek deur die T-RFLP protokol te gebruik. Hiermee is aangedui dat die samestelling van die gemeenskap verander het na die 3 maande toets periode, toe die reaktor onderhewig was aan omgewings veranderinge. Die reaktor het ook 'n verbetering in sy sulfaatverwyderings vermoë getoon na hierdie tydperk van omgewingsveranderinge, waarvan 'n temperatuur verandering vanaf 'n gemiddeld van 39 na 29.5 °C die prominentste was. Dit is dus gespekuleer dat die populasie verskuiwing ten gunste was van 'n beter sisteem vir sulfaatverwydering. 'n Dinamiese, lewensvatbare, mesofiliese sulfaatreduserende gemeenskap, verantwoordelik vir die sulfaatverwydering in die venturi-reaktor, is dus waargeneem op die geotekstiel as 'n ondersteuningsmatriks. Met hierdie evaluasie kan die insig wat verkry is in die reaktor samestelling en die optimale kondisies vir die reaktor werking, bydra tot die suksesvolle implementasie van die biologiese komponent, in die geïntegreerde chemies-biologiese proses vir die behandeling van industriële afval water, wanneer 80% waterstof en 20% koolstofdioksied gas as energie en koolstofbron respektiewelik, gebruik word.

APA, Harvard, Vancouver, ISO, and other styles

37

Tandiyoputri, Gadis. "The effect of thermal pre-treatment and waste paper addition to biomethane potential of macroalgae Saccharina latissima." Thesis, Linnéuniversitetet, Institutionen för byggd miljö och energiteknik (BET), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-76355.

Full text

Abstract:

As a steady renewable energy technology, biogas is a viable alternative to reduce our dependency to fossil fuels and to prevent severe climate change. Biogas potential can be improved through combining different types of substrate and inoculum, as well as through substrate pre-treatments. This study aims to observe and explore the potential of macroalgae Saccharina latissima as a promising new source in renewable energy technology. The biomethane potential of macroalgae in mixture with additional substrate of mixed waste paper will be studied as a mean to improve the biogas yield. It will also compare the biomethane results of the macroalgae and the mixed substrate (macroalgae plus waste paper) exposure to non-thermal and thermal pre-treatment. In the experiment, the ratio of 3 : 1 for gr VS inoculum : gr VS substrate is used in a quantitative BMP test up to 25 days of incubation. The substrate was pre-treated mechanically (blended) into slurry and thermally through pre-heating at high temperature (130°C, 45 minutes) before digested by the inoculum. In the end of incubation period at STP (0°C and 1 atm), the highest cumulative methane yield of 260.91 Nml CH4/gr VS substrate was achieved by sample in Var – I, while the control has cumulative methane yield of 50.52 Nml CH4/gr VS. Thermally pre-treated samples resulted in lower BMP yields than the ones which were not thermally pre-treated. Through the ANOVA t-test of the methane volume and biomethane potential (BMP) yields, it is concluded that the thermal pre-treatment and waste paper addition only give little effect to biomethane production from macroalgae.

APA, Harvard, Vancouver, ISO, and other styles

38

Luby, Theresa. "Lab-scale biological wastewater treatment reactors to assess the combined effects of cold temperatures and ozonation on waste biosolids reduction." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121265.

Full text

Abstract:

The treatment and disposal of waste biosolids from activated sludge wastewater treatment plants can contribute a large portion of the total operation costs. Many technologies are being explored to address this issue, and ozonation of return activated sludge (RAS) has been shown to economically reduce waste biosolids production in Europe. However, as European winter temperatures rarely fall below 12 °C, little research has been done on biosolids reduction by ozonation at cold temperatures like during Canadian winters. A previously performed global sensitivity of a model describing ozone transformations suggested that, below 12 °C, the nitrification and other processes in a treatment plant could be less stable in the plant with RAS ozonation than without. Thus, the objective of this research was to experimentally determine the behaviour at cold temperatures of RAS ozonation for the reduction of biosolids production, and the effects of the process on treatment performances. Four 2-L sequencing batch reactors (SBRs) were designed and built, and the operation was optimized. The SBRs were fed a synthetic municipal wastewater, and operated at 0.5-day hydraulic retention times (HRTs) and 15-day solids retention times (SRTs). One SBR pair was maintained at 8 °C while the other pair was kept at room temperature (~20 °C). Within each pair, one reactor was operated as a non-ozonated control, while a portion of the suspended solids of the other was periodically ozonated such as to reach a biosolids reduction target of 40%. Analyses of chemical oxygen demand (COD), suspended solids, and ammonium concentrations were performed and tracked over a 6-month period. It was found that after an initial adaptation phase, biosolids inventory in the ozonated reactor remained similar to the control and maintained an acceptable COD conversion at both temperatures. The ammonium removal in the cold ozonated reactor did not recover once ozonation began, as it did in the warm reactor, and full nitrification was lost in both cold reactors when the nitrogen concentration was increased. A preliminary computer model of the cold SBRs was developed. The calibrated model satisfactorily predicted the solids inventory and effluent soluble COD. Therefore, while biosolids and COD conversion with ozonation can be maintained at a temperature of 8 °C, reactor nitrification performance was found to be unstable so far at that temperature, but further research is needed to fully understand this unexpected result.
Le traitement et l'élimination des biosolides produits aux usines d'épuration par boues activées peuvent contribuer à une grande partie des frais de fonctionnement. À travers le monde, de nombreuses technologies sont examinées pour résoudre ce problème. En Europe, l'ozonation des boues activées recirculées (return activated sludge [RAS] en anglais) peut réduire économiquement la production de biosolides. Cependant, les températures hivernales d'Europe tombent rarement en dessous de 12 °C, donc peu de recherches ont exploré la réduction des biosolides par ozonation à des températures froides, comme celles des hivers canadiens. Une analyse de sensibilité globale réalisée précédemment sur un modèle décrivant les transformations de l'ozone a suggéré qu'en dessous de 12 °C la nitrification et d'autres processus d'une usine d'épuration pourraient être moins stable si un système d'ozonation des RAS est installé. Ainsi, l'objectif de cette recherche était de déterminer expérimentalement le comportement à des températures froides de l'ozonation des RAS sur la réduction de production de biosolides, ainsi que l'effet de ce processus sur les performances du traitement biologique. Quatre réacteurs biologiques séquentiels (RBS) de 2 L ont été conçus et construits, et l'opération a été optimisée. Les RBS ont été alimenté par de l'eau usée municipale synthétique. Ils étaient opérés avec un temps de rétention hydraulique de 0,5 jour et un temps de rétention des solides de 15 jours. Une des paires de RBS fut maintenue à 8 °C tandis que l'autre paire fut opérée à température ambiante (~20 °C). Dans chaque paire, un des réacteurs était le réacteur contrôle (c'est-à-dire non traité à l'ozone), tandis qu'une partie des matières en suspension (MES) de l'autre réacteur était périodiquement exposée à l'ozone pour atteindre un objectif de réduction de la production de biosolides de 40%. Les analyses de la demande chimique en oxygène (DCO), des matières en suspension et des concentrations d'ammonium ont été effectuées et suivies sur une période de 6 mois. Après la phase initiale d'adaptation, l'inventaire des biosolides dans le réacteur ozoné était comparable à celui du réacteur contrôle. De plus, l'enlèvement de la DCO fut maintenue à des niveaux acceptables aux deux températures d'opération pour tous les réacteurs. Une fois que l'ozonation a commencé, l'enlèvement de l'ammonium dans le réacteur ozoné à température froide ne s'est pas rétabli à un niveau similaire à celui avant l'ozonation malgré que le réacteur à température ambiante ait bien réussi le rétablissement. Cependant, la nitrification complète a été perdue dans les deux réacteurs à température froide lorsque la concentration d'azote a augmenté. Un modèle informatique préliminaire des RBS à température froide a été calibré. Le modèle calibré a pu prédire la quantité de matières solides et la concentration de DCO soluble dans l'effluent, avec une marge d'erreur acceptable. Par conséquent, tandis que l'inventaire des biosolides et la conversion de DCO avec l'ozonation peuvent être maintenus à une température de 8 °C, les performances de nitrification du réacteur étaient instables à cette température. Des recherches supplémentaires sont nécessaires pour comprendre pleinement ce résultat inattendu.

APA, Harvard, Vancouver, ISO, and other styles

39

Carley, Brian Neal. "The effect of excess carbon in the anoxic basin of a biological pre-denitrification system for the treatment of landfill leachate." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28371.

Full text

Abstract:

This study investigated the effect of excess carbon loading in the anoxic reactor on the nitrogen removal capacity of a biological pre-denitrification system for the treatment of a high ammonia leachate. The influent leachate was low in degradable organic carbon, thus an external carbon source was needed for denitrification requirements. Four different carbon sources were studied: methanol, glucose, acetate, and a waste brewer's yeast. The carbon loading was increased over the duration of the experimental period. The COD:NOx added to the anoxic reactor reached more than three times the carbon loading required to just achieve complete denitrification. All four carbon sources were found to support denitrification, but the glucose system showed erratic behaviour and ultimately failed after reaching a CODrNOx loading of about 23:1. The system using acetate appeared to require the least amount of COD:NOx (5.9:1) for complete denitrification, followed closely by methanol (6.2:1), then the yeast waste (8.5:1), and finally by glucose (9:1). Carbon breakthrough, the bleeding of carbon from the anoxic reactor into the aerobic reactor, was observed to occur just after complete denitrification was reached. The excess carbon did not appear to have any effect on denitrification, except in the case of the glucose system. The unit nitrification was found to decrease as the CODrNOx was increased, even though the ammonia removal remained at 100%. The decrease in nitrification, with respect to the COD:NOx, was most pronounced in the system that used methanol, and about equal in the other three systems. The cause of the decrease in nitrification is suspected to be due to increased ammonia assimilation by the heterotrophs rather than an inhibition of the nitrifiers. Nitrification ceased in the glucose system, but was restored within 12 days after the glucose addition was halted. The cause of the failure of the nitrogen removal process in the glucose system was not determined. Nitrite accumulation was observed in all the systems except the methanol system. The yeast waste system had nitrite accumulation in the aerobic reactor at C0D:N0x loadings over 25:1. Free ammonia inhibition of Nitrobacter is suspected to be the cause of aerobic nitrite buildup. The glucose and acetate systems had nitrite buildup in the anoxic reactor until complete denitrification was achieved. Facultative anaerobic bacteria are suspected of causing this nitrite accumulation. This theory was supported by observations in the glucose system, such as low anoxic pH; this may have been due to volatile fatty acids produced from fermentation.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

APA, Harvard, Vancouver, ISO, and other styles

40

Stoll, Anita. "Bioaccumulation of heavy metals by the yeast S. cerevisiae and the bioremediation of industrial waste water." Thesis, Rhodes University, 1997. http://hdl.handle.net/10962/d1004075.

Full text

Abstract:

Water is an essential element in all aspects of life and is vital for both domestic and industrial purposes regarding both the quality and quantity thereof. Similar to many other drought stricken countries, South Africa requires water for the socio-economic growth of the country, yet is faced with the problem of maintaining the quality of its drinking water as well as protecting the dwindling supplies. In an attempt to prevent the deterioration of South African water supplies the treatment, purification and recycling of industrial and mining waste water has recently become of prime importance. Many industrial and mining waste waters contain heavy metals in toxic quantities. The conventional processes that have been used till recently to address this problem, are often expensive or contain chemical agents which compound the environmental problem. As an alternative biological methods of metal accumulation appear to offer an economic and efficient alternative to these methods. An advantage to the South African scenario is the commercial production of the yeast, S. cerevisiae as a readily inexpensive by-product from some fermentation industries, Yeast cells, and in particular S. cerevisiae have proven to be capable of accumulating heavy metals, and therefore exhibit potential application in the bioremediation of waste water. The aim of this project was twofold. The initial part of this work attempted to define the mechanisms of metal accumulation by the yeast cells and cellular components. The information obtained from these initial studies provided a data base required for the development of a bioremediation system. Initial contact with the metal ions occurs at the wall interface of the yeast cell. Metal accumulation appears to be a function of all the cell wall components. The isolated cell wall components are better metal chelators then the intact cell walls. An apparent affinity series of mannan > chitin> glucan > intact cell walls exists. However, these components differ in their affinities for metal ions. Storage of metal ions within the cell occurs predominantly in the vacuole. The present study concluded that metal accumulation by the vacuole could be related to size. Metal accumulation occurred in the order of Cu2+ > Co2+ > Cd2+ with a corresponding decrease in atomic radii of Cd2+ > C02+ > Cu2+. Vacuolar ion deposition occurs at an early stage during the internalization of metal ions within the yeast cells. At the onset of vacuolar saturation, depositions of metal ions as granules within the cytosol occurs. In the presence of heavy metal cations viable yeast cells can be shown to exhibit two types of cellular responses. Uptake of Cu2+ and Cd2+ causes the loss of intracellular physiological cations from within the yeast cell. In comparison, uptake of Co2+ into the cell does not have this effect. All three heavy metal cations initiate plasma cell membrane permeability, thus the Cu2+ and Cd2+ induced loss of the intracellular cations, occurs. ~ a result of ion-exchange mechanisms and not due to cation leakage brought about by membrane permeabilization. Uptake of heavy metals by viable yeasts appears to be generally non-selective though the amount of metals accumulated are largely affected by the ratio of ambient metal concentration to biomass quantity. In addition, the energy dependent nature of internalization necessitates the availability of an external energy source for metal uptake by viable yeast cells. For these reasons metal removal from industrial waste water was investigated using non-viable biomass. By immobilizing the yeast cells additional mechanical integrity and stability was conferred apon the biomass. The three types of biomass preparations developed in this study, viz. polyvinyl alcohol (PV A) Na-alginate, PV A Na-orthophosphate and alkali treated polyethylenimine (PEI):glutaraldehyde (GA) biomass pellets, all fulfilled the necessary physical requirements. However, the superior metal accumulating properties of the PEI:GA biomass determined its selection as a biosorbent for bioremediation purposes. Biosorption of heavy metals by PEI:GA biomass is of a competitive nature, with the amount of metal accumulated influenced by the availability of the metal ions. This availability is largely determined by the solution pH. At low pH values the affinity of the biomass for metals decreases, whilst enhanced metal biosorption occurs at higher pHs, ego pH 4.5 - 6.0. PEI:GA biomass pellets can be implemented -as a biosorbent for the bi9remediaiton of high concentration, low-volume metal containing industrial waste. Several options regarding the bioremediation system are available. Depending on the concentration of the metals in the effluent, the bioremediation process can either be used independently or as part of a biphasic remediation system for the treatment of waste water. Initial phase chemical modification may be required, whilst two types of biological systems can be implemented as 'part of the second phase. The PEI:GA biomass can either be contained within continuous-flow fixed bed tanks or continuous-flow stirred bioreactor tanks. Due to the simplicity of the process and the ease with which scale-up is facilitated, the second type of system shows greater application potential for the treatment of this type of industrial waste water than the fixed-bed systems.

APA, Harvard, Vancouver, ISO, and other styles

41

Baccar, Ep Yangui Rim. "Removal of water pollutants by adsorption on activated carbon prepared from olive-waste cakes and by biological treatment using ligninolytic fungi." Doctoral thesis, Universitat Autònoma de Barcelona, 2013. http://hdl.handle.net/10803/131275.

Full text

Abstract:

Se utilizan diferentes procesos para el tratamiento de las aguas residuales. Sin embargo, estas tecnologías son ineficaces, generan productos secundarios o son demasiado caras. El objetivo principal de esta tesis es la eliminación de diversos contaminantes del agua, incluyendo metales, tintes y productos farmacéuticos mediante dos tecnologías. La primera consiste en un tratamiento físico-químico de adsorción sobre carbón activo preparado a partir de un resido de la industria agroalimentaria. El segundo se trata de un tratamiento biológico con hongos. En cuanto a la adsorción sobre carbón activo, en una primera etapa se consideran aspectos tales como la preparación del adsorbente, su caracterización y el estudio del impacto ambiental asociado a su producción. Para la preparación de carbón activo se realiza la activación química a partir de orujo de oliva, utilizando ácido fosfórico como agente deshidratante. Se varían los parámetros principales del proceso para optimizar las condiciones de la activación. El carbón activo preparado, se caracteriza teniendo en cuenta sus propiedades de adsorción, su estructura química y su morfología. Los resultados muestran que el adsorbente más eficaz es el que se obtiene bajo las siguientes condiciones: una concentración igual a 60% de H3PO4, una relación de impregnación de 1,75, y una temperatura de pirolisis de 450°C. El adsorbente preparado en estas condiciones presenta buenas características en comparación con los que se encuentran en la literatura. Para minimizar el impacto ambiental, ciertas modificaciones podrían incorporarse en el proceso de preparación del adsorbente tales como la recuperación del gas derivado de la etapa de pirolisis y su utilización como fuente de energía, y la recuperación de ácido fosfórico después de lavar el carbón activado. Después de establecer las condiciones óptimas se evalúa la eficiencia del carbón activo para la eliminación de los contaminantes inorgánicos y orgánicos. Para los metales, cogiendo Cu2 + como un modelo, los ensayos de adsorción en columna muestran la alta capacidad del carbón activo para reducir KMnO4 en óxido insoluble de manganeso (MnO2) que impregna la superficie del adsorbente, cuya presencia mejora significativamente los resultados de la adsorción de Cu2+ sobre el carbón activo. En cuanto a los contaminantes orgánicos, el estudio muestra la eficacia del carbón activado para eliminar colorantes de los efluentes sintéticos y reales y productos farmacéuticos de soluciones de compuestos puros y formando parte de una mezcla de fármacos. En la mayoría de los casos los modelos de Langmuir y pseudo-primero orden presentan el mejor ajuste para la isoterma y la cinética, respectivamente. La temperatura afecta la adsorción de colorantes, sin embargo, la variación de pH no tiene ninguna influencia. Al contrario que en la adsorción de los fármacos. En cuanto al proceso biológico adaptado, se ha comprobado el potencial de tres hongos ligninolíticos (Trametes versicolor, Ganoderma lucidum y Irpex lacteus) para la decoloración de un colorante de la industria de curtidos. Los resultados indican que Trametes versicolor es la mejor cepa tanto en términos de extensión y rapidez en la decoloración. Tanto en procesos en discontinuo como en discontinuos repetidos en un reactor fluidizado por pulsos de aire y con reuso de biomasa muestra que la capacidad de decoloración del hongo es del 86-89% y no disminuye durante los discontinuos repetidos a pesar de la baja actividad enzimática detectada. Se ha evidenciado que la lacasa es una enzima involucrada en la biodegradación y que el fenómeno de adsorción que ocurre en la biomasa fúngica. Finalmente, la combinación del tratamiento mediante hongos y la adsorción en adsorbentes de bajo coste puede ser una estrategia adecuada para depurar efluentes complejos.
Different processes are used for the treatment of wastewaters. However, they are either frequently ineffective, or they generate secondary products or worse, they are too expensive. The main objective of this dissertation is the removal of various contaminants in water including metals, dyes and pharmaceuticals products via two environmentally- friendly technologies. The first consists in a physico-chemical treatment- by adsorption on activated carbon prepared from olive-waste cakes. The second is about a biological treatment using white-rot fungi. First, the adsorbent preparation, its characterization and the study of the environmental impact associated with its production are considered. Chemical activation of the feedstock olive-waste cakes, using phosphoric acid as dehydrating agent, is adopted for activated carbon preparation and main process parameters (such as acid concentration, impregnation ratio, temperature of pyrolysis step) are varied to optimize the best conditions. The activated carbon prepared under the optimal conditions is then fully characterized considering its adsorption properties as well as its chemical structure and morphology. The results show that the most efficient adsorbent is that obtained under the following optimal conditions: an acid concentration equal to 60% H3PO4, an impregnation ratio of 1.75, and a pyrolysis temperature of 450 °C. The adsorption characteristics of the adsorbent prepared under such conditions presents good characteristics compared with the previous reports for activated carbon in the literature. To minimize the environmental impact, certain modifications could be incorporated in the process of adsorbent preparation such as recovery of the gas derived from the pyrolysis step, its reuse as an energy source, and the recovery of phosphoric acid after activated carbon washing. After establishing the optimal conditions, the efficiency of the optimal activated carbon for the removal of inorganic and organic pollutants is then evaluated. For heavy metals, considering the adsorption of Cu2+ ions as a model, column adsorption tests show the high capacity of the activated carbon to reduce KMnO4 into insoluble manganese (IV) oxide (MnO2) which impregnated the sorbent surface. The results also indicate that the adsorption of Cu2+ can be significantly improved by the presence of MnO2 fixed on activated carbon. Concerning the organic pollutants, the study shows the effectiveness of the activated carbon to remove dyes from individual and real effluents and pharmaceutical products from single and mixture solutions. Many models are used to understand the adsorption behavior and in the most cases Langmuir and pseudo-second order models present the best fit for the isotherm and kinetics, respectively. Temperature is found to affect the adsorption of dyes, however, the pH variation has no influence. The opposite case is found for drugs adsorption. Regarding the biological process adapted, the potential of three white-rot fungi (WRF) (Trametes versicolor, Ganoderma lucidum and Irpex lacteus) to decolorize the commercial tannery dye − Black Dycem – is investigated in solid and liquid media. The results indicate that Trametes versicolor is the best strain both in terms of extent and rapidity of decolorization. The experiment, performed in single and repeated batches in an air-pulsed bioreactor with biomass reuse of the fungus Trametes versicolor, shows that the decolorization capability of the fungus does not decrease during the repeated batches and the fungus is able to remove 86−89% of the dye despite the low enzyme activity detected. The results also show that the biodegradation mechanism plays a noticeable role in the decolorization process of the dye by means of laccase activity in addition to the adsorption phenomenon occurring on the fungal surface. Finally a combination of fungal treatment and adsorption on low cost adsorbents could be a suitable strategy to remove pollutants from complex effluents.

APA, Harvard, Vancouver, ISO, and other styles

42

Dong, Xiao. "Techno-Economic Analysis of a Cost-Effective Treatment of Flowback and Produced Waters via an Integrated Precipitative Supercritical Process." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1429533649.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Blomgren, My. "The connection between the issue of food waste and its collection for biogas : A case study in the municipality of Stockholm." Thesis, Stockholms universitet, Kulturgeografiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-90444.

Full text

Abstract:

Reduction is the best way of handling the issue of food waste, however, considering the difficulties of achieving reduction, a collection of waste for a potential decrease was established. The thesis consist of an examination between two subjects, the issue of food waste and the waste management system of collecting food waste to produce biogas, where the main focus is upon the municipality of Stockholm. The purpose of the study was to analyze the issue of food waste and connect it to the process of collecting food waste to produce biogas, and examine the potential benefits and conflicts between these two topics. The aim was also to investigate the process possibilities and functionality, and how the procedure is operating in the municipality of Stockholm. Besides a litterature study, four interviews were conducted with respondents from authorities and the municipality. The results show that the process of collecting food waste to produce biogas is a great procedure. It is a good alternative for the environment and generates to a substitute towards fossil fuel. However, whether the process is a benefit for the issue of food waste seems to be rejected. There are also difficulties of apprehending the connection between the two subjects, since they are seen as topics that lie collaterally to each other. In the municipality of Stockholm, the process function within the section of restaurants, however, it is not that fortunate within households. The factors of simplicity, profitability and trust are the main features threatening the success of the process of collecting food waste to produce biogas. One may presume that the goal/requirement firsthand is to focus upon reduction of food waste. However, there seems to be a shift from consuming less (reduce the waste) to consuming differently (reuse the waste) nowadays, hence the process of collecting food waste to produce biogas is central.

APA, Harvard, Vancouver, ISO, and other styles

44

Duval, Alexandra M. "Valorization of Carrot Processing Waste." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2155.

Full text

Abstract:

Commercial carrot processors produce up to 175,000 tons of carrot waste annually. Carrot Mash (CM) is the term referring to the waste by-product of peeled baby carrot processing. Transportation of carrot processing waste is expensive due to its high- water content (approx. 83-95%). High in bioactive compounds (carotenoids) and dietary fibers, it is expected that its conversion into a value-added by-product is of interest to the carrot processing industry. Hemicellulose-rich plant materials have proven to be a source of oligosaccharides, which are known for their beneficial prebiotic activity. The objectives of this research were to: 1) determine the effect of mechanical treatments on the extraction of water and bioactive compounds and evaluate the functional properties of carrot mash; 2) incorporate dried carrot mash into a beef patty and evaluate changes in pH, color, cooking yield, and texture; 3) apply an enzymatic treatment to carrot mash to promote the conversion of polysaccharides to oligosaccharides for prebiotic benefits. Mechanical separation of liquid and solid fractions by way of expeller pressing was efficient in extracting liquid while simultaneously increasing total solids by nearly 200%, the extraction of carotenoids by 1000%, and polyphenol content by nearly 97%. Mechanical treatments increased the fat binding capacity on average by 183% compared to untreated mash. The addition of unpressed carrot mash or expeller pressed carrot mash increased the cooking yield of a beef patty by 3-13% without significantly changing its textural properties. Enzymatically treating the carrot mash significantly increased the concentration of oligosaccharides up to 2.3%. These results suggest that carrot processing wastes can be physically and enzymatically modified and have an immense potential to be utilized as a functional ingredient in human food rather than being landfilled, composted or used as animal feed.

APA, Harvard, Vancouver, ISO, and other styles

45

Fortin, Nathalie. "Molecular characterization of dechlorination potential in kraft pulp mill effluent treatment systems." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27317.

Full text

Abstract:

Many low molecular weight chlorinated organic compounds produced by the pulp and paper industry during kraft bleaching of the wood pulp are toxic. Mass balance studies suggest that mineralization of chlorinated organics is occurring in pulp and paper mill wastewater treatment systems. To understand the nature of dechlorination activity, molecular tools such as oligonucleotide primers and corresponding DNA probes were developed to monitor the presence of microorganisms possessing key genes (dehalogenases) responsible for the degradation of chloroaliphatic organics in kraft pulp mill effluent treatment systems. Oligonucleotide primers designed from the coding sequence of known dehalogenases and a methane monooxygenase gene, which is known to catalyze dehalogenation reactions, were used for polymerase chain reaction (PCR) analysis, using genomic DNA extracted from dehalogenating bacterial isolates and total community DNA extracted from water and sediments of lagoon treatment systems. PCR amplification with dhlB oligonucleotide primers, designed from the haloacid dehalogenase of Xanthobacter autotrophicus, revealed the presence of dehalogenase genes in both aerated lagoons and stabilization basins. Similar results were obtained with mmoX primers designed from the methane monooxygenase gene of Methylococcus capsulatus. DNA sequence analysis of several PCR fragments showed significant similarity to known dehalogenase genes. The molecular tools developed in this study revealed the presence of different types of microorganisms with dechlorination potential in the microbial community of pulp mill effluents.

APA, Harvard, Vancouver, ISO, and other styles

46

Tandiyoputri, Gadis. "The effect of thermal pre-treatment and waste paper addition to biomethane potential of macro algae Saccharina lattissima." Thesis, Linnéuniversitetet, Institutionen för byggd miljö och energiteknik (BET), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-76383.

Full text

Abstract:

As a steady renewable energy technology, biogas is a viable alternative to reduce our dependency to fossil fuels and to prevent severe climate change. Biogas potential can be improved through combining different types of substrate and inoculum, as well as through substrate pre-treatments. This study aims to observe and explore the potential of macroalgae Saccharina latissima as a promising new source in renewable energy technology. The biomethane potential of macroalgae in mixture with additional substrate of mixed waste paper will be studied as a mean to improve the biogas yield. It will also compare the biomethane results of the macroalgae and the mixed substrate (macroalgae plus waste paper) exposure to non-thermal and thermal pre-treatment. In the experiment, the ratio of 3 : 1 for gr VS inoculum : gr VS substrate is used in a quantitative BMP test up to 25 days of incubation. The substrate was pre-treated mechanically (blended) into slurry and thermally through pre-heating at high temperature (130°C, 45 minutes) before digested by the inoculum. In the end of incubation period at STP (0°C and 1 atm), the highest cumulative methane yield of 260.91 Nml CH4/gr VS substrate was achieved by sample in Var – I, while the control has cumulative methane yield of 50.52 Nml CH4/gr VS. Thermally pre-treated samples resulted in lower BMP yields than the ones which were not thermally pre-treated. Through the ANOVA t-test of the methane volume and biomethane potential (BMP) yields, it is concluded that the thermal pre-treatment and waste paper addition only give little effect to biomethane production from macroalgae.

APA, Harvard, Vancouver, ISO, and other styles

47

NOGUEIRA, NETO ANTONIO C. "Avaliacao de teoxidade aguda e cronica em aguas do Rio Jundiai e em afluentes e efluentes da ETE Novo Horizonte, Jundiai, Sao Paulo." reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9450.

Full text

Abstract:

Made available in DSpace on 2014-10-09T12:26:54Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:00:52Z (GMT). No. of bitstreams: 0
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

APA, Harvard, Vancouver, ISO, and other styles

48

Jackson-Moss, Clive Alan. "An investigation into the use of anaerobic digestion for the treatment of tannery wastewaters." Thesis, Rhodes University, 1991. http://hdl.handle.net/10962/d1004120.

Full text

Abstract:

The anaerobic digestion of tannery wastewaters was investigated with a view to using this form of treatment in the tanning industry. As these wastewaters are extremely complex and contain high concentrations of both inorganic and organic compounds, the effect of these individual compounds on the anaerobic digestion process was investigated in detail, in order to ascertain the fate of these compounds during the digestion process. The experiments comprising the initial toxicity study were carried out as adaptation experiments using a synthetic wastewater. It was found that the heavy metals such as chrome, aluminium and iron precipitated and accumulated in the sludge bed of the digesters . The soluble ions such as sodium and chloride were not retained and passed through the digesters. Approximately 20 % of the calcium ions were removed through precipitation, with the remainder being present in the digester effluent . Under the anaerobic conditions, ammonification of the organic nitrogen occurred, and influent sulphates were reduced to sulphides . These sulphides were present as either H2S, HS or insoluble sulphides. As these compounds under investigation on caused no inhibition of the anaerobic digestion process at the concentrations found in tannery wastewaters, the anaerobic treatment of these wastewaters appeared to be possible, provided the bacteria were given sufficient time to adapt to the potentially toxic compounds. However, despite the findings of the synthetic study, the successful anaerobic digestion of the tannery effluents could not be achieved. Although the use of acid was found to be essential in order to control the digester pH in the optimum range, the metabolism of the methanogenic bacteria was inhibited by the presence or absence of unknown compounds. Neither the addition of essential trace nutrients, nor the prevention of the competition between the methanogens and the sulphate-reducing bacteria were able to reverse this inhibition. As tannery effluents contain very low concentrations of phosphorous, it is possible that the methanogens were inhibited by a lack of phosphorous, which is essential during methanogenesis. In contrast to the results obtained from the effluent experiments, the anaerobic digestion of tannery sludge was found to be possible. Of the organic solids present in the sludge, 60 % were degraded and converted into biogas, which had a methane content greater than 70 %. The degradation of the organic solids ensured that COD and PV reductions of greater than 90 % were achieved, and the fate of the compounds in the digesters were in agreement with the findings of the v synthetic study. Efforts to improve the efficiency of the digestion process through the addition of trace nutrients and the use of a two-stage process were only successful in bringing about a minor improvement in digester performance. The overall results of this investigation show, therefore, that although the anaerobic treatment of the tannery effluent was not achieved, the successful anaerobic digestion of tannery sludge is possible at low loading rates. As many difficulties still need to be solved, a great deal of further research is necessary if anaerobic digestion is to be used on an industrial scale for the treatment and disposal of tannery wastewaters.

APA, Harvard, Vancouver, ISO, and other styles

49

McLachlan, Tania. "Integration of a combined UASB-ozonation treatment system for cellar effluent degradation." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/53749.

Full text

Abstract:

Thesis (MSc Food Sc)--Stellenbosch University, 2004.
ENGLISH ABSTRACT: The wine industry significantly contributes to South Africa's water demand and subsequent pollution of the limited resource. Wastewater is produced throughout the year with an increase in volume and organic load during the vintage season. Anaerobic digestion (AD), specifically the upflow anaerobic sludge bed (UASB) technology has been shown to be feasible in the treatment of cellar wastewater. However, the legal standard for chemical oxygen demand (COD) for disposal in a natural water resource (75 rnq.L") is often not met. The aim of the study was to conduct a laboratory-scale investigation into the feasibility of combining pre- and post-ozonation processes with AD in order to achieve a final COD closer to the legal disposal limit. While acclimatising an UASB bioreactor containing mixed anaerobic granules to a cellar wastewater with a pH set at 8.0, stable-state conditions were not reached. Sucrose additions to the substrate, increased substrate loads, heattreatment of the substrate and an addition of isolated cellar effluent bacteria to facilitate degradation prior to AD, were all unsuccessful in maintaining stable-state in terms of COD removal efficiency. Once the substrate pH was re-set to 7.5, the reactor stabilised. The lowest efficient operational pH was found to be 5.73 resulting in a COD removal of 88% at a substrate COD < 5 000 rnq.L". At a substrate pH of 6.0, the lowest efficient operational hydraulic retention time (HRT) and corresponding organic loading rate (OLR) were 19.7 hand 9.75 kg COD.m-3d-1 , respectively, with the COD removal being maintained around 84%. The reactor effluent still had a final COD of 1280 rnq.L", which was well above the legal South African limit. Dominant bacteria were isolated from raw cellar wastewater and identified as Acinetobacter haemolyticus, Burkholderia cepacia and Cryseomonas luteola. In order to investigate the possibility that ozonation improved biodegradability, the growth of the isolates at 35°C was monitored over 24 h in sterile ozonated and non-ozonated substrates from the vintage and non-vintage seasons. All the isolates increased by at least 1.5 log cycles in the control substrates from both seasons. Ozonation of the wastewater batches for 10 min at a rate of 73 rnq.L" led to slightly increased growth of the inoculants in the substrate batch from the vintage season. For the substrates from the non-vintage season, ozonation had an inhibitory effect on the bacterial growth. A 5 min ozonation treatment at a concentration of 73 rnq.L" was found to be optimal for both a pre- and post-treatment to UASB-treatment of cellar wastewater. Both UASB treatment and ozonation were effective in reducing the COD by 85% and 20%, respectively. The COD reduction was improved to 88% when UASB treatment was combined with post-ozonation. The total reduction in total suspended solids (TSS) for the combined process was 97%, compared to 80% for UASB and 73% for an ozone treatment alone. The reduction for volatile suspended solids (VSS) was 98% compared to 81% for UASB and 73% for the ozone treatment alone. The total reduction when using a pre-ozonation UASB treatment combination was an average of 86% for COD. The TSS and VSS were both reduced by 95%. Biogas production increased from 1.4 L.d-1 to 3.8 L.d-1 when an ozonated wastewater was used as substrate. When the UASB treatment was combined with both a pre- and post-ozonation treatment process, the COD was reduced by 89% while TSS and VSS were both reduced by 99%. This study showed that pre- and post-ozonation treatment processes could successfully be utilised to improve UASB treatment of cellar wastewater. Although the legal limits for discarding into a natural resource were not met, significant progress was made in reducing COD levels. Cellar wastewaters do however, vary according to season and the wastewater composition could affect the efficiency of a pre-ozonation process.
AFRIKAANSE OPSOMMING: Die wynindustrie maak "n beduidende bydrae tot die eise wat aan Suid-Afrika se waterbronne gestel word en gevolglik die besoedeling van die beperkte hulpbron. Afloopwater, wat in volume en organiese lading gedurende die parstyd toeneem, word reg deur die jaar opgelewer. Anaërobiese vertering (AV), spesifiek die "Upflow anaerobic sludge blanket" (UASB) tegnologie, is alreeds suksesvol gebruik om kelderafloop te behandel. Die wetlike vereiste vir chemiese suurstof behoefte (CSB) vir storting in "n natuurlike hulpbron (75 rnq.L"), word egter dikwels nie bereik nie. Die doel van die studie was om in "n laboratorium-skaal ondersoek AV te kombineer met voor- en na-osoneringsprossesse, om sodoende te poog om "n CSB nader aan die wetlike standaard te verkry. Terwyl"n UASB bioreaktor wat gemengde anaerobiese granules bevat het, geakklimatiseer is tot kelderafloop met "n pH gestel tot 8.0, kon stabiele toestande nie bereik word nie. Die byvoeging van sukrose tot die substraat, verhoogde substraatladings, hitte-behandeling van die substraat en die byvoeging van geïsoleerde kelderafloop bakterië om substraatafbraak voor AV aan te help, was onsuksesvol om stabiliteit in terme van CSB-verwydering, te handhaaf. "n Verstelling van die substraat pH na 7.5, het gelei tot reaktorstabiliteit. By die laagste doeltreffende bedryfs-pH van 5.73 en substraat CSB < 5 000 rnq.L", was die CSB-verwydering 88%. By "n substraat pH van 6.0 was die laagste doeltreffende bedryfs-hidroliese retensie tyd en -organiese ladingstempo 19.7 h en 9.75 kg CSB.m-3d-1, onderskeidelik, terwyl die CSB verwydering rondom 84% gehandhaaf is. Die CSB van die reaktoruitvloesel van 1 280 rnq.L", was steeds ver bo die wetlike vereiste. Dominante bakterië is uit kelderafloop geïsoleer en as Acinetobacter haemolyticus, Burkholderia cepacia en Cryseomonas luteola, geïdentifiseer. Die moontlikheid dat osonering bioafbreekbaarheid bevorder, is ondersoek deur die groei van die isolate by 35°C oor 24 h in steriele geësoneerde en ongeësoneerde substrate te monitor. Die substrate is berei vanaf kelderafloop wat in die parsseisoen sowel as die nie-parsseisoen versamel is. AI die isolate het met ten minste 1.5 log siklusse in die kontrole substrate van beide seisoene, vermeerder. Vir die kelderafloop wat in die parsseisoen versamel is, het osonering vir 10 min teen 73 rnq.L" gelei tot effens verbeterde groei van die innokulante. Osonering het 'n onderdrukkende effek op die groei van bakterië in die afloopwater versamel in die nie-parsseisoen, gehad. Osonering vir 5 min teen 'n konsentrasie van 73 rnq.L" is as optimum vir beide voor- en na-osoneringsbehandeling tot UASB-behandeling van die kelderafloop, gevind. UASB-behandeling en osonering het die CSB met 85 en 20% onderskeidelik, verminder. Die vermindering kon tot 88% verhoog word wanneer UASB-behandeling met na-osonering gekombineer is. Die vermindering in totale gesuspendeerde vastestowwe (TGV) vir die gekombineerde proses was 97%, in vergelyking met 80% vir UASB- en 73% vir osoonbehandeling alleen. Die vermindering in vlugtige gesuspendeerde vastestowwe (VGV) was 98% in vergelyking met 81% vir UASB- en 73% vir osoonbehandeling alleen. Die totale CSB verwydering vir 'n voor-osonerings UASB kombinasie was gemiddeld 86%. Die TGV en VGV is beide met 95% verminder. Biogasproduksie het ook vermeerder vanaf 1.4 L.d-1 tot 3.8 L.d-1 toe geosoneerde afloopwater as substraat gebruik is. Die kombinasie van UASB-behandeling met voor-osonering, sowel as na-osonering het gelei tot 'n CSB-verwydering van 89% terwyl TGV en VGV beide met 99% verminder is. Hierdie studie het getoon dat voor- en na-osonering suksesvol gebruik kan word om UASB-behandeling van kelderafloop te verbeter. Hoewel wetlike vereistes vir storting in 'n natuurlike hulpbron nie bereik is nie, is beduidende vordering gemaak in die verlaging van CSB-vlakke. Die verskil in die samestelling van kelderafloop gedurende die onderskeie seisoene, kan egter die doeltreffendheid van die voor-osoneringsproses beïnvloed.

APA, Harvard, Vancouver, ISO, and other styles

50

Balsvik, Jonathan. "Life cycle assessment of industrialized lithium-ion battery recycling : Mechanical and hydrometallurgical treatment from an ex-ante perspective." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-296953.

Full text

Abstract:

As the use of lithium-ion batteries exponentially increases through demand for electric vehicles and energy storage systems, so will the need for end-of-life treatment subsequently increase. Recycling the valuable materials from batteries in an efficient and extensive fashion could decrease the environmental impacts of batteries. Northvolt AB is a Swedish battery manufacturer currently constructing a Gigafactory in Skellefteå and is furthermore developing a recycling process, focused on hydrometallurgy, with full-scale recycling operations a couple of years away. In order to assess the environmental hotspots of the process, with a focus on greenhouse gas emissions, a life cycle assessment was conducted with data from Northvolt AB. This data was based on learnings from a pilot plant currently under operation but scaled up to industrial level for an ex-ante type of assessment. The industrial operations at Skellefteå represented +95% of the climate change impact, the remainder arising from a European collection point. The most significant impact driver was waste management (56,5% of the climate change impact category), specifically incineration of recovered materials and residuals. The results indicate that harnessing renewable energy in both the direct operations and the supply chain is of high importance. Chemicals (27%) and electricity (7%) had extensively smaller emissions thanks to the harnessing of renewable energy in both direct operations and the supply chain, compared to electricity mixes with large shares of fossil fuels. Furthermore, large variability was found in impacts of recovered materials depending on the chosen allocation method. The benefit of the Revolt process is likely to be affected by ongoing research projects to recycle and upgrade materials that are currently sent to incineration. For an as high environmental efficiency as possible, it is important that the process make as much use of all the recovered materials as possible, find efficient waste treatment processes, and continue to source from production using as electricity mixes with high shares of renewable energy.
Givet att användningen av litium-jon batterier ökar exponentiellt, drivet av efterfrågan på elfordon och energilagringssystem, så kommer behovet av att avfallshantera utgående batterier att öka. Att återvinna värdefulla material från batterier på ett effektivt och omfattande sätt skulle kunna minska batteriernas miljöpåverkan sett över hela dess livscykel. Northvolt AB är en svensk batteritillverkare som bygger en fabrik i Skellefteå och parallellt utvecklar en återvinningsprocess med fokus på hydrometallurgi, med fullskalig återvinning planerad. För att utvärdera vilka aspekter av processen som driver dess miljöpåverkan, med fokus på utsläpp av växthusgaser, gjordes en livscykelanalys med data från Northvolt AB. Datainventeringen baserades på lärdomar från en pilotanläggning som för närvarande är under drift, men skalades upp till industriell nivå för en förhandsbedömning. Industriverksamheten i Skellefteå stod för +95% av klimatpåverkan, resten härrör från en europeisk insamlingsplats av utgående batterier. Den viktigaste bidragsfaktorn för klimatutsläpp var avfallshantering (56,5 % av utsläppen), särskilt förbränning av återhämtade material och restprodukter. Resultaten visar att det är av stor betydelse att utnyttja förnybar energi i både den direkta verksamheten och leverantörskedjan. Kategorierna kemikalier (27%) och el (7 %) hade betydligt lägre utsläpp tack vare att förnybar energi utnyttjades, i jämförelse med nationella elmixer med större andelar fossila bränslen. Vidare konstaterades stor variation i resultatet av miljöpåverkan på återvunnet material beroende på vald allokeringsmetod. Fördelarna med Revoltprocessen kommer sannolikt att påverkas av pågående forskningsprojekt för att återvinna och uppgradera material som för närvarande skickas till förbränning. För minskade klimatutsläpp är det viktigt att processen i så stor utsträckning som möjligt materiellt återvinner alla utgående material, hittar effektiva avfallshanteringsprocesser och fortsätter att etablera en leverantörskedja som producerar med stora andelar förnybar energi. Utöver att utvärderingen gjordes med preliminära data resonerades avfallshanteringen vara den enskilt största källan till osäkerhet. Framtida livscykelanalyser skulle dra nytta av uppmätt data när den industriella anläggningen är operationell, samt vidga analysen med mer utförlig datainhämtning från relevanta avfallsprocesser och återvinningstekniker.

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'Mechanical and biological treatment of waste'

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