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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Evaluation of Composting of Municipal Solid Waste

Stebbins, J. Ryan 01 May 2014 (has links)
A field-scale commercial compost study was conducted to evaluate the impact of the Bio-Environmental Resource Recovery International (BERRI) Microbial Assisted Regeneration System (MARS) process, specifically its proprietary microbial inocula, on compost production of various agricultural waste and municipal solid waste (MSW) mixtures. Treated and control windrows were constructed to compare the MARS inoculum by quantity and quality of compost produced, organic stabilization time, and individual component sorting (i.e., green waste, wood, agriculture waste, food waste, MSW, C&D debris, and tires). Specific VOC and SVOC compounds, as well as a common pesticide, carbaryl, were added specifically for this study and the compounds were analyzed for degradation rates. The quality of the compost product was assessed using a method developed for classifying municipal solid waste compost. The quantity of compost produced was determined by screening the entire volumes of each pile to determine a gross production of compost for each pile. Compost samples were analyzed by headspace gas chromatography mass spectrometry for VOCs, methylene chloride extraction and gas chromatography mass spectrometry for SVOCs, and methanol extraction and high-performance liquid chromatography mass spectrometry for carbaryl. The quality of compost was found to have a very low nutrient capacity making the compost only useable as a soil conditioner. Treated piles showed a significantly larger amount of compost production and a decreased time for organic stabilization. No significant degradation of plastics or woods components was observed in any of the treatments used in the study.
32

Design and analysis of static windrow piles for in-house broiler litter composting

Schmidt, Amy M 07 August 2010 (has links)
In-house windrow composting of broiler litter has been studied to reduce microbial populations between flocks. Published time-temperature goals are used to determine the success of the composting process for microbial reductions. Spatial and temporal density of temperature measurement can influence the ability to determine what portion of a windrow pile has achieved specified time-temperature goals. Based on this motivation, an investigation of the heating profile in windrowed litter and the identification of the effects of spatial and temporal sampling densities on the prediction of the heating profile in windrowed broiler litter were executed. Likewise, an investigation of the effects of moisture content on heat generation during composting of broiler litter was conducted. Ultimately, the research projects were designed with the goal of determining the efficacy of windrow composting as a treatment method for reducing microbial populations in broiler litter and to produce recommendations for the implementation of future windrow temperature monitoring investigations. While past investigations have reported success of windrow composting for microbial population reductions, a lack of intense spatial and temporal temperature monitoring has likely mis-represented the pile heating profile and resultant effects on microbial populations.
33

Accelerated Composting of Hardwood Bark Amended with Organic and Inorganic Fertilizer

Bakhshizadeh, Hoda 15 December 2012 (has links)
The objectives of this study were: 1) To evaluate short-term composting of hardwood bark with combinations of poultry litter and ammonium nitrate and 2) To determine the suitability of composted material for ornamental plant media. In a 3-month accelerated composting study, hardwood bark was amended with (20% & 40%) poultry litter, (1% & 2%) ammonium nitrate, or unamended. Composting was run in fifteen 35- gallon containers and samples were collected at day 0, 45, and 90 for pH, moisture content, carbon-to-nitrogen ratio, compost maturity, toxicity, and green house evaluations. The amendment containing 40% poultry litter showed significantly higher weight reduction than others at days 45 and 90. Also, this treatment showed significantly higher mass weight in transplanted zinnia and gardenia than other treatments and was comparable to commercial media. Overall, results indicated that the amendment of hardwood bark with poultry litter could produce comparable product to currently used commercial container media.
34

Evaluating the Hazard of Land Applying Composted Diazinon Waste Using Earthworm Biomonitoring

Leland, Jarrod Ethan 11 September 1998 (has links)
A process for disposing of pesticide rinsewater generated from the rinsing of application equipment is being developed at Virginia Polytechnic Institute and State University. This process involves the sorption of pesticides onto an organic matrix followed by degradation in a composting environment. We are now evaluating the hazards that might be associated with land-applying composted pesticide waste. Diazinon was the first pesticide selected for evaluation, which consisted of two studies. The first used the earthworm species Eisenia foetida to evaluate the toxicity of soil amended with composted diazinon waste. The second study determined the bioavailability of delta-2-14C-diazinon and its degradation products to E. foetida in soil amended with composted delta-2-14C-diazinon. Results from the first study indicate that uncomposted diazinon sorbent and 30-day composted diazinon sorbent were toxic to E. foetida at sublethal and lethal levels. However, E. foetida exposed 60-day composted diazinon sorbent did not experience mortality or demostrate sublethal effects commonly associated with acetylcholinesterase inhibition. Earthworms exposed to diazinon that was uncomposted or composted for 30 days in the radiolabelled study experienced higher mortality than in the field study. After 30 and 60 days of composting 14C-diazinon became unextractably incorporated into organic matter and very little was mineralized. Earthworms were shown to accumulate radioactivity when exposed to soil amended with 60- day composted delta-2-14C-diazinon. The majority of this radioactivity was unextractably bound to earthworm tissue and that which was extractable contained only trace levels of delta-2-14C-diazinon. Based on the absence of toxicity in the field study and the low levels of 14C-diazinon present in earthworm tissues, 60 days of composting appears to greatly reduce the hazard that diazinon rinsate poses to E. foetida. / Master of Science
35

In-vessel composting model with multiple substrate and microorganism types

Woodford, Philip Bernard January 1900 (has links)
Doctor of Philosophy / Department of Biological & Agricultural Engineering / James K. Koelliker / This research provides a deterministic model of in-vessel composting, based on Monod’s growth kinetics, to mirror biological-mixture decomposition. Existing models predict temperature curves assuming a single temperature-range organism, using a soluble (simple sugar) substrate, with bacteria as the microorganism, and they ignore the different temperature range environments that impact the growth rates of mesophilic and thermophilic microorganisms. The new computer-simulated model, written in MATLAB® by The MathWorks, has six unique features. First, three major carbon chain substrate groups are utilized: soluble, hemicellulose/cellulose, and lignin. An additional substrate group is used for inert substrates. Second, three major microorganism groups are utilized: bacteria for soluble substrate, actinomycetes for cellulose substrate, and fungi for lignin substrate. Third, two temperature-range microorganisms are included: mesophilic and thermophilic. Fourth, the model accounts for the death of microorganisms as the temperature transitions between the temperature ranges. Most of the dead cellular mass is returned to soluble substrate for reutilization and a portion is considered resistant to biological decomposition and is added into the lignin substrate. Fifth, stoichiometric equations account for substrate and microorganism compositions, oxygen and nitrogen requirements, and carbon dioxide and water production. Sixth, the relationship between biological activity and water is better defined. Experimental research was conducted to validate the model. Laboratory analysis distinguished the substrate types. The results indicate the model did differentiate between different levels of substrate types, and the mesophilic and thermophilic microorganism types. Also, the model did differentiate between the bacteria, actinomycetes and fungi. The influence was small, however, because of the different maximum growth rates of the three types of microorganisms. Returning dead microbes to the substrate pools as a result of temperature transitions affected the model results positively. Additional research is needed to account for the influence of volume reduction, develop a better microbial growth curve, include particle size influence, add temporal temperature fluctuations to the external boundary conditions, incorporate pH and nitrogen availability, and develop a three-dimensional model. KEY WORDS. Aerobic composting, mathematical composting model, substrate types, microorganism types, microorganism temperature range, mesophilic, thermophilic, microbial death utilization, moisture composting relationship.
36

Compostability of municipal and industrial wastewater sludge : physical, chemical and biochemical transformations and end-product characteristics

Potgieter, Johannes Jacobus Christian January 2013 (has links)
Can composting save the world from its human generated biological waste problem and give a diversifying organic agriculture a much needed boost at the same time? The age old natural process of composting has been well researched and documented in scientific and other literature. Thermophilic composting transforms biological/organic waste into a stable plant and soil friendly material (compost) that has been sanitised through high temperature and humified at the same time – a true miracle of nature. Mixtures for thermophilic composting can be formulated fairly accurately from their water, C and N content. The pH needs to be within an acceptable range (5-8) but can be adjusted with agricultural lime if needed. The EC and ash content of sludge, together with the C and N content, are fairly reliable indicators of available bio-chemical energy for composting. Monitoring the temperature and water content gives sufficient feedback for proper management of the process. Bio-chemical transformations in composting material tell the tale of the microbial processes at the heart of composting and humification. The quality of compost depends largely on the quality of the raw materials used, even if mixture formulation and process management is effective. The study firstly evaluated the compostability of various types of WWS and eucalyptus sawdust bulking agent with the focus on the known requirements and conditions for thermophilic aerobic composting. This entailed a composting experiment during which the sludge and bulking agent were characterised, feedstock mixtures formulated and certain composting conditions (temperature and water content) and feedstock characteristics (pH, EC and ash content) monitored over time as piles were managed through turning, sampling and watering. Secondly, the study evaluated the quality of compost produced from various types of WWS and eucalyptus sawdust bulking agent as influenced by the raw material and initial feedstock characteristics, microbial dynamics and environmental conditions during composting and as indicated by certain chemical and biochemical transformations (including OM decomposition) during composting and end product (compost) characteristics. Tracking the chemical and biochemical evolution during composting in the four treatments entailed the laboratory analyses of a variety of signature characteristics for samples taken at the start of composting, at the end of the thermophilic phase when pile temperature decreased to below 40ºC and at the end of the curing phase of composting when the temperature of piles did not exceed ambient temperature. Finally, a seedling emergence bioassay was performed as a direct test of compost maturity and quality. The main findings of this study are that dewatered, activated sludge has a high level of thermophilic compostability with Eucalyptus sawdust as bulking agent. Dried, digested sludge has a low level of compostability with Eucalyptus sawdust as bulking agent mainly because of the anaerobic digestion that depleted the C and bio-chemical energy in the sludge. Little value is added to digested sludge through composting with eycalyptus sawdust except that it probably facilitated a further “curing” of the already stable material. Overall, dewatered ACT-MUN sludge and eucalyptus sawdust produced the compost of highest quality and stability/maturity in a volume ratio of 1:4 (sludge:sawdust). Dewatered ACT-IND sludge and eucalyptus sawdust produced an interesting compost of high stability/maturity with a high level of humification and medium fertility status. Increasing the sludge:sawdust ratio closer to 1:4 (volume) will enhance the chemical quality of this good compost. Dried DIG-MUN sludge and eucalyptus sawdust produced a stable compost of very low pH, relatively low fertility, poor physical character and high risk of phytotoxicity. Composting is a great option for WWS treatment that deserves a lot more attention in South Africa. / Dissertation (MSc Agric)--University of Pretoria, 2013. / gm2014 / Plant Production and Soil Science / unrestricted
37

Comparison of home-composting and large-scale composting  for organic waste management in Québec, Canada.

Joly, Elsa January 2011 (has links)
The management of the organic fraction of municipal solid waste has become a major issue lately in the province of Québec, Canada. Most of it is landfilled today, which increases the burden on landfills and is environmentally unsound. In order to comply with new government guidelines, municipalities have to develop solutions to recover and recycle organic waste. In this context, this study examines two solutions for treating organic waste: home-composting and a separate biodegradable waste collection system combined with large-scale composting. The two scenarios are compared in terms of costs and environmental performance to a reference scenario where all waste is landfilled, using as a case study a fictional city of 50 000 inhabitants. Results indicate that a centralized collection system, combined to large-scale composting, has greater environmental benefits than home-composting. It cuts greenhouse gas emissions by 240% compared to the reference scenario, while emissions from home-composting remain at the reference level. However, when compared to the reference scenario, home-composting reduces waste management costs by 15% while they represent an increase of 4% with large-scale composting. The study concludes that separate biodegradable waste collection combined to large-scale composting is the best way for a municipality to achieve high environmental goals, despite a slight increase of municipal costs. The participation rate of citizens is suggested to be a crucial parameter for the success of organic waste management in the two scenarios and it should be enhanced by different means to ensure the successful implementation of the chosen solution.
38

Valorização de resíduos sólidos orgânicos para grandes geradores: avaliação da viabilidade técnica de equipamentos compactos / Appreciation of organic solid waste for large generators: assessment of technical feasibility for compact equipment\'s

Beltrame, Fernando Antonio 03 August 2018 (has links)
Após vinte e um anos de tramitação em processo legislativo, no Brasil, a Lei da Política Nacional de Resíduos Sólidos (PNRS) foi aprovada em 2 de agosto de 2010. Apesar do arcabouço regulatório da importância deste marco legal, ainda há muito a evoluir com relação ao tratamento e destinação dos resíduos sólidos no país. Em 2016, foram gerados aproximadamente 71,3 milhões de toneladas de resíduos sólidos urbanos em todo o território nacional, dos quais 41% foram dispostos em locais inadequados como lixões, terrenos baldios ou aterros controlados. Por volta de 50% deste resíduo gerado é constituído por resíduo orgânico (restos de alimento, cascas de frutas e hortaliças), material reconhecido como reciclável, pela Política Nacional de Resíduos Sólidos. No entanto, menos de 1% do resíduo orgânico é transformado em composto orgânico, isso significa que ao invés de os seus nutrientes retornarem à cadeia produtiva e à terra, geram impacto ambiental e problemas sanitários. Este cenário se repete no município de São Paulo e em todas as grandes cidades brasileiras. A presente dissertação, neste contexto, tem por objetivo avaliar diferentes inóculos que aceleram o processo de degradação dos resíduos orgânicos, bem como os parâmetros do processo de compostagem para o desenvolvimento de um equipamento de compostagem automatizado, compacto, eficiente e de simples operação, para uso em centros urbanos. O percurso metodológico de investigação considerou: levantamento dos principais inóculos para compostagem do mercado e desenvolvidos de forma artesanal; produção dos inóculos para teste; construção de protótipos de equipamentos de compostagem com diversas características para se avaliar os principais parâmetros físicos que interferem no processo de compostagem; realização de análises laboratoriais de composição microbiana, pH, umidade, Carbono/Nitrogênio e respiração microbiana; pesquisa de patentes nacionais e internacionais de equipamentos de compostagem automatizados; realização de testes de bancada com os inóculos e equipamentos desenvolvidos; visitas a diversos centros de compostagem; e construção de protótipo final, conforme parâmetros levantados na pesquisa. Como resultados pôde-se identificar os inóculos EM (microrganismos eficientes) e serapilheira como os mais adequados ao sistema de compostagem proposto, com a melhor composição de fungos e bactérias, bem como o desenvolvimento de protótipos com as características e controles necessários para a produção de um composto de qualidade, dentro dos padrões exigidos por lei e nas condições de tempo e área demandadas pelo mercado nacional. / After twenty-one years in the legislative process in Brazil, the National Policy on Solid Waste was approved on August 2nd, 2010. Despite the importance of this legal framework, there is still much to be done in relation to treatment and disposal of solid waste in the country. In 2016, approximately 71.3 million tons of municipal solid waste were generated throughout the country, of which 41% were disposed of in unsuitable places such as dumps, \"wastelands\" or controlled landfills. About 50% of this waste is composed of organic waste (leftovers, fruit peels and vegetables), a material recognized as recyclable by the National Solid Waste Policy. However, less than 1% of the organic waste is transformed into organic compost, which means that instead of its nutrients returning to the production chain and to the land, they generate environmental impact and sanitary problems. This scenario is repeated in the City of São Paulo and in all the major Brazilian cities. The aim of this dissertation is to evaluate different inoculums that accelerate the degradation process of organic residues, as well as the parameters of the composting process for the development of an automated, compact, efficient and simple operation of composting equipment, used in urban centers. The methodological course of investigation considered: survey of the main market inoculants for composting and produce and test our own inoculants; production of inocula for testing; construct a composting equipment with several characteristics to evaluate the main physical parameters that interfere in the composting process; laboratory analysis of microbial composition, pH, humidity, Carbon / Nitrogen and microbial respiration; research of national and international patents of automated composting equipment; performing bench tests with inocula and equipment developed; visits to various composting centers; and final prototype construction, according to the parameters raised in the research. As a result of it was possible to identify that the inoculum EM (efficient microorganisms) and litter (\"Serapilheira\") as the most suitable to the proposed composting system, with the best composition of fungi and bacteria, as well as the development of prototypes with the necessary characteristics and controls for the production of a quality fertilizer, within the standards required by law and in the time and area conditions demanded by the national market.
39

Valorização de resíduos sólidos orgânicos para grandes geradores: avaliação da viabilidade técnica de equipamentos compactos / Appreciation of organic solid waste for large generators: assessment of technical feasibility for compact equipment\'s

Fernando Antonio Beltrame 03 August 2018 (has links)
Após vinte e um anos de tramitação em processo legislativo, no Brasil, a Lei da Política Nacional de Resíduos Sólidos (PNRS) foi aprovada em 2 de agosto de 2010. Apesar do arcabouço regulatório da importância deste marco legal, ainda há muito a evoluir com relação ao tratamento e destinação dos resíduos sólidos no país. Em 2016, foram gerados aproximadamente 71,3 milhões de toneladas de resíduos sólidos urbanos em todo o território nacional, dos quais 41% foram dispostos em locais inadequados como lixões, terrenos baldios ou aterros controlados. Por volta de 50% deste resíduo gerado é constituído por resíduo orgânico (restos de alimento, cascas de frutas e hortaliças), material reconhecido como reciclável, pela Política Nacional de Resíduos Sólidos. No entanto, menos de 1% do resíduo orgânico é transformado em composto orgânico, isso significa que ao invés de os seus nutrientes retornarem à cadeia produtiva e à terra, geram impacto ambiental e problemas sanitários. Este cenário se repete no município de São Paulo e em todas as grandes cidades brasileiras. A presente dissertação, neste contexto, tem por objetivo avaliar diferentes inóculos que aceleram o processo de degradação dos resíduos orgânicos, bem como os parâmetros do processo de compostagem para o desenvolvimento de um equipamento de compostagem automatizado, compacto, eficiente e de simples operação, para uso em centros urbanos. O percurso metodológico de investigação considerou: levantamento dos principais inóculos para compostagem do mercado e desenvolvidos de forma artesanal; produção dos inóculos para teste; construção de protótipos de equipamentos de compostagem com diversas características para se avaliar os principais parâmetros físicos que interferem no processo de compostagem; realização de análises laboratoriais de composição microbiana, pH, umidade, Carbono/Nitrogênio e respiração microbiana; pesquisa de patentes nacionais e internacionais de equipamentos de compostagem automatizados; realização de testes de bancada com os inóculos e equipamentos desenvolvidos; visitas a diversos centros de compostagem; e construção de protótipo final, conforme parâmetros levantados na pesquisa. Como resultados pôde-se identificar os inóculos EM (microrganismos eficientes) e serapilheira como os mais adequados ao sistema de compostagem proposto, com a melhor composição de fungos e bactérias, bem como o desenvolvimento de protótipos com as características e controles necessários para a produção de um composto de qualidade, dentro dos padrões exigidos por lei e nas condições de tempo e área demandadas pelo mercado nacional. / After twenty-one years in the legislative process in Brazil, the National Policy on Solid Waste was approved on August 2nd, 2010. Despite the importance of this legal framework, there is still much to be done in relation to treatment and disposal of solid waste in the country. In 2016, approximately 71.3 million tons of municipal solid waste were generated throughout the country, of which 41% were disposed of in unsuitable places such as dumps, \"wastelands\" or controlled landfills. About 50% of this waste is composed of organic waste (leftovers, fruit peels and vegetables), a material recognized as recyclable by the National Solid Waste Policy. However, less than 1% of the organic waste is transformed into organic compost, which means that instead of its nutrients returning to the production chain and to the land, they generate environmental impact and sanitary problems. This scenario is repeated in the City of São Paulo and in all the major Brazilian cities. The aim of this dissertation is to evaluate different inoculums that accelerate the degradation process of organic residues, as well as the parameters of the composting process for the development of an automated, compact, efficient and simple operation of composting equipment, used in urban centers. The methodological course of investigation considered: survey of the main market inoculants for composting and produce and test our own inoculants; production of inocula for testing; construct a composting equipment with several characteristics to evaluate the main physical parameters that interfere in the composting process; laboratory analysis of microbial composition, pH, humidity, Carbon / Nitrogen and microbial respiration; research of national and international patents of automated composting equipment; performing bench tests with inocula and equipment developed; visits to various composting centers; and final prototype construction, according to the parameters raised in the research. As a result of it was possible to identify that the inoculum EM (efficient microorganisms) and litter (\"Serapilheira\") as the most suitable to the proposed composting system, with the best composition of fungi and bacteria, as well as the development of prototypes with the necessary characteristics and controls for the production of a quality fertilizer, within the standards required by law and in the time and area conditions demanded by the national market.
40

Efektivní nakládání s biologicky rozložitelným odpadem / Effective management of biological waste

Petříčková, Alena January 2017 (has links)
Theoretical part of present study gives a comprehensive overview of the methods used for the disposal of biodegradable waste with emphasis placed on highly effective techniques. Composting process is studied in detail and machinery used is thoroughly described. Acquired information from extensive research was applied to create a model of composting plant. Operation manual for this specific model forms part of the study. Afterwards various decomposing scenarios are analyzed and their economic sustainability is evaluated.

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