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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.
161

Efeitos da inoculação na compostagem e vermicompostagem de resíduos sólidos verdes urbanos / Inoculation effects in the composting and vermicomposting of urban green solid residues

Suszek, Morgana 11 November 2005 (has links)
Made available in DSpace on 2017-07-10T19:24:38Z (GMT). No. of bitstreams: 1 Morgana Suszek.pdf: 1631457 bytes, checksum: e053e20fe847bb2e96307ad30b523a38 (MD5) Previous issue date: 2005-11-11 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Green solid residues coming from urban pruner and rests of agricultural products and also swineculture effluents have been showing as one of the main problems in the urban and rural areas, because their insuitable discards, being differents enviromment impacts. A alternative in order to treatment of these residues and effluents is the aerobic composting followed by vermicomposting process. In this study, was of these evaluated the integration of the composting and vermicomposting in the biostabilization of the urban green solid residues using swine wastewater and commercial activator, furthermore being checked the quality of the earthworm humus obtained. The vermicomposts produced showed similarities in the values of the C/N ratio, nitrogen and potass, in relation to the earthworm humus made with cattle manure, indicating the possibility of the green residues use in consortium with swine wastewater in the organic fertilizer production. Metals zinc and copper in the vermicomposts were detected, however, in concentrations which don´t infer risk of the human health, plants and soil contamination. The vermicomposts from organic composts showed, in average, lower value of that metals in relation to cattle manure vermicomposts. / Resíduos sólidos verdes provenientes de podas urbanas e de sobras de produtos hortifrutigranjeiros, assim como efluentes das atividades de suinocultura, apresentam-se como um dos principais problemas nas áreas urbanas e rurais, pois seus descartes de forma inadequada, provocam diversos impactos ambientais. Uma alternativa para o tratamento desses resíduos e efluentes é a compostagem aeróbia seguida pelo processo de vermicompostagem. Neste estudo, avaliou-se a integração da compostagem e vermicompostagem na bioestabilização de resíduos sólidos verdes urbanos, inoculados com água residuária da suinocultura e ativador comercial, ainda aferindo-se a qualidade do húmus de minhoca obtido. Os vermicompostos produzidos apresentaram semelhanças nos valores da relação C/N, nitrogênio e potássio, em relação ao húmus de minhoca feito com esterco bovino, indicando a possibilidade do uso dos resíduos verdes em consórcio com água residuária da suinocultura na produção de adubos orgânicos. Foram detectados os metais zinco e cobre nos vermicompostos, entretanto, em concentrações que não inferem riscos de contaminação ao solo, às plantas ou à saúde humana. Os vermicompostos de compostos orgânicos apresentaram, em média, valores mais baixos desses metais em relação ao vermicomposto de esterco bovino.
162

Adição de dejetos de bovinos de corte em processos biológicos de estabilização de cama de ovinos.

Cestonaro, Taiana 04 April 2013 (has links)
Made available in DSpace on 2017-05-12T14:46:50Z (GMT). No. of bitstreams: 1 Taiana.pdf: 1049826 bytes, checksum: 6b4cf77a1f5c7d5f54a87597ae4844ae (MD5) Previous issue date: 2013-04-04 / Sheep litter has in its composition manures incorporated to rice husk, which is a lignocellulosic material. Materials with this characteristic are stabilized for longer period of time and have restrictions on decomposing since they present strong fractions that can, sometimes, be inaccessible to micro-organisms. Some alternatives have been used in order to easy these nutrients recycling, for example its ordinary mixing with another residue. Thus, this essay aimed at evaluating vermicomposting, composting and anaerobic co-digestion applied to sheep litter mixed with cattle manure in order to provide available conditions to change such residues. Three assays were carried out from five ratios of sheep litter and cattle manure: 0:100, 25:75, 50:50, 75:25 and 100:0, which represented treatments T100, T75, T50, T25 and T0, respectively. The process of vermicomposting was carried out from November 2011 to march 2012. The material has undergone a preparation in order to eliminate toxic composts. Then, 0.88 kg of dry mass and 15 adult worms (Eisenia foetida) were allocated in the vermireactor. The ≥ 45% ash content was the stability parameter adopted in this assay. The composting piles were carried out from April to July 2012 in a covered area of concrete floor. Each pile had 200 kg of dry mass and received manual turnings two times a week during the first month and weekly from then on. Composting was supervised until the piles reached values close to room temperature, when the material was stabilized. The experimental period for anaerobic co-digestion occurred from May to October 2012. An entry mixture diluted with water was made in order to obtain a 5% content of total solids. And for residues fermentation, PVC bench scale bio-digesters were used to storage 6 L volume of such material. An anaerobic co-digestion was carried out in a batch system and observed until the curve of biogas production had decreased. In all assays, the adopted experimental design was completely randomized with univariate and multivariate statistics for data evaluation. The results showed that 50% of cattle manure was necessary in the mixture so that sheep litter could be efficiently absorbed in composting and in anaerobic co-digestion. This ratio generated a compost and biofertilizer with greater stability and content of nutrients as well as provided a larger scale of biogas production. In vermicomposting, the sheep litter showed potential to be used in a ratio up to 75% in mixture with cattle manure for Eisenia foetida specie development. However, greater ratios than 25% have decreased the vermicompost quality and in all assays, the rice husk was not transformed. / A cama de ovinos é composta por dejeções incorporadas a um material lignocelulósico, a casca de arroz. Materiais com essa característica apresentam maior tempo de estabilização ou limitações na decomposição, pois são constituídos de frações resistentes, por vezes inacessíveis aos microrganismos. Algumas alternativas são utilizadas para facilitar a reciclagem desses nutrientes, como a simples combinação com outro resíduo. Com este propósito, objetivou-se avaliar a vermicompostagem, a compostagem e a co-digestão anaeróbia de cama de ovinos em mistura com dejetos bovinos a fim de que fossem fornecidas condições adequadas para a transformação dos resíduos. Os três ensaios foram realizados a partir de cinco proporções de cama de ovinos e dejetos bovinos: 0: 100, 25: 75, 50: 50, 75: 25 e 100: 0, os quais representavam os tratamentos T100, T75, T50, T25 e T0, respectivamente. A vermicompostagem foi conduzida de novembro de 2011 a março de 2012. O preparo do material foi realizado a fim de que fossem eliminados os compostos tóxicos. Posteriormente, foram depositados 0,88 kg de massa seca e 15 minhocas adultas da espécie Eisenia foetida nos vermireatores. O conteúdo de cinzas de ≥ 45% serviu de parâmetro de estabilidade adotado neste ensaio. As leiras de compostagem foram conduzidas de abril a julho de 2012, em pátio coberto e com piso em concreto. Cada leira contou com 200 kg de massa seca e foram realizados revolvimentos manuais duas vezes por semana no primeiro mês e semanalmente a partir desse momento. A compostagem foi acompanhada até as leiras apresentarem valores de temperatura próximos a ambiente, quando considerou-se o material estabilizado. Na co-digestão anaeróbia, o período experimental foi de maio a outubro de 2012. A mistura de entrada, diluída com água, foi feita a fim de obter-se o teor de sólidos totais de 5%. Para fermentação dos resíduos, utilizaram-se biodigestores de PVC de bancada com volume útil de 6 L. A co-digestão anaeróbia foi conduzida em sistema batelada e acompanhada até o decréscimo da curva de produção de biogás. O delineamento experimental adotado em todos os ensaios foi inteiramente casualizado, com emprego de análises estatísticas univariadas e multivariadas para avaliação dos dados. Os resultados demonstraram a necessidade de 50% de dejetos de bovinos na mistura, para que a cama de ovinos pudesse ser absorvida eficientemente na compostagem e na co-digestão anaeróbia. Essa proporção deu origem a um composto e biofertilizante com maior estabilidade e conteúdo de nutrientes, além de proporcionar maiores produções de biogás. Em vermicompostagem, a cama de ovinos apresentou potencial de ser utilizada em proporção de até 75% na mistura com dejetos bovinos, para desenvolvimento da espécie Eisenia foetida. Porém, proporções superiores a 25% diminuíram a qualidade do vermicomposto. A casca de arroz não foi transformada em todos os ensaios.
163

Efeitos da inoculação na compostagem e vermicompostagem de resíduos sólidos verdes urbanos / Inoculation effects in the composting and vermicomposting of urban green solid residues

Suszek, Morgana 11 November 2005 (has links)
Made available in DSpace on 2017-05-12T14:48:01Z (GMT). No. of bitstreams: 1 Morgana Suszek.pdf: 1631457 bytes, checksum: e053e20fe847bb2e96307ad30b523a38 (MD5) Previous issue date: 2005-11-11 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Green solid residues coming from urban pruner and rests of agricultural products and also swineculture effluents have been showing as one of the main problems in the urban and rural areas, because their insuitable discards, being differents enviromment impacts. A alternative in order to treatment of these residues and effluents is the aerobic composting followed by vermicomposting process. In this study, was of these evaluated the integration of the composting and vermicomposting in the biostabilization of the urban green solid residues using swine wastewater and commercial activator, furthermore being checked the quality of the earthworm humus obtained. The vermicomposts produced showed similarities in the values of the C/N ratio, nitrogen and potass, in relation to the earthworm humus made with cattle manure, indicating the possibility of the green residues use in consortium with swine wastewater in the organic fertilizer production. Metals zinc and copper in the vermicomposts were detected, however, in concentrations which don´t infer risk of the human health, plants and soil contamination. The vermicomposts from organic composts showed, in average, lower value of that metals in relation to cattle manure vermicomposts. / Resíduos sólidos verdes provenientes de podas urbanas e de sobras de produtos hortifrutigranjeiros, assim como efluentes das atividades de suinocultura, apresentam-se como um dos principais problemas nas áreas urbanas e rurais, pois seus descartes de forma inadequada, provocam diversos impactos ambientais. Uma alternativa para o tratamento desses resíduos e efluentes é a compostagem aeróbia seguida pelo processo de vermicompostagem. Neste estudo, avaliou-se a integração da compostagem e vermicompostagem na bioestabilização de resíduos sólidos verdes urbanos, inoculados com água residuária da suinocultura e ativador comercial, ainda aferindo-se a qualidade do húmus de minhoca obtido. Os vermicompostos produzidos apresentaram semelhanças nos valores da relação C/N, nitrogênio e potássio, em relação ao húmus de minhoca feito com esterco bovino, indicando a possibilidade do uso dos resíduos verdes em consórcio com água residuária da suinocultura na produção de adubos orgânicos. Foram detectados os metais zinco e cobre nos vermicompostos, entretanto, em concentrações que não inferem riscos de contaminação ao solo, às plantas ou à saúde humana. Os vermicompostos de compostos orgânicos apresentaram, em média, valores mais baixos desses metais em relação ao vermicomposto de esterco bovino.
164

Suivi de maturation de composts mixtes par spectrométrie d'absorption et de fluorescence UV-visible / Monitoring of the maturation mixed composts by absorption and fluorescence spetrometry

Abaker, Madi Guirema 15 December 2016 (has links)
Le recyclage des déchets organiques est une préoccupation environnementaleimportante tant du point de vue énergétique que du point de vue du réchauffement climatique.Le compostage permet la transformation d'un déchet en produit, le compost, mais permetaussi d'augmenter le stockage du carbone dans les sols. Parmi les déchets, les boues de stationd'épuration sont un type de déchet urbain organique problématique et grandissant. La teneurélevée en matières organiques des boues peut ainsi être valorisée grâce au co-compostageavec des déchets verts. En effet, de nombreuses modifications chimiques se produisent aucours du processus de maturation d’un compost transformant les molécules simples ensubstances humiques bénéfiques aux sols. Cependant, il n'existe pas encore, à ce jour, detechniques rapides et universelles permettant de prédire la stabilité et la maturité du compost.Il est, en effet, nécessaire, pour suivre l'évolution d'un compost, de mesurer un nombreimportant de paramètres biologiques (test de respirométrie, test de germination), physiques(pH, température,…) et chimiques (potentiel d'oxydo-réduction, capacité d’échange de cations(CEC),…). Ceci n'est pas économiquement viable et rarement fait sur les plates-formes decompostage.L’objectif de cette étude a donc été d’identifier quel(s) paramètre(s) pourrai(en)t êtreutilisé(s) pour suivre aisément, sur une plate-forme de compostage, l’évolution du compostsur le terrain. Pour cela, nous avons suivi un co-compostage de boues de station d’épurationau cours du processus de maturation dans des composteurs de particuliers (sur place et enserre) et dans l’andain (sur place) afin d’observer l’effet de la taille mais aussi l’effet desconditions climatiques sur le processus de compostage. Une méthode d’extraction simple etpeu coûteuse de la matière organique extractible à l’eau (WEOM) utilisant un percolateur àeau à température ambiante est proposée. Ces extraits à l'eau ont été caractérisés par différentsparamètres, tels que le carbone organique dissous (CODWEOM) et l’azote total (NTWEOM) oules acides gras volatils (AGVWEOM) mais aussi par différentes techniques spectrométriquesd'absorption UV-Visible et de fluorescence. Pour l’absorption, des indices nous informent surl'aromaticité (SUVA254 WEOM), la taille moléculaire (E2/E3 WEOM), le poids moléculaire (E4/E6WEOM) et sur les substitutions des composés organiques (EET/EBZ WEOM) de la matièreorganique. En ce qui concerne la fluorescence, les indices d'humification HLIF, Kalbitz WEOM,Milori WEOM, Ra,c WEOM et Zsolnay WEOM ont été utilisés pour étudier les propriétés de laWEOM. De plus, à partir des matrices d'excitation-émission de fluorescence, les composantsCP/PARAFAC ont été déterminés. Au total, ce sont 23 paramètres qui ont été suivis au coursdu compostage.Les résultats permettent de discriminer les indices les plus pertinents pouvant êtreutilisés sur le terrain. Ces indices sont le SUVA254 WEOM, ainsi que les indices de Kalbitz WEOMet de Milori WEOM. La spectrométrie est une technique pertinente pour le suivi du compost surle terrain. Il n'a pas été décelé d'influence de la météorologie pour les composteursparticuliers, mais bien un effet de taille pour certains paramètres. / The recycling of organic waste is a major environmental concern both from anenergetic perspective and the global warming. The composting allows the conversion of wasteinto a product, the compost, and also the increase of carbon storage in soils. Among thedifferent wastes, sewage sludges are a problematic and increasing organic urban waste. Thehigh level of organic matter in sludges can be valorized by co-composting with green waste.Indeed, many chemical changes occur in the compost maturation process, transforming thesimple molecules in humic substances which are beneficial for soils. However, there are notyet, rapid and universal techniques which could predict the stability and the maturity ofcompost. It is necessary to measure a large number of biological (respirometric test, test ofgermination), physical (pH, temperature,…) and chemical (redox potential, cation exchangecapacity (CEC),…) parameters in order to follow the compost evolution. These measurementsare expensive and are rarely done on the composting platforms.Our objective was therefore to determine which parameter(s) could be used to easilymonitor the compost on the platform. For that, we followed a co-composting of sewagesludges during the maturation process in private compost bins (platform and greenhouse) andin swath (platform) in order to observe the size effect and the climatic condition effect on thecomposting process. An easy and little expensive extraction method of the water extractibleorganic matter (WEOM), using a percolator with water at room temperature was proposed.These water extracts were characterized by various parameters, such as dissolved organiccarbon (DOC WEOM) and total nitrogen (TN WEOM) or the content of volatile fatty acids, butalso, by various spectroscopic technics such as UV-Visible absorption and fluorescence. ForUV-Visible absorption, indices provide data on the aromaticity (SUVA254 WEOM), themolecular size (E2/E3 WEOM), the molecular weight (E4/E6 WEOM) and the substitutions oforganic compounds (EET/EBZ WEOM) of organic matter. Regarding fluorescence, humificationindexes such as HLIF, Kalbitz WEOM, Milori WEOM, Ra,c WEOM and Zsolnay WEOM were used tostudy the properties of WEOM. In addition, from the excitation-emission fluorescencematrices, CP/PARAFAC components were determined. All in all, 23 parameters werefollowed during the composting.We were thus able to distiguish the most relevant indices that can be used on theplatform. These indices are the SUVA254 WEOM and indices of Kalbitz WEOM and Milori WEOM.The spectroscopy is a relevant technique for monitoring the compost in the field. No impactof climatic conditions was revealed for the private compost bins, but a size effect for someparameters was observed.
165

Organic Household Waste in Developing Countries : An overview of environmental and health consequences, and appropriate decentralised technologies and strategies for sustainable management

Bobeck, Michaela January 2010 (has links)
<p>This paper reports on environmental impacts and health hazards as a result from inadequate management of organic household waste in developing countries. It gives details of water and soil contamination, air pollution and spread of diseases through expanding breeding grounds for pathogens, vectors and rodents. To manage this waste flow sustainably, decentralised composting and anaerobic digestions technologies have been studied to give an overall picture of existing appropriate technologies, including: windrow, box/bin/barrel, THM, aerated static pile, in-vessel, vermi, ARTI compact biogas digester and BARC’S NISARG-RUNA. Comparing different technologies showed that it is crucial to consider local conditions and markets when choosing which method to implement. However, the manual composting methods: windrow/box/bin/barrel, THM and vermi, are more likely to be appropriate in regard to current conditions in developing countries. A comparison between the environmental impacts of anaerobic digestion and composting did not result in a clear indication of which technology is most favourable. However, in the literature studied, biogas production showed an overall better energy balance, and composting a better result regarding nutrient recycling and xenobiotic compounds. In terms of the mitigation effect on global warming, the results varied essentially depending on the technology used and its loss of methane during the biogas production process. Finally, this paper investigates common constraints for implementation of the above-mentioned technologies, as well as recommendations for future projects. The study of general constraints revealed the need for directing attention to education, key consequences and benefits, co-operation, exchange of knowledge and bottom-up driving forces, for sustainable and successful implementation of organic household waste management practices in developing countries.</p>
166

Organic Household Waste in Developing Countries : An overview of environmental and health consequences, and appropriate decentralised technologies and strategies for sustainable management

Bobeck, Michaela January 2010 (has links)
This paper reports on environmental impacts and health hazards as a result from inadequate management of organic household waste in developing countries. It gives details of water and soil contamination, air pollution and spread of diseases through expanding breeding grounds for pathogens, vectors and rodents. To manage this waste flow sustainably, decentralised composting and anaerobic digestions technologies have been studied to give an overall picture of existing appropriate technologies, including: windrow, box/bin/barrel, THM, aerated static pile, in-vessel, vermi, ARTI compact biogas digester and BARC’S NISARG-RUNA. Comparing different technologies showed that it is crucial to consider local conditions and markets when choosing which method to implement. However, the manual composting methods: windrow/box/bin/barrel, THM and vermi, are more likely to be appropriate in regard to current conditions in developing countries. A comparison between the environmental impacts of anaerobic digestion and composting did not result in a clear indication of which technology is most favourable. However, in the literature studied, biogas production showed an overall better energy balance, and composting a better result regarding nutrient recycling and xenobiotic compounds. In terms of the mitigation effect on global warming, the results varied essentially depending on the technology used and its loss of methane during the biogas production process. Finally, this paper investigates common constraints for implementation of the above-mentioned technologies, as well as recommendations for future projects. The study of general constraints revealed the need for directing attention to education, key consequences and benefits, co-operation, exchange of knowledge and bottom-up driving forces, for sustainable and successful implementation of organic household waste management practices in developing countries.
167

Investigation of fermented waste and technologies of disposal / Fermentuotų atliekų tyrimai ir panaudojimo technologijos

Čepanko, Violeta 28 June 2010 (has links)
Object of the work – the fermented solid waste (substrate) and liquid (filtrate) fractions and their technologies of disposal. The key aim of this work is to analyse and evaluate the possibilities of using fermented wastes (sewage sludge, swine and poultry manure, fruit and vegetable waste, and grain) for fertilisation, composting and incineration taking into account their elementary composition and a level of pollution with heavy metals. Carry out an evaluation of gaseous pollutant (NOx) emissions from the process of incineration through the employment of a digital model. / Tyrimų objektas – fermentuotų atliekų kietoji (substratas) ir skystoji (filtratas) frakcijos bei jų panaudojimo technologijos. Darbo tikslas – išnagrinėti bei įvertinti fermentuotų atliekų (nuotekų dumblo, kiaulių ir vištų mėšlo, vaisių su daržovėmis bei žliaugto) panaudojimo tręšimui, kompostavimui bei deginimui galimybes atsižvelgiant į jų elementinę sudėtį ir užtaršos lygį sunkiaisiais metalais. Atlikti šių atliekų deginimo proceso metu išsiskiriančių dujinių teršalų (NOx) įvertinimą naudojant skaitinį modelį.
168

Aqueous Ammonia Treatment of Organic Material for Municipal Composting

MacIntyre, Stephen Eugene 13 September 2012 (has links)
Aqueous ammonia treatment of organic material to increase enzymatic digestibility is a growing area of research for animal fodder and biofuel production. The application of this treatment in the municipal composting process has not previously been investigated. Litterbags were used to investigate the effects of an aqueous ammonia treatment prior to composting on source-separated organic waste. The treatment consisted of soaking organic material in aqueous ammonia prior to introducing the material back into the composting process. Dry mass, ash content, ash-free dry mass, and water-solubility were measured. Three experiments were performed: one in the laboratory, one in an in-vessel system, and one in windrows. The aqueous ammonia treatment removed more dry mass compared to controls; however, the results indicate that the majority of the loss occurred during the soak. This treatment may be of interest for compost facilities if the leachate produced can be used in an economically beneficial way. / Ontario Centres of Excellence
169

Composting as a method for disposal of specified risk material and degradation of prions

Xu, Shanwei Unknown Date
No description available.
170

Organic waste - treatment options, opportunities and barriers

Taylor, Gary Howard January 2000 (has links)
There is approximately 14 million tonnes of biodegradable organic waste produced by households in the UK every year which must be treated or disposed of. The EC Directive on Landfill (1999/31IEC), is likely to lead to an increase in compo sting and anaerobic digestion as methods to treat the waste stream diverted from landfill. Householders play an important role in separating their waste, which, if not performed efficiently can lead to contamination of the organic waste stream, and hence the compost product. A survey is used to determine the attitude and behaviour of householders to waste issues. It was found that residents in the less affluent area were less likely to home compost and had a less favourable attitude towards environmental activities than residents in the affluent area. A comparison of compost from centralised composting schemes treating different organic waste streams found that compost derived from household waste was of a slightly poorer quality than that obtained from gardens/parks waste. As more waste is recycled as compost, it is becoming increasingly important to find alternative uses for compost. Leachability data are used to determine the environmental availability of Cd, Cu, Pb, and Zn contained in natural compost. Batch sorption data are used to determine uptake of additional Cd, Cu, Pb, and Zn by compost and assess its potential use in remediation work, as an alternative to natural materials such as peat. The relative binding of these additional metals to compost is found to be in the order Pb>Cu≈Cd>Zn. The sorption of metals on compost takes place, at least in part, by exchange of calcium bound to the compost and there is evidence that the sorption occurs in both the humic and non-humic sites in the compost. The use of compost to bind metals in remediation work is discussed.

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