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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.
461

Enhancement of the biodegradability of grain distillery wastewater to improve upflow anaerobic sludge blanket reactor efficiency

Gie, Lowna-Marie 12 1900 (has links)
Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2007. / The distillery industry generates large volumes of heavily polluted wastewater and thus effective wastewater treatment is essential. It has been reported that a chemical oxygen demand (COD) reduction of more than 90% can be achieved when wine distillery wastewater (WDWW) is treated in an upflow anaerobic sludge blanket (UASB) reactor. The first objective of this study was to investigate UASB treatment of WDWW and to try to enhance the efficiency by using ozonation treatments. Secondly, the impact of grain distillery wastewater (GDWW) on UASB granules was determined. The third objective was to determine whether ozonation and enzymatic treatment combinations might improve the biodegradability of GDWW and thus make GDWW more amenable to UASB treatment. It was found that UASB treatment combined with ozonation improved the WDWW treatment efficiency. When diluted WDWW (chemical oxygen demand COD = 4 000 mg.L-1) was ozonated (dose = 47 mg.L-1) in a 50 L venturi circulating contactor system, the COD reduction was 7%. When WDWW was treated in a laboratory-scale UASB reactor (substrate pH = 7.0, COD = 4 000 mg.L-1 and organic loading rate (OLR) = 4.0 kg COD.m-3.d-1), the COD reduction was 92%. When the UASB treatment was combined with either pre- or postozonation, the COD reduction was 94 and 96%, respectively. When UASB treatment was combined with pre- and post-ozonation, a COD reduction of 98% was achieved. The activity of the UASB granules was also found to improve over time, despite the addition of the ozonation treatment. It has been reported that operational problems occur when GDWW is treated in an UASB reactor as a result of the encapsulation of the granules. This was confirmed when granules from a full-scale UASB treating WDWW became encapsulated in a layer after being exposed to GDWW (COD = 4 000 mg.L-1) for 24 d. The results showed that the lipid content of the granules increased from 1.25 to 60.35 mg lipid.g-1 granule over the 24 d exposure period. Therefore, granules exposed to GDWW were encapsulated in a lipid-rich layer and as a result the contact between the GDWW and microbial consortium in the granules was reduced. The operational problems found during the industrial UASB treatment of GDWW were ascribed to the encapsulation of the granules. Combinations of ozonation (dose = 1 476 mg.L-1) generated in a 2 L bubble column and enzymatic treatments (1% FogFreeTM (FF) dosage and 2 d incubation at 35°C) were found to improve the biodegradability of GDWW. This improvement was in terms of lipid reduction in GDWW, granule activity and visual appearance of the encapsulating layer of the granules. The highest lipid reduction (90%), highest granule activity, lowest lipid content of the granules (3.74 ± 0.10 mg.g-1 granule) and best visual appearance were achieved in ozonated GDWW treated with 1% FF, followed by just ozonation. The higher lipid reduction and subsequent higher granule activity were ascribed to the reduction in lipids which resulted in the fact that fewer lipids were available to encapsulate the granules. As a result of the lipid reduction, the granule activity improved and the GDWW was made more amenable to UASB treatment. This study proved that UASB treatment combined with ozonation led to an enhancement of the treatment efficiency of WDWW. It was also found that the cause of the operational problems during UASB treatment of GDWW was as a result of the granules being encapsulated in a lipid-rich layer. It was established that treating GDWW prior to UASB treatment improved the biodegradability of GDWW. The data from the study showed that high lipid reduction in the GDWW directly led to better granule activity, lower granule lipid content and a thinner encapsulating layer. Based on the data from this study, it is recommended that GDWW be ozonated prior to other treatments because it can be done inline and the costs would be lower than that of enzymatic treatments.
462

A multi-parameter empirical model for mesophilic anaerobic digestion

Ogbonna, Emmanuel January 2017 (has links)
Anaerobic digestion, which is the process by which bacteria breakdown organic matter to produce biogas (renewable energy source) and digestate (biofertiliser) in the absence of oxygen, proves to be the ideal concept not only for sustainable energy provision but also for effective organic waste management. However, the production amount of biogas to keep up with the global demand is limited by the underperformance in the system implementing the AD process. This underperformance is due to the difficulty in obtaining and maintaining the optimal operating parameters/states for anaerobic bacteria to thrive with regards to attaining a specific critical population number, which results in maximising the biogas production. This problem continues to exist as a result of insufficient knowledge of the interactions between the operating parameters and bacterial community. In addition, the lack of sufficient knowledge of the composition of bacterial groups that varies with changes in the operating parameters such as temperature, substrate and retention time. Without sufficient knowledge of the overall impact of the physico-environmental operating parameters on anaerobic bacterial growth and composition, significant improvement of biogas production may be difficult to attain. In order to mitigate this problem, this study has presented a nonlinear multi-parameter system modelling of mesophilic AD. It utilised raw data sets generated from laboratory experimentation of the influence of four operating parameters, temperature, pH, mixing speed and pressure on biogas and methane production, signifying that this is a multiple input single output (MISO) system. Due to the nonlinear characteristics of the data, the nonlinear black-box modelling technique is applied. The modelling is performed in MATLAB through System Identification approach. Two nonlinear model structures, autoregressive with exogenous input (NARX) and Hammerstein-Wiener (NLHW) with different nonlinearity estimators and model orders are chosen by trial and error and utilised to estimate the models. The performance of the models is determined by comparing the simulated outputs of the estimated models and the output in the validation data. The approach is used to validate the estimated models by checking how well the simulated output of the models fits the measured output. The best models for biogas and methane production are chosen by comparing the outputs of the best NARX and NLHW models (each for biogas and methane production), and the validation data, as well as utilising the Akaike information criterion to measure the quality of each model relative to each of the other models. The NLHW models mhw2 and mhws2 are chosen for biogas and methane production, respectively. The identified NLHW models mhw2 and mhws2 represent the behaviour of the production of biogas and methane, respectively, from mesophilic AD. Among all the candidate models studied, the nonlinear models provide a superior reproduction of the experimental data over the whole analysed period. Furthermore, the models constructed in this study cannot be used for scale-up purpose because they are not able to satisfy the rules and criteria for applying dimensional analysis to scale-up.
463

Análise comparativa do desempenho de reator anaeróbio híbrido e reator de manto de lodo de fluxo ascendente (UASB) aplicados ao tratamento de esgoto sanitário

Hoyos, Nestor Leonel Muñoz January 2016 (has links)
O presente trabalho teve como objetivo principal avaliar a performance e a estabilidade operacional de uma nova configuração de um reator anaeróbio híbrido (RAH) que combina um filtro anaeróbio de fluxo descendente seguido de uma câmara de manta de lodo de fluxo ascendente comparativamente ao reator UASB nas mesmas condições operacionais aplicados ao tratamento de esgoto sanitário. A avaliação da eficiência de remoção de remoção da matéria orgânica e dos sólidos suspensos nos reatores piloto foi por meio de testes da DQO, DBO, sólidos em suspensão totais (SST) e dos sólidos em suspensão voláteis (SSV).Os reatores UASB e RAH foram operados por um período de 240 dias na fase 1 e 150 dias na fase 2 com vazão afluente de 1,6 m3/h e TDH de 11,8 h. O TDH médio na câmara de entrada do RAH foi de 2,7h e de 9,1h na câmara ascendente de manto de lodo. Os reatores piloto apresentaram capacidade de tratamento para suportar os choques de carga orgânica devido à variabilidade do esgoto bruto. A eficiência de remoção de matéria orgânica em termos de DQO foi de 66% e 59% para o UASB e RAH, a eficiência de remoção de SST atingiu valores de 65% e 63% respectivamente, aliás, o reator UASB apresentando valores superiores de desempenho operacional em quase todos os parâmetros de monitoramento dos processos de digestão anaeróbia os valores médios dos parâmetros DQO, DBO5, SST e SSV não tiveram diferenças estatisticamente significativas. O pH para os sistemas piloto esteve na faixa ideal para o desenvolvimento dos microorganismos anaeróbios (6,5 a 7,5) e a alcalinidade e os AGVs demonstraram estabilidade dos reatores, corroborados pela estabilidade do pH no interior de cada sistema. A velocidade ascensional na câmara de manta de lodo (0,45 m/h) não causou efeito adverso na qualidade do efluente em termos de SST, com valor médio de 39,8 mg/L, na mesma faixa observada no reator UASB (41,6 mg/L). Foi observada menor concentração de biomassa no reator RAH (distribuição vertical) comparativamente ao reator UASB segundo os perfis verticais de lodo, entretanto, este fato não comprometeu a sua eficiência de remoção de matéria orgânica e dos sólidos suspensos. A retirada do lodo de excesso dos sistemas piloto foi baseada na relação STV/ST para estimar a fração de biomassa, a freqüência do descarte foi de 1 vez por mês retirando o equivalente aos 10% do volume de lodo das tomadas que apresentaram uma fração de STV menor que 50%. É viável a implementação da turbidez como parâmetro de detenção de perdida de lodo no efluente dos reatores anaeróbios devido a que a turbidez e os SST apresentaram uma relação direta o que ajudaria a simplificar mecanismos de controle operacional para a toma de decisões nas estações de tratamento, sendo que a turbidez é um parâmetro de leitura rápida “in situ” e poderia advertir do excesso de lodo ao interior do reator. Foram empregados diferentes métodos titrimétricos para a determinação dos AGVs no efluente do RAH e UASB. Após análise dos resultados, recomenda-se o uso do método de KAPP e RIPLEY para a determinação dos AGVs pela simplicidade metodológica e pela rapidez na obtenção do resultado. / This study aimed to evaluate the performance and operational stability of a new configuration of a hybrid anaerobic reactor (RAH) combining an anaerobic filter downflow followed by a sludge blanket chamber upflow compared to UASB in same operating conditions applied to sewage treatment. The evaluation of organic matter removal and removal efficiency of suspended solids in the pilot reactor was by testing COD, BOD, total suspended solids (TSS) and volatile suspended solids (VSS). The RAH and UASB reactors were operated for a period of 240 days in the first phase and 150 days in phase 2 with the inlet flow of 1,6 m3/h and 11,8h TDH. The average TDH RAH in the inlet chamber was 2.7h and 9,1h in ascending chamber sludge blanket. Pilot reactors showed treatment capacity to support organic shock loads due to the variability of raw sewage. The organic matter removal efficiency in terms of COD was 66% and 59% for the UASB and RAH, the TSS removal efficiency reached values of 65% and 63% respectively, by the way, the UASB presenting performance values higher operational in almost all parameters of the monitoring anaerobic digestion processes mean values of the parameters COD, BOD5, TSS and VSS were not statistically significant differences. The pH for the pilot systems was in the ideal range for the development of anaerobic microorganisms (6,5 to 7,5) and alkalinity and Volatile Fatty Acids (VFA) demonstrated stability of reactors corroborated by the pH stability within each system. The upflow velocity in the sludge blanket chamber (0,45 m/h) caused no adverse effect on effluent quality in terms of TSS, with an average of 39,8 mg/L, in the same range observed in UASB (41,6 mg/L). It was observed lower concentration of biomass in the reactor RAH (vertical distribution) compared to UASB second vertical sludge profiles, however, this fact did not compromise its removal efficiency of organic matter and suspended solids. The withdrawal of the pilot systems excess sludge was based on TSV/TS ratio to estimate the biomass fraction, the frequency of disposal was 1 once a month by removing the equivalent of 10% of the outlets sludge volume that had a fraction of TSV less than 50%. The implementation of turbidity as sludge lost detention parameter is viable in the effluent of the anaerobic reactors due to turbidity and TSS showed a direct relationship which would help simplify operational control mechanisms for decision making in treatment plants, wherein the turbidity is a quick read parameter "in situ" and could warn of excess sludge inside the reactor. Different titrimetric methods were employed for the determination of VFA and the effluent from the UASB and RAH. After analyzing the results, we recommend the use of KAPP and RIPLEY method for the determination of VFA by methodological simplicity and speed in obtaining results.
464

Frakcionace biodegradabilní části komunálního odpadu k výrobě bioplynu a k výrobě pevného biopaliva / Fractionation of biodegradable municipal waste to produce biogas and solid biofuels production

VELEK, Jindřich January 2015 (has links)
The theses deals with the use of biologically degradable waste which needs to be processed and utilized in maximum amount. It is highly desirable to apply new and well-known technologies to treat such waste efficiently and not to dispose it in landfills unreasonably, as is the case at present. The paper describes landfilling, composting, anearobic digestion, mechanical and biological treatment of waste as well as various stages of the lability concerning fractions of organic compounds. The stages of the lability concerning fractions of organic compounds are in particular determining the best utilization of such biologically degradable waste in each technology. It is advisable in this case to apply the STEAM EXPOLOSTION or IFBB technology for treatment of biologically degradable waste. These technologies were used in the proposal for the utility model which specifies how to produce biogas or solid biofuel from waste.
465

Energetické využití biologicky rozložitelného komunálního odpadu Statutárního města České Budějovice / Energy utilization of the biodegradable component of municipal waste in the city of České Budějovice

SÝKOROVÁ, Žaneta January 2013 (has links)
My thesis is aimed at the possiblities of collecting and utilizing the biodegradable component of municipal waste in the specific environment of České Budějovice. The thesis includes a proposal to construct a municipal biogas plant to decrease the volume of mixed municipal waste. The goal of this part of the thesis is to compare expected costs and income of the project and determine the general economic indicators and evaluate the investment, so that the project can be either fully recommended or rejected.
466

Impact de prétraitements fongiques sur la méthanisation de la biomasse lignocellulosique, caractérisation des substrats transformés / Fungal pretreatment for lignocellulosic biomass anaerobic digestion

Rouches, Elsa 17 December 2015 (has links)
La méthanisation de la biomasse lignocellulosique est un des moyens les plus efficients pour la production d’énergie renouvelable. Cependant, la lignine présente dans cette biomasse est difficile à hydrolyser. Cette limite peut être surmontée grâce aux prétraitements. Parmi eux, les prétraitements peu couteux par pourritures blanches sont attrayants mais ils ont été peu appliqués pour la digestion anaérobie. La présente étude explore les prétraitements par pourritures blanches de la paille de blé afin d’en améliorer sa méthanisation. Tout d’abord, une étape de sélection a révélé l’efficacité de la souche Polyporus brumalis BRFM 985 puisque 43% de méthane supplémentaire ont été obtenus par gramme de matières volatiles par comparaison avec la paille témoin. En prenant en compte les pertes de matières occasionnées par le prétraitement, cela correspondait à 21 % d’amélioration par gramme de matière sèche initiale. De plus, il a été montré que l’addition de glucose durant le prétraitement limitait la délignification et donc la production de méthane du substrat. Puis, des échantillons prétraités furent obtenus lors d’un plan d’expérience visant à optimiser le prétraitement par P. brumalis BRFM 985 ; les paramètres du prétraitement testés étaient : la durée et la température de culture, l’humidité initiale du substrat et l’addition de métaux. Les surfaces de réponse de la production de méthane à partir de ces échantillons furent construites. La production optimale de méthane ne fut pas atteinte dans le domaine expérimental testé mais l’impact positif de l’addition de métaux fut démontré, ainsi que l’importance de choisir une durée de culture adaptée. Ensuite, l’usage de la technique de la pyrolyse-GC-MS pour évaluer l’efficacité du prétraitement fut étudié. Une estimation de la quantité de biomasse fongique avec cette méthode apparaît possible. Le ratio polysaccharides/lignine déterminé par py-GC-MS a permis de classer des échantillons prétraités selon leur biodégradabilité anaérobie. La digestion anaérobie en voie sèche (DAVS) de paille de blé prétraitée en réacteur pilote fut menée en batch avec recirculation des lixiviats. Durant le démarrage de la DAVS, un trop fort S/I mène à une accumulation d’acides gras volatils (AGV) et parfois à la défaillance de la DAVS. Néanmoins, de forts S/I permettent de traiter plus de substrat et augmentent la production de méthane par volume de réacteur. Avec la paille de blé, des S/I entre 2 et 3 (en matières volatiles) permettent un bon démarrage de la DAVS. Alors qu’un ratio AGV totaux/alcalinité inférieur à 0,6 correspond à des réacteurs stables en digestion anaérobie voie liquide ; cette limite semble mal adaptée à la DAVS. Il fut observé que la DAVS pouvait récupérer d’une phase d’acidification tant que le ratio AGV totaux/alcalinité était inférieur à 2 et que la concentration en AGV était inférieure à 10 g/L dans les lixiviats. Malgré une amélioration de la biodégradabilité et une phase de démarrage facilitée, le prétraitement fongique non optimisé ne permit pas d’améliorer la production de méthane après prise en compte des pertes de matière occasionnées par le prétraitement. / Anaerobic digestion of lignocellulosic biomass is one of the most efficient ways to produce renewable energy. However, lignin contained in this biomass is difficult to hydrolyze. This limitation can be overcome by pretreatments. Among them, low-cost white-rot fungi pretreatments seem attractive but were scarcely applied for anaerobic digestion. The current study investigates white-rot fungi pretreatments of wheat straw to improve its methane production. Firstly, a selection step has revealed the efficiency of Polyporus brumalis BRFM 985 since 43% more methane per gram of pretreated volatile solids were obtained compared to the control straw. Taking into account the dry weight loss occurring during the pretreatment, it still corresponded to 21% more methane per gram of initial total solids. Moreover, glucose addition during the pretreatment was shown to limit delignification and thus methane production from the substrate. Secondly, pretreated samples were obtained in an experiment device aiming to optimize the pretreatment with P. brumalis BRFM 985; tested pretreatments parameters were: culture duration, temperature, initial substrate moisture content and metals addition. Response surfaces of methane production from those samples were built. Optimum methane production was not reached in the experimental domain but the positive impact of metals addition was demonstrated, so as the importance to choose adequate culture duration. Then, the use of pyrolysis-GC-MS technic to access pretreatment efficiency was studied. Estimation of fungal biomass amount on wheat straw with this method appeared possible. Polysaccharides/lignin ratio determined with py-GC-MS allowed to classify some pretreated samples according to their anaerobic degradability. Solid State Anaerobic Digestion (SSAD) of wheat straw pretreated in pilot-reactor was carried out in batch with leachate recycle. During SSAD start-up phase, too high Substrate/Inoculum (S/I) ratio leads to Volatile Fatty Acid (VFA) accumulation and sometimes to reactor failure but with high S/I more substrate can be treated and methane production per reactor volume increases. With wheat straw, S/I between 2 and 3 (Volatile Solid basis) allow a successful start-up in SSAD. Whereas Total VFA/alkalinity ratio under 0.6 corresponds to stable wet anaerobic digestion; this limit seems not well adapted to SSAD. It was observed that SSAD reactors were able to recover from acidification phase when Total VFA/alkalinity was lower than 2 and with VFA concentrations inferior to 10 g/L in leachate. Despite the improvement of biodegradability and the facilitation of start-up phase, non-optimized fungal pretreatment did not improve methane production after taking into account mass losses occurring during the pretreatment.
467

Avaliação do desempenho de um reator anaeróbico compartimentado no tratamento de soro de queijo

Garcia, Fernanda Roberta Carnielo [UNESP] 26 February 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-26Bitstream added on 2014-06-13T18:50:32Z : No. of bitstreams: 1 garcia_frc_me_sjrp.pdf: 955704 bytes, checksum: 9806aa186a96e3aa2085f64f368e2358 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Este trabalho teve por objetivo avaliar o desempenho de um reator anaeróbio compartimentado no tratamento de soro de queijo. Para tanto, foi utilizado um reator de 4,9 L com cinco compartimentos, inoculados com lodo biológico granulado obtido de uma indústria da região. O reator foi operado com variados tempos de residência hidráulicos (1 a 4 dias) e concentrações de soro de queijo que variaram de 2500 a 11000 DQO mg L-1. Foram efetuadas as análises de Acidez e Alcalinidade, Turbidez, pH, Demanda Química de Oxigênio (DQO), Sólidos Voláteis (SV) e Sólidos Totais (ST). A partir dos resultados obtidos, e devido às características do reator, foi possível compreender a dinâmica do processo anaeróbio, nas fases acidogênica e metanogênica, tanto na geração / desaparecimento da alcalinidade / acidez, como na redução da carga orgânica. Na primeira etapa da pesquisa, o soro de queijo da alimentação do reator foi diluído a uma DQO de 2500 mg L-1, e o reator mantido em quatro tempos de residência hidráulicos (TRH), 4, 3, 2 e 1 dia. Com TRH 4 dias, a redução da DQO foi de 96,3%. Com TRH 3 dias, o reator apresentou um problema de queda no pH e, devido a isso, foi dividido em duas partes: a primeira na qual o reator apresentou uma redução de 97,3% e a outra na qual a redução foi de 89,4%. Com TRH 2 dias, a redução de DQO foi de 89,5%; e com TRH 1 dia a redução foi de 50,5%. A segunda etapa da pesquisa contou com um aumento da concentração de soro de queijo na alimentação do reator, DQO 6000 mg L-1, e TRHs de 3, 2 e 1 dia. Com TRH 3 dias, a redução de DQO foi 80,7%, com TRH 2 dias 74,0% e com TRH 1 dia, a redução foi 33,5%. Na terceira etapa da pesquisa, a concentração do soro foi elevada para uma DQO de 11000 mg L-1, sendo testado o TRH 3 dias e como a eficiência do reator na redução da DQO apresentou um baixo valor, 47,1%, nenhum outro TRH foi testado. / This study aimed to evaluate the efficiency of an anaerobic baffled reactor treating cheese whey. For this, it was used a five-compartment reactor, 4.9 L, inoculated with granular sludge obtained from a biological industry in the region. The reactor was operated at different hydraulic residence times (HRT) from 1 to 4 days and the concentration of cheese whey was of 2500 to 11000 mg COD L-1. The procedures included analyses of acidity and alkalinity, turbidity, pH, chemical oxygen demand (COD), volatile solids (VS) and total solids (TS).From the results shown and due to the characteristics of the reactor, it was possible to understand the dynamics of the anaerobic process at the acidogenic and methanogenic stages both in the generation / disappearance of alkalinity / acidity and in reducing the organic load. In the first stage of research, the cheese whey used for feeding the reactor was diluted to a 2500 mg L-1 COD. The reactor was maintained at four hydraulic residence times (HRT) of 4, 3, 2 and 1 days. At a HRT of 4 days, the reduction in the COD was 96.3%. At a HRT of 3 days, the reactor had a problem - a decrease in pH and because of that, it was divided into two parts: in the first part the reactor showed a reduction of 97.3% and in the second one, the reduction was of 89.4%. At a HRT of 2 days, the reduction in the COD was of 89.5%; and at a HRT of 1 day, the reduction was of 50.5%. During the second stage of the survey, there was an increase of the concentration of cheese whey while feeding the reactor, COD 6000 mg L-1, and at a HRT of 3, 2 and 1 day. At a HRT of 3 days, the reduction in the COD was of 80.7%; at a HRT of 2 days, it was 74.0% and at a HRT of 1 day, the reduction was of 33.5%. In the third stage of the study, the concentration of whey was increased to a COD of 11000 mg L-1, being tested at a HRT of 3 days and since the efficiency of the reactor in the COD reduction showed a low value, 47.1%, no other HRT was tested.
468

Codigestão anaeróbia de resíduos bovinos e suínos: caracterização química e produção de biofertilizante para uso em cultura de milho

Costa, Antonio Marcos Tubiana de 10 October 2014 (has links)
Ao abordar o tema contaminação ambiental, logo se recorda a quantidade de resíduos domésticos e urbanos, que são gerados nas cidades e metrópoles, os quais muitas vezes não recebem nenhum tipo de tratamento. Porém, problemas de contaminação ambiental também estão vinculados à agricultura, onde são gerados resíduos orgânicos com elevados potenciais poluidores. Dessa forma, o projeto objetivou estudar o processo de codigestão anaeróbia de dejetos bovinos e suínos oriundos de sistemas de produção de suínos e atividade pecuária leiteira, como alternativa para tratamento destes tipos de matrizes, além de investigar a eficiência do biofertilizante produzido a partir das matrizes de resíduos em cultura de milho. Para isso, se coletaram amostras de dejetos de bovinos e suínos para caracterização e posterior utilização nos ensaios com tratamentos diferentes. Na sequência se fez a preparação das amostras para os ensaios utilizando-se de inoculos diferenciados (in natura, inoculo da rede de saneamento básico e inoculo isolado de dejeto bovino) com o propósito de avaliar a degradação dos dejetos via codigestão anaeróbia. Em cada ensaio citado se fizeram vinte tratamentos, via planejamento fatorial 2³, com seis pontos centrais, sendo as variáveis de entrada: tempo, fração de sólidos e razão de mistura; e as variáveis respostas (dependentes): pH, razão AV/AL, umidade, série de sólidos, razão SV/ST, redução de sólidos totais, DQO, redução de DQO, nitrogênio total, fósforo e potássio. Fez-se depois o estudo cinético do processo, se utilizando do ensaio in natura com proporção de mistura de 75% em dejeto suíno e 25% em dejeto bovino, com fração de sólidos de 8,9%, mediante Teste de Tukey. Após a estabilização da biomassa utilizada, fez-se a aplicação do biofertilizante em cultura de milho, comparando-se com fertilizante comercial (ureia), verificando-se o crescimento e desenvolvimento desta cultura. No planejamento fatorial se concluiu mediante análise de Tukey e considerando a importância de cada variável resposta que o ensaio in natura apresentou as melhores condições operacionais, pois se teve o maior número de variáveis respostas sendo consideradas satisfatórias, como razão AV/AL, razão SV/ST e redução da DQO. Observou-se durante o estudo cinético que a biomassa apresentou estabilização próxima aos vinte dias de tratamento, indicando a degradação orgânica dos dejetos em codigestão e produção de biofertilizante, o qual é mais estável e menos poluente ao ambiente, sendo utilizado como opção no processo de fertilização de culturas agrícolas como o milho. No que diz respeito à utilização do biofertilizante (40 kg.ha-1), notou-se semelhança deste se comparado à ureia (40 kg.ha-1) para o cultivo de milho, podendo ser uma alternativa interessante de destinação dos dejetos, diminuindo a poluição ambiental causada pelo manejo inadequado. / When discussing environmental contamination, just remember the amount of domestic and urban waste that are generated in towns and cities, which often do not receive any treatment. However, problems of environmental contamination are linked to agriculture, where organic waste with high potential polluters is generated. This way, the project had the objective of studying the anaerobic codigestion process of cattle and pig waste from the swine production systems and dairy farming activity, as an alternative to the treatment of these kinds of matrices, as well as to investigate the efficiency of biofertilizer matrices produced from the waste in cultured maize. For this, samples of manure from cattle and pigs were collected for characterization and subsequent use in the tests with different treatments. Then, the preparation of samples for the tests using the different inocula were made (in natura, inoculum of sanitation and inoculum isolated from bovine manure), in order to evaluate the degradation of waste via anaerobic codigestão. In each test mentioned twenty treatments were made, via 2³ factorial design with six central points, where the input variables: time, fraction of solids and mixing ratio; and the response variables (dependent): pH, ratio AV/AL, moisture, solids, ratio SV/ST, reduction of total solids, COD, reduction of COD, total nitrogen, phosphorus and potassium. It was made after the kinetic study of the process, using the test in natura mix ratio of 75% in swine manure and 25% in cattle manure with solid fraction of 8.9% by the Tukey test. After stabilization of the biomass used, there was the application of biofertilizers in crop maize compared with commercial fertilizer (urea), verifying the growth and development of this culture. In factorial design was completed by Tukey analysis and considering the importance of each variable response that the test in natura presented the best operating conditions, because it had the largest number of variable responses being considered satisfactory ratio as AV / AL, ratio SV / ST and COD reduction. It was observed during the kinetic study that biomass showed stabilization next to twenty days of treatment, indicating the degradation of organic waste in codigestão and biofertilizer production, which is more stable and less polluting to the environment, being used as an option in process fertilization of agricultural crops such as maize. Regarding the use of biofertilizers (40 kg.ha-1), this similarity was noted compared to urea (40 kg.ha-1) for the cultivation of maize and it may be an interesting alternative for allocation of waste, reducing environmental pollution caused by improper handling.
469

Codigestão anaeróbia de resíduos bovinos e suínos: caracterização química e produção de biofertilizante para uso em cultura de milho

Costa, Antonio Marcos Tubiana de 10 October 2014 (has links)
Ao abordar o tema contaminação ambiental, logo se recorda a quantidade de resíduos domésticos e urbanos, que são gerados nas cidades e metrópoles, os quais muitas vezes não recebem nenhum tipo de tratamento. Porém, problemas de contaminação ambiental também estão vinculados à agricultura, onde são gerados resíduos orgânicos com elevados potenciais poluidores. Dessa forma, o projeto objetivou estudar o processo de codigestão anaeróbia de dejetos bovinos e suínos oriundos de sistemas de produção de suínos e atividade pecuária leiteira, como alternativa para tratamento destes tipos de matrizes, além de investigar a eficiência do biofertilizante produzido a partir das matrizes de resíduos em cultura de milho. Para isso, se coletaram amostras de dejetos de bovinos e suínos para caracterização e posterior utilização nos ensaios com tratamentos diferentes. Na sequência se fez a preparação das amostras para os ensaios utilizando-se de inoculos diferenciados (in natura, inoculo da rede de saneamento básico e inoculo isolado de dejeto bovino) com o propósito de avaliar a degradação dos dejetos via codigestão anaeróbia. Em cada ensaio citado se fizeram vinte tratamentos, via planejamento fatorial 2³, com seis pontos centrais, sendo as variáveis de entrada: tempo, fração de sólidos e razão de mistura; e as variáveis respostas (dependentes): pH, razão AV/AL, umidade, série de sólidos, razão SV/ST, redução de sólidos totais, DQO, redução de DQO, nitrogênio total, fósforo e potássio. Fez-se depois o estudo cinético do processo, se utilizando do ensaio in natura com proporção de mistura de 75% em dejeto suíno e 25% em dejeto bovino, com fração de sólidos de 8,9%, mediante Teste de Tukey. Após a estabilização da biomassa utilizada, fez-se a aplicação do biofertilizante em cultura de milho, comparando-se com fertilizante comercial (ureia), verificando-se o crescimento e desenvolvimento desta cultura. No planejamento fatorial se concluiu mediante análise de Tukey e considerando a importância de cada variável resposta que o ensaio in natura apresentou as melhores condições operacionais, pois se teve o maior número de variáveis respostas sendo consideradas satisfatórias, como razão AV/AL, razão SV/ST e redução da DQO. Observou-se durante o estudo cinético que a biomassa apresentou estabilização próxima aos vinte dias de tratamento, indicando a degradação orgânica dos dejetos em codigestão e produção de biofertilizante, o qual é mais estável e menos poluente ao ambiente, sendo utilizado como opção no processo de fertilização de culturas agrícolas como o milho. No que diz respeito à utilização do biofertilizante (40 kg.ha-1), notou-se semelhança deste se comparado à ureia (40 kg.ha-1) para o cultivo de milho, podendo ser uma alternativa interessante de destinação dos dejetos, diminuindo a poluição ambiental causada pelo manejo inadequado. / When discussing environmental contamination, just remember the amount of domestic and urban waste that are generated in towns and cities, which often do not receive any treatment. However, problems of environmental contamination are linked to agriculture, where organic waste with high potential polluters is generated. This way, the project had the objective of studying the anaerobic codigestion process of cattle and pig waste from the swine production systems and dairy farming activity, as an alternative to the treatment of these kinds of matrices, as well as to investigate the efficiency of biofertilizer matrices produced from the waste in cultured maize. For this, samples of manure from cattle and pigs were collected for characterization and subsequent use in the tests with different treatments. Then, the preparation of samples for the tests using the different inocula were made (in natura, inoculum of sanitation and inoculum isolated from bovine manure), in order to evaluate the degradation of waste via anaerobic codigestão. In each test mentioned twenty treatments were made, via 2³ factorial design with six central points, where the input variables: time, fraction of solids and mixing ratio; and the response variables (dependent): pH, ratio AV/AL, moisture, solids, ratio SV/ST, reduction of total solids, COD, reduction of COD, total nitrogen, phosphorus and potassium. It was made after the kinetic study of the process, using the test in natura mix ratio of 75% in swine manure and 25% in cattle manure with solid fraction of 8.9% by the Tukey test. After stabilization of the biomass used, there was the application of biofertilizers in crop maize compared with commercial fertilizer (urea), verifying the growth and development of this culture. In factorial design was completed by Tukey analysis and considering the importance of each variable response that the test in natura presented the best operating conditions, because it had the largest number of variable responses being considered satisfactory ratio as AV / AL, ratio SV / ST and COD reduction. It was observed during the kinetic study that biomass showed stabilization next to twenty days of treatment, indicating the degradation of organic waste in codigestão and biofertilizer production, which is more stable and less polluting to the environment, being used as an option in process fertilization of agricultural crops such as maize. Regarding the use of biofertilizers (40 kg.ha-1), this similarity was noted compared to urea (40 kg.ha-1) for the cultivation of maize and it may be an interesting alternative for allocation of waste, reducing environmental pollution caused by improper handling.
470

Estudo cinético do processo de digestão anaeróbia de resíduos sólidos vegetais / Kinetics study of the process of anaerobic digestion of vegetable residual solids

Silva, Wellington Regis 27 July 2009 (has links)
Made available in DSpace on 2015-05-14T13:21:51Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1010298 bytes, checksum: a5a24de3f4abc4b3987d2584b46eea8f (MD5) Previous issue date: 2009-07-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The waste from fruit and vegetables and the discharge of domestic and industrial wastewaters in an unacceptable way cause serious problems for the majority of cities in Brazil and the rest of the world. The residues from fruit and vegetables and domestic and industrial wastewater could be treated jointly by the process of anaerobic digestion resulting in the production of energy and a reduction in negative environmental impacts. The principal objective of this work was to study the kinetics of the process of anaerobic biostabilization of vegetable residual solids (RSV), treated at different concentrations of total solids with the view to optimizing energy production and anaerobic biostabilization. To execute this study a completely mixed, compartmentalized anaerobic reactor comprising three compartments separated by glass plates with unit volumes of 25 litres, was designed, installed and monitored,. The resulting products from anaerobic biostabiliztion in the form of semi-solids were monitored weekly except for pH, total alkalinity and volatile fatty acids which jointly with biogas production were monitored twice weekly during a the total monitoring period of 294 days. The work was divided into two stages. In the first stage a substrate comprising twelve different types of vegetable solid waste with a total solids concentration equal to 75, 4 g/L was used. In the second stage the concentration of total solids applied to compartments C1, C2 and C3 were 40, 22.6 and 23.2 g/L respectively, with the with the level of humidity being adjusted by the addition of domestic sewage. The maximum percentage of methane in the biogas was 61.5% obtained in the first compartment (C1) of the reactor during the second experimental stage. The maximum kinetic constants for bioconversion (k) for COD total and soluble, TKN and sulphate during the first stage were respectively 3.86 x 10-2, 3.01 x 10-2, 4.75 x 10-2 and 2.13 x 10-2d-1. During the second stage of the study the values maximum obtained were 1.28 x 10-2, 1.90 x 10-2, 2.90 x 10-2 and 3.22 x 10-2d-1, for COD total and soluble, TKN and sulphate respectively. / O desperdício de frutas e verduras e o lançamento de águas residuárias domésticas ou industriais de forma inadequada representam sérios problemas para maioria das cidades do Brasil e do mundo. Os resíduos de frutas e verduras e as águas residuárias domésticas e industriais podem ser tratados de forma conjugada pelo processo de digestão anaeróbia, resultando no aproveitamento energético e na redução de impactos ao meio ambiente. O objetivo principal deste trabalho foi o estudo cinético do processo de bioestabilização anaeróbia de resíduos sólidos vegetais (RSV), tratados com diferentes concentrações de sólidos totais, visando o aproveitamento do potencial energético e consequentemente a bioestabilização anaeróbia do material orgânico. Para realização deste trabalho foi projetado, construído, instalado e monitorado um reator anaeróbio compartimentado de mistura completa, contendo três câmaras individuais de reação, construídas com placas de vidro, com volumes unitários de 25 litros. Os produtos resultantes do processo de bioestabilização anaeróbia que se encontravam na forma semi-sólida foram monitorados semanalmente, exceto pH, alcalinidade total e ácidos graxos voláteis que juntamente com o biogás foram monitorados duas vezes por semana; o período total de monitoração foi de 294 dias. O trabalho foi dividido em duas etapas. Na primeira etapa, o substrato constituído por doze diferentes tipos de (RSV) foi digerido a uma concentração de sólidos totais igual a 75,4 g/L. Para realização da segunda etapa, a concentração de sólidos totais aplicada às câmaras C1, C2 e C3 foram de 40; 22,8 e 23,2 g/L respectivamente, haja vista o teor de umidade do substrato preparado ter sido ajustado com adição esgoto doméstico. A porcentagem máxima de metano contido no biogás foi de 61,5%, obtida para primeira câmara de reação, no decorrer da segunda etapa. A produção máxima de biogás foi de 56 litros, também obtida na primeira câmara C1, ao longo da segunda etapa. Os valores máximos das constantes cinéticas de bioconversão (k) obtidos no decorrer da primeira etapa para DQOt, DQOs, NTK e sulfato foram respectivamente 3,86.10-2, 3,01.10-2, 4,75.10-2 e 2,13.10-2d-1. Durante a segunda etapa do trabalho os valores máximos obtidos foram de 1,28.10-2, 1,90.10-2, 2,90.10-2 e 3,22.10-2d-1 para DQOt, DQOs, NTK e sulfato, respectivamente.

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