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Suínos em diferentes fases de crescimento alimentados com milho ou sorgo: desempenho, digestibilidade e efeitos na biodigestão anaeróbiaMiranda, Adélia Pereira [UNESP] 20 February 2009 (has links) (PDF)
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miranda_ap_dr_jabo.pdf: 553828 bytes, checksum: d736c8d07571b50750a6e56f01d50fae (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Avaliaram-se dietas formuladas com milho ou sorgo para suínos nas fases inicial, crescimento e terminação sobre o desempenho dos animais, digestibilidade dos nutrientes, produção e características de fezes e urina e biodigestão anaeróbia dos dejetos. No ensaio de desempenho não foram verificadas diferenças quanto ao consumo médio diário de ração, ganho médio diário de peso e conversão alimentar. Foi realizado um ensaio de digestibilidade em cada fase de crescimento dos animais utilizando o método de coleta total de fezes, não se observando diferenças para coeficientes de digestibilidade da matéria seca e da energia bruta, coeficiente de metabolizabilidade, energia digestível e metabolizável. Os maiores coeficientes de digestibilidade da proteína bruta e proteína digestível foram verificados nos animais alimentados com dietas à base de milho na fase terminação. Para animais alimentados com dietas formuladas com sorgo foram verificados maiores valores de matéria seca digestível nas fases crescimento e terminação. Verificou-se maior produção média de fezes para animais alimentados com dietas formuladas com sorgo, gerando maiores coeficientes de resíduo. Os maiores teores de sólidos totais e voláteis foram verificados nas fezes de animais alimentados com dieta à base de milho, em todas as fases de crescimento. As concentrações médias dos nutrientes nas fezes e na urina variaram entre os tratamentos e fases. O abastecimento de 20 biodigestores indicou maiores reduções nos teores de sólidos voláteis e maiores produções de biogás quando se utilizaram fezes de suínos alimentados com dietas formuladas à base de milho. As concentrações médias dos nutrientes no afluente e efluente dos biodigestores variaram entre os tratamentos e fases. / There were evaluated diets formulated with corn or sorghum for pigs in the initial stages, growing and finishing on the growth performance of animals, digestibility of nutrients, production and characteristics of feces and urine and anaerobic digestion of pigs manure. In the test of growth performance were not found differences in the average daily consumption of feed, average daily weight gain and feed conversion. There was performed a test of digestibility at each stage of growth of animals using the total collection of feces, no difference was observed for digestibility coefficients of dry matter and gross energy, coefficient to metabolize, digestible and metabolizable energy. The highest rates of digestibility of crude protein and digestible protein were observed in animals fed with diets based on corn in the finishing stage. For animals fed diets formulated with sorghum there were observed higher values of digestible dry matter in growing and finishing phases. There was a greater average production of feces by animals fed with diets based on sorghum, generating higher coefficient of waste. The highest levels of total and volatile solids were found in the feces of animals fed with diets containing corn, in all the stages of growth. The average concentrations of minerals in feces and urine varied among treatments and stages. The supply of 20 anaerobic digesters indicated greater reductions in the volatile solids levels and greater production of biogas when using waste from pigs fed with diets based with corn. The average concentrations of minerals in the affluent and effluent in the anaerobic digesters varied among treatments and stages.
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Características quantitativas e qualitativas da cama de frango sob diferentes reutilizações: efeitos na produção de biogás e biofertilizanteFukayama, Ellen Hatsumi [UNESP] 18 July 2008 (has links) (PDF)
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fukayama_eh_dr_jabo.pdf: 525968 bytes, checksum: 2de8151a4f75d0ad1dc36da356f16775 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivou-se avaliar o efeito da reutilização de cama de quatro lotes de criações de frangos de corte sobre a produção de cama de frango, a produção de biogás e a utilização do biofertilizante para adubação de milho. No capítulo sobre produção de cama foram avaliados quatro reutilizações de cama de frangos de corte criados em um galpão comercial dividido em 12 boxes pertencente à Empresa Rei Frango em São Carlos - SP - Brasil. Para caracterização da produção de cama foi avaliado a quantidade de cama produzida na matéria seca (MS) e o coeficiente de resíduo (Cr), ou seja, a quantidade de resíduo por kg de peso vivo das aves. Na caracterização qualitativa, foram analisados os teores de macro, micronutrientes e metais na casca de amendoim e cama de frango. Com o acréscimo de casca de amendoim nova mais o aumento de excretas do lote anterior, houve aumento (P<0,05) na produção de cama (MS). Assim, o Cr aumentou de acordo com a reutilização da cama. Porém, quando se avalia o Cr acumulado, ou seja, a quantidade de resíduo por kg de peso vivo acumulado das aves dos lotes criados, não houve diferença (P>0,05). De forma geral, foi observado que, com a reutilização da cama houve aumento (P<0,05) na concentração de nutrientes na cama. Conclui-se que com a reutilização de cama é possível igualar ou diminuir os custos com a aquisição de nova cama, aumentar a quantidade de nutrientes na cama para ser utilizada como biofertilizante na agricultura e estabilizar ou diminuir o impacto ambiental com a produção de cama por ave produzida. No capítulo sobre biodigestão anaeróbia de cama de frangos, para cada lote de aves conduzidos foram realizadas duas avaliações de biodigestão anaeróbia, sendo 4 ensaios (camas de 1 a 4º reutilização) avaliados de 2 formas: as 4 camas foram avaliadas em diferentes épocas do ano e também avaliadas na mesma época... / The objective was to evaluate the effect of reuse of litter of four broiler breeding cycle on the broiler litter’ production, the biogas’ production and use of organic fertilizer for fertilization of maize. In the chapter on production of litter were evaluated four reuses of litter of broiler chickens reared in a commercial shed divided in 12 boxes belonging to Rei Frango Company in São Carlos - São Paulo - Brazil. To characterize the production of litter was assessed the amount of litter produced in dry matter (DM) and the coefficient of waste (CW), or the amount of waste per kg of live birds. In qualitative characteristics, were analyzed the levels of macro, micro and metals in the shell of peanuts and broiler litter. With the addition of new peanut shell, plus the increase of manure of the previous batch, there was an increase (P<0.05) in the production of litter (dry matter - DM). Thus, the increased CW according to the reuse of litter. But when assessing the cumulative CW, or the amount of waste per kilogram of body weight of accumulated lots of birds created, there was no difference (P>0.05). Overall, it was observed that with the reuse of the litter there was an increase (P<0.05) in the concentration of nutrients in litter. It follows that with the reuse of litter can be equal or lower cost for the purchase of new litter, increase the amount of nutrients in litter to be used as organic fertilizer in agriculture and keep or reduce the environmental impact to the production of litter by produced per bird. In the chapter on anaerobic digester with litter of broiler, for each batch of birds conducted two evaluations were made of anaerobic digester, and 4 trials (litters from 1 to 4 reuse) evaluated in 2 ways: the 4 litters were evaluated at different times of the year and also evaluated in the same season, totaling 8 tests. 24 digesters were used in batch, distributed... (Complete abstract click electronic access below)
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Anaerobic Digestion of Wastewater-Grown Algae Biomass with Optimized Biogas Yields and Nutrient SolubilzationRacz, Tiffany A 01 June 2018 (has links) (PDF)
Whole-cell algae biomass grown on nutrient-rich wastewater can be anaerobically digested to produce renewable heat and power, and to solubilize nutrients to grow additional algae biomass in a biorefinery system. In this study, algae biomass was grown on clarified primary wastewater in 33-m2 ponds at a 4-day residence time with sedimentation harvesting of the biomass. Lab digesters were used to test biogas yields and nutrient solubilization from the anaerobic digestion of algal biomass with and without mixing and with sonication as a pretreatment. Additionally, algae were fed to unheated and unmixed 1135-L pilot digesters to determine the effects of seasonal temperatures and organic loading rates on biogas yields and nutrient solubilization. Finally a scalability experiment was conducted to determine how well lab digesters replicated the nutrient solubilization and biogas yields of pilot digesters when they were operated at the same average daily temperature, and organic load. Overall, the tested conditions included mixing, temperature, feed pretreatment by sonication, scale, and organic loading. It was determined that unmixed, 20˚C digesters fed an average variable organic loading of 0.12 g VS/L-day had the highest yield of 0.3 L CH4/g VS fed. Compared to similarly operated digesters (30˚C, constant organic load 0.25 g VS/L-day) sonicated feed increased the mass yield of methane by 18% (0.28 L CH4/g VSintroduced), and mixing increased the mass yield of methane by 4% (0.25 L CH4/g VS). For the same digesters, sonicated feed increased the average nitrogen and phosphorus solubilization 10% and 11% with 36% N and 28% particulate P remaining, respectively. Eliminating mixing increased the average nitrogen and phosphorus solubilization by 13% and 27%, with 40% and 31% remaining as particulates, respectively. The pilot digesters produced an overall average mass yield of 0.19 L CH4/g VS, with a summer average of 0.46 L CH4/g VS and a winter average of 0.15 L CH4/g VS. For the pilot digesters, the average amount of remaining particulate nitrogen and phosphorus was 36% and 39%, respectively, with an average of 57% volatile solids destruction. Finally for the scale experiment, the pilot digesters exhibited mass and volumetric yields of 47% and 28% (0.19 L CH4/g VS; 0.011 L CH4/L-d) greater than the lab digesters. Additionally, the pilot digesters had 2% greater nitrogen solubilization and 29% less phosphorus solubilization with 23% N and 15% P, than the lab digesters. Based on these results, for a low organic load (0.01 – 0.65 g VS/L-day), it is recommended that digesters be unmixed and heated which, and have a longer winter residence time. In addition to benefiting methane yield and nutrient solubilization, these digester operating conditions would allow increased supply of nutrients to ponds during the most productive months when nutrients are being consumed at faster rates in the algae ponds.
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Características quantitativas e qualitativas da cama de frango sob diferentes reutilizações : efeitos na produção de biogás e biofertilizante /Fukayama, Ellen Hatsumi. January 2008 (has links)
Orientador: Jorge de Lucas Junior / Banca: Roberto Alves de Oliveira / Banca: Júlio Cesar Pascale Palhares / Banca: Nilva Kazue Sakomura / Banca: Mônica Sarolli Silva de Mendonça Costa / Resumo: Objetivou-se avaliar o efeito da reutilização de cama de quatro lotes de criações de frangos de corte sobre a produção de cama de frango, a produção de biogás e a utilização do biofertilizante para adubação de milho. No capítulo sobre produção de cama foram avaliados quatro reutilizações de cama de frangos de corte criados em um galpão comercial dividido em 12 boxes pertencente à Empresa Rei Frango em São Carlos - SP - Brasil. Para caracterização da produção de cama foi avaliado a quantidade de cama produzida na matéria seca (MS) e o coeficiente de resíduo (Cr), ou seja, a quantidade de resíduo por kg de peso vivo das aves. Na caracterização qualitativa, foram analisados os teores de macro, micronutrientes e metais na casca de amendoim e cama de frango. Com o acréscimo de casca de amendoim nova mais o aumento de excretas do lote anterior, houve aumento (P<0,05) na produção de cama (MS). Assim, o Cr aumentou de acordo com a reutilização da cama. Porém, quando se avalia o Cr acumulado, ou seja, a quantidade de resíduo por kg de peso vivo acumulado das aves dos lotes criados, não houve diferença (P>0,05). De forma geral, foi observado que, com a reutilização da cama houve aumento (P<0,05) na concentração de nutrientes na cama. Conclui-se que com a reutilização de cama é possível igualar ou diminuir os custos com a aquisição de nova cama, aumentar a quantidade de nutrientes na cama para ser utilizada como biofertilizante na agricultura e estabilizar ou diminuir o impacto ambiental com a produção de cama por ave produzida. No capítulo sobre biodigestão anaeróbia de cama de frangos, para cada lote de aves conduzidos foram realizadas duas avaliações de biodigestão anaeróbia, sendo 4 ensaios (camas de 1 a 4º reutilização) avaliados de 2 formas: as 4 camas foram avaliadas em diferentes épocas do ano e também avaliadas na mesma época... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective was to evaluate the effect of reuse of litter of four broiler breeding cycle on the broiler litter' production, the biogas' production and use of organic fertilizer for fertilization of maize. In the chapter on production of litter were evaluated four reuses of litter of broiler chickens reared in a commercial shed divided in 12 boxes belonging to Rei Frango Company in São Carlos - São Paulo - Brazil. To characterize the production of litter was assessed the amount of litter produced in dry matter (DM) and the coefficient of waste (CW), or the amount of waste per kg of live birds. In qualitative characteristics, were analyzed the levels of macro, micro and metals in the shell of peanuts and broiler litter. With the addition of new peanut shell, plus the increase of manure of the previous batch, there was an increase (P<0.05) in the production of litter (dry matter - DM). Thus, the increased CW according to the reuse of litter. But when assessing the cumulative CW, or the amount of waste per kilogram of body weight of accumulated lots of birds created, there was no difference (P>0.05). Overall, it was observed that with the reuse of the litter there was an increase (P<0.05) in the concentration of nutrients in litter. It follows that with the reuse of litter can be equal or lower cost for the purchase of new litter, increase the amount of nutrients in litter to be used as organic fertilizer in agriculture and keep or reduce the environmental impact to the production of litter by produced per bird. In the chapter on anaerobic digester with litter of broiler, for each batch of birds conducted two evaluations were made of anaerobic digester, and 4 trials (litters from 1 to 4 reuse) evaluated in 2 ways: the 4 litters were evaluated at different times of the year and also evaluated in the same season, totaling 8 tests. 24 digesters were used in batch, distributed... (Complete abstract click electronic access below) / Doutor
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Nitrato de cálcio como mitigador da emissão de metano em bovinos / Calcium Nitrate aiming at mitigation of methane emissions in cattleCassiano, Eduardo Cuelar Orlandi 25 August 2017 (has links)
Objetivou-se avaliar o uso de nitrato de cálcio (NC) na alimentação de ruminantes com vistas à mitigação da emissão de metano. Foram utilizadas quatro fêmeas de cada subespécie, Bos taurus taurus (Holandês) e vBos taurus indicus (Nelore), com peso médio inicial de 909,0 kg ± 72,0 e 387,0 kg ± 25,5, respectivamente, alimentadas com diferentes níveis de nitrato de cálcio na dieta (0%, 1%, 2% e 3%), sendo utilizado delineamento quadrado latino 4X4 replicado. O experimento teve duração de 4 períodos de 28 dias cada. Foram avaliados, a ingestão, excreção e digestibilidade de nutrientes, por meio de marcador externo dióxido de titânio, o comportamento ingestivo, com monitoramento visual por 24 horas, parâmetros sanguíneos, dinâmica ruminal, com esvaziamento total do rumen, contagem de protozoários, fermentação ruminal, pela técnica ex-situ, parâmetros urinários e balanço de nitrogênio, com coleta manual de urina tipo spot, e a biodigestão dos dejetos, por biodigestores do tipo batelada. Os taurinos apresentaram valores superiores para CMS, ingestão e digestibilidade de nutrientes e excreção de MS, PB, FDN, FDA, N, MO e EB, e inferiores para CMS em relação ao PV e PM. Os zebuínos apresentaram maiores taxas de ingestão, ruminação e mastigação de MS e FDN em min/kg, tendo valores inferiores para as mesmas taxas em kg/min. A genética e a dose de nitrato influenciaram as variáveis séricas, porém sem valores fora da normalidade. Quanto à dinâmica ruminal, os taurinos apresentaram valores absolutos superiores, e valores em relação ao PV e PM inferiores. Os zebuínos apresentaram maiores pH médio e mínimo e menos tempo de pH abaixo de 6,2, e maior contagem de protozoários. As concentrações de N-NH3, volume e produção de CH4 foram maiores para os zebuínos. Os taurinos apresentaram valores mais elevados para N microbiano (g/dia) e balanço de N retido (g/kg N ingerido), e menores valores para balanço de N nas fezes (g/kgN ingerido) e N microbiano (mg/kgPM.d-1). O aumento no nível de NC na dieta aumentou a digestibilidade de EE e ENN, tempo médio ruminando e taxa de mastigação de MS e FDN (min/kg), e diminuiu o CMS em relação ao PV e PM e excreção de MS, EE, ENN, MO e EB. A taxa de ingestão de MS e FDN (kg/min), a concentração de creatinina na urina (mg/kgPV), o tempo total comendo e balanço de nitrogênio amoniacal o rúmen sofreram efeito quadrático com a adição de NC na dieta. A porcentagem de FDN, PB e EE nos afluentes dos bidigestores sofreram influência da dose de nitrato na alimentação das vacas. Os biodigestores contendo os dejetos de taurinos tiveram os afluentes com maiores valores de FDN e FDA e menor teor de sólidos totais (ST), com menor volume de biogás e CH4 e menor relação de CH4/quantidade de fezes. Os taurinos apresentaram melhor aproveitamento do alimento, produzindo menos CH4, com menor rendimento verdadeiro de produção de metano nos biodigestores. A adição de NC afetou o consumo, digestibilidade e utilização do nitrogênio porém, sem afetar a produção de CH4 nem a eficiencia dos biodigestores. / The aim of the present study was evaluate the use of calcium nitrate in the feeding of ruminants to mitigate of methane. Four females cattle from each subspecies of cattle, Bos taurus taurus (Holstein) and Bos taurus indicus (Nellore), with initial average weight of 909,0 kg ± 72,0 e 387,0 kg ± 25,5, respectively, were used, and they were fed with distinct levels of calcium nitrate in the diet (0%, 1%, 2% e 3%) at four periods of 28 days each. Experimental design was composed by a replicated Latin square 4X4. Were avaluated: ingestion, excretion and digestibility of nutrients, by means of external marker titanium dioxide; the observation of behavior parameters during 24 hours; serum analysis; rumen content collection, aiming assessment of fermentation; protozoa count; ruminal fermentation by the ex-situ technique; manual urine collection for measurement of urinary compounds and nitrogen balance; and the anaerobic digestion of feces using batch digesters. Holsteins presented higher values for the DMI, ingestion and digestibility of the nutrients and excretion of DM, CP, NDF, ADF, N, OM e GE, and lower values for DMI at body weight (BW) and metabolic weight (MW) basis. Nellore cattle showed higher rates of ingestion, rumination and chewing of DM e NDF min/kg, having lower values for the same rates in kg/min. Serum variables were influenced by genetics and nitrate levels, but without values beyond normality. As rumen dynamics, Holsteins presented superior absolute values and inferior values when these parameters were calculated in BW and MW basis. The zebu cattle presented medium and minimum pH larger and less time pH below 6.2, having larger count for protozoa count. Nellore had higher concentrations for NH3, CH4 and production of CH4. Holstein presented higher values for microbial N (g/day) and N retained balance (g/kg N ingested) and lower values for N balance in feces (g/kgN ingested) and microbial N (mg/kgMW.d-1). The increase in the level of CN in the diet increased linearly the digestibility of EE and NNE, average time ruminating, chewing rate for DM and NDF (min/kg), and decreased the DMI in BW and MW basis and the excretion of DM, EE, NNE, OM and GE. The intake rate of DM and NDF kg/min, creatinine in urine (mg/kgBW), the total time eating and NH3 balance showed quadratic effect by increasing the addition of CN in the diet. The levels of nitrate on animal feed influenced the percentage of NDF, CP and EE in the batch digesters afluents. The biodigestors containing the taurine feces presented the highest values of NDF/ ADF affluent and lowest values for total solids (TS), lower volume of biogas and CH4 and lower ratio of CH4/amount of feces. Taurines presented better use of the feed, producing lesser CH4, and lower ultimate methane yield at batch digesters. The CN levels affected the intake, digestibility and nitrogen metabolism, however without affecting the production of CH4 or the batch digester efficiency.
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Digestão anaeróbia de resíduos de restaurantes: partida do reator e avaliação do biofertilizanteVelho, Douglas Ferreira 29 July 2016 (has links)
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Previous issue date: 2016-07-29 / Comitesinos - Comitê de Gerenciamento da Bacia Hidrográfica do Rio dos Sinos / FUNDEPE - Fundação Universitária para Desenvolvimento do Ensino e da Pesquisa / Petrobras - Petróleo Brasileiro S. A. / UNISINOS - Universidade do Vale do Rio dos Sinos / O crescente aumento na geração de resíduos sólidos urbanos, somado às formas inadequadas de tratamento e disposição contribuem de forma direta e significativa com a problemática ambiental. Diante deste cenário, se faz necessário o desenvolvimento de alternativas que permitam outros benefícios além da disposição final apropriada. A digestão anaeróbia é uma alternativa viável e economicamente interessante para tratamento da fração orgânica dos resíduos sólidos urbanos. Considerando que em nosso país a fração orgânica é predominante nos resíduos sólidos urbanos, correspondendo em média a mais de 40% na composição, ao mesmo tempo que reduz o volume de resíduos enviados para os aterros sanitários, o processo gera produtos como o biogás e biofertilizante para uso agrícola. Esta pesquisa teve como objetivo avaliar a tratabilidade da fração orgânica dos resíduos sólidos domésticos provenientes do preparo e pós consumo das refeições de um restaurante universitário em um reator operado por batelada e qualificar as características do biofertilizante gerado. Para atingir este objetivo, a pesquisa foi realizada em três etapas, sendo que na etapa inicial foram realizadas quatro bateladas nas quais foram analisadas a proporção adequada de resíduos e inóculo para partida do reator sem que ocorresse acidificação. A segunda etapa consistiu na realização de seis bateladas, nas quais foram monitorados os principais parâmetros de operação e a terceira etapa onde foram avaliados os parâmetros químicos, físicos e microbiológicos do biofertilizante gerado ao final dos ensaios da segunda etapa. Os resultados da primeira etapa apontaram que a proporção de 6:1 em termos de sólidos totais voláteis, sendo lodo proveniente de um reator UASB e resíduos sólidos putrescíveis respectivamente, apresentaram uma partida adequada do sistema, sem que ocorresse acidificação, com o pH variando entre 6,9 e 7,7. Na segunda fase o monitoramento dos principais parâmetros de operação permitiu que no decorrer dos ensaios a proporção em termos de STV fosse reduzida, chegando a 1:1 de inóculo e substrato respectivamente, na batelada 10, portanto permitindo o tratamento de uma quantidade maior de resíduos em relação aos ensaios iniciais. Os resultados obtidos no monitoramento apontaram que o pH manteve-se dentro da faixa considerada ideal entre 6,0 e 8,0, porém o período de vinte e dois dias adotado como tempo de retenção mostrou-se insuficiente para degradação e consequente remoção da matéria orgânica, sendo que apenas a batelada 10 mostrou-se eficiente na remoção de STV 8,1% e carbono orgânico total 33,5%. A análise física do biofertilizante gerado no final de cada ensaio apontou umidade acima do permitido pela legislação, sendo indicado apenas para uso via aspersão. Quimicamente o biofertilizante apresentou insuficiência de nitrogênio, evidenciada nas elevadas relações C:N iniciais e finais obtidas e carência de macronutrientes como fósforo cujos resultados ficaram abaixo de 1%, mínimo imposto pela legislação e potássio, elemento que não foi detectado na pelo equipamento utilizado. A qualidade sanitária do composto atendeu a legislação quanto a presença de ovos viáveis de helmintos, sendo que todos os ensaios apresentaram resultados inferiores a uma unidade/4g, porém apresentou resultados acima do limite estabelecido para coliformes termotolerantes. O teste de germinação confirmou a ausência da fitotoxidade dos produtos. / The increase in the generation of municipal solid waste, together with the inadequate forms of treatment and disposal contribute directly and significantly to the environmental problems. In this scenario, it is necessary to develop alternatives to other benefits in addition to the appropriate disposal. Anaerobic digestion is a viable alternative and economically interesting for the treatment of the organic fraction of municipal solid waste. Whereas in our country the organic fraction is predominant in urban solid waste, corresponding to an average of over 40% in the composition, at the same time reducing the volume of waste sent to landfills, the process generates products such as biogas and biofertilizers for agricultural use. This research aimed to evaluate the treatability of the organic fraction of household waste from the preparation and after consumption of meals from a university restaurant in a reactor operated by batch and qualify the characteristics of the generated biofertilizers. To achieve this goal, the research was conducted in three phases, with the initial phase were held four batches were analyzed in which the proportions of the waste and inoculum for starting the reactor without acidification occurred. The second stage consisted of six batches, which were monitored in the main operating parameters and the third stage where we evaluated the chemical, physical and microbiological biofertilizer generated at the end of the second stage trials. The first step results indicated that the ratio of 6: 1 in terms of total volatile solids, and sludge from a UASB reactor and solid waste putrescible respectively, showed a suitable starting system without occur acidification to pH between 6.9 and 7.7. In the second stage, the monitoring of key operating parameters allowed during the experiment the proportion in terms STV be reduced, reaching 1: 1 inoculum and substrate respectively in the batch 10, thus allowing treatment of a larger quantity of waste compared to the initial test. The results showed that monitoring the pH was maintained within the range considered optimal between 6.0 and 8.0, but the period twenty-two days adopted as the retention time was insufficient to degradation and subsequent removal of matter organic, and only the batch 10 was effective in removing STV 8.1% and 33.5% total organic carbon. Physical analysis of biofertilizers generated at the end of each test pointed humidity above those permitted by law and is intended only for use via spraying. Chemically biofertilizer showed nitrogen deficiency, evidenced in the high ratios C: Initial N and obtained final and lack of nutrients such as phosphorus whose results were below 1% minimum required by the legislation and potassium, an element that was not detected in the equipment used. The sanitary quality of the compound met the legislation for the presence of viable helminth eggs, and all tests showed lower results to a unit / 4G, but showed results above the limit for fecal coliforms. The germination test confirmed the absence of phytotoxicity of products.
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Modellering och styrning av flis till en sulfatkokare / Modelling and control of wooden chips to a sulphate digesterOhlsson, Staffan January 2005 (has links)
<p>At the Skoghall pappermill, sulphatepaper pulp is produced in a continuous digester originally from 1969. To be able to maintain a high level of production there is a need for a process with few disturbances. Variations in how well the wooden chips are packed in the digester is one form of disturbance. Today there are no available measurements on how well the chips are packed. Instead this is regarded as being constant. </p><p>The variation in the so called bulk density of the chips is mainly due to variations in the percentage with small dimensions. Chips are classified in relation to their size and one of the smallest classes is referred to as pin chips. These are believed to have a big impact on the bulk density. The amount of pin chips fluctuate more then the other classes, there by causing disturbances. </p><p>The Skoghall pappermill has invested in a ScanChip. This is an instrument that measures the dimensions of the chips optically. ScanChip presents figures on chip quality, including a measurement of the bulk density. However, it has been shown that this measurement is not valid for the Skoghall pappermill. By using data from ScanChip a model that predicts how well the chips are packed has been devised. This value is the bulk density divided by the basic density. The model has proved to yield good results, despite a relatively small amount of data. </p><p>A theoretical value of the amount of produced pulp has been computed based on the revolutions of the production screw that feeds chips into the digester. This value takes in consideration how well the chips are packed. The value has shown great similarities with the empirical measurements that are used today. A simulation during one month has shown that differences in the mixture of chips have effected the measurement of produced pulp with up to 7 ton/h. </p><p>Chips are stored in open pile storages before they are being used in the process of transforming them into pulp. Four screws are used to move chips from the piles to conveyer belts. It has been shown in work done previously, that the movement of the screws contributes to variations in the amount of pin chips measured by ScanChip. </p><p>During the work with this master’s thesis I have found that there are variations in the piles that make it difficult to predict the amount of pin chips accordingly. However by filtering the measurements of pin chips to remove these variations, the results are improved. A new way of controlling the movements of the screws was operational on the 10 of March and this improved the results. </p><p>The direction in which the screws are moving influence the speed of the screws, mainly in the pile with the so called sawmill chips. By changing the amount of chips that each screw puts out, the differences in speed have been reduced. The mixtures found in the two piles are not completely homogenous. There are a greater amount of pin chips in the northern parts compared with the southern parts. This could be an effect of the wind direction, and will still cause variations.</p>
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Energieffektivisering genom förvärmning av flis till kokare med sekundärvärme / Energy efficiency improvement by pre heating of woodchips to kraft digester with secondary heatIvarsson, Magnus January 2012 (has links)
The Swedish pulp and paper industry meets higher demand for energy efficiencyi mprovements with increasing energy prices and changes in the Swedish renewable energy certificate system. One action of energy efficiency improvement is by using secondary heat, that otherwise would have been treated as waste heat, for use in a system with lower temperature demands. The aim of this Master´s thesis is to identify possible secondary heat sources in a typical Swedish pulp and paper mill and to investigate what economic benefits the secondary heat will provide when being used for pre heating of wood chips to a kraft digester. The Master´s thesis focuses on three secondary heat sources; dry warm air, warm water and moisture saturated warm air located inside the pulp or paper mill. Two types of kraft digesters are simulated within this study, a typical Scandinavian digester and a modern twin vessel steam phase digester. Due to quality aspects and low temperature level drying is the drying technology with dry warm air rejected. Using warm water in direct contact with wood chips increases the quantity of water to the evaporation plant and thus reduced pulp or paper production and is therefore also rejected. The thesis nevertheless indicates a goodopportunity for further investigation of using moisture saturated warm air for preheating of wood chips. The humid air, from a drying machine or produced from secondary heat warm water, is used in a theoretical modified belt drier. Conservative assumptions regarding heat transfer and investment cost calculations yield a yearly net saving for a typical Swedish pulp mill at over 5 MSEK with a return on investment at 7years.
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Modellering och styrning av flis till en sulfatkokare / Modelling and control of wooden chips to a sulphate digesterOhlsson, Staffan January 2005 (has links)
At the Skoghall pappermill, sulphatepaper pulp is produced in a continuous digester originally from 1969. To be able to maintain a high level of production there is a need for a process with few disturbances. Variations in how well the wooden chips are packed in the digester is one form of disturbance. Today there are no available measurements on how well the chips are packed. Instead this is regarded as being constant. The variation in the so called bulk density of the chips is mainly due to variations in the percentage with small dimensions. Chips are classified in relation to their size and one of the smallest classes is referred to as pin chips. These are believed to have a big impact on the bulk density. The amount of pin chips fluctuate more then the other classes, there by causing disturbances. The Skoghall pappermill has invested in a ScanChip. This is an instrument that measures the dimensions of the chips optically. ScanChip presents figures on chip quality, including a measurement of the bulk density. However, it has been shown that this measurement is not valid for the Skoghall pappermill. By using data from ScanChip a model that predicts how well the chips are packed has been devised. This value is the bulk density divided by the basic density. The model has proved to yield good results, despite a relatively small amount of data. A theoretical value of the amount of produced pulp has been computed based on the revolutions of the production screw that feeds chips into the digester. This value takes in consideration how well the chips are packed. The value has shown great similarities with the empirical measurements that are used today. A simulation during one month has shown that differences in the mixture of chips have effected the measurement of produced pulp with up to 7 ton/h. Chips are stored in open pile storages before they are being used in the process of transforming them into pulp. Four screws are used to move chips from the piles to conveyer belts. It has been shown in work done previously, that the movement of the screws contributes to variations in the amount of pin chips measured by ScanChip. During the work with this master’s thesis I have found that there are variations in the piles that make it difficult to predict the amount of pin chips accordingly. However by filtering the measurements of pin chips to remove these variations, the results are improved. A new way of controlling the movements of the screws was operational on the 10 of March and this improved the results. The direction in which the screws are moving influence the speed of the screws, mainly in the pile with the so called sawmill chips. By changing the amount of chips that each screw puts out, the differences in speed have been reduced. The mixtures found in the two piles are not completely homogenous. There are a greater amount of pin chips in the northern parts compared with the southern parts. This could be an effect of the wind direction, and will still cause variations.
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Small-scale anaerobic digesters in Vietnam - development and challenges / Hầm ủ khí sinh học quy mô nhỏ ở Việt Nam - quá trình phát triển và các thách thứcNguyen, Vo Chau Ngan 06 August 2012 (has links) (PDF)
Small-scale anaerobic digesters, known as biogas plants, were applied as an optimal livestock waste treatment as well as biogas supply for cooking and lighting demand for small-scale farmers in Vietnam. Although the biogas technology was introduced for nearly 30 years, the number of the constructed biogas plants is still limited. The current development of biogas plants is far below the real demand on livestock waste treatment that has increased significantly. This paper gives a comprehensive overview on the biogas plant development in Vietnam and attempts to address the challenges and discuss appropriate solutions for the further biogas development. / Mô hình lên men yếm khí quy mô nhỏ (được biết với tên hầm ủ khí sinh học) đã được ứng dụng hiệu quả trong xử lý chất thải chăn nuôi cũng như cung cấp nguồn nhiên liệu phục vụ nhu cầu nấu ăn và thắp sáng cho các hộ chăn nuôi nhỏ ở Việt Nam. Mặc dù đã hiện diện gần 30 năm, nhưng số lượng hầm ủ khí sinh học vẫn còn hạn chế. Sự gia tăng số lượng hầm ủ khí sinh học chưa theo kịp với nhu cầu về xử lý chất thải chăn nuôi đang ngày càng gia tăng. Bài báo trình bày các chặng đường phát triển của hầm ủ khí sinh học tại Việt Nam, ghi nhận các thách thức trong việc nhân rộng hầm ủ khí sinh học trong thực tế và thảo luận một số giải pháp để phát triển công nghệ khí sinh học.
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