Orientador: Roberto Alves de Oliveira / Coorientador: Rose Maria Duda / Banca: Valderi Duarte Leite / Banca: Marcelo Bruno / Resumo: Neste trabalho avaliou-se os efeitos da suplementação de ferro, níquel e cobalto na produção de metano da vinhaça proveniente da destilação do etanol de cana-de-açúcar, em reatores anaeróbios de fluxo ascendente com manta de lodo (UASB, R1 e R2) termofílicos, em série. Para determinar os efeitos da adição do Fe, Ni e Co, o experimento foi realizado em 3 diferentes fases. Na fase I foi realizada a partida dos reatores UASB, R1 e R2, com o aumento gradativo da carga orgânica volumétrica (COV) até valores de 9,4 g DQOtotal (L d)-1. Nas fases II e III a COV variou entre 9,9 a 14,9 g DQOtotal (L d)-1, e a fase III distinguiu-se da fase II pela suplementação com Fe, Ni e Co, na vinhaça afluente. Para o R1, a suplementação com elementos traço induziu ao decréscimo de ácidos voláteis totais, de 1801 para 834 mg L-1, aumento na produção volumétrica de metano (PVM) em 101% e aumento na eficiência remoção de DQO para 53%. O Fe foi considerado o principal elemento traço por seus efeitos de precipitação com sulfeto e participação nas fases acetogênicas e metanogênicas da digestão anaeróbia. As relações Fe/DQO, Ni/DQO e Co/DQO de 12,59, 0,138 e 0,191 mg (g DQOremovida)-1, respectivamente, foram consideradas ideais para o R1, pois, possibilitaram as mais altas PVM atingindo até 1,4 L CH4 (L d)-1. No sistema (R1+R2), a adição de Fe, Ni e Co promoveu estabilidade operacional, e auxiliou na remoção de DQO, melhorando a eficiência total do sistema. Porém, não favoreceu a PVM, que manteve-se com... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this study was evaluated the effects of supplementation with iron, nickel and cobalt on vinasse in reactors upflow anaerobic sludge blanket (UASB, R1 and R2) thermophilic, in series. To determine the effects of the addition of trace elements, the experiment was conducted in 3 phases. During the first phase was characterized by the gradual increase of the organic loading rate (OLR) up to 9.4 g CODtotal (L d)-1, and start-up of system. In the phase II and III the OLR varied between 9.9 to 14.9 g CODtotal (L d)-1, the phase III distinguished of phase II only in trace element supplementation. For R1, trace element supplementation induced a decreased in total volatile acids, from 1801 to 834 mg L-1, increase in methane production rate (MPR) by 101% and increased in chemical oxygen demand (COD) removal efficiency to 53%. The Fe was considered the most relevant in the system due to its ability to precipitate with sulfide and participation in acetogenic and methanogenic phases of anaerobic digestion. The ratios Fe/COD, Ni/COD and Co/COD 12.59, 0.138, 0.191 mg g-1 CODremoved, respectively, they were considered ideal for R1, as they enabled as higher MPR reaching up to 1.4 L CH4 (L d)-1. For the system (R1+R2), the supplementation of Fe, Ni and Co promoted operational stability, and assisted in the removal of COD increasing the total efficiency of the system. However it did not favor the MPR, which remained on average of 0.571 L CH4 (L d)-1, and was similar to phase II, without addition of trace elements, with mean of 0.555 L CH4 (L d)-1. Therefore, it was verified that with the addition of trace elements, only R1 would be sufficient for the treatment of vinasse, but, if the treatment in chosen without the addition of trace elements, R2 would be essential for obtaining methane, but, without assurance of operational stability for the anaerobic digestion system. / Mestre

The aim of this study was to optimize methane production by investigating hydrothermal pretreatment of sugarcane bagasse impregnated with acid (H2SO4) and alkaline H2O2 using substrate (g kg-1) -inoculum (g kg-1) ratio of 1:2. Batch reactors were realized under mesophilic conditions (37 °C). A central composite design (CCD) involving three factors; temperature (°C), time (min), and chemical compound concentration (H2O2 (%v/v) and H2SO4 (%w/v)) was utilized to optimize hydrothermal pretreatment. Thirty-two hydrothermal pretreatments were conducted according to CCD. H2O2 assisted hydrothermal pretreatment resulted in higher solid recovery (93.13%), higher percent glucan increase (139.52%), and lower lignin recovery (76.48%) in pretreated solid fraction in comparison to H2SO4 impregnated hydrothermal pretreatment. In the latter case, lower solid yield (12.27%), glucan recovery (187.01%) and higher lignin recovery (358.85%) was recorded. Higher COD solubilization (25.20 g L-1), lower total phenolic (content 658.13 ppm), higher sulfate (7240 mg L-1), furfural (925.77-2216.47 mg L-1) and 5-hydroxymehtylfurfural (70.95-970.08 mg L-1) were observed in liquid hydrolysate of H2SO4 assisted hydrothermal pretreatment. While lower COD solubilization (17.75 mg L-1), higher total phenolic content (3005.63 ppm), lower concentration of furfural (0-56.91 mg L-1) and 5-hydroxymethylfurfural (2.56-56.60 mg L-1) was recorded with H2O2 assisted hydrothermal pretreatment. Concerning methane production for H2O2 assisted conditions, 5.59 Nmmol g-1 TVS (2% H2O2) to 13.49 Nmmol g-1 TVS (6% H2O2) was recorded. However, pretreatment with 7.36% H2O2 resulted in 14.43 Nmmol g-1 TVS, which was 118.16% higher comparing to untreated sugarcane bagasse (6.60 Nmmol g-1 TVS). Methanogenic inhibition was recorded for most of the H2SO4.pretreated reactor (1 – 3 %w/v H2SO4). Minimum CH4 production observed was 0.58 Nmmol g-1 TVS in pretreatment O-HSO (2% w/v H2SO4). Acetic acid was the predominant volatile fatty acid observed in digestion process of H2O2 treated batch reactor however was not recorded in H2SO4 treated batch reactors. Microbial community analysis indicated the prevalence of unclassified AUTHM297, Clostridium, and Treponema related genera in H2O2 treated reactors. Genera related aromatic compound degradation were identified and abundant in H2SO4 treated reactors. Methanolinea, Methanobacterium, and Methanosaeta were abundant methanogens in both pretreatments. Hydrogen peroxide assisted hydrothermal pretreatment was verified as a better choice for methane production comparing to sulfuric acid assisted hydrothermal pretreatment primarily on account of higher lignin solubilization, higher glucan recovery, and lower furanic compounds production. / O objetivo deste estudo foi otimizar a produção de metano investigando as condições do pré-tratamento hidrotérmico assistido do bagaço da cana de açúcar sob impregnação de ácido (H2SO4) e álcali (H2O2) utilizando-se a razão substrato (g kg-1) inóculo (g kg-1) de 1:2. Os reatores em batelada foram mantidos em condições mesofílicas (37 ºC). Para otimizar as condições de pré-tratamento hidrotérmico, o design de composto central rotacional (DCCR) foi realizado utilizando três fatores: temperatura (ºC), tempo (min) e concentração do composto químico (H2O2 (%v/v) e H2SO4 (% p/v)). Trinta e dois pré-tratamentos hidrotérmicos foram realizados de acordo com a concepção do DCCR. O pré-tratamento hidrotérmico assistido do bagaço, com H2O2 resultou em maior recuperação de sólidos (93,13%), elevado percentual de glicana (139,52%) e menor recuperação de lignina (76,48%) da fração sólida pré-tratada, se comparada aquele com H2SO4. Nesse último caso, observou-se menor rendimento de sólidos (12,27%) e glucanas (187,01%) e maior recuperação de lignina (358,85%). No líquido hidrolisado do pré-tratamento hidrotérmico assistido do bagaço com H2SO4 foi observada elevada solubilização de DQO (25,20 g L-1), menor teor de fenóis totais (658,13 mg L-1), elevado sulfato (7240 mg L-1), furfural (925,77 - 2216,47 mg L-1 e 5-hidroximetilfurfural (70,95 - 970,08 mg L-1). Enquanto, foi registrado menor solubilização de DQO (17,27 g L-1), maior teor de fenóis totais (3005,63 ppm), e menor concentração de furfural (0 - 56.91 mg L-1), 5-hidroximetilfurfural (2,56 - 50,60 mg L--1 com H2O2. Em relação ao a produção de metano nas condições com H2O2, observou-se 5.59 Nmmol g-1 STV (2%v/v H2O2) a 13.49 Nmmol g-1 STV (6%v/v H2O2). No tratamento com 7.36% de H2O2 observou-se 14,43 Nmmol g-1 STV que foi 118.16% maior se comparado com o bagaço não-tratado (6,60 Nmmol g-1 STV). Inibição metanogênica foi observada na maioria dos reatores pré-tratados com H2SO4 (1 – 3% p/v), e a produção mínima observada foi de 0.58 Nmmol g-1 TVS no pré-tratamento com 2% p/v de H2SO4. Ácido acético foi o principal ácido orgânico volátil observado somente no reatores por tratamento de H2O2. Por meio da A análise da comunidade microbiana, para o domínio Bacteria, foi observado prevalência dos gêneros AUTHM297, Clostridium e Treponema nos reatores cujo substrato foi pré-tratado com H2O2. Gêneros relacionados à degradação de compostos aromáticos foram identificados e estiveram em maior abundância nos reatores cujo substrato foi pré-tratado com H2SO4. Methanolinea, Methanobacterium, e Methanosaeta foram os microrganismos do domínio Archaea mais abundantes e identificados em ambos os pré-tratamentos. O pré-tratamento hidrotérmico assistido com H2O2 foi a melhor opção em relação ao H2SO4, devido a maior solubilização de lignina, maior recuperação de glucano e baixa produção de compostos furânicos.

O setor sucroalcooleiro vem ganhando cada vez mais destaque no agronegócio brasileiro. O Produto Interno Bruto (PIB) do setor na safra de 2015 gerou mais de US$113 bilhões ao longo de toda cadeia produtiva (UNICA, 2016). Esse período de ascensão é acompanhado de novos desafios e oportunidades, o que torna o setor um tema fértil para a pesquisa acadêmica, teórica e aplicada. Dada à pluralidade do setor que hoje extravasa seu nicho tradicional, álcool e açúcar, e atua cada vez mais intensamente nos setores energéticos, eletricidade e combustíveis renováveis, faz-se necessário a incorporação da nova dinâmica de produção que esses produtos trazem à realidade administrativa do setor. Assim, além de discutir teoria e metodologia correlatas à modelagem matemática empregada no auxilio à gestão do setor, esse trabalho visa contribuir com a literatura, incorporando e discutindo as novas possibilidades produtivas que a produção de biogás trás ao mix de produção tradicional. As principais ferramentas utilizadas nessa análise são a teoria de portfólios e o arcabouço teórico da otimização robusta. A partir dessas técnicas construiu-se um modelo de otimização onde se busca a minimização do risco para um dado retorno, princípio da teoria de portfólios, avaliando o risco com o CVaR, uma medida de risco mais adequada do que a tradicional variância. Construído esse modelo, analisa-se o papel do biogás, um produto ainda pouco usual nas usinas brasileiras, no portfólio produtivo de uma usina hipotética. Com base nesse modelo implementou-se as técnicas de otimização robusta com o intuito de aferir se os resultados verificados no modelo determinístico se mantém no caso robusto. / The sugarcane sector is gaining a huge prominence in the Brazilian agribusiness. The GDP of the sector in 2015 crop was over then US$ 113 billion along the entire production chain (UNICA, 2016). This auspicious period is accompanied by new challenges and opportunities, which makes the sector a hot field for academic research, theoretical and applied. Given the industry plurality which today goes beyond its traditional niche, alcohol and sugar, the sector is increasingly strongly its share in the energy sector, electricity and renewable fuels. Thus it is necessary to incorporate the new dynamic of production that these products bring to the administrative reality of the sector. Therefore, in addition to discussing theory and methodology related to the mathematical modeling used as a support to sector management, this work aims to contribute to the literature by incorporating and discussing the new production possibilities that biogas production brings to the traditional production mix. The main tools used in this analysis are the portfolio theory and the theoretical and applied framework of robust optimization. From these techniques it is built up an optimization model where one seeks to minimize risk for a given return, the principle of portfolio theory, assessing the risk with CVaR, a better measure of risk than traditional variance. Through this model, the role of biogas, an unusual product in the Brazilian plants, is analyzed considering a hypothetical plant. Based on this model it is implemented robust optimization techniques in order to assess whether the results observed in the deterministic model remains in the case robust.

The anaerobic biodegradability of food waste (FW), meat waste and FOG (fats, oils and greases) with municipal primary sewage sludge was assessed using a laboratory scale anaerobic digester and by ultimate sludge digestibility, at mesophilic conditions by varying the inoculum to feedstock ratio (1:2-1:10) and solids retention time (SRT). Preliminary analysis assessed the anaerobic digestion of food waste and meat at a biogas production over 30 days at 1000 mL and 1400 mL, respectively. The maximum methane yield was 0.18 m3/kg VS and 0.50 m3/kg VS for 1:10 in meat and FOG, respectively in 28 days with 56-61% volatile solids of destruction and first order methane generation rate of 0.15 d-1 for both meat and FOG. The optimal ratio for meat and FOG was determined to be beyond highest ratio tested (1:10), and longer SRT should be considered to investigate the impact of feedstock on methane yield. Preliminary modeling suggests that for one 1.74 MG digester, diverting just 0.6% of the food waste generated in one-third of Palm Beach County could produce enough methane to power 130-360 homes for one full month. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

Orientador: José Luz Silveira / Coorientador: Marcio Abud Marcelino / Banca: Agnelo Marotta Cassula / Banca: Celso Eduardo Tuna / Banca: José Rui Camargo / Banca: Sebastião Cardoso / Resumo: O presente trabalho trata do desenvolvimento, do processo construtivo, da implantação e da análise técnica, econômica e ambiental de uma miniETERA (miniestação ecoeficiente de tratamento de esgoto e reuso de águas), em PVC e concreto armado, associada a um sistema de cogeração de energia a biogás e a um sistema registrador e queimador de biogás para baixas vazões. A miniETERA é composta por três digestores anaeróbios de fluxo ascendente, em manto de lodo, do tipo UASB (upflow anaerobic slodge blancket) modificado, dispostos em série, formando cascata, seguido de um digestor híbrido aeróbio (com ar) e anóxio (sem ar na presença de nitrato). Para efeito do trabalho foi avaliada a eficiência dos reatores UASB, cuja redução média da DQO (demanda química de oxigênio) do efluente foi de 80,1%, sem a utilização de elementos eletromecânicos. O biogás produzido pelo sistema apresentou concentração média de 57,99% de metano no UASB I, devida à hidrólise, e de 80,45% de metano no UASB II, devida essencialmente à atividade metanogênica. O sistema compacto de cogeração de energia desenvolvido é composto por um motogerador de potência nominal de 5,5 kW a gasolina, convertido a biogás e/ou gás natural a baixa pressão (GNBP), acoplado a um trocador de calor gás/água, para a geração de energia elétrica e água quente. O cogerador compacto foi testado experimentalmente, utilizando biogás oriundo do tratamento anaeróbio de resíduo avícola, com uma porcentagem de 60% de metano; obteve-se uma potência útil de 2,6 kW e, no caso do uso de GNBP, a partir de GNV (gás natural veicular) despressurizado, obteve-se uma potência útil de 4,2 kW. O reuso de água foi feito por meio de sistema de fertirrigação de um bosque em 12 formação, com o efluente tratado. A análise técnica e econômica... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This paper deals with the development of the constructive process, and deployment of technical, economic and environmental dimensions of a EMSTWR (ecoefficient ministation of sewage treatment and water reuse), PVC and concrete, coupled with a cogeneration system to biogas energy system and a recorder and burner biogas for low flow. The Miniet is composed of two anaerobic digesters in upflow sludge blanket, UASB type (Upflow Anaerobic slodge blancket) modified, arranged in series forming cascade, followed by an aerobic digester Hybrid (air) and anóxio (no air in the presence nitrate) for the purpose of this study was to evaluate the efficiency of UASB reactors, whose average reduction of COD (chemical oxygen demand) of the effluent was 80.1% without the use of electromechanical components. The biogas produced by the system showed an average concentration of 57.99% methane in UASB I, due to hydrolysis, and 80.454% methane in UASB II, mainly due to methanogenic activity. The compact cogeneration power developed is composed of a motogenerator rated at 5.5 kW gasoline, or converted to biogas and natural gas at low pressure (NGLP) coupled to a heat exchanger gas / water for the generation electricity and warm water. The compact cogenerator was tested experimentally using biogas originating from anaerobic treatment of poultry manure, with a percentage of 60% methane, we obtained an output of 2.6 kW, and in case of using NGLP from NGV (Natural Gas Vehicle) depressurized, we obtained an output of 4.2 kW. Reuse of water was done through fertigation system in formation of a forest, with the treated effluent. A technical and economic analysis of EMSTWR compared with traditional systems of 14 sewage treatment, was interesting from the standpoint of environmental, energy and economic... (Complete abstract click electronic access below) / Doutor

Orientador: Jorge de Lucas Junior / Banca: Mônica Sarolli Silva de Mendonca Costa / Banca: Mauro dal Secco Oliveira / Resumo: O experimento foi realizado na Faculdade de Ciências Agrárias e Veterinárias da UNESP de Jaboticabal, objetivando-se avaliar os benefícios da utilização de dois ativadores biológicos comerciais, Microsource "S"® e uma mistura de microrganismos e enzimas (B. subtilis, B. firmus, B. licheniformis, lipase, protease e lactase) na digestão anaeróbia de dejetos de bovino de corte e de dejetos suínos. Na primeira parte do experimento foram testadas duas doses de cada produto com os dois dejetos, utilizando 30 digestores batelada, a fim de determinar qual produto e em qual dose proporcionaria o maior aumento na produção específica de biogás (PEB). O tempo de retenção hidráulica (TRH) dos dejetos bovinos nos digestores batelada foi de 150 dias e dos suínos 100 dias. Periodicamente foram calculados o volume de biogás produzido e os teores de CH4 e CO2. Ao término da primeira fase foi escolhido, para a segunda fase do experimento, o produto Microsource "S" ® na dose de 500g/t de dejeto. Na segunda fase do experimento foram utilizados 12 biodigestores contínuos, com TRH de 30 dias, a fim de testar o tratamento escolhido em um processo anaeróbio de tipo contínuo. Nesta fase foram repetidas as análises supracitadas com maior frequência, a fim de se monitorar a evolução do processo. A análise da variância, efetuada com o software SAS®, apontou como o Microsource "S"®, aplicado a dejetos de bovinos de corte, na dose de 500g por tonelada de substrato, proporciona um aumento de 15,03% na PEB / Abstract: A trial was carried out at the Faculty of Agriculture and Veterinary Sciences, UNESP, Jaboticabal, aiming to evaluate the benefits of using two commercial biological activators, Microsource "S"® and a mixture of enzymes and microorganisms (B. subtilis, B. firmus, B. licheniformis, lipase, protease e lactase) in the anaerobic digestion of beef cattle and swine manure. During the first stage of the experiment, two doses of each product have been tested with the two manures in order to determine which dose of which product provide the highest increase of specific biogas production, using 30 batch digesters. The hydraulic retention time have been of 150 days for the beef cattle manure and 100 days for the swine manure. Periodically produced volume of biogas and contents of CH4 and CO2 have been calculated. At the end of the first stage has been selected for the second phase of the experiment the product Microsource "S"® at a dose of 500g/t of manure. In the second stage of the experiment 12 anaerobic digesters have been used to test the chosen treatment in a continuous anaerobic process with a 30 days hydraulic retention time. At this stage the tests were repeated more often above, in order to monitor the progress of the process. The analysis of variance, performed with SAS® software, pointed out Microsource "S"®, applied to beef cattle at a dose of 500 g per ton of substrate, provides an increase of 15,03% in biogas specific production / Mestre

Modern society depends on fossil fuels to fulfill the increasing energy demand, which could cause further damages in the environment. Therefore, it is mandatory to develop technologies for the production of efficient alternative renewable energy sources, like biofuels. Agricultural waste streams, such as wheat straw, produced in larger amount can be utilized for these purposes, and can be used as raw materials for both ethanol and biogas production. However, the compact structure of lignocelluloses present in these materials makes their biological degradation difficult.In order to enhance the biogas production, wheat straw milled to 2mm size was pretreated with N-methylmorpholine-N-oxide (NMMO) at 90°C for 7-30 hours in this study. 90°C was applied as treatment temperature for the treatment to be able to investigate if the district heating system could be utilized in the treatment process in the future. The effects of the different pretreatment conditions were then evaluated by running batch anaerobic digestion assays for 45 days at 55°C.The best result was achieved after 7h treatment, leading to 0.47 Nm3/kg VS of straw methane production, corresponding to an increase by 47% compared to methane production obtained for the untreated straw.Furthermore, it was possible to recover up to 91.33% of the straw after the NMMO pretreatment. There were no significant changes in the chemical composition of the straw caused by the treatment, however structural analyses, like FTIR for the determination of crystallinity and and Simon Staining for the determination of porosity of the material showed that the crytallinity decreased, while the porosity increased as results of the treatment.Soaking in water for 72h prior to NMMO treatment was also applied to see whether it can improve the diffusion of NMMO into the material, but without success, due to the dilution of the treatment chemical caused by the soaking. The findings made during the experimental stage indicated that it is possible to run the NMMO pretreatment at an industrial temperature, further evaluation for the economical feasibility of this treatment method is however needed in the future. / Program: MSc in Resource Recovery - Industrial Biotechnology

Uppgiften för examensarbetet har varit att göra en bestämning av ammoniumhalten ibiogasslurry med hjälp av jonkromatografi. Resultatet från analysen har sedan jämförtsstatistiskt för att bland annat se repeterbarheten för metoden. Metoden har även jämförts medden spektrofotometriska metoden som finns på Sobacken, så kallad Langemetoden.Ammoniumhalten är en parameter som påverkar biogasbildningen i rötkammaren och det ärdärför viktigt att denna hålls låg.Jonkromatografi är en separtionsmetod som bygger på jonbyteskromatografi. En separationsker i en kolonn innehållande en stationär fas och genom den flödar den mobila fasen ochäven provet. Den stationära fasen och eleuenten har olika laddningar, för katjonkolonnen ärden stationära fasen negativ och den mobila positiv. Jonkromatografens katjonkolonn kräveratt provet är fritt från alkoholer och partiklar större än 0,45 μm. pH ska även ligga mellan 2,5och 3,5 och provet ska spädas med eluenten. Provet har därför beretts i ett antal steg;centrifugering, surgörning samt filtrering. Eventuella alkoholer har testats genom att köraprovet på HPLC och jämfört med en standard innehållande metanol, etanol, propanol ochbutanol. Resultatet från HPLCn gav att provet var fritt från alkoholer och kunde då analyseraspå jonkromatografen. Spädning hundra gånger krävdes för att en god separation skulle skeoch kromatogrammet skulle kunna integreras på ett bra sätt. För att få ut koncentrationengjorde en standardkurva för ammoniumjoner.Resultatet från mätningarna har gett att repeterbarheten för jonkromatografen är god.Jämförelse mellan jonkromatografin och Langemetoden visade att det fanns en signifikantskillnad mellan mätningarna, där jonkromatografin endast ger ca 65 % av värdet frånLangemetoden. En test visade att Langemetoden reagerar med aminosyrakväve, intekvantitativt, men så mycket att det skulle kunna förklara skillnaden mellan metoderna.Resultatet pekar på att de höga koncentrationerna av ammoniumkväve som man uppmäter vidSobacken, i verkligheten är klart lägre. Vidare undersökningar krävs för att klarlägga dettanoggrannare.

According to national and international policies in order to protect environment regarding renewable sources of energy, biogas is one of the best alternative to reduce waste and pollution and getting energy. Biogas is the gas that is produced by some kinds of microorganisms in anaerobic condition from organic waste treatment. Technology of biogas plants is varies and there is no standard procedure that is applicable worldwide. Methane (biogas), which is produced from wastes and it is known widely since 1973. By organic waste degradation methane is produced and waste volume will be reduced. Some surveys prove that during anaerobic digestion only 50% of organic matter is degraded. Anaerobic degradation has some steps that are hydrolysis, acidogenesis, acetogenesis and methanogenesis. Since hydrolysis is rate-limited step it can be improved by some pretreatment and some action like improving monitoring system can show that the efficiency of biogas will increase. There are three main pretreatment methods. During this study digestate sludge from different waste treatment plants were pretreated. First experience was pretreating digestate sludge from Sobacken, Falköping, Västerås by Enzyme Addition (Cellolase) and the measuring of biogas (methane) has done by Gas Chromatograph (GC). Second experience was pretreating digestate sludge by Acid (Sulfuric acid). The data of those measurements are shown that the amount of biogas was increased two times in the case of Västerås by enzyme addition, which is about 70% of theoretical expectation of this pretreatment and pretreating digestate sludge of Sobacken by acid pretreatment could increase the amount of biogas two times as well that was about 60% of theoretical estimation. By proper gas chromatograph and choosing one kind of waste and pretreating that by just one kind of pretreatment in each experience and following the results and going further the biogas efficiency will increase significantly because still 50% organic matter is inside the digester. / Uppsatsnivå: D

A decomposição de resíduos sólidos urbanos em aterros sanitários é uma fonte importante de metano para a atmosfera. Este gás tem uma contribuição significativamente maior que o dióxido de carbono na retenção do calor na atmosfera e no consequente aquecimento global (efeito estufa). A oxidação biológica do metano nos sistemas de cobertura de aterros é uma alternativa para a diminuição das emissões fugitivas deste gás. Esse processo ocorre pela atividade microbiana em ambientes nos quais estão disponíveis metano, oxigênio e bactérias metanotróficas. O potencial de oxidação de metano nas camadas de cobertura de aterros de resíduos sólidos urbanos (RSU) pode ser favorecido pela criação de condições ambientais propícias. Este trabalho propõe uma metodologia para monitoramento e quantificação da oxidação do metano, a fim de avaliar o desempenho de diferentes materiais para coberturas oxidativas, levando-se em conta os aspectos climáticos. Foram avaliados dois sistemas de coberturas por meio de biofiltros. Estes biofiltros foram instalados no aterro DELTA A da cidade de Campinas, utilizando como fonte de metano um poço de captação de biogás do aterro. Foram utilizados dois tipos de materiais, um com resíduo de construção e demolição (RCD) e outro com areia natural, os dois misturados a composto orgânico maduro. Foram monitorados ao longo de 20 meses os perfis de concentração dos gases (metano, dióxido de carbono e oxigênio) e os fatores meteorológicos (pressão atmosférica, temperatura e precipitação). O estudo demonstrou que as duas misturas utilizadas podem oxidar o metano e que o fluxo de metano é controlado pela permeabilidade ao gás e este fluxo condiciona o percentual de oxidação. O valor máximo de oxidação obtido foi de cerca de 10 kg de CH4/m²dia. O estudo propõe, ainda, uma metodologia para quantificação da oxidação do metano que toma como base as medições de concentração ao longo do perfil da camada e a vazão oxidada. / The decomposition of solid waste in landfills is a major source of methane to the atmosphere. This gas contributes more than carbon dioxide to heat trapping in the atmosphere and to the consequent global warming (greenhouse effect). The biological oxidation of methane in landfill cover systems is an alternative to reduce fugitive gas emissions. This process occurs by microbial activity in environments where methane, oxygen and methanotrophic bacteria are available. The methane oxidation in urban landfill cover systems can be improved by the creation of favorable environment conditions. A methodology for monitoring and quantification of methane oxidation is proposed, to evaluate the performance of different materials for oxidative cover, taking into account the climatic aspects. We evaluated two biofilter cover systems installed at Delta A landfill located in the city of Campinas (SP). The gas collection system well was used as methane source. Two different materials were tested: (1) construction and demolition waste and (2) natural quartz sand, both mixed with organic mature compost. The methane, carbon dioxide and oxygen concentration profiles and meteorological factors (atmospheric pressure, temperature and precipitation) were monitored over 20 months. The two materials were capable of oxidizing methane. Methane oxidation was affected by flow rate through the cover system, and therefore by the material gas permeability. The maximum methane oxidation rate was approximately 10 kg CH4/m².day. A methodology is proposed for quantifying methane oxidation based on measurements of methane concentration and flow rate in the upper part of the biofilter.