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ABSTRACT. The increasing deployment of biodigesters for the treatment of waste on farms and the use of the biogas generated in the production of energy have highlighted the need for knowing the influence of this fuel on internal combustion engines. This study aimed to analyze the influence of filtrated biogas on lubricant oil contamination and degradation, as well as on engine wear and corrosion. Lubricant oil samples were collected every 75 engine operating hours (EOH) and then correlated between each other and with a sample of new oil, determining the elements present in the biogas that contribute to lubricant oil contamination and degradation, as well as lubricant oil performance in the course of EOH and engine wear. The results demonstrate that hydrogen sulfide affects the performance of the lubricant oil and engine wear. Among the metals, we observed that the copper concentration exceeded the maximum limit recommended in the literature. As for the additives, the variation in concentrations of magnesium impacted on lubricant performance. By monitoring lubricant oil quality were able to extend the engine oil change interval of this study by 50%, what resulted in a savings of 33.3% in the cost of lubricant per hour worked.Keywords: contaminants, biogas, biodigester, biomethane, corrosion.Análise da contaminação e degradação do óleo lubrificante e desgaste de um motor ottolizado alimentado por biogás RESUMO. A crescente implantação de biodigestores para tratamento de resíduos nas propriedades rurais e a utilização do biogás gerado na produção de energia mecânica evidenciaram a necessidade de conhecimento da influência de utilização deste combustível nos motores de combustão interna. Este trabalho teve como objetivo analisar a influência da utilização do biogás filtrado na contaminação e degradação do óleo lubrificante, desgaste e corrosão do motor. Amostras de óleo lubrificante foram coletadas a cada 75 hM (horas de funcionamento do motor), e após correlacionadas dentre elas e com uma amostra de óleo novo, determinando os elementos presentes no biogás que contribuem para a contaminação e degradação do óleo lubrificante, como também o desempenho do lubrificante no decorrer das hM e o desgaste do motor. Os resultados demostraram que o gás sulfídrico influencia no desempenho do óleo lubrificante e no desgaste do motor. Dentre os metais, foi identificado que a concentração de cobre excedeu o máximo recomendado pela literatura, e a elevação da sua concentração teve relação com a elevação de chumbo e estanho, principalmente após as 375 hM. Em relação aos aditivos, foi a variação das concentrações de magnésio que impactou no desempenho do lubrificante. Por meio do monitoramento da qualidade do lubrificante é possível estender o intervalo de troca de óleo do motor do presente estudo em 50%, resultando em uma economia de 33,3% no custo do lubrificante por hora trabalhada.

ABSTRACT. The addition of different concentrations of crude glycerin, associated with cattle manure, on the volumetric production of biogas is analyzed. Different concentrations of crude glycerin (2, 4 and 6% m m -1 ) were added as supplement in anaerobic co-digestion of dairy cattle waste, in laboratory batch biodigesters (3.5 L usable volume). The biodigesters were operated under mesophilic conditions (30ºC), with 30-day hydraulic retention time (HRT). Total solids (TS), volatile solids (VS) and chemical oxygen demand (COD) were analyzed to determine the efficiency of the process in the removal of organic matter and its effect on biogas production. The addition of 4% glycerin provided a larger production of biogas, approximately 9.307 mL. The efficiency in COD removal decreased in treatments with glycerin, with highest reduction (68%) in the control treatment. There was a 90 and 118% increase respectively for Gli4 and Gli6% treatments. VS reductions Gly 0, Gly 2, Gly 4 and Gly 6% treatments were 18.17, 61.60, 24.36 and 44.83%, for the respective treatments.Keywords: bio-digestion, cattle manure, biogas, crude glycerin, biodiesel.Avaliação da codigestão de glicerina associada a esterco bovino para produção de biogás no Estado do Paraná, Brasil RESUMO. O objetivo do trabalho foi avaliar o efeito da adição de diferentes concentrações de glicerina bruta associada com esterco bovino, sobre a produção volumétrica de biogás. A adição de diferentes concentrações de glicerina bruta (2, 4 e 6% m m -1 ) foi utilizada como suplemento na codigestão anaeróbia de dejetos bovinos de leite, em biodigestores laboratoriais de batelada (3,5 L de volume útil). Os biodigestores foram operados em condições mesofílicas (30ºC), com tempo de retenção hidráulica (TRH) de 30 dias. Foram analisados os sólidos totais (ST), sólidos voláteis (SV) e demanda química de oxigênio (DQO), a fim de determinar a eficiência do processo na remoção da matéria orgânica e seu efeito na produção de biogás. A adição de 4% de glicerina resultou na maior produção de biogás, cerca de 9,307 mL. A eficiência na remoção de DQO diminuiu nos tratamentos com adição de glicerina, sendo a maior redução no tratamento controle, de 68%. Nos demais tratamentos houve um aumento de 90 e 118% para os tratamentos Gli 4 e Gli 6% respectivamente. As reduções de SV para os tratamentos Gli 0, Gli 2, Gli 4 e Gli 6%, foram de 18,17, 61,60, 24,36 e de 44,83%, para os respectivos tratamentos.Palavras-chave: biodigestão, dejetos bovinos, biogás, glicerina bruta, biodiesel.

This study aimed to evaluate the crude glycerol efficiency, from biodiesel production, biogas production with co-digestion of swine manure. The process was conducted with several concentrations of glycerol 0, 5, 10, 20, 30 and 40% (w/w) and swine manure with a concentration of 20, 40 and 60% (w/w) with pH 7.2 and 35°C. The fermentation periods were 21 and 30 days. Fifty ml of micro-reactors were used airtight coupled to a 10 ml syringe best condition to evaluate the production of biogas. Analysis was also performed to evaluate total solids reduction of solids mass in proposed treatments. Using a digestion system on a laboratory scale, is constituted by a 20 L reactor total volume, a gas meter and a reservoir for storage thereof, biogas production was evaluated for the sample with 5% of glycerol and the control sample (0% glycerol). With the aid of a gas chromatograph analyzed the methane content thereof. It was observed that the amount of swine manure has great influence on the production of biogas and the concentration in the sample yield was better with 60%. The crude glycerol together to swine manure at a rate of 5% w/w can be used as a supplement in anaerobic digestion, providing a significant increase in the production of biogas in its content of methane and removal of total solids. Moreover, it has been found that concentrations of 20, 30 and 40% (w/w) of glycerol were inhibitory at all studies, difficulties occur and little production of biogas. Chromatographic analysis of the sample with 5% glycerol was satisfactory in relation to methane content, showing 58.87% of CH4 in the biogas.