Efeito da adição de óleo e lipase sobre a biodigestão anaeróbia de dejetos suínos

Abstract

We evaluated the efficiency of co-anaerobic digestion of swine manure with increasing addition levels of oil discharge (8, 12, 16 and 20g/kg substrate), lipase (1, 2 and 3g/kg substrate). The wastes were from finishing pigs from a commercial farm and were collected by scraping the stalls. The oil was obtained in disposing of frying a commercial pastry from Dourados-MS. The lipase used was Pancreatin 3FN. The slurry was mixed with the water and oil disposal lipase concentrations being composed predetermined substrates and the supplied batch digesters bench with 5 kg of substrate. The influence of the oil levels and enzyme was verified by means of changes in physical-chemical and microbiological proportionate to the substrates beyond the biogas production and the potential production per kg of substrate per kg of manure per kg TS and VS added and reduced. The results demonstrate that no influence of the additions of oil and lipase on reductions TS VS effluent pH where there was a negative linear effects. The reduction in COD showed a quadratic effect in relation to additions of oil likely caused by organic overload which provided a reduction of biodegradability treatment with 20g of oil per kg of substrate. The reductions in TC and TTC were higher in treatments with more adding oil and lipase. Biogas production showed a negative correlation with the additions of lipase, and these yielded negative linear effect on the production of biogas per kg of waste per kg per kg of TS and VS added. The maximum potential production of biogas obtained was 77,1 liters per kg of manure added to the digester. The largest potential of biogas production in most cases occurred in treatments with minor additions of oil and lipase (8g oil and 1g of lipase / kg of substrate). The concentrations of P and K in the substrate showed a quadratic effect in relation to additions of lipase, when in larger quantities (3g/kg substrate).