Produção de metano em AnSBBR tratando vinhaça em condição termofílica

Abstract

The thermophilic anaerobic digestion of wastewater that are generated at high temperatures appers as an option for the environmental pollution control and bioenergy production. Thus, this study investigate a anaerobic reactor containing immobilized biomass and mechanical stirrer operate in sequential batch or feed batch treating vinasse-based wastewater for methane production. It was analyzed the effects on reactor performance of increasing the applied volumetric organic load (AVOL) and modifying the feeding strategy. The total volume of liquid was 2,3 L, in which 1,3 L of residual volume and 1,0 L of wastewater to be treated per cycle, keeping constant the temperature (55 ºCthermophilic range), the cycle length (8 hours) and the stirred velocity (100 rpm). At first it was realizes the biomass adaption, then it was analyzed the applied volumetric organic load (6,5-25,9 gDQO.L-1 .d-1) increasing the influent concentration and after the feeding strategy was modified. In the AVOL increasing were achieved higher molar productivity of methane (304 molCH4.m-3 .d-1) and volumetric productivity (6828 mL-CNTP CH4.L-1 .d-1) at AVOL of 25,9 gDQO.L-1 .d-1 , and molar yield of methane per organic matter removed close to the theoretical value (15,6 mmolCH4.gDQO-1) and removal efficiency of organic matter in terms of DQO between 75-80% for all conditions above AVOL of 14 gDQO.L-1 .d-1. In the stage of feeding strategy change, the methane molar and volumetric productivity were 351,9 molCH4.m-3 .d-1 and 7888 mLCH4.L-1 .d-1 , receptively, and the yield methane production per removal organic matter close to the theoretical value. The energy production were 25,1 MW and 30,3 MW in the batch and fed batch conditions, respectively. The kinetic model allowed known of AVOL and feeding strategy influence under the reactor performance to methane generation, analyzing the reaction coefficient of the compounds consume/production involved in the metabolic rote.