TRATAMENTO DE EFLUENTE DE FECULARIA EM REATOR ANAEROBIO DE MISTURA COMPLETA COM CONTROLE DE TEMPERATURA

Abstract

Cassava starch industries generate effluents that, stabilized in ponds, waste the potential for biogas generation and pollute the environment. Signaling to change this reality, the research was developed in a prototype of a single-phase anaerobic reactor of complete mixture, feeding with cassava starch effluent. The 408 L anaerobic biodigester prototype was developed by Biokohler® with agitation and temperature control mechanisms, as well as operated in continuous feeding mode. The following parameters were verified: solids, pH, oxygen chemistry (COD), volatile acidity (AV), total alkalinity (AT), volatile acidity and total alkalinity (AV/AT), total reducing sugars (ART) and soluble (Arts). After the start of the anaerobic digestion process, the organic load in the biodigester was gradually elevated, respecting the acceptable limits representing the AV/AT and pH ratios. The prototype anaerobic biodigester was efficient in removing organic matter from the manipueira, in the order of 80% in COD, 79% in ART and 87% for Arts. The average specific yield of biomethane obtained in the prototype biodigester was 0.422 LCH4 gDQOc -1 , 1.58 LCH4 gSVc -1 , 0.530 CH4 gARTc -1 and 0.94 CH4 gARTsc -1 . The prototype anaerobic biodigester was efficient in removing organic matter from COD, SV and ART. However, some steps were necessary to find the adequate organic load of feed represented by stability based on the AV/AT ratio, which presented the average value of 0.34.