ABSTRACT:In this study it was evaluated the efficiency of the treatment of wet-processed coffee wastewater in upflow anaerobic sludge blanket (UASB) reactors in two stages, in bench scale, followed by post-treatment with activated sludge in batch. The first UASB reactor was submitted to an hydraulic retention time (HRT) of 6.2 d and organic loading rates (OLR) of 2.3 and 4.5g CODtotal (L d) -1 , and the second UASB reactor to HRT of 3.1 d with OLR of 0.4 and 1.4gThe average values of the affluent CODtotal increased from 13,891 to 27,926mg L -1 and the average efficiencies of removal of the CODtotal decreased from 95 to 91%, respectively, in the UASB reactors in two stages. The volumetric methane production increased from 0.274 to 0.323L CH 4 (L reactor d) -1 with increment in the OLR. The average concentrations of total phenols in the affluent were of 48 and 163mg L -1 , and the removal efficiencies in the UASB reactors in two stages of 92 and 90%, respectively, and increased to 97% with post-treatment. The average values of the removal efficiencies of total nitrogen and phosphorus were of 57 to 80% and 44 to 60%, respectively, in the UASB reactors in two stages and increased to 91 and 84% with the posttreatment.KEYWORDS: anaerobic digestion, methane, nitrogen, phosphorus, phenols. -1 , e as eficiências médias de remoção nos reatores UASB em dois estágios, de 92 e 90%, respectivamente, e aumentaram para 97% com o pós-tratamento. As eficiências médias de remoção de nitrogênio e fósforo total variaram, respectivamente, de 57 a 80% e de 44 a 60% nos reatores UASB em dois estágios e aumentaram para 91 e 84% com a inclusão do pós-tratamento. PALAVRAS-CHAVE: digestão anaeróbia, fenóis, fósforo, metano, nitrogênio.
DESEMPENHO DE REATORES UASB EM DOIS ESTÁGIOS SEGUIDOS DE PÓS-TRATAMENTO COM LODOS ATIVADOS EM BATELADA DE ÁGUAS RESIDUÁRIAS DO BENEFICIAMENTO DE CAFÉ POR