AnSBBR Operated in Batch and Fed-Batch Modes Applied to Biohydrogen Production Treating Lactose-Based Wastewater

Abstract

An assessment was made of a batch and fed-batch AnSBBR applied to the production of biohydrogen by treating lactose-based wastewater. The reactor of 6.0 L was subjected to different applied volumetric organic loads (AVOL) of 9.3 to 27.8 gCOD.L-1.d-1, obtained by varying influent concentration (3600 and 5400 mgCOD.L-1) and cycle lengths (4, 3 and 2 h) at 30 °C. The feeding time corresponded to 2-8% (10 min) and 50% of total cycle length for batch and fed-batch operation, respectively. For 9.3 gCOD.L-1.d-1 the fed-batch AnSBBR was operated at 30 and 42 °C. Organic material removal efficiency, in terms of COD, was 16 to 20%, and in terms of carbohydrates, 96 to 99%. The highest value of hydrogen molar yield per removed organic load (MYRLS,n) obtained was 1.87 molH2.molLAC-1 (9.3 gCOD.L-1.d-1) for fed-batch operation The highest daily hydrogen molar productivity (MPr) results, obtained for the highest applied organic load, were 63.2 and 70.4 molH2.L-1.d-1, for batch and fed-batch operation, respectively. The values of MPr and MYRLS,n decreased when temperature was increased. For practically all biohydrogen production indicators, the fed-batch operated AnSBBR yielded better results. © 2015 Nova Science Publishers, Inc.