Biohydrogen production in AnSBBR in fed-batch from starch effluent: Influence of organic load

Abstract

The hydrogen is a fuel with a high energy density. Studies have sought to verify the potential of different residues and configurations of reactors in the production of biohydrogen. This study evaluated the influence of the organic loading rate on the production of biohydrogen from cassava starch wastewater (CSW) in anaerobic sequencing batch biofilm reactors (AnSBBR) operated in a fed-batch. In the tests, the organic loading rates of 9.0; 13.5 and 18.0 gCT L-1 d-1 were used, at cycle times (CT) of 4; 4 and 2 h (tests I, II and III, respectively). The reactor was inoculated with sludge from a pilot anaerobic reactor used in the treatment of CSW, heat treated (heated at 90°C for 15 min). With the increase of the organic load (condition I to II) with the same cycle time (CT: 4 h), there were increases in the hydrogen molar productivity (PrM) and hydrogen yield in relation to applied total carbohydrate (RMCA) and removed (RMCR). However, with the increase in the organic loading rate in which the CT was reduced from 4 to 2 h (condition II to III), there was a decrease in PrM and RMCA and RMCR. The best performance of the reactor was verified in condition II (organic loading rate: 13.5 gTC L-1 d-1; CT: 4 h), in which the PrM was 35.8 molH2 m-3 d-1 and RMCA and RMCR were 2.24 and 3.67 molH2 kgTC-1, respectively.