Biohydrogen production by fermentative process in continuous stirred-tank reactor

Hydrogen production by anaerobic mixed culture was studied at 35 degrees C and pH5.5 in a continuous-stirred tank reactor (CSTR) using glucose as a carbon source. The variations of hydraulic retention time (HRT) affected on hydrogen production were investigated. The biogas composition, hydrogen production rate, and hydrogen yield increased when hydraulic retention time was decreased. The biogas contained 38.5 - 73.9% hydrogen and the hydrogen production rate ranged from 0.50 to 3.34 LH2/L/d. Furthermore, the hydrogen yield increased from 0.62 to 1.24 mol-H-2/mol-glucose. The, morphology of hydrogenproducing bacteria was composed of diliplobacilli The microbial communities of anaerobic mixed culture were also investigated by the restriction fragment length polymorphism analysis. Clostridia and Bacilli were predominant populations in the continuous stirred-tank reactor.