Series batch experiments were made to investigate the influences of pH and temperature on the activity of acidogenus and acidogenus in glucose-degrading bacteria cultured in an UASB(up-flow anaerobic sludge blanket) reactor for glucose fermentation and hydrogen production. The bacteria exhibited different capability to recover to produce hydrogen at different initial pH and temperature. Hydrogen production, VFA production, COD removal and COD balance were measured at different pH and 20, 37 ℃ respectively with the same glucose and VSS in vials. Results showed that there are different influences on the activity of acidogenic bacteria at varied pH and result in a variety of amount of hydrogen production, specific hydrogen production and VFA production, etc. Through the present study, when nonmalized to the weight of VSS, a maximal biogas and hydrogen production of 1 717 1 ml/g and 870 0 ml/g were obtained when pH equals 9 at 37 ℃ and 679 00 ml/g of biogas, 246 35 ml/g of hydrogen were also got when pH equals 5 at 20 ℃ respectively. The maximal specific hydrogen production (SHA) was 116 56 ml/h,g around 8 of pH value at 37 ℃ and 6 46 ml/h,g around 4 of pH value at 20 ℃, which were obtained by calculating the slope of the accumulated hydrogen gas via time. Butyric acid fermentation was important for hydrogen production. Large quantity of unknown COD was found in the vials when a small quantity of bio-gas was produced, but relative less unknown COD was determined when there was large quantity of hydrogen produced. This revealed a better engineering foreground for application of hydrogen bio-production.
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