Comparative performance of fhermophilic and mesophilic anaerobic hydrogen fermentation

摘要

This study is to compare performance of hydrogen fermentation between two anaerobic hydrogen fermentation bioreactors. One bioreactor was operated at 35 ± 2℃, and another was at 55 ± 2℃. The thermophilic anaerobic hydrogen fermentation (TAHF) bioreactor obtained a hydrogen yield of 8.4 mmol H_2/g COD larger than 5.6 mmol H_2/g COD of mesophilic anaerobic hydrogen fermentation (MAHF) bioreactor. The specific H_2-producing rate of 7.1 mmol H_2/g-VSS/hr of the TAHF bioreactor exceeds 5.8 mmol H_2/g-VSS/hr of MAHF. The recovery of electron flow is 88.7% in converting one gram of substrate in the TAHF bioreactor, and 73.2% in the MAHF bioreactor. Acetate and Butyrate acid predominated in the MAHF bioreactor, but ethanol and Acetate predominated in the TAHF. The thermophilic bioreactor achieves higher specific H2-producting rates and hydrogen yields.