Abstract：The ratio between Mixed Liquor Volatile Suspended Solid (MLVSS) and Mixed Liquor Suspended Solid (MLSS), the specific hydrogen producing rate by MLVSS and the COD removal rate are normally used to evaluate the hydrogen-production efficiency of anaerobic activated sludge in fermentation processes, but they suffer from some drawbacks. In order to evaluate the hydrogen-production efficiency of anaerobic activated sludge in fermentation processes, a detection method using iodonitrotetrazoliumchloride (INT) is proposed and optimized for detecting the specific dehydrogenase activity in the flocs. The correlation between dehydrogenase activity and the specific hydrogen production rate of the activated sludge is analyzed. The results show that the optimal conditions for detecting INT-dehydrogenase activity are as follows. A 2.8 mL reaction system, including 0.3 mL sludge sample with a mixed liquor volatile suspended solids of 3.5 ~ 12.5 g/L, 1 mL 19.8 μmol/L INT and 1.5 mL sodium acetate buffer with a pH of 5, is put in dark for 30 min under 45℃ with oscillation. Concentrated sulfuric acid of 98% is used as the reaction termination agent, while the anhydrous ethanol is used as the extraction solvent. The absorbance is measured at 438 nm. The dehydrogenase activity of the activated sludge is very highly correlated with its specific hydrogen production rate, excellently reflecting the hydrogen-producing activity.
2009, Vol. 27 
