木薯酒精废水高温厌氧发酵产氢研究

Studies on hydrogen production from thermophilic anaerobic fermentative of cassava ethanol wastewater

以木薯酒精废水为厌氧发酵产氢底物,以中温(37℃)厌氧颗粒污泥作为接种物,研究了高温条件(60℃)下厌氧发酵产氢的可行性;并比较了60～80℃条件下的累积产氢量、产氢速率和液相发酵产物组成,以确定温度对木薯酒精废水厌氧发酵产氢的影响以及不同温度下厌氧发酵产氢菌的代谢类型。结果表明,60℃时累积产氢量为383mL(木薯酒精废水用量140mL)、产氢率为70.0mL(以每克挥发性固体(VS)计),中温厌氧颗粒污泥适合作为高温条件下木薯酒精废水厌氧发酵产氢的接种物;从60℃升高到80℃时,累积产氢量逐渐下降,最大产氢速率逐渐降低,80℃时产氢完全受到抑制,70℃为产氢的临界点,低于70℃时厌氧发酵产氢菌的代谢类型属典型的丁酸型发酵,此过程中伴随着大量氢气产生,大于等于70℃时,正丁酸生成受到严重抑制,累积产氢量迅速降低;氢气的产生主要来自于溶解性碳水化合物的分解。

The feasibility of hydrogen production from cassava ethanol wastewater with mesophilic anaerobic granular sludge as seeding sludge was studied. The effect of temperature on cassava ethanol wastewater anaerobic fermentative and metabolic pathways of microorganisms was investigated through the comparison of the cumulative hydrogen production, hydrogen production rate and liquid fermentative products at various temperatures. The results showed that mesophilic anaerobic granular sludge presented perfect efficiency for anaerobic fermentative, 140 mL cassava ethanol wastewater could produce total of 383 mL hydrogen at 60℃, given the hydrogen production rate of 70.0 mL/g. The cumulative hydrogen production was decreased with increasing the temperature from 60℃to 80 ℃. 70℃ was a critical point for hydrogen production,when the temperature below 70℃, the fermentation belonged to bu- tyrate type with higher hydrogen production, when the temperature above the 70℃, the hydrogen produced in the anaerobic fermentative was mainly from the decompose of soluble organic carbon.