两相厌氧系统中产甲烷相有机酸转化规律

研究了两相厌氧系统产甲烷相中有机酸转化规律.以产酸相、产甲烷相COD负荷分别为41.5 kg/(m³·d)、6.05kg/(m³·d)的连续流试验装置培养种泥,运行稳定后,进行静态试验采用气相色谱仪(GC-122型)分析有机酸组成及含量结果表明,反应器相同位置的微生物降解转化有机酸速率快慢依次为:乙酸＞乙醇＞丁酸＞丙酸;利用乙醇产乙酸的微生物与产甲烷菌所需最佳pH值范围相近;乙醇型发酵是充分发挥两相厌氧系统功能的最佳发酵类型;在产甲烷反应器中,大部分挥发酸的最终降解都要经历乙酸降解途径才能完成,造成乙酸的降解转化相对缓慢,成为厌氧工艺中的限速步骤.

Organic Acids Conversion in Methanogenic-phase Reactor of the Two-phase Anaerobic Process

Experiments on organic acids conversion in methanogenic phase of the two phase anaerobic process were conducted. The results showed that when the acidogenic phase was in mixed acids fermentation and its load was 41.5 kg/(m³·d), the load of methanogenic phase was 6.05 kg/(m³·d), the substrate conversion velocity of bacteria inhabited at the same height of UASB reactor as follows: acetic acid>ethanol>butyric acid>propionic acid; ethanol utilized microbial had the same pH range as methanogenic bacteria; ethanol type fermentation was the optimal acidogenci type fermentation for the two phase anaerobic process; the conversion of acetic acid was rather high, but the others organic acids will be convert to acetic acid make it the rate limiting step for anaerobic degradation.