有机酸胁迫下厌氧污泥产氢效果

乙酸、丙酸、乳酸及丁酸是厌氧发酵产氢过程中4种主要的液相末端发酵产物,其积累对产氢过程有一定的抑制作用。实验利用多种有机酸胁迫提高污泥的酸耐受能力,并以污泥中脱氢酶活性为生化指标,对不同浓度酸胁迫下厌氧污泥活性变化进行了研究。通过对胁迫后污泥产氢量及末端产物进行对比。结果表明,酸胁迫后污泥产氢量有一定增加,其中乙酸和丁酸胁迫效果最好,较对照组提高了近一倍;末端产物分析研究表明,不同的有机酸胁迫后,其产量在发酵过程中都有一定的增加,而乙酸含量在酸胁迫后都有不同程度的提高。

Effect of Organic Acids Stress on Biohydrogen Production by Anaerobic Granular Sludge

The major organic acids produced in the fermentative hydrogen production by mixed cultures were acetic acid, propionic acid, lactate acid and butyric acid, etc. which had negative effect on hydrogen production. The acid tolerance of mixed cultures was improved by the metabolites stress and the sludge activities under different stresses were investigated through the dehydrogenase activity (DHA) determination in the work. The results showed that certain metabolite stress could increase the hydrogen production and the metabolite yield, especially when acetic acid and butyric acid were used for stress. Importantly, the cumulative hydrogen quantity nearly doubled compared with the control. Interestingly, the acetic acid production enhanced extensively regardless of the stress method of all groups.