金鑫,符波,朱慧,刘宏波,刘和.产甲烷抑制剂氯仿对污泥厌氧消化中同型产乙酸作用的影响[J].环境科学学报,2019,39(5):1536-1543
产甲烷抑制剂氯仿对污泥厌氧消化中同型产乙酸作用的影响
- Effect of methanogenic inhibitor chloroform on homoacetogenesis during anaerobic digestion of sewage sludge
- 基金项目：江苏省自然科学基金（No.BK20181344）；国家自然科学基金（No.51678280）；江苏省厌氧生物技术重点实验室开放课题（No.JKLAB201711）
- 金鑫
- 江南大学环境与土木工程学院, 江苏省厌氧生物技术重点实验室, 无锡 214122
- 符波
- 1. 江南大学环境与土木工程学院, 江苏省厌氧生物技术重点实验室, 无锡 214122;2. 江苏省水处理技术与材料协同创新中心, 苏州 215009
- 朱慧
- 江南大学环境与土木工程学院, 江苏省厌氧生物技术重点实验室, 无锡 214122
- 刘宏波
- 江南大学环境与土木工程学院, 江苏省厌氧生物技术重点实验室, 无锡 214122
- 刘和
- 江南大学环境与土木工程学院, 江苏省厌氧生物技术重点实验室, 无锡 214122
- 摘要：厌氧消化是城市污泥常用的资源化处理方式，添加产甲烷抑制剂得到的发酵产物乙酸相比于甲烷被认为更具附加值.同型产乙酸途径是污泥厌氧发酵产乙酸途径之一，然而产甲烷抑制剂的存在对其影响尚不明确，这对污泥厌氧发酵产酸工艺的优化和应用至关重要.本文研究了不同氯仿浓度抑制产甲烷条件下挥发性脂肪酸、气体浓度及同型产乙酸菌和总细菌数量的变化，基于乙酸的稳定性碳同位素分馏效应分析了不同温度条件下氯仿对同型产乙酸作用的影响.结果显示，0.1%和0.5%（V/V）氯仿浓度条件下最高乙酸浓度分别为24.5和22.4 mmol·L-1，远低于对照组的52.6 mmol·L-1.氯仿抑制产甲烷条件下乙酸的稳定碳同位素丰度δ13C值均高于污泥有机质的δ13C值，50℃时乙酸的δ13C值最高，且同型产乙酸菌相对丰度也低于15和30℃条件下.可见，产甲烷抑制剂氯仿同时能够抑制同型产乙酸作用，0.5%浓度下的抑制效果高于0.1%浓度下，且50℃条件下其抑制作用强于15和30℃条件下.
- Abstract：Anaerobic digestion is a widely used treatment method for resource recycling from sewage sludge. Fermentation product acetate which are more value-added than methane could be obtained under methanogenic inhibition condition. Homoacetogenesis is one of the acetate-producing pathways during anaerobic digestion of sewage sludge. However, the effect of methanogenic inhibitors on homoacetogenesis has not been well understood, which is crucial for the optimization and application of sludge anaerobic digestion process for acetate production. In this study, the change of volatile fatty acids, gas concentration, homoacetogenic bacteria number and its abundance in total bacteria were investigated in the sludge anaerobic digestion under methanogenic inhibition by different concentrations of chloroform. The effect of chloroform on homoacetogenesis under different temperatures was also analyzed based on the stable carbon isotope fractionation of acetate. The maximum acetate concentration was 24.5 and 22.4 mmol·L-1 for 0.1% and 0.5% (V/V) of chloroform treatments, respectively, which were much lower than that of the control (52.6 mmol·L-1). The δ13C values of acetate of chloroform treatments were all higher than that of sludge organic matter with the highest δ13Cacetate at 50℃, and the relative abundance of homoacetogens was also lower than that of 15 and 30℃. The results indicated that the methanogenic inhibitor chloroform also inhibited homoacetogenesis in sludge anaerobic digestion with stronger inhibitory effect of 0.5% concentration than 0.1%, and the inhibition at 50℃ was stronger than 15 and 30℃.
