含硫酸根的高碳氮比废水产甲烷强化技术及酶学机制

Enhancement of methane production from high C/N ratio wastewater containing sulfate and its enzymatic mechanism

污泥蛋白质回收已成为剩余污泥资源化的有效途径之一,研究其提取残液的产甲烷强化技术不仅可助力剩余污泥蛋白质提取技术的应用进程,也可为化工、食品行业高硫酸根和高碳氮比废水的厌氧生物处理提供有益参考.结果表明,铁及其螯合物添加不仅可有效促进水解酸化与产甲烷过程关键酶的活性,还可显著抑制亚硫酸盐还原酶的活性,产气效果得到明显提高.当添加10μmol·L^(-1)氨三乙酸与40 mg·L^(-1)零价铁时,累积产气率达196.2 m L·g-1COD,与对照实验相比,提高了123.97%.多糖是含硫酸根的高碳氮比废水产甲烷的主要底物.结合关键酶活性的变化发现,与酸化过程相比,多糖与蛋白质水解是提高产甲烷效果的限速步骤.

Recovery of sludge protein has become one of the most efficient routes for utilizing waste activated sludge( WAS). It is helpful for the application of WAS protein recovery and will provide useful information for high C/N ratio wastewater containing sulfate from chemical and food industries to study the enhancement of methane production from wastewater of protein recovery. The results showed that the addition of iron and its chelate efficiently enhanced methane production via promoting the activities of key enzymes of hydrolytic acidification and inhibiting those of sulfate reductase. When 10 μmol·L-1nitrilotriacetic acid( NTA) and 40 mg·L-1Fe0 were added,the cumulative biogas production rate reached 196.2 m L·g-1 COD. It increased by 123.97%,compared with the control. The polysaccharides were the main substrate for methane production from high C/N ratio wastewater containing sulfate. The hydrolysis of polysaccharides and proteins was the limiting step to improve methane production,compared with the acidification process,by integrating the variations in the activities of key enzymes.