排水の飲用再利用プロセスにおけるエンドトキシンの制御

LPS内毒素是细菌的副产物，如果摄入，可能对人体构成威胁。研究了不同的去除方法对再生水中LPS内毒素的去除效果：1）长期土壤含水层处理法; 2）混凝絮凝法; 3）带正电微结构膜过滤法。运行一年后，土壤中细菌的生长导致土壤中LPS内毒素的产生，降低了其去除效率。此外，较长的操作时间会导致土壤吸附能力的下降。2）混凝和絮凝过程提供了令人满意的结果，在减少水中的LPS内毒素作为第一屏障。在pH为4.69时，硫酸铝剂量为80 mg/L时达到最高的内毒素去除率。但去除DOC和浊度的最佳pH值为6.35。自来水和地下水中残留的LPS内毒素浓度显著高于文献报道值。这表明需要进一步处理以实现安全的饮用水再利用。3）关于带正电荷的微结构膜，该研究证实了带正电荷的膜是从再生废水中去除LPS内毒素的有效替代方案的假设。事实上，观察到使用带正电荷的膜的LPS内毒素去除与微滤相比相当或甚至更好的去除效率，即使其具有更大的孔径。

LPS endotoxins are bacterial by-products that present a possible threat to humans if ingested. Investigation explored different removal methods to remove the LPS endotoxin from the reclaimed wastewater:1)Long term Soil aquifer treatment; 2)Coagulation and flocculation; 3)filtration through positively charged micro structure membranes.1)Long term operation of soil aquifer treatment of endotoxin proved that the efficiency decreases over time. After one year of operation, bacterial growth in the soilleads to LPS endotoxin production in the soil lowering its removal efficiency. In addition, longer operation leads to a degradation of the soil adsorption capacity.2)Coagulation and flocculation process provided satisfactory results in reducing LPS endotoxins in water as a first barrier. The highest endotoxin removal was achieved at an aluminum sulfate dose of 80 mg/L at a pH of 4.69. However the optimum pH for DOC and turbidity removal is 6.35.The residual LPS endotoxin concentration was significantly higher than the reported value in tap and groundwater. This suggests a need for further treatments for safe potable reuse.3)With respect to positively charged micro structure membranes, the study confirmed the assumption that positively charged membranes are an effective alternative for LPS endotoxin removal from reclaimed wastewater. Indeed, comparable or even better removal efficiency of LPS endotoxin Removal using positively charged membranes than the microfiltration was observed, even though it has a larger pore size.