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

脂多糖内毒素是细菌的副产物，如果摄入可能对人体造成威胁。探讨了再生废水中LPS内毒素的不同去除方法：1)长期处理土壤含水层；2)混凝絮凝；3)通过带正电的微结构膜过滤。1)长期运行的土壤含水层内毒素处理效果随着时间的推移而降低。经过一年的运行，土壤中的细菌生长导致土壤中产生LPS内毒素，降低了其去除效率。此外，长时间运行会导致土壤吸附能力下降。2)混凝和絮凝工艺对降低水中作为第一屏障的内毒素效果满意。当硫酸铝用量为80 mg/L， pH为4.69时，内毒素去除率最高。而去除DOC和浊度的最佳pH值为6.35。自来水和地下水中残余LPS内毒素浓度显著高于报道值。这表明需要进一步处理安全的饮用水再利用。3)对于带正电的微结构膜，本研究证实了带正电的膜是去除再生废水中LPS内毒素的有效选择。事实上，与微滤相比，使用带正电的膜去除LPS内毒素的效率相当甚至更好，尽管微滤具有更大的孔径。

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.