Nasser A M, Paulman H, Sela O, Ktaitzer T, Cikurel H, Zuckerman I, Meir A, Aharoni A, Adin A
Water Quality Research Laboratory, Ministry of Health, Israel.
Water Sci Technol. 2006;54(3):83-8. doi: 10.2166/wst.2006.452.
Wastewater reuse in arid regions is important for the production of a water resource to be utilised for non-potable purposes and to prevent the environmental transmission of disease-causing agents. This study was conducted to evaluate the effect of water quality on the comparative disinfection efficiency of viruses, bacteria and spores by UV irradiation. Furthermore, the microbial quality of effluent produced by coagulation, high rate filtration (HRF) and either UV irradiation or chlorination was determined. Using low pressure collimated beam, a UV dose of 80 mWs/cm2 was needed to achieve a 3-log10 inactivation of either rotavirus SA-11 or coliphage MS2, whereas over 5-log10 inactivation of E. coli was reached with a dose of only 20 mWs/cm2. B. subtilis inactivation was found to be linear up to a dose of 40 mWs/cm2 and then a tailing up to a UV dose of 120 mWs/cm2 was observed. It is worth noting that effluent turbidity of < 5 NTU did not influence the inactivation efficiency of UV irradiation. Operation of a pilot plant to treat secondary effluent by coagulation, HRF and UV disinfection at a UV dose of 80 mWs/cm2 resulted in the production of high quality effluent in compliance with the Israel standards for unrestricted irrigation (< 10 CFU/100 mL faecal coliform and turbidity of < 5 NTU). Sulphite reducing clostridia (SRC) were found to be more resistant than coliphages and F coliform for UV irradiation. The results of this study indicated that UV disinfection is suitable for the production of effluents for unrestricted irrigation of food crops.
干旱地区的废水回用对于生产可用于非饮用水目的的水资源以及防止致病因子的环境传播至关重要。本研究旨在评估水质对紫外线照射下病毒、细菌和孢子相对消毒效率的影响。此外，还测定了通过混凝、高速过滤（HRF）以及紫外线照射或氯化处理产生的出水的微生物质量。使用低压平行光束时，需要80 mWs/cm2的紫外线剂量才能使轮状病毒SA-11或大肠杆菌噬菌体MS2达到3个对数10的灭活，而仅20 mWs/cm2的剂量就能使大肠杆菌达到超过5个对数10的灭活。发现枯草芽孢杆菌在40 mWs/cm2的剂量之前灭活呈线性，然后在高达120 mWs/cm2的紫外线剂量下出现拖尾现象。值得注意的是，出水浊度<5 NTU不会影响紫外线照射的灭活效率。运行中试装置，通过混凝、HRF和80 mWs/cm2的紫外线消毒处理二级出水，产生了符合以色列无限制灌溉标准（粪大肠菌群<10 CFU/100 mL且浊度<5 NTU）的高质量出水。发现亚硫酸盐还原梭菌（SRC）对紫外线照射的抗性比大肠杆菌噬菌体和F大肠杆菌更强。本研究结果表明，紫外线消毒适用于生产用于粮食作物无限制灌溉的出水。
