Dizer H, Bartocha W, Seidel K, López Pila J M, Grohmann A
Institut für Wasser-, Boden- und Lufthygiene des Bundesgesundheitsamtes, Berlin.
Zentralbl Hyg Umweltmed. 1993 Sep;194(5-6):490-507.
The water of a channel in Berlin which is highly polluted by municipal sewage effluent is treated at the phosphate elimination plant (PEP) Tegel by flocculation and filtration in order to reduce eutrophication in the following Lake Tegel. The elimination of bacteria and coliphages in the effluent of the PEP was investigated in a scale pilot UV irradiation reactor installed at the outlet of the PEP Tegel. The influence of technical parameters such as flow rate and the arrangement of 23 UV lamps in the reactor on the inactivation was tested. The UV irradiation dose was calculated 119 mJ/cm2 and 49 mJ/cm2 at a flow rate of 50 m3/h and 120 m3/h, respectively and for an irradiation zone of 97.5 cm. The colony count of bacteria and concentrations of coliform organisms, E. coli, and feacal streptococci as well as the plaque forming units of coliphages in the influent of the UV reactor were reduced 2-3 lg units by an irradiation dose of 119 mJ/cm2. These elimination was found being only one lg unit at a UV irradiation dose of 49 mJ/cm2. The concentration of E. faecalis and Coliphages f2 seeded into the influent of the UV reactor decreased after UV irradiation by 119 mJ/cm2 by 2-4 lg units and 1-2 power of magnitude, respectively. A UV dose of 49 mJ/cm2 caused only a 90% elimination of E. faecalis and a 75% inactivation of Coliphages f2. Due to heterogenous distribution and the different retention period of the inflowing water in the irradiation zone, the inactivation of E. faecalis and Coliphages f2 was unequal. Both test organisms decreased in the middle of the reactor up to 2 lg units more than at the sides of the reactor. The hygienic-microbiological quality of a secondary effluent from sewage treatment plants can be improved by a combination of flocculation-filtration and UV irradiation due to their additive elimination effect. However, this UV reactor, which was tested under field conditions can only ensure the inactivation of bacteria and coliphages in the pretreated effluent, if more homogenous distribution of the inflowing water can be achieved. Further, the water must be irradiated by a higher UV dose.
柏林一条受城市污水排放严重污染的渠道中的水，在泰格尔磷酸盐去除厂（PEP）通过絮凝和过滤进行处理，以减少下游泰格尔湖的富营养化。在安装于PEP泰格尔厂出水口的中试规模紫外线照射反应器中，研究了该厂出水中细菌和噬菌体的去除情况。测试了诸如流速以及反应器中23盏紫外线灯的布置等技术参数对灭活效果的影响。在流速分别为50立方米/小时和120立方米/小时且照射区为97.5厘米的情况下，紫外线照射剂量分别计算为119毫焦/平方厘米和49毫焦/平方厘米。紫外线反应器进水口处的细菌菌落计数、大肠菌群、大肠杆菌和粪链球菌的浓度以及噬菌体的噬菌斑形成单位，在119毫焦/平方厘米的照射剂量下减少了2 - 3个对数单位。在49毫焦/平方厘米的紫外线照射剂量下，这些去除量仅为1个对数单位。接种到紫外线反应器进水口的粪肠球菌和噬菌体f2的浓度，在119毫焦/平方厘米的紫外线照射后分别降低了2 - 4个对数单位和1 - 2个数量级。49毫焦/平方厘米的紫外线剂量仅导致粪肠球菌90%的去除和噬菌体f2 75%的灭活。由于流入水中在照射区内分布不均且停留时间不同，粪肠球菌和噬菌体f2的灭活情况不相等。两种受试生物在反应器中部的减少量比在反应器两侧多高达2个对数单位。由于絮凝 - 过滤和紫外线照射具有累加去除效果，污水处理厂二级出水的卫生微生物质量可以通过二者结合得到改善。然而，这个在现场条件下测试的紫外线反应器，只有在能够实现流入水更均匀分布的情况下，才能确保对预处理出水中的细菌和噬菌体进行灭活。此外，水必须用更高的紫外线剂量进行照射。
