城北污水处理厂紫外线消毒等效生物验证剂量测定

Determination of Reduced Equivalent Dose of UV Disinfection in Chongqing Chengbei Wastewater Treatment Plant

使用准平行紫外光束仪测定了重庆城北污水处理厂终沉池出水中粪大肠菌群的紫外线响应曲线,验证了常用剂量下紫外线辐照强度与时间的互为倒数关系,并对验证微生物和商业UV消毒反应器紫外线剂量分布模式的选择进行了讨论。结果显示,当进水粪大肠菌群的浓度取3.0×106MPN/L时,与104MPN/L和103MPN/L两个排放标准对应的目标紫外线剂量分别为11.3mJ/cm2和15.8 mJ/cm2,对应的REDMS2分别为28.2 mJ/cm2和40 mJ/cm2。分析发现,当使用等效生物验证剂量(RED)方法确定紫外线消毒系统的处理能力时,进水粪大肠菌群浓度为107MPN/L的取值过于保守,会造成设备处理能力过度富余。

UV collimated beam device was used to determine UV response curve of fecal coliform in the effluent from the final sedimentation tank of Chongqing Chengbei Wastewater Treatment Plant.The reciprocal relationship between irradiation intensity and time at conventional UV dose was verified.The selection of challenge microorganisms and the UV dose distribution of commercial UV reactor was discussed.The results show that when the influent concentration of fecal coliform is 3.0×10^6 MPN/L,the target UV doses corresponding to the limitation of 10^4 MPN/L and 10^3 MPN/L are 11.3 mJ/cm^2 and 15.8 mJ/cm^2,and REDMS2 are 28.2 mJ/cm^2 and 40 mJ/cm^2 respectively.Analysis also shows that the influent design concentration of 10^7 MPN/L is too conservative and can result in excessive redundant capacity of UV reactor.