常见污水消毒工艺设计探讨

Discussion on the Design of Common Sewage Disinfection Processes

常见的污水消毒工艺包括紫外线消毒和接触消毒两类,一般根据用地多少和是否再生利用进行选择。污水性质、排放标准和再生利用的要求决定消毒处理的程度,进而决定紫外线消毒的有效剂量和消毒剂残留浓度、接触时间。紫外线消毒灯管老化系数默认为0.5,套管结垢系数默认为0.6;采用固定堰控制渠道水位时,应防止最大时流量对应的堰上水头超出最上层灯管的有效杀菌范围。出水SS低可适当降低消毒药剂量;对于采用稳定性较差的次氯酸钠,北方或进水偏碱性的污水厂应严格执行30 min有效接触时间,消毒设施设计水量对应最大时流量。

Common sewage disinfection processes include ultraviolet disinfection and contact disinfection,which are generally selected based on the amount of land used and whether the effluent is recycled.The nature of sewage,discharge standards and recycling requirements determine the degree of disinfection treatment,and then determine the effective dose(mJ/cm~2)of ultraviolet disinfection,the residual concentration of disinfectant C(mg/L),and the contact time T(min).The default aging coefficient of the UV disinfection lamp tube is 0.5,and the default scaling coefficient of the sleeve is 0.6;When using a fixed weir to control the water level of the channel,it is necessary to prevent the water head on the weir corresponding to the maximum flow rate from exceeding the effective sterilization range of the upper layer of the lamp tube.Low effluent SS can appropriately reduce the amount of disinfectant;For sewage plants that use sodium hypochlorite with poor stability,northern or alkaline influent,a 30 minute effective contact time should be strictly enforced,the designed water volume of disinfection facilities corresponds to the maximum hourly flow rate.