Study On The Features Of Water Quality And Removal Effect Of Pollutants In A Wastewater Treatment Plant

One wasterwater plant located in Zhejiang has applied the technology including reversed A/A/O process for step feed,highly performance cascade precipitation system and fiber rotary filtration system.The effluent water quality has reached the grade A in first class standard according to GB 18918-2002 "urban sewage treatment plant pollutant discharge standard".According to the statistic results of monitoring data from January to December2016 in this plant,it is indicated that inflow amount,temperature is closely affected by seasonal change.Inflow amount is significantly affected by rainfall,residential and industrial discharge;the inflow indicators,COD,SS,NH₃-N,TP,TN,are also affected by rainfall and seasonal change.BOD₅ is not related to other indicators.After analyzing the biodegradability in inflow water,it shows that BOD₅ is very low in inflow,which may cause the ratio of biochemical indices,C/N ratio and biodegradability stay low.The study has found that through whole years running,although obvious fluctuation exists in inflow amount,quality and temperature,this wastewater plant can still compliance with 100% pass the requirement for effluent.It indicates that this plant process and monitor those running facility very well,the treatment technology has great stability and the ability to resist impact load.This wastewater treatment also adapts to water treatment for rainfall and wastewater combination in urban area.The chemical indicators in effluent,like BOD₅,COD,TP and SS are correspondingly related to the indicators in inflow,except TN.After all,it is proved that this wastewater plant has high and stable removal performance for BOD₅,COD and SS.This study results show that according to the change of chemical indicators in inflow,the stability and sustainability of this wastewater plant treatment can be improved from adjustment of inflow load,the ratio of nutrient elements and control of online monitoring system.