Study On The Process Design For The Second Phase Construction Of Wastewater Treatment Plant In Wudalianchi

With the rapid development of industrial, the increasing number of populationand the improvement of people’ living standards, the production of WudalianchiCity’s wastewater is increasing rapidly. Particularly large amounts of untreatedwastewater directly discharged into rivers, which brought great population into thecity and the surrounding environment and made some influences into the general’health and the living environment seriously. Therefore, in order to the sustainableeconomic development of Wudalianchi City and the goal of building it into the centralcity in the Northeast,speeding up the consuction of municipal wastewater treatmentplant is now quite urgent.With the analysis of the existing water quality, considering the design and actualinflow quality of phase1,inlow quality of phase2is determined as: BOD5=180mg/L,COD=300mg/L,SS=300mg/L,TN=40mg/L,NH3-N=25mg/L,TP=4mg/L.Effluent quality was determined as BOD5≤10mg/L,COD≤50mg/L,SS≤10mg/L,TN≤15mg/L, NH4+-N≤5（8）mg/L, TP≤0.5mg/L.The capacity of phase2was10,000m3/d.Treatment process applied was asCWSBR process with return sludge demitrification section after economic andtechrical comparison studg. Sludge will be thichened, ewatered and made intofertilizer.After phase2putting into operation, the pollutants discharge will be reduced,forexample91,213.5t/year for CODcr,62,020.8t/a for BOD5,10,5886.5t/a for SS，7.3t/afor NH4+-N，9.125t/a for TN，1.277.5t/a for TP. That means environment funition ofNe-mo Seoul river wil be improved and environment quality will be much more better,which is conducive to the development of Wudalianchi City.