Study On Design And Trial Operation Of A Sewage Treatment Plant In An Industrial Park

Some cities in China encourage industrial enterprises to withdraw from urban areas and merge into industrial parks,and at the same time promote the transfer of the whole industry to industrial parks.This paper takes the sewage plant to be built in changji industrial park as the research object,predicts and calculates the amount of sewage to be treated according to the population number and the drainage condition of the enterprises in the park,and determines the actual scale of the sewage plant and the site of the plant for construction.According to the characteristics of the inlet water quality,the actual scale of the water plant and the requirements of the effluent water quality,five secondary sewage treatment processes and two advanced sewage treatment processes were compared in terms of technology and economy,and the sludge treatment process and disinfection process were analyzed and determined.The structure of the treatment unit is also designed and calculated.At the same time,the whole process of the construction and commissioning of the sewage plant is tracked and analyzed.The research results are as follows:?1?The quantity of sewage to be treated is forecasted and calculated,and the short-term treatment capacity of the sewage plant is determined to be 5000m³/d.The water quality standard of the treated effluent will be implemented as level A standard in the"standards for pollutant discharge of urban sewage treatment plants of the People's Republic of China"?GB18918-2002?.?2?According to the characteristics of water quality,the secondary sewage treatment with CASS technology as the core was selected in the principle of"more efficient,more energy-saving,more economical and more applicable".Sewage treatment based on"efficient sedimentation tank+fiber tray filter";Sludge treatment will adopt the treatment and disposal method of direct concentration and dehydration followed by outward landfill;Chlorine dioxide will be used as a disinfectant for effluent.?3?Referring to relevant design specifications and parameters,the design and calculation of the pre-treatment stage,secondary treatment stage,deep treatment stage,disinfection stage,sludge treatment stage and other monomer structures and buildings needed by the sewage plant are carried out.?4?The sewage treatment plant started water trial operation on October 2,2018 and ended on March 18,2019.Among them,the average COD inlet concentration was 821.75mg/L,the average effluent concentration was 23.46mg/L,and the average treatment degree was 96.65%.The average influent concentration of NH₄⁺-N was 46.35mg/L,the average effluent concentration was 1.23mg/L,and the average treatment degree was 97.09%.The average concentration of TN inlet water was 64.85mg/L,the average concentration of outlet water was 5.56mg/L,and the average treatment degree was 90.75%,the average concentration of TP inlet water was 8.53mg/L,the average concentration of outlet water was 0.192mg/L,and the average treatment degree was 97.23%.The average pH value of inlet water was 5.85,and the average pH value of outlet water was 7.46.Among them,the amount of water inlet is lower than the design value,and the concentration of water inlet is slightly higher than the design value,but the effluent water quality can reach the expected level A standard.