Research On The Start-up And Initial Operation Adjustment Of Tangjiatuo WWTP

Start-up and initial operation adjustment of Tangjiatuo wastewater treatment plant were studied.The different conditions for the WWTP operation were simulated by GPS-X in order to supervise the initial operation management.â‘ During the start-up of primary settler,the minimal and maximal concentration of SS in the influent was 77mg/l and 440mg/l,respectively.The concentration of SS in the effluent was36-382 mg/l.The removal efficiency of SS was inceased with the start-up time.After about 20 days,it was stably at 10～20%,indicating that the primary settle was steadily running.â‘¡The acitved sludge from the primary settler was inoculated the biological reactors and was cultured.However,As the organics components concentration of the wastewater were very low,the sluge increased very slowly,and after 20 days,MLSS was less than 1000mg/l.According to investigation and practise,it was decided to use landfill leachates as organic carbon sourcea addition.The acitved sludge concentration increased slowly in the initial addition,and because of the sludge adoption to the leachates.After l0 days,the sludge increased rapidly,and MLSS was more than 1000mg/l.It showed that the biological reactor was successfully started.â‘¢At the late stage of the sludge continuous cultivation,the second settler was began to start.Althrough the concentration of MLSS in biological reactor and second settler were continuous by increased,the SS in the effluent was downtrended.During the early stage of start-up,SS varied in large-scale,and tended to stabilization at about 100mg/l in the 35^th day.It indicated that the second settler was steadily running.â‘£Using the GPS-X software to simulate the influence of severl important operation parameters on the system based on the actived sludge models NO.2,the operation parameters for initial operation were confirmed.The anaerobic,anoxic and aerobic HRT were 2.5h,2.5h and 3.69h,respectively.SRT of the system was 15 d,the internal cycle ratio and the external cycle ratio were 300%and 100%,respectively.Using the GPS-X to simulate the WWTP based on the designed HRTs and the simulated HRTs,respectively,the results showed that on the designed HRTs,the phosphate in the effluent was above the standard,so that the chemicas could be added to improve the removal efficiency of phosphate.⑤Using the operation parameters based on the simulation,the system was runned. Althrough COD,BOD₅ and SS in the influent varied largely,the concentration in the effluent was averagely 18mg/l,5mg/l and 10mg/l,respectively.And the efficiency was 89%,95%and 92%,respectively.It indicated the system had the ability to remove organic and SS.The maximal TP in the effluent was 1.34mg/l,and average was 0.6mg/l.The removal efficiency was 75%.The average NH₄-N and TN in the effluent were 18.7and 28mg/l,the average NH₄-N was 0.4mgl.The removal efficiency was 98% which showed the nitrficaiton was complete.However,the TN in the effluent was 17mg/l,and the removal efficiency was only about 39%,it could not meet the standard.This indcated that the dentitrification was insufficient because of the carbon source shortage in the influent wastewater...