Orbal Oxidation Ditch Process Commissioning In Wasterwater Treatment Plant At Low Temperature

Along with the national twelfth five-year plan, the sewage treatment plant for nitrogen and phosphorus removal requirements more stringent, Orbal oxidation ditch sewage treatment plant of Shanxi as a mainstream technology, low temperature in winter conditions, ensure the better play its contaminant degrading ability, commissioning work be imperative. In this form, in order to solve the Jiaocheng County sewage treatment temporary winter appeared some questions, ultimately determine my graduation research topic for the northern sewage treatment plant commissioning, the focus is on the N and P eutrophic element removal.In the sewage treatment plant commissioning in4months, according to the existing activated sludge sewage serious aging, mud loose, aeration control is poor, two sedimentation pond floating sludge, removal effect of nitrogen and phosphorus and other problems, was tested and analyzed the adoption of pipe insulation, calibration instrument, increasing internal reflux, determine the reasonable mud weight to ensure that the sludge update. After the commissioning of sewage denitrification and phosphorus removal function has been strengthened, two sedimentation tank mud phenomenon disappears. Shale stability, identified that sludge activity and contaminant removal effect best dissolved oxygen, MLSS, through the actual reflux ratio adjustment of parameters, determined the guarantee the removal effect of nitrogen and phosphorus of optimum reflux ratio, combined with the actual situation determines the average sludge discharge quantity. In December SV30and SVI value of sewage sludge increased greatly, the biological microscopy confirmed there was a slight filamentous bacterium sludge expansion, depending on the quality and running status determine the reason of sludge bulking matrix deficiency, BOD-sludge load is low, so the use of adding manure increased BOD method, after a month adjustment of sludge bulking are addressed, but in winter, by affecting the activity of nitrifying bacteria, nitrogen removal effect is very poor NH3-N removal rate of59%.Debugging results show that, under winter conditions, Orbal oxidation ditch process in the removal of COD, BOD5, SS removal effect is obvious, the normal operation can achieve a level of A effluent standard, and the water temperature, water volume change, still can ensure a higher removal rate. TP sludge age longer effects, processing efficiency is not high, but in the influent TP content does not exceed the design requirements of the circumstances, can reach the level of A treatment effect. Appropriate temperature conditions, normal operation, oxidation ditch denitriding effect is good, but the nitrogen removal efficiency is influenced by temperature, cold winter conditions, basic stop, this is also the northern sewage treatment plant the exists generally problem.Sludge aging problem solving, identified both can guarantee the reactor in a certain amount of activated sludge, sludge activity and high processing effect of the operating parameters:dissolved oxygen control, the outer ditch was0mg/L～0.5mg/L, mg/L channel in0.5～1.5mg/L,1.5mg/inner ditch L～2.5mg/L; MLSS concentration control in3600～4000mg/L, and SV30in43%～50%, SVI value in126～139, the sludge reflux ratio in100%, sludge age control in about20d, long effect of phosphorus removal, the time is too short, effect of nitrification.Aiming at the low temperature, BOD-sludge load caused by low activated sludge bulking, puts forward effective outrightly programs after the debugging of sludge bulking problem solved. Winter conditions to ensure the treatment effect, can adopt larger reflux ratio and increase the mud way ensuring the oxidation ditch activated sludge. Water running in winter, should pay attention to insulation, cold-proof measures, conditional waterworks construction can be laid at the bottom of the pool of thermal insulation pipeline, so as to ensure the normal functions of nitrogen in water, water shortage of water should pay attention to structure of the operating parameters are adjusted, design should pay attention to long term planning and the recent construction of the combination, avoid a shortage of funds at the same time, but also can avoid the water plant construction, operation unnecessary waste.