Research On Commissioning Of Coal Chemical Wastewater By Biological Synchronous And Improved A/O Process And Foam Pollution

Coal chemical watewater is a typical high concentration of biodrgaableindustrial wastewater,which is constituted mainly by high concentration gas washingwastewater. The water quality of the coal chenical wastewater is much complex,containing a large number of phenols, long-chain alkanes, heterocyclic, ammonia,cyanide and other toxic substances, with serious foam pollution. So if the treatmenteffluent of the coal chemical wastewater reach the standard, it will provide valuablepractucal experience in the sector of sewage treatment, which has a realisticsignnificance..At the beginning, the article briefs the overview of the coal chemicalwastewater, summarizes the current status of domestic treatment of the coalchemical wastewater, describes the design data and process engineering of the entiresystem.Then the paper describes the coal chemical wastewater foam factors andcontrol measures, and make recommendations to eliminate the foam. Finally thebiological treatment unit focused on the activated sludge pond cultivation anddomestication in the Biological Synchronous Nitrogen Enriched Pool and ImprovedA/O is described.And the pollutant processing performance at the stage of start-upand stable operation and the operational phase the factors affecting of pollutants areanalysis.Through the study of factors affecting pollutants, the optimal operationcontrol parameters of the biological treatment section is proposed.The main factors of the foam in the coal chemical wastewater treatment projecthas influent COD, the concentration of toxic substances (such as total phenols), pH,the sludge concentration and so on. The experiment results showes: the control ofMLSS in greater than4000mg/L, activated carbon dosage about1500mg/L, pH5to6, influent COD was below1000mg/L, total phenol concentration in below250mg/L, could effectively reduce the volume of foam in system.After the actual operation of treatment, biological synchronous nitrogenenriched process-improved A/O process shows a very good treatment capacity tocoal chemical wastewater.The effluent COD concentration stabilizes at100mg/L,COD removal rate above90%, the effluent concentration of total phenols about20mg/L, total phenol removal rate about90%, the effluent ammonia concentrationabout5~10mg/L, ammonia nitrogen removal rate of90%. The optimum operatingparameters of the biological treatment section: about biological synchronousnitrogen enriched process pool, when the dissolved oxygen control under hypoxicconditions, the sludge concentration in3000~4000mg/L, influent ammoniaconcentration at100mg/L, it could obtain better treatment results;about improved A/O poll, the pH is adjusted by adding sodium hydrogen carbonate and methanol asthe value added carbon source, such that the pH value is maintained between6and7,C/N between3and5, improved A/O poll can be a good treatment effect.