泥膜共生/臭氧催化氧化工艺在污水处理厂提标改造中的应用OACSTPCD

Dongying S wastewater treatment plant(WWTP)underwent an upgrade to comply with more stringent sewage discharge standards.With a capacity of 20000 m3/d,the WWTP is retrofitted with an integrated fixed film activated sludge/ozone catalytic oxidation process.The process operation results indicate that the implementation of this novel process has significantly improved the removal efficiency of organic matter and nitrogen.Simultaneously,C/N in the biochemical tank decreased from 5.74 to 4.53 with a 58.9%reduction in sodium acetate carbon source dosage under virtually similar influent water quality and temperature conditions.The biochemical effluent had reductions in CODCr,ammonia nitrogen and total nitrogen from 52.2,2.2,14.0 mg/L before the upgrade to 42.8,1.2,8.7 mg/L respectively.The average CODCr of the ozone catalytic oxidation effluent is measured at 20.4 mg/L.The integrated fixed film activated sludge system forms a dense and continuous biofilm,which includes dominant bacterial groups such as Candidatus_competibacte and Nitrospira,ensures stable nitrogen conversion and effective organic matter removal.The dissolved organic matter(DOM)removal efficiency in the biochemical stage increases from 32.4%to 44.7%,and the ozone catalytic oxidation process essentially eliminated difficult-to-degrade organic compounds such as cresol and toluene in the biochemical effluent.Moreover,the cost of water treatment chemicals remains essentially unchanged before and after upgrading,meeting the increased emission requirements.