Study On The Removing Efficiencies And Features Of The Ecological Biological Wastewater Treatment Process

China is currently facing serious water pollution situation.As a result,the control of point-source pollution such as wastewater treatment plants becomes very important.The designed effluent COD,BOD₅,NH₃-N and TP of an ecological wastewater treatment plant in Guangdong province meets the Class ? water standards of Surface Water Environmental Quality Standard?GB3838-2002?.The wastewater treatment plant is equipped with ecological bioreactor.The constructed wetland and"rotary filter and UV disinfection"are also used as two parallel advanced treatment processes.The ecological biological wastewater treatment process includes ecological bioreactor and constructed wetland.The study was done in an ecological wastewater treatment plant in Guangdong province,focusing on the removal efficiencies of normal pollutants,the concentration and removal efficiencies of pesticides in the wastewater treatment plant,the comparison of two advanced treatment processes on pollutants removal efficiencies,the mass balance of the ecological bioreactor,the mathematical model and optimal control of the ecological bioreactor.The study showed that the ecological wastewater treatment plant in Guangdong province could stably meet the designed effluent water quality.Five pesticides including atrazine,ethoxyquin,metolachlor,pirimicarb and tebuconazole were detected in wastewater treatment plants,and these pesticides could be removed to some extent.The removal efficiencies of COD,total nitrogen and ammonia were higher through the treatment of constructed wetland compared with"rotary filter and UV disinfection",while the latter had higher total phosphorus and suspended solids removal efficiencies.The mass balance analysis showed that carbon,nitrogen and phosphorus in the secondary treatment process were mainly removed through oxidation,denitrification and chemical phosphorus removal seperately.The mathematic model of the ecological bioreactor was built through BioWin simulation software.After the calibration of parameters through sensitivity analysis,the model was used to optimize the internal recycle ratio,and internal recycle ratio was recommended to be set at 100%instead of 150%.