Design Of Upgrading Project For Jia-river Wastewater Treatment Plant In Qinhuangdao

Qinhuangdao City is an important coastal city in Bohai Sea area,and its environmental problems have attracted much attention.With the rapid development of economy in Qinhuangdao Changli County,the amount of industrial and domestic wastewater increases sharply,which makes the Jiahe Waste Water Treatment Plant(WWTP)unable to meet its development needs,and a large amount of pollutants was discharged into the Jia River,and causing a serious impact on the area of Qinhuangdao’s rivers and Bohai Sea.In order to keep the good water environment quality in Qinhuangdao,to promote the healthy development of urban economy and tourism,to ensure the people’s normal life and work,as well as the normal work of the Central Government Department,it is necessary to control the pollution of the Jia River,to improve the effluent quality discharged into the river,and to upgrade the WWTP.The current situation of Jiahe WWTP is located in Qinhuangdao Changli County Longan Industry Zone with a design capacity of 7×10~4m~3/d,covered an area of 11.6ha,a combined process of biological oxidation pond/UV disinfection was used,the effluent quality met the class I-A standard in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB18918-2002).According to the agreement sighed by Longan Industry Zone Management Committee and the various enterprises located in Changli Longan Industry Zone,combined with Wastewater Quality Standards for Discharge to Municipal Sewers(CJ343-2010)emission index,the influent quality of the project is determined.In combination with the local standard of Tianjin Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(DB12/599-2015),the effluent quality meets the V standard in the Environment Quality Standards for Surface Water(GB3838-2002).This project designs to a new wastewater treatment system and abolishes the original biological combination pond process.The design capacity of the project is7×10~4m~3/d,and the newly requisition land is 1.73ha on the north side of the original plant area.According to the high standard effluent quality,the A/A/O&MBR wastewater treatment process was determined to use by comparing with oxidation ditch&coagulation-flocculation sedimentation tank&deep-bed filter.Treatment of sludge produced adopts mechanical thickening dewatering.The project investment is RMB165.1365 million,the unit operating cost is RMB1.19.The project reduces pollutants discharged,improves water environmental quality,protects the safety of drinking water sources and improves the health level of residents,resulting in significant environmental and social benefits,as well as indirect economic benefits.