Analysis And Countermeasure Of The Westward Relocation Of Sewage Outlet Of LPC To The Lanzhou Section Of The Yellow River

The industrial sewage discharged from petrochemical enterprises is characterized by large amount of discharged water,complex composition and high concentration of pollutants.Most of them contain toxic and harmful substances such as petroleum,sulfur,phenol,cyanide,nitro-compounds,aromatic hydrocarbons,arsenic and mercury.The setting or relocation of their discharging positions into rivers may affect the environmental quality of downstream surface water bodies and the utilization of water resources,aquatic ecosystems such as aquatic organisms and fish,and people’s production and living water security in downstream areas seriously.Lanzhou Petrochemical Company(LPC,for short),as an important petrochemical base in Western China,adjacent to the Yellow River and located in the upstream of the city of Lanzhou section of the Yellow River,has a sensitive geographical location.Ever since the plant was established,its industrial sewage has been discharged into downstream of Lanzhou City through a 27-km long municipal oil pollution main pipe.Due to the construction of urban rail transit in Lanzhou City,the industrial sewage outlet of LPC was relocated to the west-Xiaojingou in the upstream of Lanzhou City in 2014.Upstream discharge of industrial sewage puts forward higher requirements for enterprise water pollution control and water environmental risk control.At the same time,it is critical to conduct analysis of environmental impact and risk assessment promptly of the downstream Yellow River in Lanzhou after the industrial sewage outlet was relocated.Based on the demonstration project of Xiaojinggou sewage outlet in LPC,the research focuses on the Yellow River section of Lanzhou before and after the construction of sewage outlet,and establishes the water quality impact model accordingly to conduct the following,which provides prevalent meaning of guidance in terms of enterprise environmental protection and environmental risk prevention and control management.1)Thoroughly analyzing the discharge of industrial sewage from LPC in recent years,through data collection and on-site monitoring and investigation,and consequently obtaining the river hydrology data,water environment status,pollution receiving capacity,key targets for water resources protection,and environmental sensitive areas of the polluted water area in Lanzhou section of the Yellow River.2)Using MIKE one-dimensional and two-dimensional water quality model to analyze and predict the extent and scope of industrial sewage’s influence on Lanzhou Yellow River section under different working conditions.3)Studying and analyzing the influence caused by the relocation of sewage outlet on the important third parties,environmental sensitive targets and aquatic ecosystems in the drainage section.4)Based on the existing environmental management system and water environmental risk prevention and control measures,providing measures and suggestions for post-relocation improvement.