Study On Technology Of Treatment And Reuse Of Sewage From PetroChina JinXi Petrochemical Company

PetroChina JinXi petrochemical company lies in west of liaoning province, tobohai bay. It is a very unwatered region,and a water pollution region. Late years,state local environmental protection administrations have been stricter and stricter todisposal of sewerage from industries. The original sewage treatment plant inPetroChina JinXi petrochemical company can not sufficed environmental protectionrequirement. Water and wastewater have worse index than advanced industries. Topick water from headwaters is more and more difficult. The shortage of waterresoure has become bottleneck of continuable developing of the company.In this study, the sewage of PetroChina JinXi petrochemical company is treatedand recovered in following process based on analysing the waste water qualitysystematically. Sewage is treated using grit, oil interceptor, uniformity pool, regulatepool in the first stage, which also give the next step a good input. In the second stageof the treatment process, A/O active mud way has been studied to separate organism,ammonia and nitrogen from waste water. Finally, the output of the second stage wasadvanced treated using recovery technology from Sta Maria AB company of Sweden,which consists of sedimentation, sand filter, UV sterilization, ultrafiltration, reverseosmosis and advanced oxygenation system. The content of oil,phenol,sulfide,cyanide and ammonia nitrogen in the sewageof PetroChina JinXi petrochemical company exceed the standard greatly. Forenamedprimary treatment can eliminate oil partially with 80.7% removal ratio, catch thegreat mass of sediment and rubbish, decrease the content of seston in the sewageeffectively. The content of ammonia nitrogen, COD, phenol in the sewage were veryhigh still after primary treatment. After the secondary treatment, the sewage qualitywas improved obviously, the oil content decreased further, the ammonia nitrogencontent decreased obviously,the COD value decreased 90%,the content of phenoland sulfide is little, and the water quality reached the national primary standard ofwastewater emission control regulations. The water quality of the sewage aftertreatment by membrane technology was improved greatly. Ultrafiltration systemeliminates oil,microbes and seston further, and thus reduce the fouling of reverseosmosis membrane. The COD value in the water after reverse osmosis system is lessthan 0.5mg/L,conductivity approximate 3 μS/cm. The quality of the water afteradvanced treatment can reach the standard of boiler makeup water.