Research Of Oily Wastewater Treatment Technology In Xing Bei Oilfield

In mid-to late phase of oil drilling,water cut will be higher than 70%.It will cause great environmental hazard if the wastewater from water-oil separation is not properly treated.Wastewater in most oilfields will be reinjected after treatment,which makes the treating process more crucial.Based on the main problems of 27 sewage stations in Xingbei oilfield in 2016,two heavy sewage plants—Xing 25 and Xing 19—are focused in this dissertation.Factors influencing the quality of sewage in filtration system,dosing system and aeration system are analyzed.Methods to improve the quality of wastewater are proposed based on the operation parameters of indoor optimizing library.A method that is validated by opening the filter tank and inspecting in the field is demonstrated for directly determining the internal situation of a filter tank based on its backwash curve.It is expected that with this method,problems of filter tanks will be found promptly and the labor intensity will be reduced greatly.Backwash parameters of the filter tank are optimized.A process to clean contaminated filter tank is proposed involving soaking and washing with hot water.Comparing with using demulsifier,washing with 70 °C water was found more effective.Heavy sewage containing polymer in Xing Bei oil field was studied.Microbicide GNSJ-01 was chosen,improved dry powder flocculation device was planted and was optimized.