Study On Oil-sludge Displacement Technology Of Zi Bei Recovery Plant

There has been about 3000 m3 oily sludge produced per year during the process of the Zi Bei Oil Production Plant,and the harmful substances will cause severely impair to the surrounding environment if it can not be manage in time.The conventional processing method can not solve this problem effectually due to high cost or substandard treatment,and the heterogeneity contradiction of inter-layer and inner-layer are also becoming more and more serious after years of water injection development,which make development result unsatisfactory.In order to solve these issues,the oil sludge profile control system formulation and optimization of process parameters have been studied.The emulsion type,gel type and volume expansion type granular oil sludge profile control agent,which is suitable for the Chang 6 reservoir of Zi Bei Oil Production Plant have been made up and evaluated,and used for profile process design,meanwhile,pilot test was carried out in 8418-6 well group of the block of Jian Yu Cha.The results shows that profile control system of emulsion and gel type oily sludge has the characteristics of high plugging rate,good temperature resistance and salt resistance and good thermal stability,however,the volume expansion granular oil sludge profile control agent has the characteristics of slow expansion speed,good temperature resistance and salt resistance,good viscoelasticity and good water retention.Using the combination system,8418-6 well group average injection starting pressure increased from1.17 MPa to 4.23 MPa per day,water absorption index fell to 39.84m3/MPa from 79.37m3/MPa per day,and wells daily oil reached 1.03 t.Through the combination of emulsion type,gel type and volume expansion granular type of oily sludge profile control agent not only can achieve the effect of increasing oil precipitation effectively,but also meet the needs of the Chang 6reservoir adjustment.