An Inactive Water-Wet Film for Paraffin Inhibition in Qinghai Oilfield

Paraffin precipitation is seriously affecting crude oil production in Qinghai Oilfield.In order to solve the increasingly worsening problem of paraffin precipitation and achieve the goal of high and stable yields at low cost,this paper comprehensively analyzed the application status of paraffin inhibition technologies in Qinghai Oilfield on the basis of investigation,and proposed a new paraffin inhibition method,namely water-wet inactive film technology.A new chemical is added into tubing to form a water-wet inactive film on tubing surface to inhibit paraffin,corrosion and scale precipitation.Through theoretical analysis and laboratory infrared spectroscopy experiment,the paraffin inhibition mechanism of the new technique was shown in detail from the microscopic view,that is the hydrophilic groups of the inactive film strongly interact with water through hydrogen bonds to form a stable chelate,preventing paraffin deposition.Laboratory experiment and field application show that the new technology works better than traditional chemical paraffin inhibition methods, especially for oil wells with 30%-50% water cut,it can effectively control paraffin,slow corrosion,prevent scale formation,extend purge period and pump inspection interval,raise production,which shows good economic benefits and promising prospects of application.