Research and Application of Cold Production Sand Control Technology in Heavy Oil Sand Production Well of D Oilfield in Bohai Bay

Abstract

AbstractIn order to solve the problems such as easy sand production, high viscosity of crude oil and poor recovery effect of conventional cold production sand control technology in the development process of loose sandstone heavy oil reservoir in Bohai Bay D oilfield, the research on sand control technology of heavy oil cold production well was carried out. In the research, the researchers optimized the cleaning agent and clay stabilizer components and dosage, and formed the pre-treatment working fluid of heavy oil cold recovery sand control well; The researchers optimized the composition and dosage of thickener, heavy oil dispersant and drainage aid, so as to realize the direct distribution of produced water with sand carrier fluid in heavy oil reservoir. The researchers optimized the supporting sand control construction parameters to form the cold production sand control technology of heavy oil sanding well, and tested various performance indexes of the sand carrier fluid. The research results show that the pre-treatment sand control working fluid developed for heavy oil cold production Wells has a cleaning rate of 92% of heavy oil scale and an anti-swelling rate of 85%, which can effectively reduce the risk of sand control string operation. The developed produced water direct carrying fluid for heavy oil reservoirs above 50 ℃ has the performance indexes of low residue (45.6 mg/L) and high visbreaking rate (92.8%). This kind of sand-carrying liquid not only meets the sand-carrying performance index, but also effectively improves the fluidity of heavy oil near the well, and avoids the “cooling effect” caused by conventional sand-carrying liquids. As of December 2020, the technology has been applied to 9 oil wells on site, with a 100% sand control success rate, an average single well daily oil increase of 3.5 t, and a cumulative oil increase of 5,074 t. The application effect is good and it is expected to greatly improve the recovery of heavy oil reservoirs. KeywordsHeavy oil reservoirSand control in cold miningFlushing agentHeavy oil dispersing agentVisbreaking rate