Survey on injection–production status and optimized surface process of ASP flooding in industrial pilot area

• Injection–production status and contribution of ASP flooding are surveyed.
• ASP flooding adapts heterogeneous reservoir but benefited status is different.
• Plugging relief, fracturing and water plugging can improve benefited status.
• Existed problems of gathering and transportation and disposal system are demonstrated.
• Solutions and application effects of optimized surface process are evaluated.

Alkali/surfactant/polymer (ASP) flooding technology has been successfully used in Daqing Oilfield (China). Dynamic injection–production statuses of the first strong base (NaOH) ASP flooding in east region of Xing 1–2 area in the oilfield are surveyed, and several effective adjustments operated in production are demonstrated. The related problems in surface part encountered in the ASP flooding pilot area broadly include deposition behavior in oil gathering pipelines, scaling in gathering and transportation process and disposal facilities, emulsification of produced liquid (mixture of oil, water and chemicals of wells), and difficult disposal of produced water. Solutions taken to overcome the problems in the pilot area are presented and evaluated. The idea of subsurface and surface parts integration is also discussed in terms of oil recovery and operation cost. The summary of the production practices contributes to design another pattern-flood pilot and accelerate further application of ASP flooding.