Polymerflooding has been considered a suitable method for reservoirs with viscosities up to 150 mPa•s. The authors of the complete paper verify that alternating injection of polymer and water in the Bohai Bay of China proved effective and economical for heavy oil fields, even offshore. This polymerflooding pilot of initially continuous, and then alternating, injection can provide a useful technical reference for similar reservoirs.
Introduction
Heavy oil reserves are abundant in the Bohai oil field of China. The development of the field has proved t hat the field with lower viscosity (less than 350 mPa•s) can be developed effectively by waterflooding, while the unconventional heavy oil reservoir with high viscosity has not formed a mature development mode.
To better use interwell reserves, a pilot polymerflooding test has been conducted in the NN field since 2008. The cumulative production of nine wells in the surrounding area reached 10.80×104 m3, which confirmed that polymer fluid injection had a good displacement effect on unconventional high-viscosity crude oil.
