In the Lick Creek Field of Bradley County, Arkansas, Phillips Petroleum Company has used a single stage, nonionic polymer treatment to combat severe channeling problems in a CO2 water-alternating-gas (WAG) operation. After treating two of the 23 injection wells in the field, production has increased by 65 bbl/day. The field, consisting of 23 injection wells and 38 producers, was unitized in 1976 to initiate CO2 injection into the reservoir. Alternating CO2 and water (WAG) flooding techniques have been used. Channels had developed throughout the field and flooding was becoming uneconomical. Previous E0R treatments using an anionic polyacrylamide were successful for only a few cycles of CO2-water injection. Failure was attributed to the inability of anionic crosslinked polymer to withstand the acidic environment created by CO2. The successful treatments were composed of single stages of injection of a low viscosity monomer solution containing an organic crosslinker. The rigid polymer gel which is formed in-situ to block high permeability channels has remained stable in the CO2 environment. Laboratory studies dealing with the CO2 resistance of the polymer, tracer surveys, job design considerations, and field results are presented.

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