Evaluation of the Big Muddy Field Low-Tension Flood Demonstration Project.

摘要

A commercial scale low-tension flood (micellar-polymer) demonstration project was conducted in the Second Wall Creek Reservoir in the Big Muddy Field in east central Wyoming. The cost-shared, low-tension flood used a 0.1 pore volume preflush and a 0.1 pore volume low-tension slug followed by a polymer drive bank. The sulfonate used in the low-tension slug was a blend of both low and high molecular weight synthetic sulfonates. Dow Pusher 500, a dry polyacrylamide polymer, was used in both the low-tension slug and polymer drive bank for mobility control. Although project oil recovery was or will be significantly less than originally predicted, the low-tension process successfully mobilized waterflood residual oil. The primary factor contributing to lower than anticipated recovery was lack of containment of the injected fluids in the reservoir. Behind-pipe communication in abandoned or reconditioned wellbores in the project area represented the most probable source of fluid migration from the reservoir. Fluid entry from other reservoirs occurred concurrently with migration of the fluids from the reservoir. Fluid containment deteriorated significantly when injection pressures during the polymer injection period were allowed to exceed the formation parting pressure. Injectivity in the relatively low permeability reservoir was a continuing operational problem. 6 refs., 78 figs., 19 tabs. (ERA citation 14:012567)