Integrated Global Optimization of Displacement Efficiency in Hydrocarbon Reservoirs

摘要

In this paper, an integrated numerical technique is presented tornimplement global optimization of displacement efficiency inrnhydrocarbon reservoirs. This technique chooses the net presentrnvalue (NPV) as an objective function, which accounts forrnproduction- and injection- performance as well as reservoirrnperformance. The flowing and various artificial liftingrnmethods are incorporated into the production performancernmodels, which have been successfully applied in more thanrnforty oil fields. Meanwhile, the reservoir geological model isrnimproved by continuous monitoring and surveillance. Thenrnthe objective function is maximized to generate the optimumrnfield production-injection strategies at different developmentrnstages using a hybrid genetic algorithm (GA). Such anrnintegrated technique can maximize the displacementrnefficiency in a fixed well pattern and/or an oil field underrndifferent practical constraints. This technique is applied in arnwater-alternating-gas (WAG) miscible flooding reservoir, andrnthe field performance has shown that the displacementrnefficiency is significantly improved and the productioninjectionrnrates are well controlled. The field water-cut remainsrnlow and stable, though the gas-oil ratio is slightly higher thanrnthe original ratio. This method can be applied to develop thernoptimum production- and injection- strategies in arnhydrocarbon reservoir so that the displacement efficiency isrnmaximized and the reservoir life is extended.