Optimizing Oil Recovery and CO2 Sequestration in Carbonate Reservoirs using Voidage Replacement and Production Balancing Methods

Abstract

Replacement of voidage relates to the method of injecting liquids to replace oil, water and gas inside the reservoir. The technique for voidage replacement is the volume of injected fluids in the barrel over the volume they got produced. Injected liquids may be wasted outside the floodable quantity of the pore in the reservoir during injection, because of many factors such as bad cement in the casing leakage, etc. A Voidage Replacement Ratio of 1.2 is chosen to preserve the replaced fluid pressure of the reservoir. The balancing Production technique relates to the determination of a scheduled rate of production to be accomplished at a particular time. To preserve the reservoir pressure, a production balancing ratio of 1.2 should be selected for a higher production rate that is balanced with the injected fluids. The balancing production approach involves ensuring that the liquids injected fulfil the production ability needed to prevent any reservoir pressure unbalance. The water alternating gas (WAG) method is the technique to improve oil recovery by injecting water to enhance sweep effectiveness. If gas is being injected into this technique, the viscosity of the oil will be reduced, making it convenient for the water to sweep it well into the production wells. WAG-365 case of a 365-day cycling period is the best one to be selected as longer time provides the gas with the opportunity to guarantee two things, sweeping the residual oil that is immobile and trapped inside the tight pores and also dissolving in the oil and reducing its viscosity. CO2 sequestration relates to the subterranean CO2 injection method to prevent the atmosphere from CO2 emissions from burning fossil fuels that subsequently lead to global warming and hazardous climate change. Throughout the WAG method, CO2 is used and injected to be stored as a solution and the quantity of CO2 stored is defined by changing the solubility of the gas. The more the gas's solubility results in a large quantity of stored CO2.