Analytical Study for Recovering Lost Condensate and Sensitivity Analysis for Production Optimization of a Gas Condensate Reservoir

Sensitivity analysis study for production optimization and recovery of lost condensate with gas-injections play vital role in enhancing-condensate recovery during the field development to yield optimum profit. In gas cycling, gas is effectively miscible with condensate and its viscosity is reduced, which eventually decreases the residual-condensate-saturation and recovers the lost condensate with an optimum gas production. In this work simulation of the single-layer heterogeneous–gas condensate reservoir was modeled in a compositional simulator to highlight the reservoir and fluid properties characteristics. Then a production development study of gas cycling and CO2 injection was analyzed to understand which method is the most optimal and economically feasible to recover the lost condensate and increase the ultimate productivity yield. An injection patterns study of five-spot and nine-spot with gas cycling has been carried out with the analysis of impact of injection patterns on enhancing-condensate recovery and optimizing the project economically. Nineteen years of gas cycling applied with five-spot and nine-spot pattern flooding improved condensate recovery by 41%. The results also proved that the selection of optimum well spacing can help to best select flooding pattern in order to optimize a field development plan for the gas condensate reservoir. Here, an in-depth sensitivity study for the production optimization of gas cycling five-spot with optimum well spacing plans was introduced; CapEx for drilling number of injection-production wells is the influencing factor found in this study. The relationship between well spacing and number of wells was also studied to evaluate the impact of the applied capital expenditure (CapEx) and operating expenditure (OpEx) upon the Net Present Value (NPV) with optimal injection pressure, injection flow-rate, and production time.