Drawdown Management Optimization from Time-Lapse Numerical Simulation

Abstract The Choke Management has been one of the "hot topics" in Unconventional Reservoirs since the negative impact in using an accelerated flowback has been demonstrated in many documented cases. Modern production practices have migrated from a Choke Management to a Drawdown Management Strategy to improve the control on the effective net stress over the proppant in order to prevent hydraulic fracture conductivity damage and maximize ultimate recovery. The strategy optimization is a complex problem that reservoir engineers are still trying to solve using different tools from empirical observations up to complex reservoir simulators that includes reservoir physics and the most advanced rock mechanics. This work contributes introducing an innovative workflow using a state of the art non-coupled numerical simulator, with the addition of time-steps one-way coupled calculations. The methodology consists in using a commercial reservoir simulator to History Match Completion Treatment Pressures and then Production. Once this first step has been completed, a Pore Pressure Grid is extracted at different times and then used to calculate changes in the minimum stress according to the isotropic poroelastic equation. Finally, the effective net stress over the proppant is calculated. This process is repeated with different Drawdown Management Strategies until the optimization. The complete workflow is introduced in a real case example where a robust dataset was available for a horizontal well. Finally, some assumptions and considerations are discussed and conclusions are extracted from this study.