Optimizing Hydraulic Fracture to Manage Sand Production by Predicting Critical Drawdown Pressure in Gas Well

摘要

Sand control by hydraulic fracturing in high permeable gas formation is becoming an increasingly popular completion option. This improves the well's productivity as well as manages the sand production. So, optimizing the treatment parameters for hydraulic frac turing, which can prevent most unfavorable effects, one of them being sand production, is now a critical process to be programmed systematically with all realistic design con straints. This paper describes the development of an integrated program with global opti mization algorithms that optimize all treatment parameters simultaneously; maximizing objective function (net present value) and satisfying newly modeled design constraints. These constraints are formulated as functions of treatment parameters, fracture geome try, and mechanical and petrophysical properties of the reservoir, so that the critical con ditions that induce sand production and other unfavorable effects do not become active. One of the important constraints is the critical drawdown pressure (CDP) relating to sand production. A genetic-evolutionary computing algorithm is integrated to solve the constrained treatment design problem that it finds optimum values for treatment parame ters and fracture geometry that are formation compatible. The capability of the inte grated model is demonstrated by application to a hypothetical gas reservoir and predicting the production and CDP over a number of years, helping sand control. When compared with the proposed model, the traditional model violates some important con straints.