Integrity Evaluation Method of Completion Screen in Deepwater Gas Reservoirs with High Temperature and High Pressure

Abstract

AbstractIn deepwater, high-temperature and high-pressure gas reservoirs, the failure modes of screens are affected by a variety of bottom-hole environments, including water production, CO2 gas, sand production, high temperature, high production and high speed and other conditions. Among them, under the conditions of water production and CO2 gas, the corrosion damage of the metal screen is the main failure mode; under the condition of sand production, the screen medium is more likely to cause clogging and failure resulting in reduced production; high temperature conditions are the main factors affecting the accuracy of the screen; Under the production conditions of high output and high flow rate screens are more prone to erosion damage caused by gas carrying sand. By analyzing the failure modes of screens in high-temperature and high-pressure gas reservoirs under different bottom hole environments, the comprehensive conditions of the screens are simulated to evaluate the comprehensive performance of the screens. Based on the experimental simulation results, and mainly considering the dynamic changes of corrosion, erosion, clogging, sand retaining, accuracy change, etc., a comprehensive simulation method for screens in high-temperature and high-pressure gas reservoirs is established. In this paper, taking a gas field in South China Sea as an example, according to each individual simulation method and index system, the integrity of sand control screens are evaluated, and sand control methods and parameters are finally selected based on the evaluation results. This method can predict the high temperature accuracy change of the screen medium and the sand retaining effect, the blockage of the screen medium and the reduction of production, the dynamic condition of the screen corrosion and the damage condition of the screen erosion. Integrity evaluation is of great significance for improving the sand control effect and production efficiency of deepwater gas reservoirs with high-temperature and high-pressure.KeywordsIntegrity evaluationScreenDeepwaterCompletionSand control