Experimental Study on Reducing Water Phase Trapping in Tight Gas Reservoirs

This document explains and demonstrates how to reduce water phase trapping in tight gas reservoirs during drilling. The water phase trapping laboratory device and experiment method has been studied, through the experiments on reservoir water phase trapping of western Sichuan Basin in China, Knowing that the damage is very serious, water self absorption experiments with different periods show that porosity and permeability of cores are basically above 50%. for the reason, the high capillary pressure and low water saturation are the main factors. Water phase trapping damage prevention measures has been put forward, including avoiding using water-based operating fluid as much as possible, minimizing or even avoiding the invasion of water-based operating fluid, and reducing interfacial tension and promote smooth operating fluid flow back.