The Application of Well Testing in Water Encroachment Discrimination of KL2 Water-Bearing Gas Reservoir

The High-pressure gas reservoirs and high-pressure gas condensate reservoirs make up 20% of the proved natural gas reserve and 72% of the proved oil condensate reserve of China. Effective, stable and safe development of these reservoirs is of great strategic significance to the reliable, safety gas supply of the West-to-East Transmission initiative as they contribute 17.5 billion cubic meters of gas or 21% of the nation’s total natural gas production.KL2 is a large, self-contained, hyper-pressure edge-bottom-water dry gas reservoir rarely found in the world, featuring high gas column, anomalous pressure and high per-well productivity. So far, five wells there have reported water flows, though the productivity of the gas reservoir and wells are decreasing a little as a result of stress sensitivity and gas-water flow in the gas pays. This paper presents a wellhead pressure-coupled model established based on the extensive wellhead and underground test data recorded for KL2, examines the effects of water encroachment on the typical well test curves, and validates the method by using it to analyze and quantify the edge-bottom water dynamics of KL2.