LIQUID LOADING IDENTIFICATION AND PREDICTION IN WATER-PRODUCING GAS WELL BASED ON TUBING CASING PRESSURE ANALYSIS

The main reason for the low production level is liquid accumulation in some low-efficiency wells in tight sandstone gas reservoirs in the Linfen gas field. In order to define the characteristic of liquid loading in in tight sandstone gas reservoirs in Linfen gas field, a numerical model for calculating and predicting the liquid loading amount according to the casing pressure were established, a criterion for identifying gas well liquid loading according to casing pressure were determined in combination with dynamic data in actual gas well production, and the rule of gas well liquid loading in the research area was analyzed. Results indicate that: The criterion for identifying liquid loading based on production performance was established, for the wells without choke in this research area, if the tubing-casing differential pressure is > 1.5MPa, there may be liquid loading in the gas well; The gas wells in the research area was divided into wells without liquid loading, wells with liquid loading and wells with liquid unloading; A prediction model of gas well liquid loading was established, instance analysis was carried out in combination with actual well data, the method was proved feasible. The findings of this study are important for understanding the rule of liquid loading in gas well in tight sandstone gas reservoirs and the efficient application of the corresponding drainage and gas recovery technology.