Study On Performance Of Water-Producing And Water-loading In Gas Well

With development of gas field, the number of water-producing gas wells will gradually increase, and the water will have greater impact on the production rate. How to extend the water free production period is significant to the water free gas wells. However, preventing and controling the water loading is important to the water- producing gas wells.This paper is focused on how to solve the mentioned problems. It researches the mechanism of water producing in the gas well, including the source of water, the trend of water producing, the impact on rate, as well as measures for controlling water loading. Then it summaries the methods to calculate the bottom hole pressure for gas wells of different types .While the diliverability equation for water-producing gas well is derived by using pseudopressure, compared with monophase diliverability equations. Combined with past methods, the model for calculating producing water critical rate is established and solved on the basis of water coning mechanism and gas reservoir characters. The model can analyze the shape of water cone at different gas rate and how producing water critical rate varies with different parameters. Another model which can judge and predict the water loading in gas well is established after water loading process study. It can judge water loading of gas well with different GWR by using critical carrying water rate, and predict production performance while water loading. The results of this model can be used to optimize the tubing. The models and methods above provide theoretical basis and guidance for production decision in gas field.