Study On Production Dynamics Of CL Gas Field

Volcanic gas reservoir in CL gas field YCZ group, which was characterized by active bottom water, abundant fractures, high concentration of CO2, large differences in well’s productivity and controlled reserves. As a result, problems such as research on water influx dynamics law, controlled reserves verification, and reasonable production allocation still need to be addressed. By means of analyzing production performances for each gas wells, as well as studying the reservoir pressure changes and productivities, the direction of gas reservoir water influx and changes of gas-water interface have been calculated based on the gas reservoir numerical simulation method, which can provide reasonable suggestions and guidance for gas field development. The main contents are as follows:(1) This paper developed a distinguished standard between condensate water and formation water of YCZ gas reservoirs, and gas wells are divided into three classes including gas well producing condensate water, gas well producing formation water and liquid signs gas well.At last, different types of gas production dynamic characteristics are analyzed.(2) This paper studied the invasion dynamic chracteristics as well as water intrusion models for wells producing water. Combined with the results of gas reservoir numerical simulation, the direction of gas reservoir water influx has been given and the current air-water interface has been predicted.(3) On the basis of the Everdingen-Hurst model, water influx models for both of the homogeneous layered bottom water gas reservoir and dual media edge water gas reservoir were established and solved respectively. In addition, the influence of some parameters on the dimensionless water influx curve tendency has been analyzed.(4) This paper improved the material balance equation of water drive gas reservoir, by means of which an innovated method to calculate the amount of gas reservoirs water influx has been proposed. Water influx energy was evaluated by water flooding index and water body multiple.(5) This paper has utilized a variety of methods to predict the current average formation pressure and to calculate controlled reserves of each gas well.(6) YCZ gas wells deliverability testing data were interpreted to predict the absolute open flow of current gas wells and the reasonable production allowcations for each gas well were calculated.