碳酸盐岩高压高产气井异常产能资料解释方法

Explanation of Abnormal Productivity Data Regarding Carbonate High-Pressure, High-Productivity Gas Well

塔X01井是在塔中北坡缝洞型碳酸盐岩储层发现的第一口高产气井,由于特殊的储层特征,压力计难以下至储层中部,造成压力资料品质很差,影响了产能的准确评价。利用前人对气液两相垂直井筒压力研究成果,对异常资料进行甄别,形成生产数据计算并校正出井底压力方法,计算误差0.2%。基于Firoozabadi和Katz理论,建立了考虑高产时气体高速脉冲流动的碳酸盐岩高压高产气井产能方程,利用约束优化算法对其进行求解,并进行了实例应用,结果表明,该井无阻流量比常规方法计算小10%左右。获得的三项式产能方程及其求解方法,更符合研究区的矿场实际。

The TX01well is the first high-productivity gas well found in the fractured carbonate reservoir formation in the North Slope of the central Ta area.Owing to the special characteristics of the reservoir,it is difficult to insert the pressure gauge down to the middle of the reservoir,resulting in poor quality of pressure data,which consequently affects the accuracy of the production capacity evaluation.Based on previous research on the vertical wellbore pressure of gas-liquid two-phase systems,the abnormal data were screened and the production data were obtained.A method to calculate and calibrate the bottom-hole pressure,with a calculation error of0.2%,was proposed.Based on the theory of Firoozabadi and Katz,a productivity equation for the high-pressure,high-productivity carbonate gas well,considering the high-velocity pulsed flow of gas at high-productivity,was established.Based on the constraint optimization algorithm,the solution was obtained,and applied to a real case study.The results show that the open flow of this gas well was approximately10%smaller than the result from the conventional method.The obtained three-term productivity equation and its solution method are more in line with field practice in the study area.