气井产能确定新方法

NEW METHODS OF DETERMINING GAS WELL PRODUCTIVITY

新疆温吉桑地区温八块凝析气藏属低孔、低渗 ,非均质性较严重气藏 ,试井测试资料较少 ,常规的产能确定方法 (如利用试井资料确定产能方程 ,采气指数法或一点法 )应用较困难 ,文章从气井渗流理论出发 ,以二项式产能方程为基础 ,对气井渗流方程进行了分析研究 ,结合温吉桑温八块凝析气藏具体情况 ,提出新的气井产能确定方法———单位平方地层压力无阻流量法及单位地层系数采气指数法 ,并进行了实例计算 ,最后结合气井连续排液条件和数值模拟结果 ,遵循一定的配产原则 ,确定了该区块的气井合理产能和配产指标 ,为开发方案的编制和实施提供了理论依据和技术支持 ,深化了气藏工程的研究 ,这些方法可以推广应用于其它气藏或凝析气藏。

The Wenbakuai condensate gas reservoir in Wenjisang region,Xinjiang Province,belongs in a low-porosity,low-permeability and seriously heterogeneous reservoir.Because of lacking of well testing data,it is difficult to use the conventional methods,such as the productivity equation determined by well testing data and gas productivity index method or one-point method,etc.,to determine productivity.According to gas well percolation flow theory,a gas well productivity equation is analyzed on the basis of the binomial productivity equation;the new methods of determining gas well productivity,i.e.open-flow capacity per unit square formation pressure method and gas productivity index per unit formation conductivity method,are proposed;and an example is taken for calculating by these methods in the paper.Finally,in combination with gas well serial fluid draining and numerical simulation,the reasonable productivities and proration indexes of the gas wells in the region are determined in accordance with a certain proration principles,which provides a theoretical basis and technical support for drawing up and implementing development plan and deepens the research on gas reservoir engineering.These methods may be popularized and applied to the other gas reservoirs or condensate gas reservoir.