评价异常高压高产气井产能的新方法

A new method for evaluating the productivity of abnormally high-pressured and high-rate gas wells

在塔里木盆地的DABEI地区,由于复杂的地质构造运动和地层的压实作用,形成了许多受断层控制的异常高压高产气藏;气井多点测试资料的实际应用表明,传统的二项式对该地区异常高压高产气井的产能评价是不适用的,但异常高压高产气井的生产压差与产量之间却存在很好的直线关系。对于这一直线关系,本文进行了有效的理论推导。基于井处边部或中央的断块气藏模型,利用达西定律的线性层流和水电相似原理的等值渗流阻力法,建立了井底流压与产量的无因次IPR方程,在此基础上,提出了利用单点测试资料确定绝对无阻流量和IPR曲线的新方法。实际应用表明,本文提供的方法实用有效。

Due to complex geological tectonic movement and compaction of strata, many abnormally high-pressured and high-rate gas reservoirs controlled by faults have been formed in DABEI area of Tarim basin. The practical application of multi-point test data of gas wells shows that traditional quadratic equation is not applicable to the productivity evaluation of abnormally high-pressured and high-rate gas wells in this area, but there is a good linear relationship between the production pressure difference and production of abnormally high-pressured and high-rate gas wells. In view of this linear relationship, a valid theoretical derivation is made in this paper. Based on the fault-block gas reservoir models of the well in center reservoir or at the edge, the dimensionless IPR equation for bottom flow pressure and production is established by using the equivalent seepage dynamic resistance method of linear laminar flow of Darcy’s law and water-electricity similarity principle. On this basis, a new method for determining the absolute open flow potential and IPR curve using single-point test data is proposed. The practical application shows that the method proposed in this paper is practical and effective.