低渗透气藏含启动压力的二次幂指数方程及应用

Second exponential equation with start-up pressure for low permeability gas reservoirs and its application

李红伟 刘慧卿 王厉强 杨志国 申红

LI Hongwei LIU Huiqing WANG Liqiang YANG Zhiguo SHEN Hong

中国石油新疆油田分公司陆梁油田作业区，新疆克拉玛依　834000 中国石油大学石油天然气工程学院，北京　102249 中国石油吐哈油田分公司博士后工作站，新疆哈密　839009 中国石油大学博士后科研流动站，北京　102249 中国石化胜利油田分公司地质科学研究院，山东东营　257061

Luliang Oilfield Operation Area, Xinjiang Oilfield Company, Karamay 834000, China College of Petroleum Engineering, China University of Petroleum, Beijing 102249, China Post-Doctoral Station in Tuha Oilfield Company, Hami 839009, China Post-Doctoral Mobile Station in China University of Petroleum, Beijing 102249, China Research Institute of Geosciences, Shengli Oilfield Company, SINOPEC, Dongying 257061, China

低渗透气藏考虑启动压力梯度的拟稳态或稳态三项式产能方程虽较二项式产能方程有较大改进，但待定参数的确定随意性较大，且建立的三项式产能方程的表达形式不唯一，计算的无阻流量也不唯一。为克服上述缺陷，从径向流两区渗流物理模型出发，建立了含启动压力的二次幂指数产能方程，并结合实例对比了该方法与原方法的优劣。结果表明，该方法简便可靠，待定参数和方程形式唯一确定；此外，三项式产能方程所计算无阻流量偏于乐观，矿场生产中建议采用含启动压力的二次幂指数产能方程计算无阻流量值。

The pseudo-state or steady state trinomial cube deliverability equation considering the start-up pressure gradient has been improved largely compared with the binomial cube equation in low permeability gas reservoirs, but the flexible of parameters determination is great. In addition, the expression of trinomial cube deliverability equation is not unique and so does the resulted open flow capacity. A deliverability equation with the start-up pressure based on the radial flow physical model in two areas has been established to overcome these shortcomings. And then the new method has been verified and compared with the original one through specific examples. The results show that this method is simple and reliable, the unknown parameters and the form of equations are capable of being ascertained. In addition, the open flow capacity calculated using the trinomial cube deliverability equation is optimistic, so that the open flow calculated with this method is proposed in mining production.