超高压气藏改建储气库注采能力及库容评价——以川东北清溪储气库为例

Injection-productivity and storage capacity evaluation for rebuilding gas storage based on ultra-high pressure gas reservoir: a case study of Qingxi gas storage in Northeast Sichuan

张俊法,曾大乾,张广权,杨小松,糜利栋

ZHANG Junfa, ZENG Daqian, ZHANG Guanquan, YANG Xiaosong, MI Lidong

中国石化石油勘探开发研究院，北京 100083

Petroleum Exploration and Production Research Institute, SINOPEC, Beijing 100083, China

超高压气藏储层欠压实，具有较强的应力敏感性（又称压敏效应），在其改建储气库注采能力和库容评价时，常规方法不适用。为此，文中以川东北清溪储气库为例，开展了超高压裂缝￣孔隙型碳酸盐岩气藏压敏实验，并基于实验结果，利用拟稳定渗流原理，修正产能方程系数，建立了考虑压敏效应影响的二项式产能方程；在此基础上，利用节点分析方法，以冲蚀流量和临界携液流量为约束条件，评价了储气库在不同地层压力下的注采能力；同时，建立了综合考虑岩石压缩系数连续变化的超高压气藏物质平衡方程，准确评价储气库在不同地层压力下的有效库容，形成了超高压气藏改建储气库库容参数优化设计技术，为同类气藏改建储气库提供了技术支撑。

Ultra-high pressure gas reservoir has a strong stress sensitivity(pressure-sensitive effect) because of its undercompaction. The conventional method is not applicable to injection-productivity and storage capacity evaluation for rebuilding gas storage. Therefore, taking Qingxi gas storage as example in Northeast Sichuan, pressure-sensitive experiment of fractured-porous carbonate reservoir with ultra-high pressure was carried out. Based on the experimental reslults, the coefficient of productivity equation is modified by using the pseudo stable seepage principle, and binomial productivity equation considering pressure-sensitive effect is established. According to the new productivity equation, taking erosion rate and critical fluid carrying rate as constraint condition, the injection-production capacity under different formation pressures are evaluated by nodal analysis method. At the same time, the material balance equation of ultra-high pressure gas reservoir considering the continuous variation of rock compressibility is established, and the effective storage capacity under different formation pressures are accurately calculated. The optimization design technology of storage capacity parameters of gas reservoir with ultra-high pressure is built, which provides technical support for rebuilding gas storage of similar gas reservoir.

10.6056/dkyqt202106011