低渗透气藏开发机理研究进展

Research progress in the development mechanism of low-permeability gas reservoirs

我国低渗透气藏处于开发早期,尚有许多机理问题有待研究解决。通过对当前研究较多的气水渗流机理、储层应力敏感性、非均质储层供气机理等进行总结分析后认为:我国低渗透气藏大多是陆相沉积储层,孔隙结构复杂,非均质性强,孔隙内气水分布与渗流机理复杂,存在低速非线性渗流特征;不同地区、不同类型储层岩石应力敏感特征不同,储层应力敏感性对气藏开发的影响及其在实际生产中的表象还需要进一步加强研究;依据储层地质特征建立的非均质储层供气动态物理模拟方法,为研究分析不同渗透性储层区域的供气机理和能力提供了手段,也为研究非均质低渗气层的动用条件,预测低渗透气藏的动用程度以及优化井网部署、气井配产、产能预测等提供了理论基础和技术依据。

In China,the development of low-permeability gas reservoirs is still at the early stage.Therefore,many issues of mechanisms await solutions.After summarizing and analyzing the gas/water flow,stress sensitivity and seepage mechanism of heterogeneous reservoirs,we have drawn the following conclusions: the low-permeability gas reservoirs in China are featured mostly by continental sedimentary,complex pore structures and distribution of gas/water,strong heterogeneity,and non-linear seepage.Characteristics of stress sensitivity are different in different districts and with different types of rocks.The influence of stress sensitivity on the development of gas reservoirs and its representations in practice need further study.Dynamic physical simulation of gas supply in a heterogeneous reservoir based on its geological features provides methods for studying and analyzing the mechanisms and capability of gas supply at different-permeability strata of a gas reservoir.Meanwhile,it also provides theoretical and technical foundations for studying the development conditions of heterogeneous gas reservoirs,predicting the gas producing reserves with low permeability,and optimizing the gas well networks,production proration and productivity prediction,etc..