致密油藏压裂水平井分区渗流模型及产能分析

Partition seepage model and productivity analysis of fractured horizontal wells in tight reservoirs

谢斌 姜景耀 贾久波 任岚 黄波 黄鑫2

中国石油新疆油田分公司工程技术研究院，新疆 克拉玛依 834000 西南石油大学油气藏地质及开发工程国家重点实验室，四川 成都 610500

Research Institute of Engineering Technology, Xinjiang Oilfield Company, PetroChina, Karamay 834000, China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China

针对致密油藏水平井缝网压裂后形成的复杂破碎改造体，基于分形双重介质模型建立了考虑渗透率孔隙度非均匀分布的致密油藏分区渗流数学模型，并引入裂缝复杂指数表征改造体的改造程度，利用Laplace变换和Stehfest数值反演对数学模型进行解析求解，利用矿场数据验证了模型的可靠性，并对产能影响因素进行了分析。研究结果表明：裂缝半长和裂缝条数的增加对全生产周期水平井产量有明显提升，但存在一个经济最优值；储层外边界反映了水平井的有效控制范围，对致密油井中后期产量的提升有明显的影响；改造区窜流系数越大，中期产量越高，产量递减越缓慢；弹性储容比越大，致密油井高产阶段持续时间越长。

Considering the complex fractural reconstruction zone after SRV treatment in tight reservoir, a mathematical model of the seepage flow in a tight reservoir is established based on the fractal dual medium model and the reconstruction degree therein is characterized by the complex index of fracture. The mathematical model is solved analytically by using the Laplace transform and Stehfest numerical inversion, the reliability of the model is verified by the field data, and the factors affecting the productivity are analyzed. The results show that the increase of half-length and numbers of fracture can obviously improve the production of horizontal wells in the whole production period, but there is an economic optimal value; the outer boundary of the reservoir reflects the effective control range of the horizontal well, which has an obvious influence on the increase of the production in the middle and late stage of the tight well; the higher the channeling coefficient, the higher the medium production in the middle period, the slower the yield decrease; the higher the ratio of the elastic storage capacity, the longer the duration of the high yield phase of the tight well.

10.6056/dkyqt201903011