大庆油田致密油井大规模压裂后CO_(2)吞吐技术研究与现场试验

Study and field test of CO_(2) huff and puff technology in tight oil wells of Daqing Oilfield after large scale fracturing

大庆外围扶余致密油层物性差,水驱受效差,压裂后无能量补充,产量递减快。为了补充地层能量,保证压裂后开发效果,开展了CO_(2)吞吐技术研究。从CO_(2)增产的主控机理入手,通过驱油核磁检测实验确定了CO_(2)吞吐动用孔隙下限,利用三维高温高压大模型物模实验研究了CO_(2)吞吐动用规律,通过数值模拟优化了选井原则和工艺参数设计标准。自2016年以来,已开展矿场试验16口井,阶段累计增油量为14074.5t,提高阶段采收率2.41%,为提高致密油开发效果提供了技术支持。

Due to poor physical properties,poor water flooding effect,no energy supplement after fracturing,and quickly decline production in Fuyu tight reservoir in the periphery of Daqing,the study on CO_(2)huff and puff technology has been carried out in Fuyu tight reservoir,so as to supplement the formation energy and ensure the development effect after fracturing.Starting from the main control mechanism for CO_(2)stimulation,the lower limit of pores for CO_(2)huff and puff volume was determined by the nuclear magnetic detection experiment of oil displacement.The producing law by CO_(2)huff and huff was studied by the 3D HTHP physical model experiment,and the principle of well selection and the design standard of process parameters were optimized by numerical simulation.Since 2016,16 wells tests have been carried out at well site;the cumulative incremental oil was 14074.5 t during one stage and the enhanced oil recovery was 2.41%,which provided technical support for improving the development effect in tight oil reservoir.