古龙页岩油高温高压注CO_(2)驱动用效果  

Producing effect of CO_(2) displacement injection at high temperature and high pressure for Gulong shale oil

作　　者：李斌会 邓森[1,2,3] 张江 曹胜[1,2,3] 郭天娇 徐全[1,2,3] 霍迎冬 LI Binhui;DENG Sen;ZHANG Jiang;CAO Sheng;GUO Tianjiao;XU Quan;HUO Yingdong(National Key Laboratory for Multi-resource Collaborated Green Development of Continental Shale Oil,Daqing 163712,China;Exploration and Development Research Institute of Daqing Oilfield Co.,Ltd.,Daqing 163712,China;Heilongjiang Provincial Key Laboratory of Reservoir Physics&Fluid Mechanics in Porous Medium,Daqing 163712,China)

机构地区：[1]多资源协同陆相页岩油绿色开采全国重点实验室,黑龙江大庆163712 [2]中国石油大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712 [3]黑龙江省油层物理与渗流力学重点实验室,黑龙江大庆163712

出　　处：《大庆石油地质与开发》2024年第1期42-51,共10页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家科技重大专项“大庆古龙页岩油勘探开发理论与关键技术研究”(2021ZZ10)。

摘　　要：为了明确古龙页岩油高温高压注CO_(2)驱动用效果,首先根据页岩压汞和氮气吸附实验结果,给出页岩T2值与孔喉半径转换系数,根据饱和页岩的T2谱特征,将页岩孔隙分为小孔、中大孔和页理缝;然后通过计算页岩油采出程度,考察吞吐周期、闷井时间、裂缝对吞吐驱油效果的影响,并且分析吞吐后岩心孔隙结构的改变程度;最后对比页岩油CO_(2)吞吐和CO_(2)驱替的驱油效果,并给出最优的驱油方式。结果表明:吞吐动用幅度最大的是中大孔和页理缝中的页岩油,小孔中的页岩油采出程度最低,增加闷井时间,页岩油采出程度仅提高0.81百分点,压裂可以使小孔中的页岩油采出程度提高11.33百分点,使小孔中的页岩油得到有效动用;吞吐比驱替可以使页岩油采出程度提高30.98百分点,并且可以动用干岩样中的页岩油,效果优于驱替;驱吞结合驱油方式比只进行吞吐可以使页岩油采出程度提高12.88百分点以上,并且可以大幅度提高小孔中页岩油的采出程度;吞吐后岩心孔隙结构发生明显变化,页岩砂砾含量不同是导致页岩吞吐前后孔隙结构变化差异大的重要原因。研究成果可为古龙页岩油矿场实践提供重要的基础参数。In order to clarify the effectiveness of CO_(2) injection at high temperature and high pressure for Gulong shale oil,the conversion coefficient between shale T2 value and pore throat radius is firstly given based on the re⁃sults of shale mercury injection and nitrogen adsorption experiments.Shale pores are divided into small pores,medi⁃um-large pores and lamellation fractures based on T2 spectrum characteristics of saturated shale.Then,through cal⁃culating shale oil recovery of OOIP,the effects of huff and puff cycle,soak time and fractures on huff and puff dis⁃placement effect are examined,the degree of change in core pore structure after huff and puff is analyzed,and final⁃ly the effects of shale oil CO_(2) huff and puff and CO_(2) displacement are compared,providing optimal displacement method.The results show that shale oil in medium-large pores and lamellation fractures has the maximum producing degree,while shale oil in small pores has minimum recovery of OOIP.Increasing the soaking time only increases shale oil recovery by 0.81 percentage points,and fracturing increases shale oil recovery in small pores by 11.33 per⁃centage points,effectively producing shale oil in small pores.Huff and puff can increase shale oil recovery by 30.98 percentage points of displacement,and can produce shale oil in dry rock samples,with better effects than displace⁃ment.Combining displacement and huff and puff can increase recovery of OOIP by more than 12.88 percentage points compared to only using huff and puff,and can significantly increase recovery of shale oil in small pores.Pore structure of the cores undergoes significant changes after huff and puff,and the difference in shale gravel content is an important reason for the significant differences in pore structure changes before and after shale huff and puff.The experiment results provides important basic parameters for field practice of Gulong shale oil.

关 键 词：古龙页岩油 孔隙结构 CO_(2)驱替 CO_(2)吞吐 高温高压 核磁共振 

分 类 号：TE357[石油与天然气工程—油气田开发工程]