特种油气藏2023，Vol.30Issue(6)：128-134,7.DOI:10.3969/j.issn.1006-6535.2023.06.017
志丹油区长7页岩油储层CO2吞吐室内实验
Indoor Experiment on CO2 Huff-n-Puff in Chang7 Shale Oil Reservoir in Zhidan Oil Region
摘要
Abstract
In order to evaluate the oil displacement effect of CO2 huff-n-puff of shale oil reservoirs and the mobility of crude oil under different scales of pore throats,a natural core of Chang7 reservoir in Zhidan Oil Region of Yan-chang Oilfield was selected,based on high temperature and high pressure CO2 huff-n-puff in long cores and residual oil in short cores online NMR test experiments,and on the basis of evaluating the oil displacement effect,the mixed-phase state of CO2 and the displacement law at different pressure measurement points were analyzed,the effect of mixed-phase huff-n-puff was compared with that of non-mixed-phase huff-n-puff at nano-and micron-scale pore throats,and the mobility of crude oil in different scale spaces of shale oil reservoirs was evaluated.The study shows that the effect of CO2 non-mixed-phase huff-n-puff was poor,the pressure inside the core increase was not obvious,and the pressure affecting range is small;under the condition of injecting the same pore volume multipli-er,the recovery efficiency was increased by 8.24 percentage points compared with CO2 non-mixed-phase huff-n-puff;the production pressure difference in the first 2 cycles of CO2 mixed-phase huff-n-puff was large,the dis-tance between CO2 mixed-phase huff-n-puff intervals was long,and the characteristics of CO2 mixed-phase dis-placement were obvious;in the whole pore throat of the rock sample,the proportion of micron-level pores was low,and nano-and submicron-level pores were the the main contributor of the crude oil.The study results can provide an important reference for shale reservoirs to replenish formation energy and improve recovery efficiency.关键词
可动性评价/长岩心/在线核磁共振/CO2吞吐/志丹油区Key words
mobility evaluation/long core/online NMR/CO2 huff-n-puff/Zhidan Oil Region分类
能源科技引用本文复制引用
师调调,杜燕,党海龙,朱童童,刘双双,石立华,张佳琪..志丹油区长7页岩油储层CO2吞吐室内实验[J].特种油气藏,2023,30(6):128-134,7.基金项目
陕西省自然科学基础研究计划"页岩油储层微-纳米孔喉系统量化表征及对可动流体赋存状态控制机理研究"(2022JQ-290)、"致密砂岩储层微观孔喉结构及薄膜流动对渗吸规律的影响"(2023-JC-YB-423) （2022JQ-290）
