| 基于CT扫描技术的低渗油藏水敏效应后微观孔隙结构特征 |
| |
| 引用本文： | 胡心玲,雷浩.基于CT扫描技术的低渗油藏水敏效应后微观孔隙结构特征[J].地质科技通报,2023,42(2):178-185. |
| |
| 作者姓名： | 胡心玲 雷浩 |
| |
| 作者单位： | 中国石油化工股份有限公司江汉油田分公司勘探开发研究院, 武汉 430223 |
| |
| 基金项目： | 中国石油化工股份有限公司科研项目"新沟嘴组低渗透敏感性储层开发关键技术"P20069-5 |
| |
| 摘 要： | 为了研究水敏效应对低渗油藏微观孔隙结构特征的影响，将CT在线扫描技术和岩心驱替实验相结合，开展了低渗油藏不同渗透率岩心水敏性评价实验，对水敏过程中孔、喉半径分布特征、配位数、孔隙变化特征、物性参数变化及对储层渗流能力的影响进行了实验研究，并绘制了水敏前后极限注采井距对比图版。结果表明，随着渗透率降低，水敏效应对孔隙、喉道伤害程度越大、平均孔喉配位数减少越多。两者共同作用是造成储层启动压力梯度增加的主要原因；水敏效应对储层喉道伤害程度远大于对孔隙伤害程度；水敏效应造成黏土膨胀、颗粒运移几乎发生在所有孔隙中，但对岩心整体孔隙结构和分布特征影响不大。通过极限注采井距可知，水敏效应造成新沟嘴组低渗油藏极限注采井距减少了153 m，需要通过加密井来调整注采井距，改善注水波及范围。该研究结果对长期注水的水敏性低渗储层开发调整具有现场指导意义。
|
| 关 键 词： | CT扫描 低透油藏 水敏效应 微观孔隙结构 储层伤害 |
| 收稿时间： | 2021-08-29 |
Using CT scanning technology to investigate microscopic pore structure characteristics of low-permeability reservoir rocks after water sensitivity experiments |
| |
| Affiliation: | Research Institute of Petroleum Exploration and Development, SINOPEC Jianghan Oilfield Company, Wuhan 430223, China |
| |
| Abstract: | CT scanning and core flooding experiments were combined to investigate the change in microscopic pore structure of low-permeability reservoir rocks due to the water sensitivity effect. Water sensitivity experiments were conducted for low-permeability reservoirs using different permeability core plugs to study the pore throat radius distribution, coordination number, pore structure variation, physical property parameter variation, and effects on the seepage capacity. The comparison plates of the limit injection-production spacing were drawn. The results indicate that the pore throat damage increases while the mean coordination number decreases with the reduction of permeability, which leads to a higher flow resistance and a stronger damage to the microscopic pore structure. These combined effects lead to an increase in the starting pressure gradient. In addition, the damage extent of reservoir throats is much larger than that of pores in the reservoir. Moreover, the swelling of clay minerals and the particle migration mostly present in the pore space due to the water sensitivity effect, which would hardly influence the whole pore structure and distribution feature of the core plug. Furthermore, according to the limit injection-production spacing plates, the limit injection-production spacing of the Xingouzuizu Formation low-permeability reservoir decreases by 153 m, which is caused by the effect of water sensitivity. The injection-production well spacing must be adjusted by the infill well, which can be used to improve the injected water swept volume. This research could provide certain practical guidance for the development adjustment of low-permeability reservoirs featuring the water sensitivity effect under a long period of waterflooding. |
| |
| Keywords: | |
|
| 点击此处可从《地质科技通报》浏览原始摘要信息 |
|
点击此处可从《地质科技通报》下载全文 |
|
