| 摘要: |
| 目的 页岩储层中的裂缝系统对CH4产量和CO2封存量有着重要的影响,不同的储层地质特征有其对应的最优压裂方案。对鄂尔多斯盆地延长组页岩储层人工裂缝参数对CO2封存和CH4开采的影响进行分析。方法 基于鄂尔多斯盆地延长组页岩储层地质条件建立了页岩基质-裂缝双孔双渗均质模型,分析CO2增强页岩气开采技术(CO2-ESGR)中人工裂缝半长、裂缝宽度、裂缝高度、裂缝间距和裂缝数量对CO2封存量和CH4产量的影响。结果 CO2封存量和CH4产量与裂缝半长、裂缝宽度和裂缝高度呈正相关,其中裂缝宽度的影响最大,从5 mm增加到25 mm时,最多可使CO2封存量和CH4产量分别增加112.69%和87.11%。裂缝间距和裂缝数量增加可提高CO2封存量和CH4产量,但水平井长度相同时裂缝数量增加对CO2封存量和CH4产量的影响幅度远大于裂缝间距,当裂缝数量从2条增加到6条,最多可使CO2封存量和CH4产量分别增加151.92%和137.81%。结论 在开发过程中,合理增加人工裂缝的半长、高度、宽度和数量,可以实现高效CO2封存和CH4开采。 |
| 关键词: CO2地质封存 页岩气 人工裂缝 数值模拟 CO2-ESGR |
| DOI：10.3969/j.issn.1007-3426.2024.02.014 |
| 分类号: |
| 基金项目:国家重点研发计划项目(2019YFE0100100)“多井组CO2-EWR与储层系统动态监测技术研究”；国家自然科学基金“CO2封存的地质结构透明化表征方法与埋存场地选址”(42141009)；海洋地质资源湖北省重点试验开放基金“超临界CO2对页岩层的地球化学作用机制研究”(MGR202003) |
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| Effects of artificial fracture parameters on CO2 sequestration and CH4 production in CO2-ESGR |
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LIU Siyu1, YANG Guodong1, HUANG Mian1, YIN Shuguo1, MA Xin2, BAO Qi3
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1. School of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan, Hubei, China;2.Hydrogeological Environmental Geological Survey Center, China Geological Survey, Baoding, Hebei, China;3. Unconventional Petroleum Research Institute, China University of Petroleum-Beijing, Beijing, China
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| Abstract: |
| Objective Fracture systems in shale reservoirs have an important impact on CH4 production and CO2 sequestration, and different geological characteristics of reservoirs have their corresponding optimal fracturing schemes. The study aims to investigate the effect of artificial fracture parameters on CO2 sequestration and CH4 production of Yanchang formation shale reservoirs in Ordos Basin. Methods Based on the geological conditions of shale reservoirs of Yanchang formation in Ordos Basin, a dual-porosity, dual-permeability homogeneous model was established to analyze the effects of artificial fracture half-lengths, fracture width, fracture height, fracture spacing, and the number of fractures on CO2 sequestration and CH4 production in CO2-ESGR. Results The results showed that fracture half-length, fracture width and fracture height were positively correlated with CO2 sequestration and CH4 production, among which fracture width had the greatest influence. When the fracture width increased from 5 mm to 25 mm, CO2 sequestration increased by 112.69% and CH4 production increased by 87.11% at most. Both fracture interval and fracture number increased CO2 sequestration and CH4 production. However, when the horizontal well length was the same, the increasing of fracture number had a far greater impact on CO2 sequestration and CH4 production than that of fracture interval. When the number of fracture increased from 2 to 6, CO2 sequestration increased by 151.92% and CH4 production increased by 137.81% at most. Conclusion sDuring the development process, strategically enhancing the half-length, height, width, and quantity of artificial fractures can facilitate efficient sequestration of CO2 and extraction of CH4. |
| Key words: CO2 sequestration shale gas artificial fracture numerical simulation CO2-ESGR |
