油气藏评价与开发 ›› 2025, Vol. 15 ›› Issue (4): 646-655.doi: 10.13809/j.cnki.cn32-1825/te.2025.04.014

• 方法理论 • 上一篇    下一篇

枯竭气藏盐膏岩盖层CO2封存密闭性评价研究

蒋贝贝1(), 刘佳波1(), 张国强1, 王栋1, 李颖1, 罗红文1, 周浪2   

  1. 1.西南石油大学油气藏地质及开发工程全国重点实验室,四川 成都 610500
    2.中国石油西南油气田公司工程技术研究院,四川 成都 610017
  • 收稿日期:2024-03-12 发布日期:2025-07-19 出版日期:2025-08-26
  • 通讯作者: 刘佳波(2001—),男,在读硕士研究生,主要从事CO2埋存技术研究。地址:四川省成都市新都区新都大道8号,邮政编码:610500。E-mail:2802865392@qq.com
  • 作者简介:蒋贝贝(1984—),男,博士,副教授,主要从事页岩油测井数据处理与解释方面的研究工作。地址:四川省成都市新都区新都大道8号,邮政编码:610500。E-mail:jiangswpu1607@163.com
  • 基金资助:
    四川省面上基金项目“枯竭气藏CO2封存盖层封闭演化机制及评价方法”(2022NSFSC0192)

Research on sealing performance evaluation of CO2 storage in salt-gypsum caprocks of depleted gas reservoirs

JIANG Beibei1(), LIU Jiabo1(), ZHANG Guoqiang1, WANG Dong1, LI Ying1, LUO Hongwen1, ZHOU Lang2   

  1. 1.State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, China
    2.Engineering Technology Research Institute, PetroChina Southwest Oil & Gasfield Company, Chengdu, Sichuan 610017, China
  • Received:2024-03-12 Online:2025-07-19 Published:2025-08-26

摘要:

在全球碳中和战略的背景下,以CO2为主的温室气体排放不断增加,对全球气候、生态系统和人类生活产生了不利影响。CO2地质封存是实现碳中和目标的重要技术手段,而盖层作为潜在封存构造的封堵屏障,其密闭性是关乎CO2长期甚至永久封存的关键。盐膏岩盖层具有低孔、低渗、稳定性好和高突破压力等优良特性,可作为CO2长期安全封存的盖层。然而,盐膏岩盖层与其他岩性盖层的物化性质存在较大差异,导致盐膏岩盖层CO2封存密闭性评价仍然面临挑战,亟须建立一种适用于盐膏岩盖层的CO2封存密闭性评价方法。首先,基于层次分析法,综合考虑盖层宏观指标、微观指标和突破压力等关键盖层密闭性影响因素,建立了盐膏岩盖层CO2封存密闭性评价指标体系,并划分了不同指标的4个优劣等级,得出各指标对盐膏岩盖层的密闭性影响权重。其次,结合模糊数学综合评价法,计算出盐膏岩盖层CO2封存密闭性评价总权值,形成了一套适合盐膏岩盖层的CO2封存密闭性综合评价方法。最终,以四川盆地高石梯—磨溪区块为例,系统评价了这一潜在枯竭气藏盐膏岩盖层的CO2封存密闭能力,发现高石梯—磨溪构造气藏盖层密闭性评价总权值为[2.5,3.0),评价等级为“较好”,说明具备较好的CO2封存能力,适合未来开展CCS(碳捕集与封存)技术应用。研究成果可为盐膏岩盖层枯竭气藏CO2埋存选址及封存安全评价提供一定的技术指导。

关键词: 四川盆地, 枯竭气藏, 盐膏岩盖层, CO2封存, 密闭性评价

Abstract:

In the context of the global carbon neutrality strategy, greenhouse gas emissions —mainly CO— are continuously rising, exerting adverse effects on the global climate, ecosystems, and human life. Geological storage of CO2 is an important technological approach to achieving carbon neutrality targets. As sealing barriers within potential storage formations, the sealing property of caprocks is crucial for the long-term or even permanent CO2 storage. Salt-gypsum caprocks exhibit favorable properties such as low porosity, low permeability, high structural stability, and high breakthrough pressure, making them promising candidates for long-term and secure CO2 storage. However, their physicochemical characteristics differ significantly from those of other lithological caprocks, posing challenges to evaluating their sealing performance for CO2 storage. Therefore, there is an urgent need to establish an evaluation method tailored to salt-gypsum caprocks. Firstly, based on the Analytic Hierarchy Process (AHP), a comprehensive evaluation index system was developed by considering key influencing factors, such as macro indicators, micro indicators, and breakthrough pressure, affecting the sealing performance of caprocks. Four grading levels were defined for each index, and the influence weight of each index on the sealing performance of salt-gypsum caprocks was determined. Secondly, by integrating the Fuzzy Comprehensive Evaluation Method, the total weight for evaluating the sealing performance of salt-gypsum caprocks for CO2 storage was calculated. This resulted in the development of a comprehensive evaluation method of CO2 storage sealing tailored to these types of caprocks. Finally, the method was applied to the Gaoshiti-Moxi block in the Sichuan Basin as a case study, where the CO2 storage sealing performance of its potential salt-gypsum caprock in a depleted gas reservoir was systematically evaluated. The results revealed that the total weight of the sealing performance evaluation of Gaoshiti-Moxi structural gas reservoir caprocks ranged from [2.5,3.0), corresponding to a grade of “relatively good”, indicating a relatively strong capacity for CO2 storage. This suggested the site was suitable for the future application of Carbon Capture and Storage (CCS) technology. The research results can provide technical guidance for site selection and storage safety evaluation of CO2 storage in depleted gas reservoirs with salt-gypsum caprocks.

Key words: Sichuan Basin, depleted gas reservoir, salt-gypsum caprocks, CO2 storage, sealing performance evaluation

中图分类号: 

  • TE34