Evolution of rock mass stress, movement, and deformation during injection-production processes in coal mines that have been converted into natural gas storage facilities

IF 3.3 2区 工程技术 Q3 ENERGY & FUELS
Xuejie Deng , Xiaoming Shi , Zhide Wu , Yuan An , Jichu Wang , Shicong Li , Xifeng Liang , Benjamin de Wit
{"title":"Evolution of rock mass stress, movement, and deformation during injection-production processes in coal mines that have been converted into natural gas storage facilities","authors":"Xuejie Deng ,&nbsp;Xiaoming Shi ,&nbsp;Zhide Wu ,&nbsp;Yuan An ,&nbsp;Jichu Wang ,&nbsp;Shicong Li ,&nbsp;Xifeng Liang ,&nbsp;Benjamin de Wit","doi":"10.1016/j.gete.2025.100703","DOIUrl":null,"url":null,"abstract":"<div><div>The rapid growth in natural gas consumption globally has been accompanied by a significant demand increase for storage capacity. Abandoned underground coal mines can be converted into natural gas storage facilities with relatively low construction costs and short construction periods. However, the underground coal pillars and surrounding rock masses are at risk of movement and deformation under the dual effects of injection-production pressures and creep effect. By using mined-out areas of a selected coal mine as the setting to examine performance and effectiveness, this study preliminarily proposes a simplified technical approach for converting abandoned room-and-pillar coal mines into natural gas storage facilities. Also, this study presents and interprets the rock movements, deformations, and fracture characteristics during the injection-production processes. The research shows that: (1) The initial deflection of the roof was 142.91 mm, it increased at a decreasing rate to 226.06 mm after 50 cycles. (2) After injection-production processes the stress and resulting displacement on pillars showed \"arched\" distributions. (3) As injection-production stress increased from 1.8 MPa to 8.2 MPa, the difference in vertical displacement between the roof and pillars decreased from 108.22 mm to 91.28 mm. The instability risk is found when the injection-production pressure approaches in-situ conditions. (4) More injection-production cycles increased the proportional number of fractures in the overlying rock mass, as well as the length and aperture of the fractures. The research findings provide theoretical underpinnings for the conversion of abandoned coal mines to gas storage facilities from engineering practices.</div></div>","PeriodicalId":56008,"journal":{"name":"Geomechanics for Energy and the Environment","volume":"43 ","pages":"Article 100703"},"PeriodicalIF":3.3000,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Geomechanics for Energy and the Environment","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2352380825000681","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 0

Abstract

The rapid growth in natural gas consumption globally has been accompanied by a significant demand increase for storage capacity. Abandoned underground coal mines can be converted into natural gas storage facilities with relatively low construction costs and short construction periods. However, the underground coal pillars and surrounding rock masses are at risk of movement and deformation under the dual effects of injection-production pressures and creep effect. By using mined-out areas of a selected coal mine as the setting to examine performance and effectiveness, this study preliminarily proposes a simplified technical approach for converting abandoned room-and-pillar coal mines into natural gas storage facilities. Also, this study presents and interprets the rock movements, deformations, and fracture characteristics during the injection-production processes. The research shows that: (1) The initial deflection of the roof was 142.91 mm, it increased at a decreasing rate to 226.06 mm after 50 cycles. (2) After injection-production processes the stress and resulting displacement on pillars showed "arched" distributions. (3) As injection-production stress increased from 1.8 MPa to 8.2 MPa, the difference in vertical displacement between the roof and pillars decreased from 108.22 mm to 91.28 mm. The instability risk is found when the injection-production pressure approaches in-situ conditions. (4) More injection-production cycles increased the proportional number of fractures in the overlying rock mass, as well as the length and aperture of the fractures. The research findings provide theoretical underpinnings for the conversion of abandoned coal mines to gas storage facilities from engineering practices.
煤改储气设施注采过程中岩体应力、运动和变形演化
随着全球天然气消费量的快速增长,对储存能力的需求也大幅增加。废弃的地下煤矿可以改造成天然气储存设施,建设成本相对较低,建设周期较短。然而,在注采压力和蠕变效应的双重作用下,地下煤柱及其围岩存在着移动变形的危险。本研究以选定的某煤矿采空区为背景,考察其性能和有效性,初步提出了将废弃房柱煤矿改造为天然气储气设施的简化技术途径。此外,本研究还对注采过程中的岩石运动、变形和裂缝特征进行了描述和解释。研究表明:(1)顶板初始挠度为142.91 mm,循环50次后挠度逐渐减小至226.06 mm;(2)注采过程结束后,矿柱上的应力和位移呈“拱形”分布。(3)当注采应力从1.8 MPa增加到8.2 MPa时,顶板与矿柱之间的垂直位移差从108.22 mm减小到91.28 mm。当注采压力接近现场条件时,存在失稳风险。(4)注采周期越长,上覆岩体裂缝的比例越高,裂缝的长度和孔径越大。研究成果从工程实践上为废弃煤矿改造储气设施提供了理论依据。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Geomechanics for Energy and the Environment
Geomechanics for Energy and the Environment Earth and Planetary Sciences-Geotechnical Engineering and Engineering Geology
CiteScore
5.90
自引率
11.80%
发文量
87
期刊介绍: The aim of the Journal is to publish research results of the highest quality and of lasting importance on the subject of geomechanics, with the focus on applications to geological energy production and storage, and the interaction of soils and rocks with the natural and engineered environment. Special attention is given to concepts and developments of new energy geotechnologies that comprise intrinsic mechanisms protecting the environment against a potential engineering induced damage, hence warranting sustainable usage of energy resources. The scope of the journal is broad, including fundamental concepts in geomechanics and mechanics of porous media, the experiments and analysis of novel phenomena and applications. Of special interest are issues resulting from coupling of particular physics, chemistry and biology of external forcings, as well as of pore fluid/gas and minerals to the solid mechanics of the medium skeleton and pore fluid mechanics. The multi-scale and inter-scale interactions between the phenomena and the behavior representations are also of particular interest. Contributions to general theoretical approach to these issues, but of potential reference to geomechanics in its context of energy and the environment are also most welcome.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:604180095
Book学术官方微信