摘要
基于空间守恒-采矿损伤不变量方程,类比分析煤矿全垮落法长壁开采采空区垮落带和裂隙带覆岩破坏模式,推导夹河煤矿采空区垮落带和裂隙带垂向碎胀与空隙分布线性和对数函数表达式,提出煤矿采空区“两带”垂向碎胀-空隙特征演化过程的多阶段概念模型。在获得采空区覆岩“两带”空隙特征参数的基础上,结合“两带”空间范围呈倒漏斗状梯形结构假设计算夹河煤矿废弃采空区等效空隙/储水体积。进一步以体积法为基础,对废弃夹河煤矿矿井水所形成的中低焓热储热流体开发潜能进行评估。研究结果表明:夹河煤矿单个典型工作面采空区空隙储水体积约(3.4~3.8)×10^(5)m^(3),顶板岩性影响“两带”碎胀与空隙垂向分布,进而影响“两带”空隙储水体积约10%;废弃煤矿井巷空间储水体积小于采空区空隙储水体积约2个数量级,废弃煤矿地热资源化利用应更多关注采空区储水/热潜能;综合考虑井、巷和采场结构差异性,估算废弃夹河煤矿矿井水热流体的总体积约2.2×10^(7)m^(3),静态热储潜能约127 GWh(~4.6×10^(5)GJ),导热和对流热补给效应明显,可为废弃煤矿遗留形成的地热资源勘查及后续开发利用提供参考。
One basic principle of the‘equilibrium mining theory is the space conservation-based mining damage invariant equation.This paper analogically analyzes the damage patterns between caving and fractured zones in a long-wall coal mining goaf.Specifically,the paper derives linear(caving zone)and logarithmic(fractured zone)functional expressions to capture the vertical expansion and void distribution characteristics of the above two-zones in abandoned Jiahe colliery.On this basis,a multi-stage conceptual model is then proposed to describe the evolution processes of the vertical expansion and void distribution characteristics of the two-zone.After the required void characteristic parameters of the two-zone are obtained,the paper roughly calculates the void/water-storage volume under the hypothesis of inverted trapezoidal shape of the two-zone structure.Accordingly,the potential of the mine water-based low enthalpy geothermal fluid formed in abandoned and thereafter flooded Jiahe coal mine is evaluated using the volume method.The results indicate that the estimated water storage capacity contained in a typical long-wall mining goaf in abandoned Jiahe mine is 3.4~3.8×10^(5)m^(3).The overlying rock lithology affects the bulking factor and void ratio vertical distribution in the caving and fractured two-zones,and thereby the water volume and geothermal potential of the order of 10%.Moreover,the void-water stored in mining gobs is about two orders of magnitude larger than that in the shafts and tunnels for abandoned coal mines,which need to have more attention in future study.Finally,the total estimated water storage capacity of the abandoned Jiahe colliery is about 2.2×10^(7)m^(3),corresponding to a static geothermal potential of approximately 127 GWh(~4.6×10^(5)GJ),which may provide guideline for further exploration and exploitation.
作者
褚召祥
CHU Zhaoxiang(School of Mechanics and Civil Engineering,China University of Mining and Technology,Xuzhou 221116,China;State Key Laboratory for Geo-Mechanics and Deep Underground Engineering,China University of Mining and Technology,Xuzhou 221116,China;SinoProbe Laboratory,Beijing 100094,China)
出处
《工程地质学报》
CSCD
北大核心
2023年第5期1696-1710,共15页
Journal of Engineering Geology
基金
自然资源部矿山生态效应与系统修复重点实验室开放基金(资助号:MEER-2023-09)
国家自然科学基金(资助号:42107156).
关键词
采矿工程
采空区
碎胀
空隙
体积法
热储评估
Mining engineering
Goaf
Bulking
Void
Volume method
Geothermal reservoir assessment
