基于相变-蓄热充填体的矿床-地热协同开采基础理论研究

High ground temperature conditions in deep mines have great potential for geothermal exploration. This project proposes to use the phase change filling body as a heat storage carrier, and to use the partition wall heat transfer technology, combined with the pump or gravity to drive the circulating heat carrier medium, then realize the academic concept of “Deposit-Geothermal Cooperative Exploitation”. The following studies are planned to be carried out: a) Based on the comprehensive consideration of thermal properties and work performance, a model based on multi-objective decision-making theory is established to optimize its mix ratio parameters of phase change-heat recovering backfill materials; b) The phase transition-retention heat transfer characteristics of the regenerative backfill and the mechanism of storage/release of heat are investigated, as well the phase transition behavior and heat transfer coupling law of the phase change material in the phase change-regenerative backfill is studied, then a numerical heat transfer model is established; c) The thermo-mechanical behavior of the phase transition-regenerative backfill under multi-phase/multi-field coupling conditions is revealed, and the thermo-mechanical coupled constitutive model of different multi-scale hierarchical phase transition-regenerative backfill is established; d) Considering the requirements of process, time, space, and environment coordination, a deposit-geothermal cooperative exploitation model based on phase change-heat recovering backfill is put forward and a new mines' renewable energy production methods is explored. With smooth development of this project, the organic combination of mining, geothermal development and filling mining technology can been realized, which has important theoretical significance and engineering application value.

深部矿井的高地温条件使其在地热开采方面具有巨大潜力。本申请项目提出以相变充填体为蓄热载体，采用间壁式换热技术，结合泵体或重力驱动循环载热媒介，实现“矿床-地热协同开采”的学术理念。拟开展以下研究：①在综合考虑热物性及工作性能的基础上，建立基于多目标决策理论建立相变-蓄热充填材料配比参数优选模型；②探索相变-蓄热充填体相变传热特性与蓄/释热机理，获知相变-蓄热充填体中相变材料相变行为与传热的耦合规律，构建其数值传热模型；③揭示多相/多场耦合条件下相变-蓄热充填体热-力学行为，建立不同多尺度层次相变-蓄热充填体的热-力耦合本构模型；④基于相变-蓄热充填的矿床-地热协同开采模式，在满足工艺、时间、空间、环境协同的要求下，探索新型矿山可再生能源生产方式。本项目的顺利开展，实现了矿床开采、地热开发和充填采矿技术的有机结合，具有重要的理论意义和工程应用价值。

针对深部矿床开采面临的高地应力、高地温问题，创新性地提出了“矿床-地热协同开采”的学术理念。通过对充填材料的热学、力学性能的测试与分析，基于多目标决策理论得到充填材料配比参数的优选方法；构建充填体蓄热/释热本构模型，通过数值模拟获知了充填体的相变蓄热/释热机理、蓄热/释热过程中充填体内部温度场的时变特性、换热管之间的热干扰以及不同采热状况下充填体的蓄热/释热性能与采热效率；充分考虑深部采场条件下充填体蓄热/释热过程中温度场-应力场的循环变化，建立充填体热-力耦合模型，探知了充填体的温度场、应力-应变场及应力场-温度场等的热-力耦合过程；构建了矿床-地热协同开采的总体方案和协同体系，提出矿床与地热开采、采场降温与地热开采以及充填体养护与地热开采3种基本协同模式，形成一套完整的针对充填矿井的矿床-地热协同开采基础理论体系，实现了矿床开采、地热开发和充填采矿技术的有机结合，具有重要的理论意义和工程应用价值。