Exploration study of synergistic mining between the fluidized leaching process enhancement of deep metal mines and geothermal energy development

The abundant metal minerals and geothermal resources reserved in the deep earth can provide key support for global economic development and human survival. As a subversive and unconventional mining method, the fluidized mining of deep metal ore provides an essential idea for the efficient, low-carbon, and safe development of deep resources. In view of this, we focus on metal mineral resources in the deep earth based on the uranium in-situ leaching technology; by combining the technical characteristics of the “metal mineral fluidization mining” and “deep geothermal development,” we innovatively propose the process concept of strengthening the fluidized leaching process of deep metal ore-geothermal co-mining, The idea structure and potential techniques to realize the process concept were discussed, and preliminary assumptions were given. This study mainly includes three steps: 1) investigation (such as investigating mineral properties and geothermal conditions), 2) preparation of systems (including drilling and pipeline transportation system, leaching solution and strain preparation system, geothermal utilization system, metal precipitation system, and production assistance system), 3) operation (including experimental results, optimize process parameter, and industrial utilization). Key systems, such as a dense solid mineral fluidization system, were proposed from the perspectives of mineral leaching, environmental perception, process control, energy replacement, and synergistic correlation. Key discussions were performed in five aspects: 1) the intelligent perception system for deep earth resources to solve the problems of low permeability, low penetration, premature solution preferential flow, low leaching rate, and excessive blockage, thereby decreasing the percentage of unsaturated leaching areas and effectively recycling the lower-grade minerals; 2) the seepage control system for solution in deep mining areas, divided into data acquisition, data analysis, and decision-making parts, thereby realizing efficient coordination between ground immersion environment and production information, avoiding system slowdown, and reducing heat/electric energy consumption; 3) the energy replacement system for geothermal–leaching solution, including the geological exploration and production monitoring system and ecological reclamation monitoring system, resulting in targeted adjusting the fluid flow behavior, improving capillary penetration and mass transfer; 4) the coupling system for thermal energy replacement–leaching solution circulation, which has three requirements—one is high temperature resistance, corrosion resistance and heat insulation, the second is good thermal conductivity and corrosion resistance, and the third is to be equipped with an intelligent monitoring system; 5) the thermal energy replacement-solution circulation coupling system that is based on large-scale pregnant solution container and equipped with thermal energy replacement, metal precipitation, leaching solution and strain preparation devices. Besides, the basic theoretical bottlenecks, key technical problems, and future development trends in the process of fluidized leaching–geothermal cooperative co-mining of metal ores are carefully discussed in this study. This study will provide ideas and references for enhancing the fluidized leaching process of deep earth metal ores and geothermal co-mining.