A new method for exploiting mine geothermal energy by using functional cemented paste backfill material for phase change heat storage: design and experimental study

The research on mine geothermal energy exploitation has attracted global interest for many years. This paper proposes an innovative new method for geothermal-coal synergetic mining (GE-COSM) to expand the valorization of coal-based solid waste (C-BSW), reduce the environmental damage caused by coal...

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Detalles Bibliográficos
Autores: Liu, Hengfeng, Rodríguez Dono, Alfonso|||0000-0002-2296-4826, Zhang, Jixiong, Zhou, Nan, Wang, Yanjun, Sun, Qiang, Zhang, Luobin
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/372016
Acceso en línea:https://hdl.handle.net/2117/372016
https://dx.doi.org/10.1016/j.est.2022.105292
Access Level:acceso abierto
Palabra clave:Geothermal resources
Phase change material
Waste valorization
Geothermal-coal synergetic mining
Latent heat storage
Deep mines
Energia geotèrmica
Àrees temàtiques de la UPC::Energies::Energia geotèrmica
Descripción
Sumario:The research on mine geothermal energy exploitation has attracted global interest for many years. This paper proposes an innovative new method for geothermal-coal synergetic mining (GE-COSM) to expand the valorization of coal-based solid waste (C-BSW), reduce the environmental damage caused by coal utilization, and achieve a low-carbon transformation of the energy structure. A functional cemented paste backfill material (F-CBM) utilizing C-BSW for phase change heat storage was invented through orthogonal testing. This study obtained the main factors influencing raw material proportions on F-CBM working properties. Moreover, the optimal ratio of F-CBM raw materials was determined. F-CBM prepared with the optimal ratio showed improved working properties: the thermal conductivity (TC) and specific heat capacity (SHC) were increased by 75.70 % and 111.90 %, respectively, and the highest latent heat value was 17.37 J/g. The F-CBM's strength loss mechanism was discussed in terms of its mesostructure. In addition, it is shown that the backfilling layer formed by F-CBM in the goaf act as a thermal insulation and a phase change heat storage layer. Finally, the mine design principles of GE-COSM at different stages are summarized. These findings provide a reference for the application of F-CBM in engineering practice, and lay the groundwork for exploiting the mine geothermal energy.