Deep mine underground thermal environment regulation and energy-saving technology based on controlled recirculating ventilation

Mine ventilation regulates underground thermal environments, but deep mines encounter ventilation inefficiency and elevated cooling energy demands. This study introduces controlled recirculating ventilation (CRV) as a solution for deep mine thermal management. The CRV technology diverts hot return air to shallow roadways for rock-mediated cooling, subsequently mixing the cooled air with fresh air for deep roadway supply. A COMSOL multi-physics model was developed to evaluate the CRV performance under varying operational parameters. The CRV achieves a temperature reduction of 1.02 °C compared to conventional ventilation systems by day 25. The sensitivity analysis of influencing factors was performed demonstrate that burial depth of recirculation pathways demonstrates a strong negative correlation with cooling capacity, while vertical elevation differences between cooling and deep zones reduce cold energy transport efficiency. Additionally, recirculation ratio exhibits a positive correlation with thermal performance. Moreover, pre-ventilation of shallow roadways reduces deep roadway inlet temperatures by 2.51 °C relative to non-pre-ventilated conditions. Principal component analysis identifies burial depth as the dominant controlling factor. With a provided cooling capacity of 16.096 kW, CRV presents itself as a technically viable and cost-effective auxiliary cooling methodology for deep mining environments. © 2025 Elsevier Ltd.