Credit: Zhong et al.
Health and safety researchers at The University of Queensland have found that low-temperature rocks in an underground mine could be used to cool the deeper tunnels – potentially saving lives in the future.
In new scientific research published in the international journal Process Safety and Environmental Protection, lead author and Sustainable Minerals Institute visiting student Kaiqi Zhong explained that heat stress is a danger to underground mine workers – and although conventional ventilation might seem like a fix, increasing mine airflow using mechanical ventilation causes energy consumption to skyrocket.
Real-world impact
To address this, Zhong and her collaborators modelled a system that sends hot air through naturally cooler tunnels closer to the surface before recirculating it – and the results showed that the air from the active mine area was cooled within the heat exchange zone by 11 % initially and was then kept cooler for hours.
“Simply increasing airflow doesn’t fix heat hazards—and it can stir up more dust,” Zhong said, and added that this technology is suitable for underground mines that have disused roadways.
“It may be particularly advantageous for deep mines with high heat hazards and access to natural low-temperature sources,” she said.
Further research needed
Zhong’s SMI supervisor, Minerals Industry Safety and Health Centre Professor David Cliff, explained that some mining companies spend a vast amount on cooling mines, especially in already hot countries like Australia.
“Given the high capital costs involved in the current methods, it merits a lot of further investigation to see if the costs and practicalities work out,” he said.
Zijun Li, a paper co-author and Professor at Central South University in Changsha, China, said the team hopes to partner with mining companies to conduct pilot trials in real-world conditions.
“As deep mining becomes more common, this could help worker safety and reduce costs,” he said.
