A Numerical Investigation on Utilizing Jacket Water Waste Heat of Power Generation Units in Remote Mines

Reliance on fossil fuel to generate power and to precondition the intake air for secure underground operation increases the carbon footprint of the remote mines in cold climatic zones, such as Canada and Sweden. Although the fossil fuel-based power plants are the most dependable options in these off-grid establishments, almost two-thirds of the burnt fuel to generate electric power is discarded as heat through the various streams. Identifying this scenario, the present study conducts a numerical analysis on preheating the mine intake air with the heat wasted through the jacket water of these power generation units. A MATLAB-based thermodynamically coupled code was developed to assess the techno-economic viability of the proposed concept. Parametric studies on the effectiveness of heat exchanging units showed that investing in the improvement of the heat delivery devices would be more important than the heat recovery units. Sensitivity analysis conducted on the diesel power generation, intake airflow rate of the mine, and modified heating degree days of the remote location established the necessary degree of confidence in the results obtained from the investigation. Analysis indicated that a typical off-grid mine in northern Canada could save around two-thirds of the fossil fuel burning for heating purposes and reduce the associated carbon emissions.