Remarks on Heat Emission during Operation in Hot Rock Mass and on Possibilities of Its Use

Abstract

Heat flow in a hot mining department, where the original temperature of rock is greater than 50 0 C has been studied. The total power of electrical equipment installed in the department amounts to about 6 MW. In accordance with the current climate regulations of Polish mining, the air temperature in the workplace, measured with a dry-bulb thermometer may not be higher than 33 0 C. In order to be able to ensure a temperature consistent with the regulations in such department, fresh air supply workings must be equipped with chillers of a total refrigeration capacity of 2 MW. The carried out analysis of the results of climate forecasts and of the results of the rock mass cooling modelling around these workings has shown that approximately 30% of the cooling power is needed to receive the heat from the hot rock massif. Assuming the required air temperature at 28 0 C (enabling an unshortened working time), then the cooling power needed to extract heat from the rock mass would be much greater. The studies carried out show that the amount of heat emitted in the department also depends on the phase of the longwall course (the length of main gates and changes in rock temperature in them). It has been proposed that hot water from condensers supplies the crystallizers of surface (absorption) cooling devices. In this way, reduction of the air-conditioning expenditure will be obtained.