Investigations of maximum use conditions of chemical reactions heat at sulphatizing roasting of rough copper sulphide concentrate

The paper describes the results of multifactorial experiments of roughing granulated copper sulphide concentrates on the influence of the sulfur content in the concentrate, specified air temperature, the granule size, the air flow on the study of conditions of the maximum use of the chemical reactions heat in the sulphatization roasting process. Mathematical models are received, which are used to determine the roasting optimal area from the point of view of getting into the zone under the terms of allowable temperature to avoid sintering material as well as the terms of preservation of the sulfates image. It is found that not exceeding admissible calcining temperature can be achieved even if the sulfur content is greater than 10 % due to the temperature decrease and the use of larger granules. But at an air temperature of 500 °C the optimum temperature is exceeded at any circumstances. The apparent activation energy calculated from the DTA data amounted to 27.714 kJ/mol and shows that the process is controlled by internal diffusion of gaseous reactants through the bed of formed sulfates.