Issues of resource and energy saving in corundum production
The purpose of this article is study and identification of the most promising trends and engineering solutions in order to improve resource saving and energy efficiency in the production of corundum on the basis of the conducted patent review on melting improvement and optimization. The ways to optimize the corundum production are considered in three directions from the point of view of energy saving. The first direction relates to the development of promising engineering developments. The latter are studied to select rational operating modes and determine the main factors affecting voltage surges during the technological process and useful product yield. Consideration is given to the conditions for reducing specific energy consumption and improvement of production environmental friendliness at all stages beginning from isothermal sintering of corundum, production of electrocorundum, fine corundum to single corundum crystals. The second direction is the optimization of corundum production at all stages for the development of an optimal control algorithm for the technological process. In this case the electricity consumption might be reduced by 10-12% as compared to current standards. The third direction is the development of engineering solutions involving the change of individual structural units of furnaces, namely, the use of modern components and new heat insulating materials, as well as the application of spent heat carriers as the sources of secondary energy resources and the introduction of additional controllers of the automated control system of the process. The analytical study has shown that the result of optimization should be upgraded designs of plants and electrical equipment, which can provide maximum electrochemical efficiency, and corresponding furnace tightness. Criteria for energy supply and energy quality making possible to stabilize furnace material balance and solve resource saving issues have been developed. These measures allow to reduce the loss of raw materials up to 20-25%, the specific energy consumption under the production of corundum by 2-3 thousand kWh per 1 t.