| The copper flash smelting process is a complicated process coupled with multi-operational variables and reactions. For more than fifty years being applied in industry, the flash smelting technology has attracted great attentions of copper-smelting professionals worldwide with its technical advantages and better economic benefits, and further opened a new era of higher technological level in copper industry since the working regime of 'Four Highs' has been put in practice. Along with enhanced smelting intensity and smelting norms, higher demands are set on the productive system of flash smelting furnace (FSF). Hence it seems to be more important to follow the technical sequence of'mathematical modeling-hologram simulation-comprehensive optimization' and to carry out computational simulation and optimization researches on rational enhancement of the copper-smelting process and protection of the FSF furnace's linings, aiming to further intensify smelting processes and reduce energy consumptions.In order to meet the demands for enhanced production, to coordinate better systematic arrangement and to scientifically tap the latent power of system production, in this paper, based on detailed study of the smelting processes, equipments and models for balance computation of material and heat in flash smelting process, a mathematical model for simulation and optimizations of flash smelting system has been developed by considering four links and six factors in the system. Moreover, simulative enhancement experiments for Guixi Smelter's FSF have been carried out, possibilities for the system to be enlarged and re-built been expounded, and optical parameters such as matte grade, oxygen-enriched smelting, slag compositions and copper concentrate been proposed.Intensified smelting process not only sets higher demands on the system equipments but also makes the work environment of furnace linings even worse and more prone to be damaged. Based on the study of erosion mechanism of linings in a reaction shaft of FSF, the author found that, under the cover of frozen slag, the refractory bricks of shaft were mainly damaged at high temperature by the erosion of smelted matte, slag and erosive gas. So, if effective measures are to be adopted to control the linings' surface temperature within a reasonable range, the inner walls of the shaft will be protected better and the furnace life will be prolonged longer.In numerical simulation of the frozen profile of reaction shaft in a copper flash smelting furnace, the author established a numerical model for the temperature field of shaft's linings. Giving the shaft's frozen profile definition and physical boundaries and analyzing the forming process and variation mechanism of wall slag and moving boundaries in reaction shaft, the author proposed and defined the conception of 'over-cooled state' and 'over-heated state', studied in detail the physical model and its mathematical solution during the research of the frozen profile of reaction shaft, and developed an on-line monitoring system for the frozen profile of shaft's inner surface. The system2002later has been applied in two flash furnaces located in Guixi Smelter and Jinlong Copper Company, Ltd respectively. Since provided with real time simulative monitoring and warning analysis of wall situations of the reaction shaft in a smelting process, technicians then are greatly helped in better adjusting operation parameters in-site, controlling the wall temperature and protecting the furnace.Finally in this paper, the author carried out both the numerical simulation and optimization researches on wall structures of reaction shaft in Guixi's flash furnace. By establishing a three-dimensional analytical model for heat transfers in local wall of the shaft, the author proposed optimized structures of reaction shaft, such as improving the heat conductivity of the wall refractory, decreasing the wall temperature and reducing the thickness of bricks, to help the furnace to work better and longer.
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