Injection Metallurgy for Continuous Copper Smelting and Converting Fundamental Aspects of Mitsubishi Process

摘要

The Mitsubishi Continuous Copper Smelting andConverting Process is the typical applications of injectionmetallurgy to nonferrous metallurgical operation, where the topblowing multiple lance system is employed for the continuousfeeding of the raw materials and reaction gases into the moltenbath. This results in an effective dispersion of the reactants into astrongly agitated bath. These are considered as the major advantageof the process with respect to the high production efficiency. Onthe other hand, however, the strong agitation may cause aconsiderable amount of refractory wear, and the melt splashgenerated by the lancing may also have negative effects on theproductivity, i.e. the increase in the refractory wear, the metal loss,the heat loss, and the accretion growth, etc. Therefore, theoptimization of the blowing condition as well as furnace design isvery important to achieve a stable and efficient operation, andfundamental understanding of the injection, agitation, andsplashing is badly needed.In this paper, fundamental aspects of the Mitsubishi Processregarding injection, especially splashing phenomena, are discussed.The splashing on a vertical plane caused by the top blowing gasinjection onto liquid surface was investigated through physicalmodel study. As a result of the study, the splashing rate on thefurnace wall was well correlated with the physical properites of thebath materials, gas velocity, cavity shape, lance/wall distance andceiling position. Obtained equations were compiled in a computerprogram and have been successfully applied to the evaluation ofthe furnace design.