Theory of TSL tuyere operation and its practical validation

During accelerated melting in the Ausmelt furnace, engineers at JSC Karabashcopper encountered a situation where the tuyere tip, while immersed in the melt, rolled without any visible signs of burning. This phenomenon led to a disruption in melting conditions and a forced shutdown for tuyere replacement. The authors were not aware of any similar phenomena in the technical literature or available interna-tional practice on the operation of TSL tuyeres. Therefore, a theory of this process was developed, along with methods for controlling its manifestation and preventing its occurrence. With regard to the design of the tuyere under consideration, in order to simplify and speed up the ana-lysis of twist, it is proposed to use the derived relationships between effective twist and twist parameter. It has been shown and confirmed in practice by tests on an industrial furnace that in order to operate in the most efficient mode, it is necessary to maintain a cooling air to oxygen-air mixture flow rate ratio of 0.45–0.65. Within the framework of the proposed mass transfer mechanism, it was demonstrated that the riveting phenomenon occurs at specific twist parameters. Experimental studies confirmed the hypothesis that the effective twist parameters of all co-current jets of a TSL-type lance influence the furnace operation, refractory lining, tip, its wear or deformation pattern, and also the copper content of the matte and slag, all other things being equal.