The removal of slag from melt surface of hot metal and steel ladles is a necessary condition to provide a deep desulphurization and dephosphorization of hot metal and steel in the process of their processing. A review of methods of slag skimming presented, mainly based on slag mechanical shoveling and its removal out of ladles by vacuum sucking. It was shown, that manipulators design for the slag skimming working instrument moving depends on the production scale, mass of the processed heats, amount and properties of the slag to be removed, production process intensity and ecological requirements. Peculiarities of designs and technical parameters of machines for slag skimming presented, designed by Irkutsk plant of heavy machinery, Scientific and Production Enterprise n.a. M.I. Platov, VNIIMETMASH, Kuznetsk and Novolipetsk steel plants. Technological methods of control of slag composition and physical properties considered, first of all of viscosity and fluidity, which have significant effect on selection of a method of slag skimming. Advantages and drawbacks of actions, aimed at more complete slag removal from metal surface by a scraper noted including bath blowing off by an inert gas, liquid slag tapping into am intermediate settling tank following its removal into a slag bowl. In case of satisfactory fluidity it is possible to slag removal by vacuum sucking, which at the same time promoted the melt degassing. Work done in this area abroad noted. Methods of vacuum slag removal developed in the USA and Japan described.
Evaluating the hot metal dephosphorization efficiency of different synthetic slags using phosphorus partition ratio, phosphate capacity and computational thermodynamics
