Recycling Dispersed Waste of Ferroalloy Production on the Basis of Metallurgical Self-Propagating High-Temperature Synthesis

Abstract

A review of techniques for recycling dispersed waste of ferroalloy production is conducted. The formation and accumulation of cyclone dust (catch product of crushing or CPC), formed during the grinding and fractionation of ferroalloys is considered. The drawbacks of the known techniques of handling this dust are shown. The possibility of obtaining commercial nitrided hardeners from CPCs and off-spec ferroalloy fines by self-propagating high-temperature synthesis (SPHTS) is studied. The proposed metallurgical SPHTS is used to develop the technology and show the possibility of bulk production of nitrided ferrosilicon, ferrovanadium, ferrochrome, and other composites in demand on the global market. The materials made by SPHTS have better quality than the nitrided ferroalloys made by the common furnace technique; in particular, the former contain less hydrogen, oxygen, and other impurities, and are denser, stronger, more porous, etc. The production of nitrided ferroalloys and composite hardeners by metallurgical SPHTS is developed using the production facilities of the Etalon scientific and technological production company, which includes the potential of annually processing up to 5000 t of cyclone dust of ferrosilicon and other alloys. The new approach to adopting SPHTS in practice is developed, and the possibility of utilizing synthesized products in metallurgy shown. The manufactured products are intended for use mainly as alloying additives in the smelting of transformed, rail, stainless, high-strength structural, and other steels and alloys. Another demanding consumer of composite SPHTS metal materials is the production of refractories. The modification of conventional refractories used in the smelting of cast iron, steel, and nonferrous metals with new composite SPHTS materials based on nitrides, borides, carbides, and other hard-to-melt compounds allows making refractories much more enduring and cut the expenses for them.