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Exhaustion of deposits of ore and nonore minerals, the increase in costs for mineral raw materials, and increasing ecological problems have created an increasing interest in recent years in secondary resources, composite processing of raw material, and the development and introduction of low-waste and waste-free methods.The use of secondary resources makes it possible to solve problems of providing raw materials, to reduce costs for their extraction and processing, and to reduce industrial discharges into the atmosphere and hydrosphere. In addition, processing of spent materials accelerates recultivation of disturbed lands and return of them to agriculture. These are obvious advantages of use of secondary resources.For production of refractories there is interest in metallurgical industry wastes, particularly in slags formed in production of ferroalloys, which at present in many plants are shipped to the slag dump.We will present the results of a technical, economic, and ecological evaluation of methods of production of periclase-spinellide-forsterite refractories with use of magnesiasilicate slags of Serov Ferroalloy Plant, of production of high-alumina cement and dry concrete mixtues and compounds from Klyuchevsk Ferroalloy Plant, and of production of periclasechromite unfired ladle parts with use of steel plat refractory scrap.The slags formed in melting of high-carbon ferrochrome at Serov Ferroalloy Plant have a magnesia-silicate composition and include forsterite (65%), aluminomagnesia spinel (24%), glassy phase of melilite composition (5%), and ferrochrome (6%). The refractoriness of the slags is 1700~This indicates the desirability of their use as raw material for magnesia refractories [i].In Eastern Refractory Institute a method of production of periclase-spinellide-forsterite (PShF) parts, forsterite-spinellide (FSh) refractories, and unfired periclase-spinellide (PShBS) and forsterite-spinellide (FShBS) nozzles and inserts ((PShBV, FShBV) has been developed [2,3]. The experimental lots of PShF parts were produced at Panteleimonovka Refractory Plant.Tests of PShF parts in the lining of an anodic furnace of Kyshtym Electrolytic Copper Plant showed life of them equal to that of chromite-periclase parts. Forsterite-spinellide refractories (FSh) and steel pouring nozzles (FShBS) were prepared at Magnesite Compound using high-carbon ferrochrome slag with addition of sintered periclase powder to eliminate the negative influence of the glassy phase of the slag. Therefore the positive results of tests of forsterite-spinellide parts with use of Serov Ferroalloy Plant magnesia-silicate slags in different steel production equipment indicates that the refractories developed are at least as good as chromite-periclase parts and in a number of cases exceed them in life.All-Union Refractory Institute.

perature in the filling is above that os the original firing, the processes of silica transformation into the higher-temperature modifications continue, and at the moment of formation they have imperfect structures and are easily subjected to reduction and breakdown.The maximum weight losses and the most rapid growths are shown by specimens fired with short soaks (10-25 h). This is connected both with ~he significant embrittlement of the structure and with the maximum imperfection of crystallization and modification inversions (in the specimens 15-35% of residual quartz is preserved, the cristobalite is in the form mainly of metastable structureless silica). The resistance of the dinas specimens to reduction rises with prolongation of the soaking during firing (Fig. 8).It should be mentioned that firing in a medium of solid reducer causes a certain reduction in the strength of the specimens with a simultaneous reduction in porosity. In this case the porosity is reduced more during firing in coke than in the earbon,whichapparently is explained by the effect of fluxes from the coke ash.Reduction firing markedly alters the mineral composition of the specimens: there is a big reduction in the quartz content (especially in underfired specimens, i.e., first heat-treated at 1360 ~ and 1400~ with a soak of 10-25 h); there is an increase in the amount of cristobalite, reaching 30-40% (sometimes 50%), and the eristobalite consists of laminar fl-form; there is an increase in the tridymite content (except for specimens fired at 1440~and also in the silicates, glass, iron oxides and sulfides, especially after reducing firing in coke. The residual content of SiO 2 in specimens after reducing fire in coke does not exceed 92.6% (with an original content of 93.8-95.2%), indicating absorption of elements from the coke ash. CONCLUSIONSA reduction in the maximum grain size of dinas batches and an increase in pressing force ensure high apparent density in the articles, which increases their resistance to the action of solid reducing agents.The optimum firing temperature for dinas refractories should be considered as 1400~ an increase or reduction in this by 40~ causes a fall in the resistance of the dinas to reduction, which is connected with the incompletion of the processes of crystallization (at 1360~ and excess embrittlement of the structure (at 1440~ Prolonging isothermal soaking of specimens during their first firing contributes to more complete mineral formation, growth and ordering of the crystals of the high-temperature modifications, which increases the material's resistance to the action of the reducing agents. The service conditions of rammed linings in the gutters of blast furnaces require the use of materials resistant to corrosive iron and slag. Use is made of carbon, silicon carbide, and high-alumina compounds [1][2][3].To cheek whether we can use silicon carbide and electrocorundum in compounds for gutter linings, the Magnitogorsk combine (MMK) made laboratory investigations of their corrosion by iron and slag. The...

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