V. N. Koptelov

The Heat Conductivity of Carbon-Containing Refractories

Results of an experimental study of the heat conductivity of carbon-containing refractories, commercially available from the Magnezit Kombinat JSC, a leading manufacturer in the field in Russia, are presented. Heat conductivity anisotropy has been revealed in most materials studied. The heat conductivity in the pressing force direction is shown to be smaller than in the perpendicular direction. For comparison, data on analogous carbon-free refractories are considered.

Structural Features of Heavy-Duty Periclase-Spinellide Refractories Prepared from Chrome Ores of Different Origins

Chrome ores are natural mineral formations of magmatic origin composed mainly of chrome spinellide and accessory minerals crystallized from basaltic and ultra-basic magmas. They are also called chromites or, after the name of the main component — native chrome spinellides.

A STUDY OF MAGNESITES OF PROVENANCE FROM THE GOLUBOE DEPOSIT (KRASNOYARSKII KRAI) AND THEIR LABORATORY TESTS FOR TECHNOLOGICAL APPLICATIONS AT THE KOMBINAT MAGNEZIT JOINT-STOCK CO.

Results of a preliminary study of the composition and properties of magnesites of provenance from the Goluboe deposit (Krasnoyarskii Krai, Russia) are reported. All magnesites, irrespective of their varietal, structural, and textural features, can be considered as acceptable raw materials. The concentration of impurities and inclusions in a high-quality magnesite does not exceed 1.5%, whereas in low-quality magnesites (2nd grade) they are within 3 – 8% of the total mineral composition. The heat-assisted beneficiation or calcination of raw magnesite yields a material with 98% MgO and a CaO-to-SiO2 ratio greater than 3, which provides means for producing high-quality periclase powders. Tests conducted under industrial conditions show that using technologies of fine grinding, pelletizing, and calcination at 2100°C makes it possible to prepare dense periclase clinker. Calcination of lumpy magnesite at still higher temperatures is not an efficient technique for dense periclase powders. Clinker technology is shown to be the best way towards obtaining periclase and periclase-containing powders using raw magnesite from the Goluboe deposit.

Refractories for the Taphole of Converters

A range of refractory materials for the converters taphole lining commercially available from the Kombinat Magnezit Joint-Stock Co. and major aspects of the processing technology are considered. The effective use of antioxidant additions is confirmed by thermal analysis. Results of operational tests of refractory materials are discussed. The advantages of an innovative design of the taphole unit composed of blocks of variable diameter and assembled on a metal template are emphasized. An economic feasibility analysis of the use of periclase-carbon taphole blocks is given. The newly designed refractory material are shown to conform with the requirements of modern converter technology.

Electroseparation of sintered periclase powders

A laboratory separator and an industrial prototype developed by the Magnezit Integrated Works in cooperation with the Kola Branch of the Mekhanobr Institute for electroseparation of magnesite ores with an elevated content of dolomite and dolomitized magnesite are described.

Resource-saving technology for producing periclase powders with 92-95% MgO

A brief characterization of magnesite of the Satkinskoe Deposit and a technology for the production of periclase powders using two-stage firing of the raw material are presented. The quality of the fired product and the technical and economic parameters of the production of powders for basic refractories are described. Results on extraction of MgO into the fired products and an elemental analysis of caustic magnesite are presented. A possibility of two-stage firing in industrial conditions of reduced waste gases and quote of raw material consumption in the production process.

Properties for obtaining magnesia products from the Zabakal'sk group of magnesites

ConclusionsAn all-round investigation of the properties of refractories made from Zabaikalsk magnesites showed that they can be widely used in very diverse areas of metallurgy, engineering, medicine, perfume production, and other industries.

Investigation of refractories based on hollow periclase-containing granules

ConclusionsThe investigation into the possibility of obtaining periclase-spinel refractories of the PShPKh type based on fused materials and hollow KhGSh granules obtained on the “Plazmatron” equipment, showed unsatisfactory sintering of the granules with finely milled bond and, as a result, poor factors for compressed strength and refractoriness- under-load.In order to improve the production technology for refractories based on hollow KhGSh it would be of interest to activate the surface of the granules with various mineralizers and to choose finely milled bond.