V. P. Vorob’ev

Production of Manganese Alloys from Rich High-Basicity Ore

Most manganese ores exported by world producers are characterized by low basicity (<0.5) and may accordingly be used in single-stage smelting of ferrosilicomanganese by the slag method. We know that many deposits have large reserves of highly basic manganese ore [1, 2]. The chemical composition of such ore is outlined in Table 1. The ore basicity is in the range 0.76‐2.93, which is 1.5‐6.0 times the permissible level for ferrosilicomanganese production by the slag method. Only high-carbon ferromanganese may be produced from such ore. The smelting of carbon ferromanganese by the flux method on the basis of low-basicity (acidic) ore has been adequately covered in the literature and introduced in practice [3‐5].

Physicochemical classification of carbon-based reducing agents in electrometallurgy

The reducing agents employed in ferroalloy production are classified for the first time on the basis of their primary physicochemical properties in slag-free (FeSi, FeSiCr, FeSiMn) and slag-based (FeCr, FeMn) processes. The goal of the classification is to improve the production process.

Lignite-coke briquets in ferroalloy production

Kansko-Achinsk 2B and 3B coal is of interest not only as a fuel but also as a raw material for the production of metallurgical reducing agents. Theoretical and practical aspects of the manufacture of briquets based on medium-temperature coke (thermocoke) produced from Berezovsk 2B lignite and their use in ferroalloy smelting are considered. The new material is compared with metallurgical coke. Keywords: coke, coal, medium-temperature coke, reduction, silicon, chromium, shaft electrofurnaces, gas liberation, ferroalloys

Prospects for imported high-basicity manganese ore in Russia

Abstract-Given the lack of suitable manganese-ore reserves in Russia, more than 75% of the manganese alloys employed are imported. In order to produce a wide range of manganese products using the available Russian electrofurnaces, new methods based on imported low-phosphorus high-basicity ore are promising.

Carborundum-bearing carbon reducing agents in silicon and silicon-ferroalloy production

As theoretically predicted, the manufacture of silicon and its ferroalloys is improved if carborundum abrasive produced in Acheson furnaces is introduced in the batch. Approaches to the production of carborundum-bearing carbon reducing agents in ferroalloy electrofurnaces are considered. Two-stage technology is shown to be more effective than the existing technology.

Carborundum-bearing reducing agents in high-silicon alloy production

The creation of a new class of carbon reducing agents containing 40–95% carborundum is considered. The carbon is derived from a wide range of natural and industrial materials, including mill siftings, coke, semicoke, high-ash coal, and coal-enrichment wastes. By two-stage production—first of carborundum-bearing reducing agents and then of high-silicon alloys—the range of possible raw materials may be markedly expanded, and the costs of materials and energy in alloy production may be significantly reduced.

Classification of quartzites by gasification from a mixture with carbon reducing agents

Considerable time is required for industrial tests to assess the utility of quartz and quartzites in the production of silicon ferroalloys. A relatively simple method of classifying quartzite with respect to the production of silicon, ferroalloys, carborundum, and carborundum-bearing reducing agents has been devised on theoretical principles and introduced in practice. This method is based on measuring the degree of gasification of quartzites from a mixture with carbon reducing agents whose composition is calculated so as to ensure stoichiometry of the reaction SiO2s + Cs = SiOv↑ + COg↑.

Electric arc in three-phase metallurgical furnaces

The theoretical and practical assumptions relative to the studies of electric arcs in steel-melting furnaces presented in journal Electrometallurgiya in 2011–2012 are subjected to a critical analysis. Based on classical concepts and the author experiments, the concept is presented regarding to the phases of the state and parameters of arc discharge in the ac electromagnetic field of a three-phase system. Industrial methods of eliminating the injurious effect of flash arc on furnace lining and the furnace efficiency are considered.

Parameters of the lower-belt lining of ore-smelting electric furnace shafts for melting high-silicon ferroalloys

The graphite belt (GB) of the bottom is an important element in the design of the shafts of oresmelting electric furnaces, since it prevents an oxide lining from contact with liquid ferrosilicium. The problem of choosing the GB height as a function of the furnace power and the silicon content in an alloy is formulated and solved.

Methods for the efficient use of the gas energy from shaft ferroalloy electric furnaces

The average values of these efficiencies are as follows: η t = 0.5‐0.7 and η e = 0.90‐0.95. At η f = 0.45‐ 0.66, the energy lost by radiation from the furnace top, furnace jacket, and electrode surfaces; by cooling water and air; and, most importantly, by the physical heat of the waste gases is at least 30‐50%. The chemical energy of the waste furnace gases (ferrogases) is a substantial source for the compensation of the heat losses in ferroalloy furnaces and, hence, for electric energy saving. It was theoretically found and experimentally supported that the gas products of the reduction reactions occurring in the working space of shaft furnaces contain a significant amount of the gas components (CO, H 2 , CH 4 ) that have a high calorific value (CV) [1]. The problem of the efficient utilization of the ferrogas energy has not been adequately elucidated in available works. There are different data on the use of a ferrogas in a mixture with natural gas in furnaces for burning limestone. Powerful (more than 60 MW) foreign-made furnaces for making ferromanganese and ferrochromium have a system for reburning a ferrogas in the mounted bins where the initial charge is heated [2]. We estimated the chemical energy of the gases accompanying the slag-free and slag processes in 16.5‐ 75 MV A furnaces (table). The calorific value (kcal/m 3 ) was calculated by the formula ηf ηtηe,