Manganese Ferroalloys Research Articles

Titanium-bearing nonmetallic inclusions in manganese ferroalloys

Petrographic data indicate the chemical and mineralogical composition, topography, and morphology of various titanium-bearing nonmetallic inclusions of the type TiS, MnS-TiS, TiS-α-SiC, and TiS-MnS-TiC, as well as nonstoichiometric titanium sulfides and titanium carbonitrides.

Carbon reductants for the production of manganese ferroalloys

Carbon reductants for the production of manganese ferroalloys

Determination of the energy parameters for the smelting of manganese ferroalloys with increases in the electrode gap and electrode spacing

An increase in the power of ferroalloy furnaces also increases the current in the electrodes and, to a lesser extent, increases furnace voltage as well. There is a deterioration in the power factor and electrical efficiency in this case, the reason being a decrease in the resistance of the bath. Studies have shown that the power of furnaces used to make manganese ferroalloys can be increased by increasing bath resistance and voltage if the spacing of the electrodes and the distance between them and the bath are also both increased. These changes will improve the energy parameters of the smelting operation.

Computer simulation of equilibrium relations in managanese ferroalloy production

The complex heterogeneous equilibria associated with the production of manganese ferroalloys have been simulated using recently developed thermochemical databases. Over 600 measured equilibrium data have been used to verify and calibrate the model calculations. Good agreement is obtained for many important technical relations such as carbon solubility, equilibrium diagrams and phase relations, and element distribution as a function of temperature and composition. Experimental slag/metal and slag/metal/gas equilibria in MnO-SiO2 binary, MnO-SiO2-CaO and MnO-SiO2-Al2O3 ternary, MnO-SiO2-CaO-Al2O3 quaternary, and MnO-SiO2-CaO-Al2O3-MgO quinary systems can be reproduced within experimental uncertainties. The influence of temperature, CO partial pressure, and slag chemistry on the Mn- and Si-distribution equilibria has been quantitatively evaluated. This leads to a sound basis for optimizing the manganese ferroalloy production processes.

Silicomanganese production from manganese rich slag

Manganese rich slag produced by the appropriate treatment of high manganese pig iron has a high manganese content and results in low fines, is low cost and gives low excess oxygen. Manganese recovery from this slag in the form of manganese ferroalloys compensates for the excess cost of the treatment process. Manganese rich slags produced from the injection of high manganese pig iron under at optimum conditions have levels of (Mn)>35 wt-%, (Mn)/(Fe)>7.65, (Mn)/(Si)>2 and (Mn)/(P)>285, which satisfy requirements for use as raw material in silicomanganese alloy production. Various experiments were carried out to smelt high manganese slag resulting from the treatment of high manganese pig iron to produce silicomanganese in a bench scale submerged electric arc furnace. Use of such manganese rich slag in the proportion of 40% of the blend has been found to be optimum to obtain a silicomanganese alloy with the highest metallic yield and highest manganese recovery. The silicomanganese alloy produced satisfies the standard chemical specifications, with manganese and silicon contents 68 and 18%, respectively.

Use of slags from the production of manganese alloys in steelmaking

roalloys. One promising direction is the use of manganese slags in steelmaking, particularly in the oxygen-converter conversion of low-manganese pig irons. The addition of such slags in the necessary amounts simultaneously solves the problems of increas- ing the efficiency of oxygen-converter steelmaking and saving manganese ferroalloys. Studies were performed on the use of ladle residues (crests) of slag from the production of silicomanganese at the Nikopol' Ferroalloys Plant to make steels at the Nizhniy Tagil combine, Cherepovets Metallurgical Combine ("Severstal'"), and West Siberian Metallurgical Combine in 160-, 350-, and 300-ton converters from a semifinished product and pig iron with man- ganese contents of 0.02-0.05, 0.15-0.35, and 0.4-0.7%. The blowing rates were 1.9-2.4, 1.4-2.0, and 2.8-4.0 m3/ton.min, respectively. Ladle residues of slag from the production of silicomanganese consist of the alloy silicomanganese (15-25%) and the ferroalloy slag itself (75-85%). The ferroalloy slag contains 16--20% MnO, 8-10% A1203, 4--6% R20 , 3.5-4.5 MgO, 40-50% SiO 2, 10-15% CaO, and 0.7-1.2% S, and it has a melting point of 1250~ The ladle residues contain at least 30% MnOto t.

Reaction equilibria in the production of manganese ferroalloys

A laboratory investigation has been carried out to determine slag/metal and slag/metal/gas equilibria relevant to production of manganese ferroalloys. The metal phase was normally composed of MnSi-Csat alloys, but in some experiments, the alloys contained up to 15 wt pct Fe. Different slag systems were used: MnO-SiO2, MnO-SiO2-CaO, MnO-SiO2-Al2O3, and quaternary MnO-SiO2-CaO-Al2O3 with fixed CaO/Al2O3 weight ratios of 1.5 and 3. The experiments were normally made in CO gas atmosphere at temperatures ranging from 1450 °C to 1600 °C. The results give comprehensive information about equilibrium relations.Partial andcomplete equilibria are illustrated in equilibrium diagrams. Partial equilibrium is a situation in which equilibrium is established with respect to certain variables but not to others, in this case, between slag and metal but not with the gas phase. The effect of temperature was found to be of minor importance for the partial slag/metal equilibrium, whereas the complete slag/metal/gas equilibrium is considerably influenced by both temperature and CO pressure. As expected, increasing temperature and decreasing CO pressure will reduce the equilibrium MnO content of slags. The influence of alumina addition to the slag phase and of iron to the metal phase is also discussed.

A decision support system for the integrated production of manganese ferro alloys : G.R. Mateus, A.M.M. Almeida, pp 219–227

A decision support system for the integrated production of manganese ferro alloys : G.R. Mateus, A.M.M. Almeida, pp 219–227

The Manganese Shortfall in Russia

The status of Russia's access to manganese—a vital ferroalloy raw material—upon the disintegration of the USSR is examined. Russian manganese reserves are assessed from the perspective of ore quality and quantity in light of the disruption of once-steady supply relationships, current demand for manganese ferroalloys in the Russian steel industry, the capacity (or lack of same) of Russian ferroalloy plants to produce various manganese ferroalloys, the impact of modernization in Russian ferrous metallurgy on manganese consumption, and other factors that could affect Russian manganese demand in the future. 10 references.

A Decision Support System for the Integrated Production of Manganese Ferro Alloys

Abstract The manganese ferro alloys are basic raw materials for steelmaking. A nonlinear model for the production of manganese sinter, high-carbon ferromanganese and silicomanganese is proposed. The model is solved by three different approaches: nonlinear methods, constraint linearization and a heuristic composed of three linear subproblems. Their Computational implelnentation, the results obtained and their influence on management and process control are discussed. Based on the results we present a simplified design for a decision support system.

Thermodynamics of Reducing Dephosphorization of Manganese and Manganese Ferroalloys.

Thermodynamic conditions of dephosphorization of manganese and its ferroalloys with calcium containing fluxes have been analyzed with the help of experimental data on the thermodynamic properties of Mn-P and Ca-P alloys obtained earlier. Equilibrium coefficients of phosphorus distribution between liquid manganese and slag have been calculated. An influence of oxygen and nitrogen partial pressures in the reaction zone on dephosphorization has been established.