Ferbasa

As an alloying compound, high carbon ferrochrome, or charge chrome, is used to manufacture stainless steel and special alloys. Stainless steels are used in a variety of industries, including food, petrochemicals, chemicals, pulp, construction, white goods, dental and medical equipment, and domestic utensils, among others.

Raw Materials: Chrome Ore, which is made up of the useful compounds Cr2O3 and FeO, with gangue that is made up of SiO2, Al2O3, MgO, CaO and P. The reducer, elemental carbon, mainly comes from metallurgical coke and/or charcoal.

Reduction Reactions: The raw materials are loaded into a submerged-arc reducing furnace, and using an electro-fusion process, the ore Cr2O3, FeO and part of the SiO2 react with the carbon in the reducers, obtaining the alloy, containing Cr, Fe, Si, C and P, which is called High Carbon Ferrochromium (HCFeCr). The main reactions are described in the processes indicated below:

Cr2O3 + 3C ------> 2 Cr + 3 CO
FeO + C --------> Fe + CO
SiO2 + C --------> Si + CO2

The HCFeCr alloy and the slag are produced simultaneously in the furnaces. The furnaces are emptied periodically and the alloy is molded in a specific area, where it is cooled, comminuted (crushed) and classified based on customer specifications. Click here to see the flowchart.

Typical Alloy Composition: The typical composition of the High Carbon Ferrochrome (HCFeCr) alloy is represented below:

Cr 55%
C 7.8%
Si 3.5%
P 0.025%
S 0.020%

Low Carbon Ferrochrome is used in steel production to correct chromium contents levels without causing undesirable changes in the carbon content. The basic feature of these alloys is a low carbon content of, at most, 0.15%.

Raw Materials: Chrome Ore, in the wet concentrate form (< 2 mm), which must be dry (max 1% humidity) to be used; Quicklime, used as a flux for chrome ore, whose high CaO content is desirable for ensuring an easy dissolution and low energy consumption, with a grain size of 20 to 30mm; Ferrochrome Silicon, with a grain size from 15 to 20 mm, which is added after the smelting of the quicklime and chromite and acts as a reducing agent in the manufacture of LCFeCr.

Fusion of Raw Materials: The fusion of the quicklime and chromite mixture takes place in an open-arc electric furnace. After the furnace is duly loaded, the goal is to obtain a certain amount of molten mass per run, as shown in the flowchart below.

Reaction - Addition of FeSiCr: When the mixture becomes a molten mass and both temperature and fluidity are adequate, it is poured into a ladle coated with chrome and magnesium. Subsequently, a mobile arm adds FeSiCr. Elemental silicon (Si) is the reducing agent for the chrome ore oxides through the following reactions:

2 Cr2O3 + Si ------> 4 Cr + 3 SiO2
2 FeO + Si ------> 2 Fe + SiO2

Most of the silica separates out as slag, while the Cr and Fe react to form LCFeCr. Click here to see the flowchart.

Typical Alloy Composition: The typical composition of the Low Carbon Ferrochrome (LCFeCr) alloy is represented below:

Cr 61%
C 0.15
Si 1.0
P 0.035
S 0.015

Ferrochrome Silicon is used as a reducing agent in the manufacture of low carbon ferrochrome and in steels, for the addition of chromium and silicon.

Raw Materials: High Carbon Ferrochrome, which is produced by FERBASA as described in the item "Production of HCFeCr alloys (HIGH-CARBON FERROCHROME), whose function is to supply the elements Cr and Fe; the reducing agent, elemental carbon, which is mainly obtained from charcoal; Quartz, which contains the useful compound SiO2; and gangue composed of Al2O3, TiO2, MgO, CaO and P.

Reduction Reactions: During the production process, when all raw materials are fed into the submerged-arc reduction furnace, the carbon reacts with the oxygen in the quartz’s SiO2, obtaining Si. The only requirement for the production process is the reaction shown below, regardless of the source of the oxides or the carbon.

SiO2 + C --------> Si + CO2
HCFeCr, supplying Cr and Fe, fuses in the furnace with the Si from the reaction to form the FeSiCr alloy. Click here to see the flowchart.

Typical Alloy Composition: The typical composition of the Ferrochrome Silicon (FeSiCr) alloy is represented below:

Cr 30 to 35 %
C 0.10
Si 40 to 50 %
P 0.035
S 0.025

Standard FeSi 75 is used in steel production as a deoxidizer and alloying element; in the foundry industry it serves as a graphitizing agent. HPFeSi (high purity) is used in the production of steel for the manufacture of transformers, hydroelectric dams, freezers, hermetic compressors for refrigerators and refrigeration systems and hybrid motors for automobiles, among others.

Raw Materials: Hematite, whose useful compound is Fe2O3 and gangue composed of SiO2, Al2O3, MgO, CaO and P; the reducing agent, elemental carbon, which mainly comes from metallurgical coke and/or charcoal; quartz<0} which is made up of the useful compound SiO2; and gangue composed of Al2O3, TiO2, MgO, CaO and P.

Reduction Reactions: During the production process, the reducer enters into contact with the quartz and the hematite, reacting with the oxygen in the compounds SiO2 and Fe2O3, obtaining alloy containing Fe, Si, C and P. The only requirement for the production process are the reactions shown below, regardless of the source of the oxides or the carbon.

SiO2 + C --------> Si + CO2
2 Fe2O3 + 3 C --------> 4 Fe + 3 CO2

Click here to see the flow chart.

Typical Alloy Composition: The typical composition of the Ferrosilicon 75 (FeSi 75) alloy is represented below:

Si 75.0%
C 0.10
P 0.05
S 0.020
Al 0.60

Basic raw material used in the production of metallurgy and foundry fluxes, such as molding sand.

Basic raw material used in the manufacture of high carbon ferrochrome.

Basic raw material used in the manufacture of high carbon ferrochrome.

Low phosphorous quicklime is used as a flux in the production of low carbon ferrochrome and the production of steel.

Material derived from the production of silicon metal and ferrosilicon alloys in electric furnaces, microsilica ensures greater durability, impermeability and resistance to high performance concrete and mortars.