Chromium iron is divided into high carbon chromium iron (including charging grade chromium iron), medium carbon chromium iron, low carbon chromium iron, and micro carbon chromium iron according to different carbon contents. The smelting process of ferrochromium with different carbon contents varies. Next, ferrochromium suppliers will explain to you:
1. Low carbon ferrochrome: There are two main smelting methods for low carbon ferrochrome: high carbon ferrochrome refining method and electro silicothermic method. The high carbon ferrochrome refining method is further divided into refining high carbon ferrochrome with chromium ore and refining high carbon ferrochrome with oxygen. When using high carbon chromium iron from chromium ore concentrate, the refining slag has a higher viscosity and melting point, and the smelting process temperature should be relatively high. The traditional production method is still the electro silicothermic method. The electro silicothermic method is to use silicon in the silicon chromium alloy to reduce the oxides of chromium and iron under the condition of producing alkaline slag in the electric furnace, in order to produce medium and low carbon ferrochromium.
2. Microcarbon chromium iron: Microcarbon chromium iron is mainly used in the production of stainless steel, acid resistant steel, and heat resistant steel. There are methods for smelting low-carbon ferrochromium, such as electro silicothermic method and thermal mixing method. Electric silicothermic method for smelting low-carbon ferrochromium is the process of adding chromium ore, silicon chromium alloy, and lime to an electric arc furnace. Electric silicothermic method for smelting low-carbon ferrochromium mainly relies on electric heating to melt the furnace charge, and the silicon in silicon chromium alloy reduces Cr2O3 in chromium ore. The hot mixing method for smelting low-carbon ferrochromium is the process of mixing pre melted chromite lime melt and silicon chromium alloy into a ladle outside the furnace to produce low-carbon ferrochromium.
3. High carbon ferrochromium: The smelting methods of high carbon ferrochromium include blast furnace method, electric furnace method, plasma furnace method, etc. Using a blast furnace can only produce special pig iron with a chromium content of about 30%. As of 2012, high carbon ferrochromium with high chromium content was mostly smelted in submerged arc furnaces using the flux method.
