production methods of ferroalloy
The ferroalloy production is a process in which furnace charge, reducing agent, slag material, and composition regulator undergo physical and chemical changes at high temperatures to generate alloy, slag, and furnace gas. There are many varieties of ferroalloy, the raw materials are complex, and the physical and chemical properties of the extracted alloying elements vary greatly, so the production methods used are different.
The production methods of ferroalloy can be divided into different types according to different conditions:
1.According to the different equipment used, it can be divided into: blast furnace method;submerged arc furnace method;electric arc furnace method;outside furnace method;vacuum resistance furnace method;oxygen converter method.
2.According to the process characteristics, it can be divided into:
(1)Solvent-free method: Carbonaceous materials are generally used as reducing agents, and slag-making materials are not added to adjust the composition and properties of the slag. For example, ferro silicon, silicon calcium alloy, silicon metal etc are smelted without slag.
(2)Solvent method: The reducing agent used can be carbonaceous material or silicon or other materials. The production is to add a solvent to make slag to adjust the composition and properties of the slag. Due to different production varieties, the commonly used solvents include lime, dolomite, fluorite, etc. Ferro chrome and ferro manganese are commonly smelted by this method.
3.According to the source of heat, it can be divided into:
(1)Carbothermal method: The heat source in the smelting process is mainly the combustion heat of coke, and part of the coke is also used as a reducing agent to reduce the oxides in the ore. The production is carried out in a blast furnace.
(2) Electrothermal method: The main source of heat if electricity, and carbonaceour materials are used as reducing agents to reduce the oxides in the ore, which is mainly carried out continuously in a submerged arc furnace, such as ferro silicon and ferro manganese.
(3)Electric silicon heating method: Use silicon or the silicide of alloying elements that need to be extracted as reducing agent to reduce the oxides in the ore. The heat generally comes from the chemical heat released during silicon oxidation, and the insufficient part is supplied by electric energy. Intermittent operation is used in electric arc furnace, such as low-carbon ferro manganese, RE alloy etc.
(4)Metal thermal method:The strong reducing agent aluminum particles and 75% ferro silicon powder are often used as the reducing agent, and sometimes as mixture of silicon and aluminum is used. Using silicon as main reducing agent is as the silicothermic method, and using aluminum as the main reducing agent becomes the aluminothermic method.
Anyang Huatuo Metallurgy has in various ferroalloys such as ferro silicon, silicon metal, ferro chrome, silicon calcium etc for more than 10 years, own rich experience in the products production and export, so if any confused just contact us.