Manganese is an essential element in the steel industry, and almost all steel contains a certain amount of manganese. Manganese can refine the grains of steel, improve the hardenability of steel, enhance the atmospheric corrosion resistance of steel, and improve the forgeability and rolling properties of steel. Electric furnace high carbon ferromanganese is a deoxidizer, desulfurizer and alloy additive for steelmaking. In 1774, Gane in Sweden used pyrolusite and charcoal to co-heat in a crucible and discovered manganese particles. In 1919, Dr. Carl William Soderberg of Norway invented the submerged arc furnace using self-forming electrodes.
Manganese
The traditional electric furnace high carbon ferromanganese process has a history of more than 100 years. Traditional electric furnace high-carbon ferromanganese smelting uses manganese ore as raw material, and uses coke to carry out carbon reduction in an electric heating ore thermal reduction furnace. It is an electrothermal process of continuous smelting and batch furnace extraction. Traditional smelting methods have problems such as high energy consumption and environmental pollution. Each ton of electric furnace high carbon ferromanganese consumes 450-550 kg of coke and 2500-3000 degrees of electricity.
Smelting high-carbon ferromanganese with an electric furnace, generally speaking, the higher the silicon content in the alloy, the lower the manganese content in the slag. However, when producing special high-carbon ferromanganese with a silicon content of less than 0.1%, it is necessary to control the Si content by reducing the amount of reducing agent. my country’s manganese ore is generally high-silicon, high-iron, and poor manganese ore. When smelting high-carbon ferromanganese, the Si content in the alloy is usually as high as 3-4%. , and require SiO2<26%. In order to have a certain recovery rate of Mn, the Si content in the alloy is usually controlled within the range of 1.5-2.5%.
The new high-carbon ferromanganese standard stipulates that the Si content of group 1 of electric furnace high-carbon ferromanganese is within the range of 1.5-2.5%. The production process of medium and low carbon ferromanganese with full hot charging and hot mixing is also called shaking bag electric furnace method, which is a long-flow ferromanganese production process with two furnaces and one bag. The whole production process requires the use of mineral heat energy generated by three main sets of equipment: silicon-manganese alloy furnace, refining electric arc furnace and shaking ladle. Among them, the shaking ladle, as the key production equipment, provides a strong guarantee for the production of high-quality medium and low carbon ferromanganese alloys, and is currently widely used in the production process of medium and low carbon ferromanganese hot charging mixing.
Manganese in the steel industry
At present, the traditional low-carbon ferromanganese smelting at home and abroad includes electric furnace method (electric silicon thermal method), shaking bag method, shaking bag-electric furnace method, oxygen blowing method, etc. according to different process methods and smelting equipment. , each has its own advantages. , but its common disadvantage is that the basic raw materials used are manganese ore and manganese-silicon alloy. The smelting process involves complex chemical reactions such as oxidation-reduction and multi-phase equilibrium, and often requires the addition of auxiliary charge/raw materials (such as slagging), so the process control factors are complex, the process flow is long, the system requires a lot of equipment, equipment investment is large, and the grade of the finished product is controlled And the disadvantages such as difficulty in raising and improving, high manganese content in waste residue (generally more than 8%), low manganese yield, serious environmental pollution, etc., cannot adapt to the increasingly fierce market competition and environmental protection requirements.