The raw materials for producing low-carbon ferromanganese include manganese-silicon alloy, ore, lime, fluorite, etc. The raw materials used in the oxygen-blowing decarburization method are mainly high-carbon ferromanganese. In order to produce low-carbon ferromanganese that meets the standard requirements and achieves good technical and economic indicators, all raw materials must meet specific quality requirements. The main production methods of low-carbon ferromanganese are the electric silicon thermal method, shaking furnace production method, oxygen blowing production method, Pollan method, and Udacon converter method. Raw material requirements: Manganese-silicon alloy is based on the electric silicon heating method and shaking table method to produce medium and low-carbon ferromanganese. Manganese-silicon alloy is required; manganese ore and low-carbon ferromanganese production need high manganese ore, low phosphorus-manganese ratio, and low silica content; Lime, lime for smelting low-carbon ferromanganese requires calcium oxide content greater than 85%.
Electric furnace high-carbon ferromanganese coal-to-synthesis gas production process, which does not use scarce coke, reduces power consumption, improves the environment, and improves product quality. A process for producing electric furnace high-carbon ferromanganese from coal-to-synthesis gas, comprising the following steps:
1) Preparation of coal-to-synthesis gas and ferromanganese ore pellets;
2) After the coal-based synthesis gas is purified and preheated, it is fed into the reaction shaft furnace from below, and the manganese ore pellets are fed into the reaction shaft furnace from the top. The coal-based synthesis gas contacts the falling manganese iron ore pellets to form metallization pellets;
3) Send the formed metalized pellets into the submerged arc furnace, add flux and a reducing agent to melt, separate slag and iron in the electric furnace, and produce high-carbon ferromanganese.
Coal-to-synthesis gas is produced by grinding raw coal into a fine powder and feeding it into a gasifier to react with oxygen-enriched and water vapour. In the generated coal-to-synthesis gas, the volume ratio of h2+co is ≥90%. Coal-to-synthesis gas purification refers to washing coal-to-synthesis gas with low-temperature methanol to remove acidic components in the raw gas. Coal-to-synthesis gas preheating refers to using the gas discharged from the reaction shaft furnace to preheat the coal-to-synthesis gas to ≥1100°C. Feeding the metallized pellets into the submerged arc furnace means that the reduced metallized pellets are continuously added to the submerged arc furnace through the heat transfer device, and the temperature of the metallized pellets added to the submerged arc furnace is kept above 600°C. The quicklime and anthracite entering the submerged arc furnace are preheated to over 600°C in the preheating kiln on the top of the submerged arc furnace before entering the submerged arc furnace. Slag-iron separation is to melt the metallized pellets in a submerged arc furnace to form high-carbon ferromanganese and slag in an electric furnace. At regular intervals, open the tap hole of the submerged arc furnace to separate the slag iron.
This process changes the traditional manganese ore submerged arc furnace smelting reduction process, does not use coke as a reducing agent, and avoids the pollution of the coking process in metallurgical plants; this process expands the smelting capacity of the submerged arc furnace by more than two times. The charge is heated to above 600°C and melted into the submerged arc furnace. When the charge temperature rises by 100°C, the power consumption of the electric furnace per ton of high-carbon ferromanganese is reduced by 70 degrees; the generation of particulate matter, sulfide, and nitrogen oxides are small, and it is clean and environmentally friendly; the process The electric furnace produced is high-carbon ferromanganese, with less harmful impurities and good quality. The high-temperature melting furnace can be a high-frequency, medium-frequency, or power-frequency induction furnace; the melting temperature of the high-temperature melting furnace is controlled from 1300°C to 1800°C. % range adjustment, the manganese content of low-carbon ferromanganese finished products can be adjusted within the range of 70% to 99.8%. The smelting process of the present invention basically does not involve complex chemical reactions, does not need to add another auxiliary charge/raw materials (such as slagging agent, coolant, etc.), has single process steps, greatly optimized product quality, high manganese content and large output, Low energy consumption, basically, no environmental pollution has broad market promotion prospects.