The method of refining silicon outside the furnace with high resistivity

Silicon metal is a high-energy-consuming product, and energy-saving work is very important. The main energy-saving methods are: (1) Careful selection of materials. The choice of carbonaceous reducing agent and silica has a great influence on power consumption and output. Sometimes there is a contradiction between quality and power consumption. We must balance the gains and losses. For example, if you use petroleum coke or all of it, the quality will improve, but the power consumption will increase significantly. If you use bituminous coal or charcoal, the power consumption will decrease, but the quality will be affected.

The method of refining silicon outside the furnace with high resistivity reducing agents such as bituminous coal under the condition of ensuring quality can reduce power consumption. The selection of high-quality silica is also very important, not only the chemical composition of silica, but also the smelting performance, such as thermal stability, reduction and other indicators. (2) Elaborate design of electric furnace parameters. Improper selection of electric furnace parameters, such as excessive voltage selection will increase power consumption. The design of furnace size must consider the use of graphite electrodes for the production of metal silicon. It is not appropriate to use graphite electrode diameter as the calculation basis, but the furnace size should be calculated according to the carbon electrode diameter. According to the experience of a certain factory,

the secondary voltage of the 1800kVA three-phase electric furnace is 84V, and the polar center is 1150mm. (3) Large-capacity electric furnace production. According to domestic statistics, the power consumption of electric furnaces above 5000kVA is generally in the range of 12000~14000kVA/t. Due to the large proportion of heat loss in small electric furnaces, the power consumption is high, generally in the range of 14000 ~ 17000kVA/t. The American Hanna Mining Company expanded the capacity of the 9000kVA electric furnace to 12000kVA to achieve a 12% improvement in daily output, an 8% improvement in silicon recovery rate, and a 5% reduction in power consumption. (4) It is produced by the rotary electric furnace of the furnace body.