- Jun 10, 2018 -
What the main ways of energy saving of metal silicon?
￼Metal silicon is a product with high energy consumption. Therefore, energy saving is very important. The main energy saving methods are:
(1) Careful choice of materials. The choice of carbonaceous reducing agent and silica has a great impact on power consumption and production.
Sometimes there is a conflict between quality and power consumption. For example, if petroleum coke is used in large quantities or all, although the quality is improved, the power consumption will increase significantly.
With bituminous coal or charcoal, the power consumption will be reduced, but the quality will be affected. Using the method of refining silicon outside the furnace to match some bituminous coal and other high-resistivity reductants under the condition of ensuring quality can reduce the power consumption.
The choice of high-quality silica is also very important, not just the chemical composition of silica, but also the smelting properties, such as thermal stability, reducibility and other indicators.
(2) Elaborate design of electric furnace parameters. Improper selection of electric furnace parameters, such as high voltage selection will increase power consumption. The furnace size must be designed to consider the use of graphite electrodes for the production of metallic silicon. It is not appropriate to calculate the diameter of the graphite electrode, but the size of the furnace should be calculated based on the diameter of the carbon electrode. According to the experience of a plant, the secondary voltage of the 1800kV-A three-phase electric furnace is selected to be 84V, and the extreme heart circle selection is 1150mm.
(3) Production with large capacity electric furnaces. According to domestic statistics, the power consumption of electric furnaces above 5000 kV?A is generally in the range of 12,000 to 14,000 kV?A/t. Small electric furnaces account for a large proportion of heat loss and high power consumption, generally in the range of 14,000 to 17,000 kV?A/t. The Hanna Mining Company expanded the capacity of the 9000 kV-A electric furnace to 12,000 kV?A to achieve a 12% improvement in daily production, a 8% improvement in the silicon recovery rate, and a 5% reduction in electricity consumption.
(4) Furnace rotary furnace production.
In 1977, Aerken company in Norway studied the success of two rotating furnaces, which can prevent the crust of the furnace from automatically sinking. The test result of a 9000kV?A electric furnace was reduced by 10% to 14%.
(5) Using briquette charge. The agglomerates made of silica and reducing agent are prereduced in a furnace heated with heavy oil or gas and fed into an electric furnace. The unit's unit power consumption is below 9000 kW?h.
(6) Use semi-closed electric furnace to recover the heat energy of flue gas.
(7) Adopt refined silica technology outside the furnace to improve the product quality, so that the remaining small particles of metal silicon can be remelted and used for remelting to achieve the purpose of improving output and reducing power consumption.
(8) Carefully manipulated. Including the correct weighing of ingredients, grasp the amount of carbon, timely feeding is not empty, the furnace is deep and thick, so that the electrode deep insert stable insert, there is a good furnace conditions to achieve high quality, low consumption, high yield.