Process and device for recovering complementary energy of silicon smelting furnace

Abstract

The invention discloses a process and device for recovering complementary energy of a silicon smelting furnace. The process part can be used for recovering the complementary energy by heat-absorbing radiation, air cooling, heat tube heat exchange and other modes; the device part mainly comprises a membrane type water-cooling wall heated surface, a fan, a waste heat boiler, a steam turbine, a generating unit and the like; a radiation heated surface is arranged in a clearance area of two layers of hearths; a blower is connected with an air inlet at the lower part of the clearance area of the two layers of hearths by a pipeline; the waste heat boiler is connected with a flue gas outlet of a furnace mantle through a pipeline; and an exhaust pipeline of the waste heat boiler is connected with a dust remover. By arranging the radiation heated surface, the exhaust temperature of a hearth of the silicon smelting furnace can be reduced, an electrode of the silicon smelting furnace can be protected and the exhaust heat of the silicon smelting furnace can be recovered; by blowing cold air into the lower parts of two layers of spaces of the silicon smelting furnace, the smoke temperature of the hearth can be reduced again and the electrode can be protected; the exhaust waste heat of the silicon smelting furnace system can be recovered by using the waste heat boiler so as to further reduce the heat loss of the exhausted smoke of the smelting furnace; and the generation utilization of the recovered waste heat of the system can be realized by adopting the generating unit of the steam turbine.

Description

technical field [0001] The invention relates to the field of new energy and high-efficiency energy-saving technologies, in particular to a silicon smelting furnace residual energy recovery process and a device thereof. Background technique [0002] Silicon metal is the core material of the solar photovoltaic power generation industry. Metal silicon is the product of reduction reaction between quartz sand (silicon dioxide) and carbon (clean coal, wood, etc.) in an electric arc furnace under high temperature conditions. The production process of metal silicon is to put coal, charcoal, silica and other raw materials into the electric arc furnace, provide instantaneous high temperature through arc discharge, melt silicon dioxide, and reduce it with carbon or graphite. [0003] The production of silicon metal in my country began in 1957. There were only a dozen production units in the early stage, and the production capacity was very small. In recent years, with the application ...

AI Technical Summary

Problems solved by technology

During the reduction reaction process of the electric arc furnace, a large amount of heat energy is directly lost from the open part of the furnace to the surrounding atmosphere through radiation and convection; The chimney is directly discharged into the atmosphere, and the chemical energy carried by it has not been effectively utilized, resulting in a low utilization rate of heat energy in the silicon smelting furnace system as a whole

According to calculations, the thermal energy utilization rate of my country's small and medium-capacity industrial silicon furnaces is generally only about 50% to 65%.

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