METAL SCRAP HEATING METHOD Russian patent published in 2015 - IPC F27D13/00 C22B1/248 

FIELD: metallurgy.

SUBSTANCE: invention relates to ferrous metallurgy, namely to steel making in electric arc furnaces. The metal scrap heating method for steel making in arc furnaces includes the use of a scrap heating chamber with a gas return circuit, gases are withdrawn from the top part of the chamber by means of recirculation smoke exhauster, and a part of return gases by means of the smoke exhauster of flue gases are supplied to a chimney and discharged into atmosphere. The method provides preparation of heat carrier in the heat generator by burning of natural gas with oxidiser which is obtained by mixing of part of return gases with oxygen, adding of the heat carrier together with another part of return gases into the bottom part of the scrap heating chamber, and also withdrawal from the output of the heat generator of a part of gases of the heat carrier where their temperature is sufficient for decomposition of dioxine, with their subsequent holding at this temperature, cooling by injected water down to the temperature excluding repeated synthesis of dioxine, and supply of the cooled heat carrier gases into the flue gas path with ensuring heat exchange with oxygen which is supplied for obtaining of the named oxidiser.

EFFECT: method allows to avoid emission of dioxine with flue gases, reduce consumption of natural gas for heat carrier preparation due to recovery of heat of flue gases to oxidiser, reduce water consumption cooling of flue gases due to reduction of yield of these gases because of recirculation, avoid steam explosions in the arc furnace.

1 dwg