METHOD OF MAKING STEEL IN OPEN-HEARTH FURNACE Russian patent published in 2005 - IPC

FIELD: steel making in open-hearth furnaces.

SUBSTANCE: proposed method includes charging metal burden into furnace pool, heating this burden, pouring molten cast iron, melting metal charge, bringing the properties of melt to required level, blowing the pool with flow of neutral or inert gas fed through layer of porous refractory material located on bottom along longitudinal axis of pool forming separate blast zones. Blowing the pool at charging and heating metal burden and pouring cast iron are performed at intensity ensuring specific density of blast in each blast zone equal to 0.5-1.8 m³/h per square meter of its surface. After pouring cast iron at melting of metal burden, pool is blown at intensity of 0.08-0.25 m³/h per ton of cast iron. At final melting of melt pool is blown at intensity of 0.01-0.1 m³/h per ton of melt maintaining blast density in separate blast zones equal to 3.2-5.5 m³/h per square meter of its surface. Intensity of blast in blast zones located in furnace center may exceed intensity of blast in extreme zones by 2-6 times.

EFFECT: increased output of furnace; reduced power requirements; reduced dust escape and slag emissions; improved quality of steel.

2 cl, 1 ex