METHOD FOR PRODUCTION OF LOW-CARBON FERROCHROME Russian patent published in 2016 - IPC C22C33/04 C21C7/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy and can be used in production of low-carbon varieties of ferrochrome. Method uses charge in form of homogenised mixture of crushed materials at ratio (%): chromium concentrate, lime and ferrosilicon 75 % (45-44):(40-44):(15-12) respectively, ferrochrome is released from electric furnace with carbon content 0.08-0.20 % and its vacuum oxygen decarburisation in ladle to carbon content 0.03-0.01%. With carbon content in range of 0.08-0.20 % ferrochrome is first blown from above with gaseous oxygen at flow rate of 0.3-0.7 m³/(t·min) at residual pressure in range of 6.70-1.33 kN/m² to obtain [C] = 0.05-0.06% and temperature 1,720-1,760°C, then oxygen blowing is terminated, residual pressure is decreased to 0.130-0.067 kN/m² and ferrochrome decaburised without oxygen blowing to obtain 0.03-0.01 % [C].

EFFECT: invention ensures reducing carbon content in obtained ferrochrome up to 0,03 -0,01% without significant oxidation of chromium, and also reduce power consumption and obtaining content of chromium in ferrochrome more resistant to melting.

1 cl, 4 dwg, 2 ex