Author: Publisher:
ISBN:
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Languages : en
Pages : 8
Book Description
British Patent : GB789093 : Improvements in Or Relating to the Production of Low Carbon Ferrochromium
Author: British Patent : GB1077665 : Improvements Relating to Paste for the Production of Carbon Bodies
Author: Improvements in Or Relating to the Production of Ferrochromium Alloys
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Conventional submerged arc furnaces produce in single stage smelting, ferrochromium alloys containing 4% to 8% carbon and 0% to 10% silicon. Alloys with less than 4% carbon are made in 2 or more stages and are expensive. This invention covers a process for producing ferrochromium alloys with less than 4% carbon in a single smelting stage. Finely divided chromite ore is prereduced with a carbonaceous reducing agent in a solid state process (1300 degrees C to 1700 degrees C) and thereafter the 40% plus prereduced ore is smelted (without further addition of reductant) with fluxes to provide slag and metal phases. Process works with only 20% excess carbon but patent claims less than 50%; also that non-carbonaceous reducing agents such as ferrochromium silicide, to improve chromium recovery from the slag can be used. Prereduction is normally 50% to 70%. Residual carbon figures of 2% were commonly realised during the laboratory work.