Production of low carbon chromium iron alloys from chromite concentrates
AssigneeKwg Resources, Inc.
InventorFrank Winter
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Abstract
A process for producing low carbon chromium iron alloys directly from chromite concentrates wherein superheated liquid aluminum is flowed in a controlled manner into a reaction vessel preheated to a temperature of approximately 1,000° C. while simultaneously feeding chromite concentrates preheated to a temperature in the same range at a controlled rate into the preheated reaction vessel. The ratio of chromite to aluminum is controlled to be at or above the stoichiometric ratio required to reduce the oxide from chromium and iron to low carbon ferrochrome alloy. Burnt lime is continuously added to the vessel in an amount sufficient to form and flux a slag of the eutectic composition known as calcium aluminate.
Claims13
A process for producing low carbon chromium iron alloys from chromite concentrates, comprising;
- flowing superheated liquid aluminum in a controlled manner into a reaction vessel preheated to a temperature in the range of approximately 800° C. to 1150° C. while simultaneously feeding chromite concentrates preheated to a temperature in the range of approximately 800° C. to 1150° C. at a controlled rate into said preheated reaction vessel, the ratio of chromite to aluminum being controlled to be at or above the stoichiometric ratio required to reduce the oxides of chromium and iron to low carbon ferrochrome alloy;
- continuously adding burnt lime to said vessel in an amount sufficient to form and flux slag in said reaction vessel, and thereby reacting the liquid aluminum with the preheated chromite concentrates to form liquid low carbon chromium iron alloy beneath said slag;
- and
- periodically removing liquid low carbon chromium iron alloy from beneath said slag in said vessel.
Dependencies are inferred from the claim text.