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US 4,063,930 AGranted
Preparation of weatherable ferrite agglomerate
AssigneeRepublic Steel Corporation
InventorsRobert Ernest Kusner, Robert William Muthig
Life of this patent
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AssigneeRepublic Steel Corporation
InventorsRobert Ernest Kusner, Robert William Muthig
Estimating the term…
A weatherable ferrite agglomerate is prepared by establishing compacted or other coherent bodies consisting of a mixture of fine particles of lime and of iron oxide, and heating the bodies, in a reducing atmosphere, at a suitable temperature up to about 2100.degree. F; under these circumstances, the lime and iron oxide react to form dicalcium ferrite, yeilding agglomerate bodies that are useful for furnace feed, as for a blast furnace. The iron oxide may conveniently consist of one or more waste oxides from iron and steel making operations, and the lime can be supplied as limestone, with a preliminary heating of the mixture, before or after forming the coherent bodies, to calcine the stone to lime. The agglomerate is advantageous in providing a way of using waste iron values and of supplying lime as such, for furnace operations, with practicality because of the weatherability which ordinary (calcined) lime does not have, while avoiding difficulties of making sintered bodies or the like.
Lime-iron oxide agglomerate consisting of weatherable, hard, non-fused and non-sintered bodies each having a mean diameter of at least about 1/4 inch, each being a strongly coherent body consisting essentially of iron values and lime, said lime being substantially all present in the form of dicalcium ferrite constituting a coherent structure throughout the body and produced by heating coherent intermixed fine particles of lime and iron oxide at a temperature of about 1650.degree. F to about 2000.degree. F in reducing environment, said bodies being thereby produced, to comprise said dicalcium ferrite, by heating only at temperatures substantially below sintering temperature, said lime being about 15 to 40% of the bodies and said iron values being present at least in sufficient amount to constitute the iron content of said dicalcium ferrite.
A method of producing a lime-containing iron oxide agglomerate product comprising establishing a coherent mixture of finely divided lime and finely divided iron oxide, said iron oxide being present at least in sufficient amount so as to provide a sufficient quantity of iron values thereof which can react, in ferrous state, with substantially all of the lime, and heating said coherent mixture, while maintaining the mixture in a reducing environment for establishing said sufficient quantity of iron values in ferrous state, at a sufficient temperature in the range of about 1650.degree. to 2100.degree. F and for a sufficient time, to cause said iron values, while in ferrous state, to react with substantially all of the lime to produce dicalcium ferrite throughout the product.
A method of producing a lime-containing iron oxide, strong agglomerate body comprising establishing a coherent body which is composed of a mixture of finely divided lime and finely divided iron oxide, said iron oxide being present in at least sufficient amount so that substantially all of the lime can react with iron oxide to produce dicalcium ferrite, and heating said coherent body, in a reducing environment, at a sufficient temperature in the range of about 1650.degree. to 2000.degree. F and for a sufficient time to cause substantially all of the lime to react with iron oxide to produce dicalcium ferrite constituted in and throughout said coherent body.
Dependencies are inferred from the claim text.