Kawasaki Steel Corporation

Jfe Steel Corporation

Yoshitaka Sawa

Kanji Takeda

Tetsuya Yamamoto

Tatsuya Ozawa

Tetsuya Kikui

Tomoya Koseki

Natsuo Ishiwata

Kenji Ichino

Hiroshi Itaya

A method for discharging a reduced product produced on a movable hearth of a movable-hearth furnace uses a discharging device. The discharging device includes a removal unit for removing the reduced product from the movable hearth, a separation unit for separating the reduced product from a solid reductant, a leaving-returning unit for either leaving substances other than the reduced product on a solid reductant layer or returning the substances onto the solid reductant layer, and a discharge unit for discharging the reduced product to the outside of the movable-hearth furnace.

Method for discharging reduced product from a movable-hearth furnace and a discharging device

The invention provides a method and apparatus for charging a raw material and a carbonaceous material, in which a reduced product generated on a hearth can be quickly melted for reliable separation into a metal and slag, and the metal and the slag can be easily discharged out of a furnace as individual small agglomerates. With the charging method and apparatus, when charging the raw material and the carbonaceous material onto the moving hearth of the moving hearth furnace, the carbonaceous material is first charged onto the moving hearth to form a carbonaceous material layer thereon. The raw material or a mixture of the raw material and a carbonaceous material is then charged onto the carbonaceous material layer to form a raw material layer thereon. A projection is then pressed against the raw material layer from above, thereby forming a plurality of recesses in the surface of the carbonaceous material layer.

Method and apparatus for charging raw and carbonaceous materials into a moving hearth furnace

Traveling hearth furnace and an operating method thereof, which, when stacking a layer consisting of a mixture of oxides such as fine iron ore and a fine solid reducing material onto a horizontally traveling hearth and reducing the oxides through radiant heat transfer from above the hearth, is based on melting the reduction product in the course of up to a discharge port, and causing aggregation and separation of slag in from the reduction product, followed by solidifying the reducible material.

Rotary hearth furnace for reducing oxides, and method of operating the furnace

A mixed layer of fine ore and coal char and a layer of fine coal are stacked on a hearth in the form of separate layers from each other. The fine ore is reduced while fine coal is pyrolyzed to produce coal char. The produced coal char is used repeatedly.

Method of operating rotary hearth furnace for reducing oxides

With a solid fine reducing material containing hydrogen placed as a lower layer on a movable hearth, a powdered mixture of an oxide powder dominantly of a fine iron ore and a solid fine reducing material is stacked in layered arrangement, and subsequent reduction operation is performed.

Method of reducing iron oxide on a movable hearth furnace

A traveling hearth for producing reduced metal by charging and stacking a raw material containing a metal-containing material and a solid-reducing material on a horizontally moving hearth, arranged for disposing a solid-reducing material layer on the hearth, forming concave portions at the solid-reducing material surface, stacking the raw material on the surface of the solid-reducing material layer, reducing the raw material by at least once heating and melting the material on the hearth to separate metal and gangue and ash ingredients, and discharging metal from the hearth.

Method of producing a reduced metal, and traveling hearth furnace for producing same

Rotary hearth furnace and method of operating the same

Producing reduced metal by charging and stacking a raw material containing a metal-containing material and a solid reducing material on a horizontally moving hearth of a traveling hearth furnace, by disposing a solid reducing material layer on the hearth, forming concave portions at the solid reducing material surface, stacking the raw material on the surface of the solid reducing material layer, reducing raw material by at least once heating and melting the material on the hearth to separate metal and gangue and ash ingredients, and discharging metal from the hearth.

Method of producing a reduced metal, and traveling hearth furnace for

A roll outer layer material for hot rolling includes, as analyzed in weight percent, of 2.5-4.0% C, 6.0-20% Cr, 3.0-10.0% V, 0.6-5.0% Nb, 2.0-15% Mo, 3.0% or below Si, 3.0% or below Mn, C, V, Nb and Cr satisfying a following formula (1),

Method of manufacturing roll for hot rolling

Centrifugal cast roll shell material

A roll outer layer material for hot rolling consists essentially, as analyzed in weight percent, of 2.5-4.0% C, 6.0-20% Cr, 3.0-10.0% V, 0.6-5.0% Nb, 2.0-15% Mo, 3.0% or below Si, 3.0% or below Mn, C, V, Nb and Cr satisfying a formula where 10.5.ltoreq.6.5.C(%)--1.3.V(%)--0.7.Nb(%).ltoreq.2.Cr(%)--2, and the balance being Fe and incidental impurities. A method of manufacturing a roll for hot rolling comprises the steps of centrifugally casting an outer layer material having the above composition, centrifugally casting graphite steel containing 0.5% or above of C as an intermediate layer, and casting an axis material which is a spheroidal graphite cast iron, a flake graphite cast iron or a graphite steel. Carbon is present in the intermediate layer in an amount which satisfies a formula, C (intermediate layer).gtoreq.2.0-0.5�C(%)--0.2.V(%)--0.11.Nb(%)! (outer layer).

Growing community of inventors

Chiba, Japan

Yoshitaka Sawa