Shaft furnace

Claim 2

In a shaft-furnace installation, in combination: a vertically extending shaft furnace of generally rectangular cross section; charging means including a housing surmounting said shaft furnace and provided with upper and lower closure members and charge-catching means intermediate said closure members for receiving an increment of charge upon opening of the upper closure member and emptying said increment of charge into said furnace upon opening of the lower closure members, said housing being formed with upper and lower horizontal frames, said closure members being formed as respective horizontally shiftable plates slidable in said frames, said charge-catching means including an upwardly converging horizontal chargedistributing member lying in a vertical median plane through said furnace, and a pair of outwardly and inwardly swingable flaps having horizontal pivotal axes within the outline of said charge-distributing member and disposed therebelow for temporarily retaining increments of charge in said housing, said flaps and said charge-distributing member having a plan outline in the outwardly swung positions of said flaps corresponding to the cross section of the upper end of said furnace; means for introducing a reducing gas into the bottom of said furnace and including a gas-distributing member mounted in said furnace at the bottom thereof extending longitudinally of the rectangular cross section of said furnace and substantially in said vertical median plane parallel to said charge-distributing member, and duct means for introducing said gas into said gas-distributing member at least at one end thereof; and discharge means at the bottom of said furnace including a downwardly converging hopper having a pair of downwardly converging longitudinal walls and a pair of vertical walls together defining a discharge opening of a maximum crosssectional area corresponding to the vertical projection of said gas-distributing member member, a horizontal support plate disposed below said discharge opening and spaced therefrom, and at least one horizontally shiftable discharge bar slidable along said support plate for laterally dispensing reduced charge from said furnace.

Claim 3

In a shaft-furnace installation, in combination: a vertically extending shaft furnace of generally rectangular cross section; charging means including a housing surmounting said shaft furnace and provided with upper and lower closure members, and charge-catching means intermediate said closure members for receiving an increment of charge upon opening of the upper closure member and emptying said increment of charge into said furnace upon opening of the lower closure member; means for introducing a reducing gas into the bottom of said furnace and including a gas-distributing member mounted in said furnace at the bottom thereof extending longitudinally of the rectangular cross section of said furnace and substantially in a vertical median plane therethrough, and duct means for introducing said gas into said gas-distributing member at least at one end thereof; and discharge means at the bottom of said furnace including a downwardly converging hopper having a pair of downwardly converging longitudinal walls and a pair of vertical walls together defining a discharge opening of a maximum cross-sectional area corresponding to the vertical projection of said gas-distributing member, a horizontal support plate disposed below said discharge opening and spaced therefrom, and at least one horizontally shiftable discharge bar slidable along said support plate for laterally dispensing reduced charge from said furnace, said gas-distributing member being formed as downwardly open through having upwardly converging frustoconical flanks defining a peak extending in the longitudinal dimension of the rectangular cross section of said furnace, said bar having a width ranging between 20 and 80 percent of the width of said discharge opening, said discharge opening having a cross secton substantially equal to the horizontal plan projection of said gas-distributing member and said bar having a transverse stroke of 30 to 50 percent of said width of said discharge opening, said housing being formed with upper and lower horizontal frames, said closure members being formed as respective horizontally shiftable plates slidable in said frames, said charge-catching means including an upwardly converging horizontal charge-distributing membeR extending parallel to said gas-distributing member in said vertical median plane, and a pair of outwardly and inwardly swingable flaps having horizontal pivotal axes within the outline of said charge-distributing member and disposed therebelow for temporarily retaining increments of charge in said housing, each of said flaps being formed with a shaft extending along the respective axis and shielded by said charge-distributing member, means coupling said shaft for joint rotation, and actuating means for angularly displacing at least one of said shafts.

Claim 4

In a shaft-furnace installation, in combination: a vertically extending shaft furnace of generally rectangular cross section; charging means including a housing surmounting said shaft furnace and provided with upper and lower closure members, and charge-catching means intermediate said closure members for receiving an increment of charge upon opening of the upper closure member and emptying said increment of charge into said furnace upon opening of the lower closure member; means for introducing a reducing gas into the bottom of said furnace and including a gas-distributing member mounted in said furnace at the bottom thereof extending longitudinally of the rectangular cross section of said furnace and substantially in a vertical median plane therethrough, and duct means for introducing said gas into said gas-distributing member at least at one end thereof; and discharge means at the bottom of said furnace including a downwardly converging hopper having a pair of downwardly converging longitudinal walls and a pair of vertical walls together defining a discharge opening of a maximum cross-sectional area corresponding to the vertical projection of said gas-distributing member, a horizontal support plate disposed below said discharge opening and spaced therefrom, and at least one horizontally shiftable discharge bar slidable along said support plate for laterally dispensing reduced charge from said furnace, said gas-distributing member being formed as downwardly open through having upwardly converging frustoconical flanks defining a peak extending in the longitudinal dimension of the rectangular cross section of said furnace, said bar having a width ranging between 20 and 80 percent of the width of said discharge opening, said discharge opening having a cross secton substantially equal to the horizontal plan projection of said gas-distributing member and said bar having a transverse stroke of 30 to 50 percent of said width of said discharge opening, said housing being formed with upper and lower horizontal frames, said closure members being formed as respective horizontally shiftable plates slidable in said frames, said charge-catching means including an upwardly converging horizontal charge-distributing membeR extending parallel to said gas-distributing member in said vertical median plane, and a pair of outwardly and inwardly swingable flaps having horizontal pivotal axes within the outline of said charge-distributing member and disposed therebelow for temporarily retaining increments of charge in said housing, each of said flaps being formed with a shaft extending along the respective axis and shielded by said charge-distributing member, means coupling said shaft for joint rotation, and actuating means for angularly displacing at least one of said shafts.

Claim 5

The installation defined in claim 2 wherein said flanks include an angle of substantially 40* to 50* with one another.

Claim 6

The installation defined in claim 2 wherein the width of said gas-distributing element in horizontal plan is about one-fifth to one-third of the width of said furnace at the bottom thereof.

Claim 7

The installation defined in claim 2 wherein said furnace widens progressively from its top to its bottom.

Claim 8

The installation defined in claim 2 wherein said housing has a pair of longitudinal downwardly converging walls and a pair of vertical end walls defining a discharge opening registering with the top of said furnace.

Claim 9

The installation defined in claim 6, further comprising conveyor means above said upper closure member and shiftable in the longitudinal dimension of the furnace cross section for introducing the charge increments into said housing.