SU259097A1 - ROUGHED MINE OVEN - Google Patents

Description

The invention relates to the field of production of sponge iron, and can also be used in other areas for technological processes, when the lumpy material being processed is retained in solid form and the structure of the layer does not change.

Known shaft furnaces for industrial production of sponge iron, which have small transverse dimensions and small working volume, and as a result, small productivity. The reason for limiting the shaft dimensions of shaft furnaces is the difficulty of evenly distributing ino gas to a cross section with a pile of conventional tuyeres located on the periphery of the furnace.

In order to increase productivity, a combined mine bed is proposed, in which, at the point of transition from the upper shaft to the lower one, elongated by 1.5–3.0 m and inclined are 1 at an angle of 50–75 ° to the horizontal of the tuyere; the number of tuyeres is equal to 0.9-1.2 diameter "kiln, expressed in meters.

FIG. 1 shows the described combined shaft furnace; “And FIG. 2 and 3 - possible installation of tuyeres.

The furnace contains the boot device 1 (according to the type of the blast furnace of the blast furnace); gas outlets 2 of the exhaust gas; upper shaft 3 for heating and partial reduction

material; 4; elongated and steeply tucked 5 tuyeres for the supply of hot reducing gas to the bed; bottom shaft 6 for final material recovery and cooling of the finished product; agitators, lumps 7, supporting a layer of material; furnace cooling zone 8; a device 9 for supplying a cold reducing gas to the cooling zone; unloading machine 10.

A reducing gas with a temperature of about 1000 ° C under a pressure of 3-4 bar is supplied to the central region of the mine with tuyeres. Placing in the lower mine elongated by 1.5-3.0 m and inclined at 50-75 ° to the horizontal tuyeres, whose mouth is removed from the walls of the lower mine by 1.0-2.0 m, ensures a uniform distribution of gas throughout the section as lower and upper mines. Tuyeres are installed at the transition point from the top to bottom, and the top of the tuyeres is fixed by a circle, the diameter of which is about half the diameter of the upper shaft.

When removing the mouth of the tuyeres from the walls of the mine to the distance to the base gauge of pieces of material, the negative influence of the wall on the distribution of the gas tract over the furnace cross section is minimized, and the gas flow in the lower shaft is distributed evenly to the cross section of the furnace. In addition, the risk of the formation of wards and eagles between the tuyere and the wall of the shaft is reduced.

Preliminary calculations show that for a 700 kiln shaft furnace, the height of the tuyeres is about 1000-1500 mm, but not more than 2000 mm. When the layer of tuyeres with high and horizontal horizontally up to 1250 mm (for a furnace of 700 m), the pressure of the column of material of the upper shaft on the tuyeres is practically excluded. In case of insufficient stability of the tuyere with a height of about 2000 mm, a special water-cooled support structure is used (see Fig. 3). In the case of sharp tufts, delays of gathering material and the formation of wall accretions are excluded; on the walls of tuyeres.

The dotted line in FIG. 1 profile of the upper shaft is provided for the case of difficulty in gathering material in the area of the upper shaft split.

Subject invention

A combined shaft furnace consisting of two mines interconnected in one above the other, in which the diameter of the lower shaft is larger than the diameter of the upper shaft, characterized in that, in order to increase the productivity of the furnace, at the transition point from the upper shaft; installed elongated by 1.5-3.0 m and inclined at an angle of 50-75 ° to the horizontal tuyere, the number of which is 0.9-1.2 of the diameter of the furnace, expressed in meters.

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