GB2076511A - High-temperature reduced iron production - Google Patents

Abstract

High-temperature reduced iron production uses either a hot charging installation for charging reduced iron produced by a reduction furnace directly into a steel making furnace, or a storage tank for the reduced iron fed from the reduction furnace, and a briquetting plant associated with the storage tank. If the briquetting plant is remote from the furnace the reduced iron may be transported between them via a transportable container. According to one aspect of the invention, a reduced iron installation is characterized in that a transportable container 1 has a charge/discharge mouth section 1a provided with a sealing valve 6 and a plurality of support legs 2 and is arranged for 180 DEG rotation between a charge condition under the furnace to a discharge condition supported over the mouth of a storage tank 13 via its legs, a weighing device for said container in its discharge condition, and a cluster remover 8 disposed in the storage tank mouth and having a sealing valve which opens and closes, respectively, in response to detection signals from said weighing device indicating that said container is charged or empty. Another aspect of the invention provides a cluster remover comprising a grizzly feeder disposed obliquely within a cylindrical casing which is supported via an anti-vibration mounting on a fixed support surface, and a vibrating machine mounted on said casing. <IMAGE>

Description

SPECIFICATION High-temperature reduced iron prod.uction The present invention relates to hightemperature reduced iron production in which there is provided either a hot charging installation for charging reduced iron produced by a reduction furnace directly into a steel making furnace, or a storage tank for the reduced iron remote from the reduction furnace, and a briquetting plant associated with the storage tank.

Heretofore, in the case of briquetting hightemperature reduced iron, the briquetting plant has been directly coupled to the reduction furnace through a connecting pipe. However, since the briquetting plant must be installed under the reduction furnace there is a disadvantage that the overall height of the furnace is extremely high.

An object of the invention is to eliminate the above-described disadvantage in the prior art by providing a high-temperature reduced iron installation in which the briquetting plant is remote from the furnace and the reduced iron is transported from the furnace to the plant via a transportable container in an efficient manner.

Another object of the invention is to provide effective means for removing clusters contained in the high-temperature reduced iron.

According to one aspect of the invention, a high-temperature reduced iron installation is characterized in that said installation includes a transportable container for transporting reduced iron produced in a furnace to à storage tank remote from said furnace, said container comprising a mouth defining a charge/discharge section provided with an opening and closing valve which preserves fluid-tightness when closed and a plurality of support legs and said container being arranged for rotation through 1 800 between a charge condition with its mouth uppermost for receiving reduced iron from said furnace to a discharge condition with its mouth lowermost and adapted to be supported over a mouth of the storage tank via said support legs, a weighing device arranged to be interposed between said container and said storage tank when the container is in its discharge condition, and a cluster remover having means for fluid-tight connection to the mouth of said container in said discharge position, said cluster remover being disposed in the mouth of the storage tank and being provided with a sealing valve which is adapted to be opened and closed, respectively, in response to detection signals from said weighing device indicating that said container is charged or empty.

According to a second aspect of the invention a cluster remover for removing clusters formed in the course of producing high-temperature reduced iron is characterised in that a grizzly feeder is disposed obliquely within a cylindrical casing, through which the reduced iron is fed from a reduction furnace, said cylindrical casing being supported via an anti-vibration mounting on a fixed support surface, and in that a vibrating machine is mounted on said casing and operable to vibrate said grizzly feeder with respect to said fixed support surface.Where the cluster remover is to be used in a high temperature reduced iron installation according to the first aspect of this invention, the cylindrical casing with the grizzly feeder disposed therein is provided within the mouth of the storage tank for receiving the hightemperature reduced iron and is connected to said storage tank via an expansion joint, and a freely openable hatch for discharging clusters separated from the reduced iron is provided on said casing adjacent the lower end of said grizzly feeder, and also a cluster discharging chute is provided adjacent said hatch.

In the following, the present invention will be described in greater detail in connection to a preferred embodiment thereof with reference to the accompanying drawings, in which: Figure 1 is a conceptional flow sheet of a hot briquetting installation, of a kind having a transportable container for transporting reduced iron from a furnace to the briquetting plant.

Figure 2 is a longitudinal cross sectional view of the transportable container shown connected to the charge end of a storage tank of the briquetting plant.

Figure 3a is a view similar to Figure 2 of the charge end of the storage tank of the briquetting plant, showing further details of a cluster remover disposed therein, and Figure 3b is a plan view of Figure 3a.

Referring to Figure 1, reference character A designates a reduction furnace, and numeral 1 designates a transportable container for transporting and charging high-temperature reduced iron produced by the reduction furnace A to the interior of a high-temperature reduced iron storage tank 13 of a briquetting plant installed at a location remote from the reduction furnace A and provided with a briquetting machine M thereunder.

Referring now to Figure 2, in the preferred embodiment of the invention, the transportable container 1 comprises a reduced iron charge/discharge section 1 a provided with a double-door type valve 6, a reduced iron storage section 1 b and a plurality of support legs 2. After charging the container 1 with high-temperature reduced iron from the reduction furnace A, through the reduced iron charge/discharge section 1 a (i.e. with the container mouth uppermost and the valve 6 open) and into the reduced iron storage section 1 b under the condition shown on the right hand side of Figure 1 , the valve 6 is closed and made fluid-tight, the container 1 is transported by a crane or other suitable equipment to the briquetting plant, rotated through 1 800 and located on a support surface 3 of the storage tank 13 via the support legs 2. The support surface 3, is, in turn, supported from a fixed equipment deck 5, via a weighing device 4. Between the support surface 3 and the mouth of the storage tank 1 3 there is provided a cluster remover of annular form, which is supported'from the equipment deck 5 via a support frame 10 and provided with an inclined grizzly feeder 8 as described in more detail hereinafter with reference to Figures 3a and 3b.The upper opening of the cluster remover 9 has an annular groove 7, which is filled sand or like material, so that when the container 1 is lowered onto the support surface 3 via its support legs 2 as described above, the rim of the mouth of the reduced iron charge/discharge section la of the container 1 sinks into the sand and, thereby, is connected to the cluster remover in a fluid-tight manner. A hatch 11 is mounted at an appropriate location on the side wall of the cluster remover 9 adjacent the lower end of the inclined grizzly feeder so as to be freely opened and closed by the actuation of appropriate drive means such as, for example, a hydraulic cylinder 11 a, and a cluster discharge chute 12 for discharging clusters (i.e.

sintered blocks of reduced iron of approximately 10-30 cm in diameter, which tend to be formed in the course of production of the reduced iron) separated from high-temperature reduced iron by the grizzly feeder 8 in the cluster remover 9 mounted adjacent the hatch 1 The bottom opening of the cluster remover 9 is fluid-tightly connected to a hopper-like section 1 3a provided in the mouth of the storage tank 13 via an expansion joint 14. A damper type sealing valve 15 is provided, as shown in Figure 2, to open and close the bottom opening of the hopper-like section 1 3a.The sealing valve 15 can be controlled by any appropriate control means (not shown) which are operable to open said valve in response to a detection signal from the weighing device 4 when the container 1 charged with reduced iron is set down on the support surface 3 as shown in Figure 2; the valve 1 5 is closed by the control means in response to a signal from the weighing device 4 when the container 1 has been emptied.

After the container 1 has been emptied, and the valve 1 5 closed in response to a signal from the weighing device 4, the hatch 11 is opened by actuating its hydraulic cylinder 11 a, and the clusters separated by the grizzly feeder 8 are discharged through the discharge chute 1 2.

Subsequently, after closing the double-door type valve 6 in the container 1, the container 1 is once more rotated back through 1 80C and transported back to its charging location beneath the reduction furnace A to be ready for receiving the next batch of high-temperature reduced iron.

The high-temperature reduced iron from which the clusters have been removed, and which has been charged into the storage tank 13, as described above, is briquetted by the briquetting machine M (see Figure 1) disposed under the storage tank 13, and thereafter the shaped briquettes are removed.

Referring now to Figure 3a and 3b, in more detail, the grizzly feeder E is lattice- or gratingshaped and its mesh is selected so that normal reduced iron supplied from the container (as shown by the arrow) can easily pass therethrough.

The cylindrical casing 9' of the cluster remover 9 for supporting the grizzly feeder is fixedly secured to the support frame 3, which is, in turn, fixed via the support frame 10 and an anti-vibration rubber piece 1 7 to the equipment deck 5 of the storage tank 13. The casing 9', itself, is connected at its lower end to the storage tank 1 3 via an expansion joint 14 as described hereinbefore.

Again, as described hereinbefore, the casing 9' is provided with a hatch cover 11, which can be freely opened and closed by means of a hydraulic cylinder 11a and a discharge chute 12 beneath and adjacent said hatch cover.

In addition, on the casing 9' an electromagnetic type or mechanical type of vibrating machine 1 6 is mounted, the mounting position for which can be selected arbitrarily at any point around the circumference of the casing.

In use, reduced iron transported by the container 1, (or in the case of a hot charging installation, directly from the reduction furnace) passes through the grizzly feeder 8, and into the storage tank 13 which can be kept air-tight by the sealing valve 1 5 described hereinbefore. Clusters a contained in the reduced iron, which would be a hindrance to the manufacturing of briquettes should they be thrown into the storage tank 13, remain on the grizzly feeder 8, and when the hatch cover 11 is opened by the cylinder 11 a, they are discharged through the discharge chute 12.

Separation between the reduced iron and the clusters can thus be effected efficiently by means of the vibrating machine 1 6. However, the vibration of the casing 9' is damped by the antivibration rubber piece provided, and thus propagation of the vibration to the storage tank 13 is prevented by the expansion joint 14.

Since both the high-temperature reduced iron installation and the cluster remover therefor, according to the present invention, have the above mentioned constructions and effects, the present invention can provide advantages over the prior art as discussed hereinbefore, and moreover, the present invention can achieve the practical effect that high-temperature reduced iron free from clusters can be obtained under perfect conditions, since it is isolated from external, ambient conditions. Consequently, hot briquettes of excellent quality can be obtained.

It will be appreciated from the foregoing that, particularly with regard to the cluster remover, the present invention is also applicable to a hot charging installation in which high-temperature reduced iron is continuously charged directly to an electric furnace.

It will also be appreciated that by providing an inclined grizzly feeder within the cluster remover as described above and providing vibrating means externally on its casing, reduced iron can pass efficiently through the casing and it is not blocked by clusters on the grizzly feeder, since they gravitate to the lower end of said feeder. Thereby, the clusters can be removed at a high efficiency via the discharge chute 1 2.

Claims (5)

1. A high-temperature reduced iron installation, characterized in that said installation includes a transportable container for transporting reduced iron produced in a furnace to a storage tank remote from said furnace, said container comprising a mouth defining a charge/discharge section provided with an opening and closing valve which preserves fluid-tightness when closed and a plurality of support legs and said container being arranged for rotation through 1 80C between a charge condition with its mouth uppermost for receiving reduced iron from said furnace to a discharge condition with its mouth lowermost and adapted to be supported over a mouth of the storage tank via said support legs, a weighing device arranged to be interposed between said container and said storage tank when the container is in its discharge condition, and a cluster remover having means for fluid-tight connection to the mouth of said container in said discharge position, said cluster remover being disposed in the mouth of the storage tank and being provided with a sealing valve which is adapted to be opened and closed, respectively, in response to detection signals from said weighing device indicating that said container is charged or empty.

2. A cluster remover for removing clusters formed in the course of producing hightemperature reduced iron, characterized in that a grizzly feeder is disposed obliquely within a cylindrical casing, through which the reduced iron is fed from a reduction furnace, said cylindrical casing being supported via an anti-vibration mounting on a fixed support surface, and in that a vibrating machine is mounted on said casing and operable to vibrate said grizzly feeder with respect to said fixed support surface.

3. A cluster remover according to Ciaim 2 for removing clusters formed in the course of producing high-temperature reduced iron, in a high temperature reduced iron installation according to Claim 1, characterized in that the cylindrical casing with the grizzly feeder disposed obliquely therein is provided within the mouth of the storage tank for receiving the hightemperature reduced iron and is connected to said storage tank via an expansion joint, and in that a freely openable hatch for discharging clusters separated from the reduced iron is provided on said casing adjacent the lower end of said grizzly feeder, and in that a cluster discharging chute is provided adjacent said hatch.

4. A high-temperature reduced iron installation substantially as hereinbefore described with reference to, and as shown in, Figures 1 and 2 of the accompanying drawings.

5. A cluster remover for removing clusters formed in the course of reducing high-temperature- reduced iron substantially as hereinbefore described with reference to, and as shown in, Figures 2, 3a and 3b of the accompanying drawings.