JPS61257413A - Sealing device between converter throat and skirt of converter waste gas treatment device - Google Patents

Abstract

PURPOSE:To provide thorough sealing between a converter throat and skirt and to increase the purity of a recovered waste gas by ejecting a refrigerant to the throat surface from the nozzles of a hollow cylindrical sealing ring made of a heat resistant cast iron provided to the bottom end of the skirt. CONSTITUTION:The sealing ring 18 made of the heat resistant cast iron having the hollow cylindrical section is provided to the bottom end of the skirt 2 of a converter waste gas treatment device and the many refrigerant ejection nozzles 19 communicating with the hollow part 20 of the ring 20 are provided thereto. The skirt 2 is lowered by the operation of a cylinder 12 via an annular supporting beam 17 to bring the ring 18 into right contact with the throat 1a surface of the converter 1; at the same time, an outside sealing ring 21 is lowered by a cylinder 22 so as to contact tightly with the throat 1a by which both sealing rings are connected with the bellows. The refrigerant is then ejected onto the throat 1a surface from the above-mentioned nozzles 19 to prevent the sticking of slag and base metal onto said surface. The sealing is made perfect by bringing the rings 18, 21 into tight contact with the throat 1a surface.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention provides a complete seal between the converter mouth and the skirt,
This invention relates to a sealing device between a converter mouth and a skirt, which obtains high-purity exhaust gas (Co gas).

(Prior art and its problems) The outline of the converter exhaust gas treatment device will be explained with reference to FIG.

Hot metal produced in a blast furnace is charged into a converter 1, and pure oxygen is blown into it from an oxygen injection lance 11 to refine it (hereinafter referred to as blowing). In this blowing, oxygen blown from the lance 11 reacts with carbon in the hot metal in the converter 1, and a large amount of high-temperature Co gas is generated. This Co gas is not only extremely dangerous as it will cause carbon monoxide poisoning if it leaks outside, but it also reacts with oxygen in the outside air and combusts rapidly. A skirt 2 that can be raised and lowered is provided to prevent CO gas from leaking out and outside air from entering into the skirt 2.

The high-temperature CO gas generated in the converter 1 is sucked into the skirt 2 by an induced blower 7, cooled by a hood 3 and cooler 4, and removed by dust removers 5 and 6, resulting in a high CO concentration. Gas holder 1 uses only waste as a valuable gas
It is recovered to 0. By switching the damper 9, the gas with a low CO concentration at the beginning and end of the blowing is dissipated through the chimney 8 into the combustion flame at the top.

In this converter exhaust gas treatment device, converter operation is performed in the following three steps. In other words, there is a receiving process in which hot metal produced in a blast furnace is charged into the converter 1, a refining process in which pure oxygen is injected into the hot metal in the converter 1 to refine it, and a tapping process in which the refined steel is taken out. It is done in three steps.

Among these three processes, the pig iron receiving process and the tapping process are performed by tilting the converter 1, so the skirt 2 is raised, and in the refining process, the skirt 2 is lowered, and the opening of the converter 1 and the skirt 2 are moved up. This prevents CO gas from leaking out and outside air from entering.

In this way, the skirt 2 rises during the pig iron receiving and tapping processes,
It has two functions: to enable the converter 1 to tilt, and to lower during the refining process to close off the furnace opening.

By the way, the conventional skirt 2 was constructed as shown in FIG. The figure shows the closed state, and the seal between the skirt 2 and the hood 6 is created by immersing the tip of the seal cylinder 14 in water filled in the water envelope 16, and suspending it by the cross member 15, and then attaching the skirt 2 to the pin. The skirt 2 is water-sealed so as to be movable up and down by a cylinder 12 connected by a cylinder 16.

On the other hand, the seal between the skirt 2 and the furnace opening of the converter 1 is achieved by widening the lower end of the skirt 2 to match the shape of the furnace opening, and sealing is achieved by surface contact between the two.

However, during refining, slag and base metal come out and adhere to the furnace opening 1a of the converter 1, and the surface of the furnace opening 1a becomes uneven, resulting in incomplete surface contact between the skirt 2 and the furnace opening 1a. Therefore, in reality, a gap H exists as shown in the figure. Therefore, CO gas leaked to the outside from this gap H, or outside air was sucked into the hood 6, resulting in a decrease in the amount or quality of the recovered gas.

In addition, recently, there has been an increasing demand for high-purity CO gas recovery, and for this reason there is a trend to operate the hood 3 at a pressure higher than atmospheric pressure to limit the intrusion of outside air as much as possible, creating a new problem in the furnace. Techniques to create a perfect seal between the mouth and the skirt are now required.

(Object of the Invention) The present invention has been made in view of the above circumstances, and provides a furnace which prevents slag and base metal from adhering to the furnace opening and completely seals the furnace opening and the skirt. The purpose is to provide a sealing device between the mouth and the skirt.

(Structure of the Invention) One of the INs made of a seal between the furnace mouth and the skirt of the present invention is a heat-resistant cast iron molded in a hollow cylindrical cross-section having sufficient strength for pressing force and high heat at the lower end of the skirt. A seal ring is provided, a number of jet nozzles are provided that communicate with the hollow part of the seal ring and jet the refrigerant toward the furnace mouth, and the refrigerant is supplied to the hollow part of the seal ring and the refrigerant is jetted from the jet nozzles. The furnace mouth is cooled, and this cooling prevents the adhesion of slag and metal, and the seal ring is completely sealed to the furnace mouth surface.

Another sealing device between the furnace mouth and the skirt of the present invention is
As the cooling method for the furnace mouth mentioned above, a furnace mouth cooling ring is provided near the seal ring, a large number of refrigerant jet nozzles are provided on this furnace mouth cooling ring, and the refrigerant is supplied to the furnace mouth cooling ring so that the jet nozzles A refrigerant is ejected to cool the furnace mouth, thereby preventing the adhesion of slag and metal, and the seal ring is completely sealed to the furnace mouth.

(Example) An example of the sealing device between the furnace mouth and the skirt of the present invention will be described with reference to the drawings. Figures 1 to 6 show a sealing device in which a refrigerant jet nozzle is provided directly on the seal ring. In Figure 1, 1 is a converter, 2 is a skirt, and this skirt 2 is a ring-shaped It is supported by a support beam 17 and can be raised and lowered by a cylinder 12 connected to the support beam 17. A seal ring 18 is located on the outer periphery of the lower end of the skirt 2 and is attached to the lower surface of the support beam 17. Reference numeral 19 denotes a refrigerant jet nozzle provided in communication with the hollow 20 of the seal ring 1B. Reference numeral 21 denotes an outer seal ring provided outside the seal ring 18, which is made of a thin-walled, side-heated, corrosion-resistant steel pipe in an annular shape. It has become. A cylinder 22 is suspended from the support beam 17, and is configured to raise and lower the outer seal ring 21 independently. 23 is a bellows for sealing between the outer seal ring 21 and the seal ring 1B. 2
4 is a collecting pipe for the refrigerant ejected from the refrigerant jetting nozzle 19 toward the furnace mouth 1a, and 25 is a refrigerant discharge pipe connected to this collecting pipe 24.

In the embodiment shown in FIG. 2, an outer seal ring 26 made of a refractory material is provided in place of the outer 11i11 seal ring 21 in FIG.
Since the configuration is the same as that shown in the figure, the explanation will be omitted.

In the embodiment of FIG. 6, on the outside 1111 of the seal ring 18,
A chain ring 27 is installed vertically, and this chain ring 27 and seal ring 1
8 for double sealing. In this case, the refrigerant ejected from the refrigerant ejection nozzle 19 flows down on the surface of the furnace mouth 1a and is not collected.

In each of the embodiments shown in FIGS. 4 to 6, a furnace mouth cooling ring 28 is provided near the seal ring 1B, and a refrigerant jet nozzle 2
The refrigerant is ejected from 9 toward the furnace mouth 1a, and the other parts are as shown in Fig. 1 in Fig. 4 and Fig. 2 in Fig. 5.
This figure and FIG. 6 have the same configuration as FIG. 6, so the explanation will be omitted.

Next, the operation of each embodiment of the seal device between the furnace mouth and the skirt constructed as described above will be explained.

To explain the sealing device shown in FIG. 1, during the refining process, the skirt 2 is lowered by the cylinder 12, and the seal ring 18 comes into contact with the surface of the furnace opening 1a. At this time, the skirt 2 descends while the refrigerant jet nozzle 19 also jets refrigerant, so that the furnace mouth is cooled. Next, the outer seal ring 21 is lowered by the cylinder 22 and comes into contact with the surface of the furnace opening 1a. At this point, the refrigerant is blocked by the outer seal ring 21 and kept at a constant level by the discharge pipe 25 to cool the furnace mouth 1a.

In the case of the sealing device shown in FIG. 2, the same operation as shown in FIG. 1 is performed.

In the case of the seal device shown in FIG. 6, the refrigerant injected from the refrigerant jet nozzle 19 is dammed up to some extent by the chain nozzle 27, and the chain nozzle 27 and the furnace opening 1a are cooled by the refrigerant.

In this way, by spouting the refrigerant from the refrigerant jetting nozzle 19 provided on the seal ring 18, the seal ring 18 is cooled and the furnace port 1a is also cooled, so that the bath is discharged onto the surface of the furnace port 1a. High-temperature slag and metal are rapidly cooled and destroyed by thermal shock. The slag and base metal that are destroyed and made brittle by this thermal shock are crushed by the seal ring 18 by the gravity of the members constituting the cylinder 12 or the skirt 2. This crushing occurs because the flat surface of the furnace mouth 1a and the seal ring 1B have a circular cross-sectional shape, so there is a line contact between the two, so the crushing force is large, and the slag and metal are completely destroyed and the seal ring 1B faces the furnace mouth 1a. and the seal ring 18 are completely brought into close contact and sealed.

In the sealing devices shown in FIGS. 4 to 6, the seal ring 18 connects the refrigerant flowing through the hollow 20 with the furnace mouth cooling ring 2.
It is cooled by the refrigerant ejected from the ejection nozzle 29 provided at B, and at the same time, the furnace opening 1a is also cooled.

As a result of this cooling, the high-temperature slag and metal that have come out on the surface of the furnace mouth 1a are rapidly cooled, embrittled and destroyed by thermal shock, and are further crushed by the seal ring 18, resulting in a seal between the furnace mouth 1a and the base metal. Ring 18 is completely fitted and sealed.

(Effects of the Invention) As detailed above, the sealing device between the furnace mouth and the skirt of the present invention includes a seal ring provided at the lower end of the skirt, and a jet nozzle that jets refrigerant toward the furnace mouth provided on this seal ring. This allows the seal ring and the furnace mouth to be cooled, making the slag and metal embrittled and destroyed by thermal shock. Furthermore, the slag and metal can be easily crushed by the seal ring, and the seal ring is tightly attached to the furnace mouth. This allows for a complete seal between the two.

Similarly, a furnace mouth cooling ring with a refrigerant jet nozzle is provided near the seal ring to cool the seal ring and furnace mouth at the same time, which prevents slag and metal from becoming brittle and destroyed by thermal shock. This can be easily crushed by the seal ring, and the seal ring can be brought into close contact with the furnace mouth to completely seal the two.

Since the seal between the furnace mouth and the skirt can be completely sealed in this way, it is possible to completely prevent the intrusion of outside air, which has the excellent effect of allowing highly pure CO gas to be recovered.

[Brief explanation of the drawing]

Figures 1 to 6 show embodiments of the sealing device between the furnace mouth and skirt of the present invention, and Figures 1 to 6 are longitudinal sectional views of the sealing device in which the seal ring itself is provided with refrigerant injection nozzles. , Figures 4 to 6 are vertical sectional views of a sealing device in which a cooling ring is separately provided to cool the seal ring and the furnace mouth, and Figure 7 is a schematic diagram showing the entire converter exhaust gas treatment device. 8 are vertical sectional views showing a conventional skirt and a furnace opening. 1... Converter 2... Skirt 18... Seal ring 19... Refrigerant jetting nozzle 28... Furnace cooling ring 29... Refrigerant jetting nozzle

Claims (1)

[Claims] 1) A seal ring made of heat-resistant cast iron and provided at the lower end of the skirt and having a hollow cylindrical cross section, which communicates with the hollow part of the seal ring and spouts refrigerant toward the furnace mouth surface. A converter exhaust gas treatment device comprising a nozzle, supplying refrigerant to a hollow part of a seal ring, ejecting the refrigerant from the jet nozzle, and sealing the seal ring in close contact with the furnace mouth surface. Sealing device between converter mouth and skirt. 2) A furnace mouth that has a seal ring made of heat-resistant cast iron that is installed at the lower end of the skirt and has a hollow cylindrical cross section, and a number of jet nozzles that are installed near the seal ring and that jet out refrigerant toward the furnace mouth surface. A converter exhaust gas comprising: a cooling ring, a refrigerant is supplied to the furnace mouth cooling ring, the refrigerant is ejected from a jet nozzle, and a seal ring is brought into close contact with the furnace mouth surface for sealing. A sealing device between the converter mouth and skirt of processing equipment.