JPS6220257B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a device for sealing a lance hole, and more particularly, to a lance hole sealing device that achieves more complete sealing and obtains high-purity exhaust gas.

The outline of the converter exhaust gas treatment apparatus will be explained below 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 (hereinafter referred to as blowing) to refine it.

In this blowing, the oxygen blown from the lance 11 reacts with the carbon in the hot metal in the converter 1,
A large amount of high temperature CO gas is generated.

This CO gas is not only extremely dangerous as it can cause carbon monoxide poisoning if it leaks outside.
There is also the danger of rapid combustion due to reaction with outside air.

Therefore, a skirt 2 that can be raised and lowered is provided between the converter mouth and the hood 3 to prevent CO gas from leaking to the outside and to prevent outside air from entering into the skirt 2.

The CO gas sucked into the skirt 2 by the suction blower 7 in this way is cooled by the hood 3 and cooler 4, removed by dust removers 5 and 6, and sent to the gas holder 10 as a valuable gas. It will be collected.

In addition, the exhaust gas with low CO concentration at the beginning and end of blowing is
By switching the damper 9, only the exhaust gas having a high CO concentration, which is combusted at the top through the chimney 8 and released into the atmosphere, is collected into the gas holder.

In this exhaust gas treatment device, in addition to the skirt portion, CO gas leaks outside or outside air enters the hood from the portion where the lance is inserted and removed, so sealing this portion is also important.

The conventional lance hole sealing device described above has a second
It was configured as shown in the figure.

In the figure, the top of the lance hole 17 is formed into a funnel shape, a seal box 14 is formed in the funnel-shaped hole, and the lance cone 12 is provided to fit into the seal box.

Note that 13 is a labyrinth seal provided at the insertion portion of the lance 11, and 16 is a labyrinth seal for the contact surface between the seal box 14 and the lance cone 12.

Further, when the lance 11 is pulled out, the lance cone 12 is separated at the contact surface with the seal box 14 and lifted together with the lance 11, so that the lance 11 is pulled out along the inside of the lance hole 17.

Meanwhile, inert gas for sealing (e.g. _N2 gas)
First, as shown by arrow A from the supply pipe 15, seal box 1 is
4 and flows out as shown by arrow B to form a curtain seal between the lance cone 12 and the seal box 14. Next, this seal gas flows out to the labyrinth seal 13 as shown by arrow C, and the space between the lance 11 and the lance cone 12 is sealed by the outflow pressure of the seal gas.

In addition, the pressure inside the hood 3 is adjusted by the suction power damper of the suction blower 7 (see Figure 1) to prevent CO gas from leaking outside from the skirt 2 and lance hole 17. The pressure was kept low by 20 minutes, and outside air was sucked in within the explosion limit.

In this way, leakage of CO gas to the outside poses a direct risk of carbon monoxide poisoning, so this was considered first, and lowering the CO concentration was sacrificed.

However, in recent years, there has been an increasing demand for highly purified CO gas to limit the intrusion of outside air as much as possible, and as a result, there has been a trend to operate the hood at a pressure higher than atmospheric pressure, creating a new problem. There is a growing demand for technological development to completely perform these seals.

Therefore, when the conventional lance seal device is used as is and the pressure inside the hood 3 is made to be above atmospheric pressure, the flow of the conventional sealing gas is partially supplied to the sealing box 14, and this supplied sealing gas is , the pressure is reduced in the process of passing through the arrow B and entering the lance cone 12, and this reduced pressure flows out from the arrow C and reaches the labyrinth seal 13, so that there is no pressure between the lance 11 and the lance cone 12. The disadvantage is that the sealing force of the hood 3 is weakened, and a sufficient seal against the pressure inside the hood 3 cannot be obtained.

The present invention aims to solve the above-mentioned conventional drawbacks and provide a sealing device for a lance hole that has a sufficient sealing effect even when the pressure inside the hood exceeds atmospheric pressure.

That is, the present invention is designed to supply sealing gas directly to the labyrinth seal part that seals the insertion part of the lance and the contact surface between the lance hole and the lance cone, and the sealing box is integrated on the upper surface of the lance cone. A seal gas supply pipe is provided so as to communicate with the seal box and the lance cone, and an ejection hole is provided for ejecting seal gas downward from the lance insertion hole of the seal box, and a labyrinth seal of the lance cone is provided. Seal gas ejection holes are also provided on the joint surface with the lance hole and the lance hole.
The sealing gas is ejected directly from these ejection holes, and furthermore, the sealing gas is ejected from two locations to the lance insertion hole, thereby further enhancing the sealing effect.

Furthermore, a retractable sealing member is provided whose lower end is fixed to the sealing box of the sealing device and whose upper end is fixed to the lance, and the lance insertion hole is sealed with a double seal of the sealing gas and the sealing member. It is characterized by what it did.

Examples of the present invention will be described in detail below. In FIG. 3, 17 is a lance hole, the upper part of which is formed into a funnel shape. 12
is a lance cone, and its overall shape is such that it fits into the funnel part of the lance hole 17, and a labyrinth seal 13 is formed in the insertion part of the lance 11. 19 is a seal box integrally provided on the upper surface of the lance cone 12. Reference numeral 15 denotes an inert gas (seal gas) supply pipe, which is directly connected to the seal box 19 and the lance cone 12. Reference numeral 20 denotes an ejection hole provided downward in the lance insertion hole of the seal box 19. 16 is a labyrinth seal provided on the contact surface between the lance cone 12 and the lance hole 17.

FIG. 4 shows another embodiment. In this embodiment, in addition to the embodiment shown in FIG. 3, a retractable sealing member is provided in order to more reliably seal the lance hole. Since the other parts are the same as those in FIG. 3, the explanation here will be omitted.

In the figure, 18 is a retractable sealing member, the lower end of which is fixed to the upper surface of the sealing box 19, while the upper end is connected to the lance 1 through the flange 21.
It is fixed at 1.

The operation of this embodiment configured as above will be explained below. In Figure 3, lance cone 1
2 is separated at the contact surface with the lance hole 17, and can be removed when the lance 11 is extracted.

Now, when the pressure inside the hood 3 is made higher than atmospheric pressure, that pressure also extends into the lance hole 17. Due to this pressure, converter 1 (see Figure 1)
The CO gas generated inside leaks from the labyrinth 13 and the funnel-shaped contact surface between the lance hole 17 and the lance cone 12.

In this state, the inert gas supplied from the inert gas supply pipe 15 in the direction of arrow A is stored in the seal box 19 and lance hole 12 as a high-pressure seal gas. In the case of the seal box 19, the inert gas supplied in this way is
It is ejected downward from 0 in the direction of arrow G,
On the other hand, the lance cone 12 is ejected from the arrow F toward the labyrinth seal 13 and from the arrow E toward the contact surface with the lance hole 17.

Regarding the inert gas ejected from each of the above-mentioned ejection holes, in the case of the labyrinth seal 13, the inert ejected from the arrow F is caused by the curtain of the inert gas ejected from the ejection hole 20 and the sealing effect of the labyrinth 13. It stays in the labyrinth seal 13 as a high-pressure gas and seals with the lance 11. In addition, the inert gas ejected in the direction of arrow E will not flow out if the contact between the lance hole 17 and the lance cone 12 is perfect, but if there is a gap between them due to manufacturing errors or thermal deformation, for example. flows into the gap and seals the gap with a layer of high pressure inert gas.

Further, in the embodiment shown in FIG. 4, the inert gas supplied from the arrow F in the lance cone 12 collides with the surface of the lance 11 and is split up and down, causing the inert gas to be ejected from the ejection hole 20. Flows upward through the curtain. By storing this outflowing inert gas in the sealing member 18, the inside of the sealing member 18 is maintained at a certain pressure, and the balance with this pressure creates a seal and a labyrinth for the inert gas curtain ejected from the ejection hole 20. Seal 13
Completely seal.

As detailed above, according to the lance hole sealing device according to the present invention, the sealing box is integrally provided on the upper surface of the lance cone, and inert gas (sealing gas) is directly supplied to the sealing box and the lance cone. High-pressure inert gas could be ejected from each ejection hole.

In addition, a downward jet hole is provided at the corner of the lance insertion hole of the seal box, and a gas curtain is formed above the labyrinth, so that the inert gas spouted from the lance cone toward the labyrinth is prevented from flowing out. In balance with the internal pressure of the lance hole, the gas remained in the labyrinth seal part as a high-pressure gas layer, and the seal between the lance and the lance cone was completed.

In addition, the sealing of the contact surface between the lance hole and the lance cone is achieved by providing an injection hole only in the lance cone to allow high-pressure inert gas to flow into the gap between the contact surfaces. It became possible to seal as a high-pressure gas layer instead of sealing with a gas curtain, and the sealing could be performed reliably.

In addition, by providing a retractable seal member between the seal box and the lance, the high-pressure gas layer in the labyrinth seal part can be held more reliably, and the sealing performance between the lance and the lance cone can be further improved. did it.

By reliably sealing the lance hole in this way, it is possible to operate with the pressure inside the hood above atmospheric pressure, and high purity CO gas can be recovered, which has excellent industrial effects.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the entire converter exhaust gas treatment apparatus. FIG. 2 is a longitudinal sectional view showing a conventional lance hole sealing device. 3 and 4 show embodiments of the present invention; FIG. 3 is a longitudinal sectional view of a sealing device for a lance hole, and FIG. 4 is a longitudinal sectional view of a sealing device for a lance hole provided with a sealing member. . 1... converter, 12... lance scone, 13...
Labyrinth seal, 15...Inert gas supply pipe,
17... Lance hole, 18... Expandable sealing member, 19... Seal box, 20... Spout hole.

Claims (1)

[Scope of Claims] 1. A lance cone formed in a cone shape so as to fit into a funnel-shaped lance hole with a labyrinth-shaped seal formed on the inner surface of the lance insertion hole;
It consists of a sealing box integrally provided on the upper surface of the lance cone, and an inert gas supply pipe provided in communication with the sealing box and the lance cone, and a sealing box provided downwardly at the corner of the lance insertion hole of the sealing box. An inert gas ejection hole is provided to eject an inert gas towards the lance cone, and an inert gas ejection hole is provided at the joint surface of the labyrinth seal part of the lance cone and the lance hole, and an inert gas jet is provided at the lance insertion part and the joint part of the lance hole. A sealing device for a lance hole of a converter exhaust gas treatment device, which is characterized by being sealed by. 2. A lance cone formed in a cone shape to fit into a funnel-shaped lance hole with a labyrinth-shaped seal formed on the inner surface of the lance insertion hole;
A sealing box integrally provided on the upper surface of the lance cone, a retractable sealing member having a lower end fixed to the upper surface of the sealing box and an upper end fixed to the lance, and a sealing member provided in communication with the sealing box and lance cone. An inert gas supply pipe is provided at the corner of the lance insertion hole of the seal box to eject inert gas downward, while an inert gas is provided at the joint surface of the labyrinth seal and the lance hole of the lance cone. 1. A lance hole sealing device for a converter exhaust gas treatment equipment, characterized in that an active gas blowout hole is provided and a lance insertion portion and a joint portion of the lance hole are sealed with an inert gas.