JPH0145517B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a furnace mouth sealing device for a coal gasifier.

As molten iron bath coal gasification furnaces, there are various types known, including a converter type similar to a steelmaking converter, a horizontal cylindrical furnace similar to a mixed iron furnace, and other types. The invention relates to the former converter type quartz gasifier. FIG. 1 shows a schematic structure of a converter type coal gasifier according to the present invention, and its outline will be explained. Above the furnace mouth part 1b of the tiltable furnace body 1,
A hood 21 that serves as a passage for taking out the produced gas is arranged, and this hood (fixed hood) 21 and the furnace mouth part 1b
A movable intermediate hood (skirt) 14 is provided between the two. The furnace body 1 is lined with refractory bricks inside the iron skin of the outer shell, and a molten iron bath is formed at the bottom of the lining. A lance (not shown) is vertically inserted into the furnace through a lance hole 43 formed in the fixed hood 21, and pulverized coal, oxygen, and steam are blown into the furnace through the lance to generate carbon monoxide and hydrogen gas. Take it out. During gas generation, the furnace mouth 1b and the skirt 14 are in close contact with each other, but when introducing molten iron into the furnace body, or when observing the situation inside the furnace, the skirt 14 is pulled up and the furnace body 1 is moved around the horizontal axis. It becomes possible to roll.

The gas produced in such a coal gasification furnace has a wide range of uses, including fuel and chemical raw materials, but in any case, the pressure of the produced gas is the same as that generated in a converter used for ordinary steelmaking. much higher than that required. For example, city gas has a pressure of about 10 atm, and gas for combined power generation has a pressure of about 14 to 18 atm.
For methanol synthesis gas, a gas pressure of 50 to 100 atmospheres is required. In the above converter type coal gasifier
Although it is structurally difficult to obtain a generated gas of 10 atm or more, it is still much higher than the gas pressure near the furnace mouth of a steelmaking converter, which is at most ± several tens of millimeters of Ag. It will be done. If the pressure of the produced gas generated in a coal gasification furnace is lower than the pressure required for each application, the pressure must be increased using a compressor, but the energy cost for boosting pressure can be kept low and reactions within the furnace can be promoted. In order to
It is desirable to make the pressure generated in the coal gasifier as high as possible. In addition, the inside of the coal gasification furnace is
Reliable and safe operation not only against the pressures mentioned above, but also against the high temperature and spitting of the produced gas, molten steel droplets and slag droplets scattered along with the produced gas flow, and even columnar vibrations of the produced gas. There has to be something you can do.

Various structures have been proposed for sealing between the furnace mouth and the intermediate hood and fixed hood, and one conventional example is shown in FIG. Intermediate hood 5 disposed between furnace mouth portion 1b and fixed hood 50
1, an elevating hood 52 is attached to an elevating cylinder 53.
It is suspended from the fixed hood 50 via the
A single main bellows 54 and a single sub-bellows 55 are installed between the fixed hood 50 and the intermediate hood 51 and between the intermediate hood 51 and the elevating hood 52, respectively. The furnace mouthpiece 56 at the upper end of the furnace mouth and the intermediate hood 51 and the furnace mouthpiece 51 and the lifting hood 52 are in surface contact with each other, and in some cases, a gasket 57 is provided on the contact surface of the furnace mouthpiece. This prevents gas leakage during furnace operation. When the furnace body is rolling, the intermediate hood 51 moves up and down through the lifting cylinder 53.
By the operation of , it is lifted up by the elevating hood 52 and ascends.

In this conventional example, as described above, since the main bellows 54 and the sub-bellows 55 are each only one layer, molten steel droplets and slag droplets are deposited in the gap between the fixed hood 50 and the intermediate hood 51 and between the furnace mouth fittings 56 and the intermediate hood 51.
If the gas leaks to the outside of the intermediate hood through the gap, there is a danger that the main bellows and sub-bellows will melt and open a hole, causing gas to blow out into the outside air, destroying the surrounding environment, and possibly causing a fire accident. . Originally, this type of bellows is made of a thin film made of rubber, plastic, or metal, so it is susceptible to hot metal droplets and slag droplets, and is susceptible to holes.

Furthermore, in the above embodiment, the exhaust gas is pressurized and filled to prevent infiltration of furnace gas, steam, etc. into the area surrounded by the fixed hood 50, intermediate hood 51, and main bellows 54. food 5
The energy of the gas ejected from the 0.51 gap can be used to prevent metal and slag from being blown away along with the gas in the furnace or as a splash. It is difficult because it is large.

In addition, under conditions where metal particles and slag droplets are scattered due to such a splash, it is difficult to expect the primary seal to be complete, and the gasket 57 on the furnace mouth metal fittings is difficult to expect.
The secondary sealing part of the lifting hood 52 is easily damaged because the gasket 57 faces upward, and the lower surface of the lifting hood 52 may also be damaged by flying metal or slag, and there is a risk of the secondary sealing breaking. There is. Particularly with this structure, if it is damaged, it is impossible to replace only that part and repair work will be extensive.

Furthermore, in the above structure, both the elevating hood and the intermediate hood are raised and lowered only by the elevating cylinder 53, and the contact surface between these hoods and the furnace mouthpiece is horizontal, and the degree of contact on this surface is not very strong, and at most This is about the weight of the intermediate hood and the spring reaction force of the main bellows. For these reasons, when gas column vibration occurs in the exhaust gas hood during operation, the intermediate hood tends to move against the furnace mouth fittings.

As described above, conventional converter-type coal gasifiers have not yet been satisfactory in terms of high-pressure operation, safe operation, etc.

The present invention can withstand high-temperature, high-pressure generated gas, and can safely and reliably seal the gas without causing any adverse effects due to the adhesion of molten steel droplets, slag droplets, or air column vibration, and can also be repaired. It is an object of the present invention to provide a furnace mouth sealing device for a converter type coal gasifier that can be easily constructed.

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 2 and 3 are longitudinal cross-sectional views at the furnace mouth of a converter-type coal gasifier according to an embodiment of the present invention. In particular, FIG. 2 is a detailed enlarged view of section A in FIG. 1, and shows the state during gasification operation. Moreover, FIG. 3 is a diagram with the skirt raised compared to FIG. 2. However, in these figures, the lance inserted into the center of the furnace mouth is not shown. X- in the diagram
The X-ray represents the center line of the furnace body 1. A furnace mouth ring 2 made of a cast product is fixed to the upper end of the furnace mouth portion 1b. In this case, an O-ring 4a or the like is provided on the furnace mouth flange 1a of the furnace mouth portion 1b to prevent the produced gas from leaking through the lower surface of the furnace mouth ring 2.

The inner diameter side of the upper surface of the furnace mouth ring 2 forms a dish-shaped tapered surface 2a (Fig. 3) that slopes downward toward the center of the furnace mouth, and the outer diameter side of the upper surface is a recessed stepped surface. O-ring 4b in the groove formed on the surface
is installed. A furnace mouth liner 5 is replaceably attached to the stepped surface using countersunk bolts or the like. A cooling water pipe 3 is cast into the inside of the furnace mouth ring 2, which cools the inside and prevents metal and slag from adhering to the ring surface.

On the upper side of the furnace mouth ring 2, a jacket-shaped skirt (movable hood) 14 having a tapered lower surface that is in close contact with the dish-shaped tapered surface of the ring 2 is provided. It is suspended via a skirt lifting cylinder 17. A packing jacket 8 is attached to the lower surface of the outer diameter side of the skirt 14 via a double cylindrical seal expansion consisting of an outer seal expansion 12 and an inner seal expansion 13.
can be installed. The jacket 8 for the jacket communicates with the inside of the jacket-shaped skirt 14 through the double cylindrical seal expansion,
Further, a packing seat 7 having a sealing packing 6 is attached to the lower surface of the jacket 8.
Further, between the skirt 14 and the packing jacket 8, an appropriate number of packing cylinders 10 are attached to the outside thereof, and the operation of the cylinders 10 causes the sealing packing 6 of the packing seat 7 on the lower surface of the packing jacket 8 to be closed. is pressed against the furnace mouth liner 5. The inside of the jacket-shaped skirt 14 and the double cylindrical seal expansion 12,
Cooling water flows inside the jacket 8 through the jacket 13. In addition, this skirt 14
The cooling water in the packing jacket 8 is supplied and drained from an appropriate location on the outside in one pass, or from multiple locations by dividing the interior into a plurality of blocks. The stroke of the seal cylinder 10, the outer seal expansion 12, and the inner seal expansion 13 is the same as that of the seal seal 6.
It is enough to absorb the pressing allowance of the coal gasifier, the thermal expansion allowance of the coal gasifier, and the error in the stop position.

An annular expansion seat 15 is attached to the upper surface of the lower projecting portion of the skirt 14, and is located between the expansion seat 15 and the flange portion 21a of the fixed hood 21, and between the skirt 14
A double cylindrical skirt expansion consisting of an inner circumferential skirt expansion 23 and an outer circumferential skirt expansion 24 is mounted with a certain space between it and the side portions. Here, the double cylindrical seal expansion 12 mentioned above,
13 and the double cylindrical skirt expansions 23 and 24 are arranged concentrically with respect to the center X-X of the furnace mouth, and these materials are made of metal so that they can be used in a high-temperature atmosphere. is preferably adopted.

In order to drip or spray water into the gap 11 between the fixed hood 21 and the inner periphery of the skirt 14, an annular tube 22 with holes in the periphery is provided at the upper end of the skirt.

Inner skirt expansion 23 and outer skirt expansion 2 spaced concentrically
4 has flange plates fixed to its upper and lower ends to constitute an annular expansion cylinder with a closed bottom, of which the lower flange plate 16 is attached to the expansion seat 15 with bolts or the like,
The upper flange plate 18 is attached to the flange portion 21a of the fixed hood 21, and is connected to a water supply pipe 30 and a drain pipe 31, which will be described later.
The water supply pipe 30 and the discharge pipe 31 extend from the annular gap of the annular expansion cylinder through the flange 21a of the fixed hood 21, and the drain pipe 31 is connected to a drainage trough 32. Note 3
0a and 31a are sleeves for supporting the water supply pipe 30 and the drain pipe 31, respectively.

On the lower surface of the flange portion 21a of the fixed hood 21, there is a cylindrical shielding plate 26 that hangs down and extends between the outer side of the fixed hood 21, more precisely, the outer side of the skirt 14 and the inner skirt expansion 23.
is fixed. Preferably, the lower end of the shielding plate 26 is provided with dust cleaning water 25 stored between the skirt 14 and the inner skirt expansion 23.
It is best to soak it in. In consideration of the case where the shield plate 26 is immersed, a pressure equalizing hole 29 is provided at the upper position of the shield plate 26 so that the pressures in the shield plate inner space 27 and the shield plate outer space 28 are equalized.

A cleaning hole 19 is provided that extends across the bottom of the expansion seat 15 to drain the dust cleaning water 25. The cleaning hole 19 is closed with a cleaning hole cover 20 except when cleaning water and dust are extracted and replaced with fresh water, such as during maintenance.

A level detection tube 39 equipped with a level meter 40 is pulled out from the middle of the cleaning hole 19, and thereby the water level of the dust cleaning water 25 is monitored. The level detection tube 39 includes a rotation joint 38, a pressure impulse tube 37, a rotation joint 39, a pressure impulse tube 35, and a rotation joint 3.
4 and the impulse pipe 33 to communicate with the cylindrical shielding plate inner space 27 . A water supply pipe 41 and a water supply valve 42 are provided to replenish water when the water level in the level detection pipe 39 drops.

In the above-described configuration, the generated gas that is about to leak from between the lower surface of the furnace mouth ring 2 and the furnace mouth flange 1a is sealed by the O-ring 4a, and the generated gas is sealed between the upper surface of the furnace mouth ring 2 and the bottom surface of the furnace mouth liner 5. The generated gas that is about to leak from between the gap is sealed with the O-ring 4b, and the upper surface of the furnace mouth liner 5 and the seal seat 7 are sealed.
Since the generated gas that is about to leak from between these parts is sealed by the sealing packing 6, leakage of the generated gas from these parts is prevented. The pressing force of the sealing packing 6 against the furnace mouth liner 5 can be arbitrarily and optimally set by the packing cylinder 10.

Since the upper surface of the furnace mouth ring 2 and the lower surface of the skirt 14 are in contact with each other, it is very difficult for metal droplets and slag droplets to enter from there. Further, since the skirt 14 and the furnace mouth ring 2 are water-cooled, metals, slag, etc. are difficult to weld and are even more difficult to penetrate. Even if a small amount of metal or slag invades the upper surface of the furnace mouth liner 5 and damages the upper surface of the furnace mouth liner 5 or the sealing packing 6, the original function can be restored simply by replacing these parts.

Even if a gap is created between the top surface of the furnace mouth ring 2 and the bottom surface of the skirt 14 due to an emergency or abnormal operation, and metal and slag are scattered and collide with the inner seal expansion 13, water cooling is maintained. The metal and slag cool down quickly and do not damage the seal expansion 13.

Metal and slag that try to enter the space 27 inside the shield plate through the gap between the inside of the skirt 14 and the fixed hood 21 are removed by dripping water continuously or intermittently from the annular pipe 22 in an amount that does not interfere with the operation. The amount of intrusion can be minimized. Furthermore, the metal and slag that have entered the space 27 inside the shielding plate collide with the shielding plate 26 and the dust cleaning water 2
Fall into 5. In this way, metal and dust will not directly collide with and damage the inner skirt expansion 23. Furthermore, since the inner circumferential skirt expansion 23 is water-cooled, there is no problem of damage caused by the heat from the generated gas passing therethrough.

During operation, when the water level of the dust washing water 25 drops by an allowable value from the appropriate level a shown in FIG. 2 due to evaporation or the like, the water supply valve 42 is opened to replenish the water level. Since the pressure in the space 27 inside the shield plate is communicated with the level detection tube 39, it can be measured with the level meter 40 and replenishment operations can be easily performed.

When the skirt 14 is raised by the skirt lifting cylinder 17 during normal operation or in an emergency, the cooling water between the inner skirt expansion 23 and the outer skirt expansion 24 is drained to the drainage trough 32. The water level in the trough rose from the normal level B before rising to the rising level C (Figure 3).
rise to Conversely, when lowering the skirt 14, even if the amount of replenishment from the water supply pipe 30 is insufficient, the cooling water in the drainage trough 32 is temporarily sucked in and the skirt expansion 23, 24 is lowered.
This prevents the internal pressure from becoming negative pressure. Since the lower surface of the skirt 14 firmly presses the upper surface of the furnace mouth ring 2 by the skirt lifting cylinder 17, it is possible to prevent the skirt 14 from vibrating even when the generated gas column vibrates. In particular, in the present invention, the upper surface of the furnace mouth ring that contacts the skirt 14 is a dish-shaped tapered surface, so that misalignment due to vibrations or the like is less likely to occur than in the case of horizontal surface contact.

As described above, the present invention doubles the seal expansion and the skirt expansion, cools them with cooling water, and allows the skirt to closely adhere to the replaceable furnace mouth liner. It is also possible to greatly increase safety against fires caused by slag and abnormal situations. Note that the present invention can also be applied to a general converter for steelmaking.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view of a converter-type coal gasifier according to an embodiment of the present invention, FIG. FIG. 3 is an enlarged vertical sectional view of the furnace mouth with the skirt raised, and FIG. 4 is a partial vertical sectional view of a conventional furnace mouth sealing device. DESCRIPTION OF SYMBOLS 1... Furnace body, 2... Furnace mouth ring, 5... Furnace mouth liner, 6... Seal packing, 8... Jacket for packing, 10... Cylinder for packing,
12...Outer seal expansion, 13...
...Inner peripheral side seal expansion, 14...Skirt, 17...Skirt lifting cylinder, 21...
Fixed hood, 23... Inner skirt expansion, 24... Outer skirt expansion, 25... Dust washing water, 26... Shielding plate,
30... Water supply pipe, 31... Drain pipe, 33, 35,
37... Impulse tube, 39... Level detection tube, 40...
Level meter, 43...Lance hole.

Claims (1)

[Claims] 1. A furnace mouth ring which is fixed to the upper end of the furnace mouth part, has a dish-shaped tapered surface on its inner diameter side upper surface, and has a furnace mouth liner attached to its outer diameter side upper surface in a replaceable manner;
A jacket-shaped skirt whose inside is filled with liquid and which is suspended from a fixed hood by a skirt elevating cylinder and which can be brought into pressure contact with the tapered surface of the furnace mouth ring, and the skirt through a double seal expansion inside and outside. a packing jacket which is attached in communication with the lower part of the belt and which can be pressed against the furnace mouth liner of the furnace mouth ring via a packing member by a packing cylinder, and which is installed between the fixed hood and the skirt and inside the a double skirt expansion, inside and outside, through which liquid flows; and a cylindrical shape that is suspended from the fixed hood and immersed in the dust cleaning liquid introduced between the skirt expansion and the skirt, the lower end of which is inside. 1. A furnace mouth sealing device for a coal gasifier, comprising a shielding plate.