JPS6220258B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally relates to a lance hole sealing device for furnace equipment using lances, and more particularly to a lance hole sealing device for a converter type coal gasifier.

A molten iron bath type coal gasification furnace blows pulverized coal, oxygen, steam, etc. onto the surface of molten iron in the furnace to generate gas whose main components are carbon monoxide and hydrogen, which can be used for a variety of purposes such as fuel and chemical raw materials. This is a reactor that produces useful gases with . Various types of coal gasification furnaces are known, including converter type, cylindrical horizontal furnace type, etc., but in all of them, the gas produced in the furnace is similar to that in ordinary steelmaking converter furnaces, mixed iron furnaces, etc. A much higher pressure than the generated gas is required. Conventionally, even in converter furnaces used for general steelmaking, the converter gas generated during the steelmaking reaction inside the furnace is a chemically useful gas whose main component is CO gas. A non-combustion method is used for recovery. In the operation of this non-combustion type converter gas recovery equipment, + (positive pressure) or - (negative pressure)
This is controlled to below several tens of millimeters of Ag to suppress as much as possible the blowing of converter gas from the furnace mouth into the atmosphere and the intake of atmospheric air into the furnace. When setting the gas pressure in the hood, if priority is not to reduce the heat capacity of the converter gas, the pressure in the hood is set to the positive pressure side, which prevents gas from blowing out into the atmosphere and contaminates the working environment. If priority is given, it is set to the negative pressure side. Regardless of whether these set pressures are selected on the positive pressure side, negative pressure side, or equal to atmospheric pressure, the pressure of the converter gas will fluctuate as the steelmaking reaction occurs in the converter, so the control can be performed according to the selected purpose. This is not always achieved smoothly, and various control systems have been proposed to overcome this difficulty. Figures 5 and 6 show lance hole seal structures in conventional converter gas generation equipment. In FIG. 5, a sealing hardware 31 is separately provided at the upper end of a lance hole cone 30 provided in a lance hole 7, and a sealing hardware 31 is separately provided to maintain a narrow gap between the labyrinth portion 32 of this sealing hardware and the lance 6, and the lance hole is accessed from the outside. The sealing gas is injected into the labyrinth portion 32 of the metal fitting 31 through the cone 30 and the sealing metal fitting 31 to prevent leakage of gas produced in the furnace. Strictly speaking, it is impossible to seal it tightly because of the gaps, and leakage of converter gas and suction of atmospheric air cannot be completely prevented. FIG. 6 shows a water storage section 33 at the upper end of the lance hole 7.
The lower end of the cover 34, which is hermetically fixed to the outer periphery of the lance, is immersed in the water storage portion 33, and the water storage portion 33 is sealed. This liquid sealing system provides more complete sealing than the structure shown in Figure 5, but on the other hand, if pressure fluctuations greater than the liquid sealing depth occur due to fluctuations in the steelmaking reaction in the converter, the sealing Liquid may be sucked into the furnace or blown out to the surrounding area, resulting in a seal failure. Especially when water is used as the sealing liquid,
If water is sucked into the furnace, there is a risk of a steam explosion, and if water is blown out to the outside air, it may cause burns or other hazards to workers. It may be possible to increase the depth of the liquid seal to prevent seal breakage, but
Increasing the liquid sealing depth has the disadvantage that the length of the lance becomes longer, making the equipment larger and requiring a higher building height.
In addition, the structures shown in Figures 5 and 6 are practically applied to converter operations where the gas pressure inside the furnace is several hundred mmAg or less, and is applied to converter operations where the gas pressure inside the furnace is 10 atm to 50 atm, such as coal gasification operation. It cannot be applied to the generation of high-pressure gas at atmospheric pressure. Since converter-type coal gasifiers are used for high-pressure gas, reliable sealing is especially important at the furnace mouth and lance holes.

The present invention exhibits a sufficient sealing function even for high-pressure generated gas, has excellent heat resistance, and has no risk of seal breakage even during long-term continuous operation, allowing safe and stable gasification operation. An object of the present invention is to provide a lance hole sealing device for a converter type gas generation equipment that is capable of performing the following steps.

The present invention is particularly useful when applied to high-pressure coal gasification operations, but as mentioned above, converter gas recovery is also performed in steelmaking operations, and the present invention is also effective in such cases. Therefore, the converter-type gas generation equipment according to the present invention includes both a general converter equipment for steel manufacturing and a converter-type coal gasifier.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment in which the present invention is applied to a converter type coal gasifier will be described with reference to the drawings.

FIG. 1 is a schematic vertical sectional view showing the overall configuration of a converter type coal gasifier according to the present invention. The tiltable furnace body 1 is lined with refractory bricks on the inside of the iron shell, and a water-cooled fixed hood 3 is arranged above the furnace mouth 1a, which serves as a passage for taking out the produced gas. A furnace mouth seal part 2 that can move up and down is provided between the furnace mouth part 1a and the furnace mouth part 1a. A molten iron bath 4 is formed at the bottom of the furnace body 1, and molten slag 5 floats on the top surface of the bath. A lance hole 7 with a water-cooled structure is similarly formed in the fixed hood 3, and a lance 6 is inserted into the furnace through this lance hole, and pulverized coal, oxygen, and steam are sprayed onto the upper surface of the molten iron bath 4 from the lance tip 6a. Generates gases including CO, _H2 . After passing through the hood 3, this generated gas is sent to a generated gas processing facility (not shown).

In this embodiment, the furnace mouth seal part 2 is the furnace mouth part 1a.
A furnace mouth ring 35 with a water-cooled structure fixed to the furnace mouth ring, a jacket-shaped skirt 36 that can be closely attached to the furnace mouth ring and movable up and down with respect to the fixed hood 3, and a structure between the fixed hood 3 and the skirt 36. and two parts attached to the outside of the skirt with a gap therebetween.
Heavy tubular first skirt expansion 37
and a double cylindrical second tube on the lower surface of the outer diameter side of the skirt.
a furnace mouth sealing jacket 39 attached via a skirt expansion 38 and pressed against the upper surface of the outer diameter side of the furnace mouth ring; and a skirt lifting cylinder 40 for moving the skirt up and down.
a jacket lifting cylinder 41 for vertically moving the furnace mouth sealing jacket 39 relative to the skirt; and a cylindrical shielding plate 42 disposed between the skirt 36 and the first skirt expansion 37. An annular gap between the first and second skirt expansions 37 and 38 is filled with cooling water, and dust washing water is provided between the skirt 36 and the first skirt expansion 37. When the furnace body 1 is tilted or when inspecting the inside of the furnace, the skirt 36 is pulled up by the skirt lifting cylinder 40, and during furnace operation, the skirt 36 and the furnace are raised by the cylinders 40 and 41. The mouth sealing jackets 39 are each pressed against the furnace mouth ring 35 for sealing.
The first and second double skirt expansions are flexible and made of thin metal sheets so that they can be used in high-temperature environments. It exhibits a reliable furnace mouth sealing function against gas. Note that 43 is an annular tube provided at the upper end of the skirt for spraying water between the fixed hood 3 and the inner circumference of the skirt 36.

Next, the lance hole sealing device in this embodiment will be explained in detail with reference to FIGS. 2 to 4.

2 to 4 are all enlarged longitudinal sectional views of the lance hole sealing portion 27 shown in FIG. 1. The lance 6 is a water-cooled multi-tube, and in FIG. 2, the lance is pulled up and the tip of the lance touches the upper flange 14 of the lance hole expansion, which will be described later.
It is not shown because it is located at a higher position than the free height f of the upper surface. The lower flange 20 of the water supply and drainage jacket 18 is joined to the lance hole upper flange 21 on the upper surface of the lance hole 7 with bolts or the like. The water supply and drainage jacket 18 is provided with one or more water supply pipes 24 on its side for supplying water.
The double cylindrical lance hole expansion has an inner circumference side expansion 15 and an outer circumference side expansion 16 concentrically combined, and has an upper annular flange 14 and a lower annular flange 17 at their upper and lower ends, respectively. It is constructed by being fixed by welding or the like. The lower annular flange 17 of this double cylindrical lance hole expansion is joined to the upper flange 19 of the water supply and drainage jacket 18 by bolts or the like. Inner and outer expansion 1
The annular (cylindrical) gap between 5 and 16 is closed by the upper annular flange 14, but the lower annular flange 17 and the upper flange 19 of the water supply and drainage jacket 18 are open as shown. The cooling water introduced from the water supply pipe 24 is connected to the jacket 1.
8 and the double cylindrical lance hole expansion. The water supply and drainage jacket 18 is also provided with one or more drainage branch pipes 23. One end 23a of each drainage branch pipe 23 extends into the double cylindrical lance hole expansion, and the other end is connected to the drainage annular pipe 22 around the lance hole, thus connecting the double cylindrical lance hole expansion. The cooling water in the lance hole expansion is drained from one end 23a of the drain branch pipe 23 through the branch pipe 23 and the drain annular pipe 22.

Referring to FIGS. 3 and 4, the lance 6 includes a lance outer cylinder 8, a lance partition cylinder 9, and a lance inner cylinder group 1.
0 are assembled concentrically, and the inside of the lance inner cylinder group 10 is further formed into multiple pipes, through which pulverized coal, oxygen, water vapor, etc. pass. Lance outer cylinder 8
Cooling water is configured to flow between the inside of the lance partition tube 9 and the lance partition tube 9, and between the inside of the lance partition tube 9 and the lance inner tube group 10, respectively. Lance outer cylinder 8
An outer flange 11 communicating with the lance outer cylinder 8 is formed on the outer periphery of the lance outer cylinder 8 . A water flow adjusting rib 25 is formed on the outer periphery of the lance partition tube 9 at a position corresponding to the tube flange. A lance hole sealing seat 12 is attached to the lower surface of the outer cylinder flange 11, and an elastic packing 13 is embedded in a groove on the lower surface of the sealing seat 12. The lance 6 is inserted into the double cylindrical lance hole expansion from above, and at this time, the elastic packing 13 of the sealing seat 12 is inserted into the upper annular flange 1 of the lance hole expansion.
4 and performs a sealing function for the lance hole.

FIG. 3 shows a state in which the lance tip 6a is at the height of the blowing upper limit point a in FIG. , the elastic packing 13 presses against the upper annular flange 1 with a constant pressing force.
I'm pushing 4. A space 26 between the lance outer cylinder 8 and the inner expansion 15 is connected to the inside of the fixed hood 3 shown in FIG. Now, in order to prevent the generated gas in the space 26 from leaking into the atmosphere, the upper annular flange 14 is connected to the second
It is pushed down by the minimum compression stroke g to a in FIG. 3 from the height of the expansion free length f in the figure. The material of the lance hole expansion is also made of a heat-resistant thin metal plate, similar to the skirt expansion. When the lance is pushed down to the position shown in Figure 3, the contact pressure between the elastic packing 13 and the upper annular flange 14 based on the spring reaction forces of the inner expansion 15 and the outer expansion 16 prevents gas leakage. The spring constant and stroke g of the expansion are set to be greater than or equal to what is required. In the illustrated embodiment, the elastic packing 13 is provided in two layers, but the sealing ability can be increased by further layering, and if a labyrinth portion or the like is provided further inside the inner elastic packing, the heat resistance can be improved. Improves sex. The contact pressure between the elastic packing 13 and the upper annular flange 14 is not only due to the spring reaction force of the expansion, but also due to an increase in the contact pressure when the pressure of the cooling water filled in the expansion is high. Contribute to

FIG. 4 shows a state in which the lance tip 6a is at the lower blowing limit point b in FIG. 1, and the upper surface of the upper annular flange 14 is pushed down to the height b in FIG. 4. The position is a stroke c below the height a in Fig. 3, and this height difference c is the same as the adjustment range shown in Fig. 1. During gas generation operation, the lance tip 6a is Between the blowing upper limit point a and the blowing lower limit point b, that is, between the adjustment range c, the furnace condition such as the level and temperature of the molten iron bath 4, the blowing system of pulverized coal, oxygen, steam, etc., and the generated gas condition. The lance height is set according to the states of various control elements such as. Even when the upper annular flange 14 is at the height of the lower blowing limit point b as shown in Fig. 4, the drain branch pipe tip 23a does not come into contact with the upper annular flange 14, and there is sufficient clearance to prevent cooling water from flowing out. The tip position of the drainage branch pipe is determined so that the At the lower limit of blowing, a higher contact pressure is generated between the upper annular flange 14 and the elastic packing 13, resulting in a higher sealing function. Note that position d shown in Fig. 1 is the position of the blowing standby point, and when the furnace body is tilted to observe the situation inside the furnace during operation, the lance tip is pulled up to this position, but the lance tip 6a is When raising the temperature above the blowing upper limit point a, the blowing of pulverized coal, oxygen, etc. is stopped, so no generated gas is generated, and even if the seal between the upper annular flange 14 and the elastic packing 13 does not function, the generated gas will not be generated. No leakage will occur. The elastic packing 13 is caused by the cooling water flowing inside the outer cylinder flange 11 and the cooling water inside the lance hole expansion to seal the sealing seat 12.
and is cooled via the upper annular flange 14.

The effects of the present invention are listed below.

(a) Compared to the incomplete sealing in the labyrinth type seal, the elastic packing 13 and the upper flange 1
Since a complete seal is obtained by the contact force of 4, it is possible to completely prevent pollution of the working environment due to the generated gas blowing out into the atmosphere, or a decrease in the heat capacity of the generated gas due to the suction of the atmosphere.

(b) In addition, there is a danger of steam explosion due to the suction of sealing water into the furnace in liquid seals.
Alternatively, dangers such as burns to workers due to the sealing water and generated gas blowing out into the atmosphere can be completely prevented.

(c) Furthermore, even if the pressure of the generated gas is much higher than in the case of conventional converter gas, the sealing function functions sufficiently, making the lance hole sealing device extremely stable compared to conventional technology. can be realized.

(d) Since the expansion and elastic packing, which are the weakest in terms of heat, are cleaned with forcibly circulated water, stable operation is possible from the standpoint of heat resistance.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical sectional view showing the overall configuration of a converter-type coal gasifier according to the present invention, and FIG. 2 is an enlarged vertical sectional view of the lance hole sealing part of the present invention in a state where the lance is pulled out. Figures 3 and 4 are longitudinal sectional views of the lance hole sealing portion when the lance is in the blowing position, respectively, and Figures 5 and 6 are partial sectional views showing conventional examples of lance hole sealing devices. be. DESCRIPTION OF SYMBOLS 1... Furnace body, 3... Fixed hood, 4... Molten iron bath, 6... Lance, 7... Lance hole, 8... Lance outer cylinder, 11... Outer cylinder flange, 13... Elastic packing, 14... Upper annular flange, 15...
Inner circumference side expansion, 16... Outer circumference side expansion, 18... Water supply and drainage jacket, 22...
...Drainage annular pipe, 23...Drainage branch pipe, 24...Water supply pipe, 25...Water flow adjustment rib.

Claims (1)

[Claims] 1. A jacket-shaped outer cylinder flange portion provided on the lance outer cylinder so as to communicate with the lance outer cylinder at a position above the lance hole, a sealing member provided on the lower surface of the outer cylinder flange portion, and the lance a double cylindrical lance hole expansion attached to the upper part of the hole, the upper end of which is closed by an annular plate, and the annular plate contacts the sealing member of the outer cylinder flange portion; The lance hole expansion is filled with a cooling liquid, and when gas is generated, the annular plate at the upper end of the expansion is pressed by the outer cylinder flange of the lance outer cylinder inserted into the lance hole. Lance hole sealing device for converter type gas generation equipment.