JPH0212273B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for repairing a damaged part of a coke oven gas duct by press-fitting a low-moisture paste mortar into the damaged part.

In the case of an underjet type coke oven, the heating gas in the coke oven is supplied from the main furnace through a distribution branch pipe, a tuyere pipe, and a gas duct made of refractory bricks to each heating chamber. The temperature inside this gas duct is normally 150 to 1200℃, but due to the furnace fuel gas being switched and supplied every 15 to 25 minutes, the temperature constantly changes by 100 to 300℃, causing damage due to spalling, etc., and causing gas leaks. Cause. Fuel gas leakage from the gas duct results in insufficient gas supply to the combustion chamber, disturbs the temperature distribution in the oven length direction, delays the carbonization time of the coke oven, and causes damage to the coke oven body.

Conventionally, the method of repairing this gas duct was to remove moisture.
Generally, a method is adopted in which about 50% of the mortar is pushed up into the gas duct. According to Figure 1,
Let me explain this. In the figure, 1 is a gas distribution branch pipe, 2 is a tuyere pipe, 3 is a gas duct, 4 is a combustion chamber, 5 is a mortar tank, 6 is a compressed air pipe, 7 is a mortar transport pipe, 8 is a tuyere pipe insertion fitting, 9 is a compressed air kettle,
10 is a mortar pot, 11 is a heat storage chamber, 12 is an air hole, and 13 is a floor plate. For repairs, pour mortar with a moisture content of approximately 50% into the mortar tank 5, remove the plug from the tuyere pipe 2, and insert the tuyere pipe insertion fitting 8.
Attach the compressed air container 9 and open the mortar container 10. The mortar is pushed up into the gas duct 3 by air pressure and is filled into the duct joints and damaged parts. The height at which the mortar is pushed up is determined by the specific gravity of the mortar and the air pressure, but after a certain period of time, when the air is removed, the mortar returns to the mortar tank 5 by its own weight.

In the case of the repair method described above, the mortar to be injected has a high moisture content, which causes the gas duct refractory bricks to cool down rapidly, which in turn promotes damage to the duct due to spalling, etc., and makes it difficult to repair large parts of the bricks that have fallen off, about 40 to 50 mm in size. Have difficulty. Furthermore, if the damaged area is particularly large, there is a drawback that the injected mortar may flow into the heat storage chamber 11 or the mortar may be pushed up to the bottom of the combustion chamber 4 due to incorrect air pressure adjustment.

The present inventors have studied a new repair method that does not have the above-mentioned drawbacks, and have completed the present invention.
That is, in the present invention, a mortar discharge port is provided at the tip of a mortar transport pipe, and packing made of a heat-resistant material having approximately the same diameter as the gas duct is placed before and after the discharge port so as to form a mortar compression chamber together with the inner wall of the gas duct. A method and apparatus for repairing a coke oven gas duct, characterized in that mortar is press-filled into a damaged part of the coke oven gas duct using an attached repair device.

The repair device of the present invention will be explained based on FIG. In the figure, 3 is a mortar transport pipe, 4 is a discharge port, 5 is a packing, and 6 is a flexible connecting pipe. Packings are attached to the front, rear, and tip of the discharge port, and are approximately the same size as the diameter of the gas duct, and are made of a heat-resistant material. The packing before and after the discharge port forms a mortar compression chamber together with the inner wall of the gas duct. In order to prevent the packing from being burnt out, it is more preferable to apply mortar to both sides of the packing. There is no particular restriction on the number of packing sheets, but it is preferable that the number of packing sheets is at least two or more in each case. The packings other than the packing attached to the part closest to the discharge port and forming the mortar compression chamber retain the mortar leaking from the compression chamber, and also perform the function of cleaning the mortar that has adhered when the mortar is pulled out. It is preferable to use a flexible heat-resistant connecting pipe in order to quickly insert and withdraw the discharge equipment into the gas duct.

An embodiment of the repair method of the present invention will be described based on FIG. 2. In the figure, 1 is a mortar pressure pump, 2
is a popper for mortar, 3 is a mortar transport pipe, 4
5 is a mortar discharge port, 5 is a packing, 6 is a flexible connecting pipe, 7 is a heat storage chamber, 8 is a combustion chamber, and 9 is an air hole. Next, the repair methods are listed in order as follows.

(1) Prior to repairing the duct, use a heat-resistant fiberscope, etc. to investigate the damaged areas and degree of damage in the duct, and check the amount of mortar discharge, the position of the mortar discharge, and the movement speed of the mortar discharge (mortar discharge Determine the time from when the equipment is inserted into the gas duct until it is removed.

(2) Put mortar with a moisture content of about 20% into the mortar popper 2, operate the mortar pressure pump 1, and pump the mortar to be discharged from the mortar outlet 4 outside the duct to the planned quantity. Adjust the rotation speed.

(3) Insert the mortar discharge port 4 into the gas duct to the planned height and operate the pump 1. At this time, since the connecting tube is made of a flexible material, insertion can be done in a short time. The packing 5 is in close contact with the inner wall of the duct, and the space of the packing before and after the mortar discharge port forms one compression chamber, and the structure is such that the discharged mortar can be press-fitted into the damaged part of the gas duct.

(4) Repair mortar weighs 10 to 25 kg/cm ² at the pump outlet.
After passing through the transport pipe and filling the space between the packings before and after the discharge port, it is press-fitted into the damaged part of the duct. Excess mortar enters the spaces before and after the discharge opening space.

(5) After operating the pump according to a predetermined pattern depending on the degree of damage, pull out the transport pipe from inside the gas duct. It can also be pulled out in a short time due to the effect of the flexible connecting pipe.

(6) When pulling out the transport pipe, the packing at the tip serves to clean any excess mortar stuck inside the gas duct.

The mortar used in the repair of the present invention may be kept in a pasty state, but tests have shown that the optimal moisture content of the mortar normally used is 15 to 25 wt%. In other words, a test duct made of firebrick with an inner diameter of 65 mm and a height of 3 m that can be heated to any desired temperature was installed, damaged areas of various sizes were artificially created inside the duct, and a mortar press-in test was conducted, after which the duct was dismantled. The penetration of mortar into the damaged area and the degree of crimping were observed. As a result, the moisture content of the mortar was 15wt.
If it is less than %, moisture dries quickly and mortar does not penetrate sufficiently into joints and cracks. Furthermore, the adhesion is insufficient and the strength is brittle. Pressing in with a mortar pump is also extremely difficult. It has been found that when the moisture content of mortar is approximately 15 to 25 wt%, mortar penetrates well into joints and cracks, and even into the smallest cracks. If it exceeds 25wt%,
This is not preferable because the water content increases accordingly and the drawbacks of the conventional method described above are more likely to occur.

The time the mortar discharge equipment stays in the gas duct naturally varies depending on the diameter of the repaired duct, the degree of damage, and the amount of mortar discharged, but because the inner wall of the duct is at a high temperature, the stay time is limited to a certain range. In the present invention, since a heat-resistant flexible pipe is used as a connecting pipe for the mortar transport pipe, it can be easily inserted and withdrawn, and the residence time can be easily adjusted.

The advantages of the repair method of the present invention are listed below.

(1) Since the moisture content of mortar is low, there is no increase in damage to gas ducts. (2) Since it is not a push-up method, there is no chance of the fuel flowing into the heat storage chamber and pushing up to the bottom of the combustion chamber. (3) Since it is a press-fit filling method, 1
It is possible to repair hair cracks of approximately 1.0 mm in size to broken bricks of 40 to 50 mm or more, which could not be repaired using conventional methods. (4) Maintenance frequency can be significantly reduced compared to conventional methods.

Due to the above-mentioned effects, when the repair method of the present invention is employed, not only the life of the coke oven is extended, but also the amount of heat consumed in the coke oven is reduced, making an extremely large economic contribution.

Further, the repair method and apparatus can be effectively applied to gun-type duct repair.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a conventional repair method. In the figure, 1... Gas distribution branch pipe, 2... Tuyere pipe, 3
... Gas duct, 4 ... Combustion chamber, 5 ... Mortar tank, 6 ... Compressed air piping, 7 ... Mortar transport pipe, 8 ... Tuyere pipe insertion fitting, 9 ... Compressed air pot, 10 ... Mortar 11 indicates a heat storage chamber, 12 indicates an air hole, and 13 indicates a floor plate. FIG. 2 is a schematic diagram of the repair method of the present invention, and FIG. 3 is a schematic diagram of the repair device. In Figures 2 and 3, 1... Mortar pressure pump, 2... Mortar hopper, 3... Mortar transport pipe, 4... Mortar discharge port, 5... Packing, 6... Flexible connecting pipe, 7... Heat storage chamber,
8... shows a combustion chamber, 9... shows an air hole.

Claims (1)

[Scope of Claims] 1. A mortar discharge port is provided at the tip of the mortar transport pipe, and packing made of a heat-resistant material having approximately the same diameter as the gas duct is placed before and after the discharge port to form a mortar compression chamber together with the inner wall of the gas duct. A method for repairing a coke oven gas duct, which comprises using a repair device installed in such a manner as to press-fill mortar into a damaged part of the coke oven gas duct. 2. At the tip of the mortar transport pipe, a mortar discharge port and a discharge facility having a packing made of a heat-resistant material having approximately the same diameter as the gas duct and attached so as to form a mortar compression chamber together with the inner wall of the gas duct are installed before and after the mortar discharge port. Coke oven gas duct repair equipment installed in. 3. Claim 2, in which there are two or more packings each before and after the discharge port, which has the function of holding excess mortar and cleaning mortar adhering to the wall surface.
The coke oven gas duct repair device described in Section 1.