JPH06256065A - Refractory for hot repairing - Google Patents

Abstract

PURPOSE:To provide the durable hot-repairing refractory capable of efficiently repairing cracks and gas-leaking parts generated in the wall and end parts of the carbonization chamber of a coke oven and in places close to the coal- charging port. CONSTITUTION:The refractory for hot-repairing comprises 5-20wt.% of powdery sodium silicate having a SiO2/Na2O molar ratio of <=2.6, 1-8wt.% of clay, 0.1-0.6wt.% of a polyalkyl sulfonate salt and 10-20wt.% of alumina fine powder having a particle diameter of <=45mum, and the remaining amount of refractory powder having a particle diameter of <=0.5mm. The hot-repairing refractory gives a viscosity of <=4000cps when mixed with <=20 weight outer percent of water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refractory material for hot repair, which is used for repairing cracks in refractory near the end of a carbonization chamber of a coke oven or near a coal charging port.

[0002]

2. Description of the Related Art Conventionally, cracks, joint damages, and gas leaks that have occurred in the walls and ends of the coke oven of a coke oven cannot be repaired by cooling them during operation. Spray repair with semi-dry spray refractories has been performed between operations. The condition of the crack, joint damage portion and gas leak portion will be described with reference to the drawings.

FIG. 2 is an explanatory view showing a cross section of the end portion of a coke oven. 1 is a carbonization chamber for carbonizing the coke, 2 is a door frame made of cast iron fitted in the end portion of the carbonization chamber, and 3 is its door. Refractory material, 4 is a combustion chamber adjacent to the carbonization chamber 1, 5 is a brick of the furnace body, 6 is a protection ledge, 7 is a brick side protection ledge for protecting the outer end of the brick, 8 is a splash plate, and 9 is a back of the furnace. Although it is a stay, in the coke oven, due to expansion of the brick 5 of the furnace body and deformation of the cast iron door frame 2 due to the use of the oven for many years, joint breakage and cracks 13 of the brick are generated, and the brick 5 and the cast iron are made. Door frame 2
The crack 10 is generated in the clearance 10 between the protection ledge 6 and the brick-side protection ledge 7 and the clearance 12 between the brick-side protection ledge 7 and the brick 5 to cause a gas leak, resulting in non-uniform carbonization of coal. There was a problem such as. Table 1 shows the locations and causes of the cracks as a whole.

[0004]

[Table 1]

[0005]

However, the joint breaks and cracks 13 and cracks and gas leaks in each gap of the brick are repaired by spraying with a refractory material or spraying with a semi-dry spray refractory. However, the adhesion between the refractory material and the semi-dry sprayed refractory and the cast iron door frame 2 is poor, and cracks occur within several months during the thermal spray repair, and cracks after several weeks during the semi-dry sprayed refractory repair. Gas leakage occurs. Moreover, the spraying rate of the refractory material is less than 1kg / min, and the repair efficiency is poor. With the semi-dry spray refractory repair method, the discharge rate of the refractory material is 10 to 20kg / min, but the adhesion rate of the refractory material is 70%. At ~ 85%, the efficiency is poor and more dust is generated, resulting in a bad working environment.

On the other hand, the coke inlet of the coke oven is located on the upper surface of the oven, and a frame made of cast iron is fitted around it to prevent the coal outlet from collapsing. Problems such as cracks between the product and gas leaks and rainwater entering the carbonization chamber have occurred. For this reason, spray repair with the semi-dry spray refractory has been performed.

An object of the present invention is to provide a refractory material for hot repair which solves the above problems.

[0008]

[Means for Solving the Problems] The method of the present invention comprises: SiO ₂ / Na ₂ O
5 to 20% by weight of sodium silicate powder having a molar ratio of 2.6 or less, 1 to 8% by weight of clay, 0.1 to 0.6% by weight of polyalkylallyl sulfonate, and an alumina fine powder having a particle size of 45 μm or less It is a refractory material for hot repairs, characterized in that it consists of 10 to 20% by weight and the rest of it is a refractory powder with a particle size of 0.5 mm or less. The refractory material for hot repair is characterized in that the viscosity obtained at the time is 4000 cps or less.

[0009]

According to the method of the present invention, the composition of the refractory material for hot repair can be changed.
5 to 20% by weight of powdered sodium silicate having a SiO ₂ / Na ₂ O molar ratio of 2.6 or less, 1 to 8% by weight of clay, and 0.1 to 0. 0 of polyalkylallyl sulfonate which is an organic high-performance surfactant.
10 to 20% by weight of fine alumina powder with a particle size of 45 μm or less at 6% by weight
% By weight, and the balance was made to contain refractory powder having a particle size of 0.5 mm or less.

That is, since sodium silicate is thermosetting and has fluidity at room temperature, it has excellent workability.
Since it reacts with free lime or carbon dioxide to generate lime silicate, and the lime silicate fills the voids to improve the airtightness, the lime silicate that has been filled in the cracks and reacted can prevent water permeation and gas permeability. However, if the powdered sodium silicate is less than 5% by weight, less lime silicate is formed, and when the temperature of the powdered sodium silicate is 400 ° C or higher, the volume expansion due to the bubbles is also small, and the airtightness of the portion is improved even if the crack is filled. The effect of causing it is small. If the content of the powdered sodium silicate exceeds 20% by weight, the foaming of the powdered sodium silicate becomes too large, and the filled material becomes foamy to lower the airtightness.

40 powders of sodium silicate and refractory powder alone
To obtain a viscosity of 00 cps or less, 30% or more of water is required to be applied on the outside, and when this irregular shaped refractory is heated after construction, the water becomes steam and is discharged, causing voids and cracks inside. Since the airtightness of the irregular shaped refractory cannot be maintained, polyalkylallyl sulfonate, which is an organic high performance surfactant, was added as a water reducing agent. By adding 0.1-0.6% by weight of polyalkylallyl sulfonate to the refractory powder that uses powdered sodium silicate as a sintering hardening agent, the amount of water added to the amorphous refractory can be reduced, and hot work filling can be performed. However, it was found that blistering due to evaporation of kneading water did not occur, and in addition to that, by adding 1 to 8% by weight of clay, water can be further reduced and fluidity increased.

When the content of polyalkylallyl sulfonate is less than 0.1% by weight or more than 0.6% by weight, it is difficult to control the fluidity of the amorphous refractory and the added water content. Kaolin clay is most suitable as the clay, but if it is less than 1% by weight or more than 8% by weight, it is also difficult to control the fluidity and the added water content of the amorphous refractory. Further particle size
By adding 10 to 20% by weight of alumina fine powder having a particle size of 45 μm or less to the amorphous refractory, it becomes possible to increase the sintering power and strength of the material after filling the irregular refractory. However
If it is less than 10% by weight, the increase in strength is small, and if it exceeds 20% by weight, the viscosity increases and it is difficult to fill cracks.

The remaining refractory powder has a grain size of 0.5 mm or less as a grain size that can be filled in cracks, and its material is hot expansive kyanite sand or under-leucite,
Alternatively, bauxite, fused alumina, sintered alumina, high alumina, mullite, silica stone and silica sand may be used. Also, the viscosity obtained when kneading by adding 20% by weight or less of water on the outside is 4000 cps or less, so cracks are filled efficiently, and even after heating, cracks do not occur and the life of the coke oven can be extended. Becomes

[0014]

Embodiments of the present invention will be described below with reference to the tables and the drawings. Table 2 shows examples and comparative examples of the present invention.

[0015]

[Table 2]

Both the samples No. 1 and No. 2 of the examples have higher adhesive strength after firing than the comparative examples, and the air permeability after firing is also much smaller than that of the comparative examples. That is, it was found that the samples of Examples after being filled in the cracked portions of the furnace and heated were firmly filled in the cracked portions of the furnace and were bonded to each other, and the gas permeability was significantly small.

As shown in FIG. 1, the above-mentioned embodiment, ie, the hot repair refractory material according to the present invention, has a small press-fitting device 17 for press-fitting the hot repair refractory material into the crack of the furnace, and the hot repair refractory material. SGP pipe 14 for press-fitting refractory material with a diameter of 15 mm and length of 2 m, and a hose connecting the pipe 14 and the compact press-fitting device 17.
A refractory material press-fitting machine consisting of 16 and a coupler 15, and cracks and gas leaks in the gap 12 between the furnace brick 5 and the brick side protection ledge 7, and cracks in the gap 11 between the brick side protection ledge 7 and the protection ledge 6. And gas leaks and the gap 10 between the door frame 2 and the protection ledge 6
It was press-fitted into the cracked portion and the gas leak portion.

After that, when the gas leak state of the furnace was observed, it was found that the hot repair refractory material of the present invention was used for 6 months or more as compared with the gas leak durability of the comparative example of 7 days to 1 month. Even gas leak durability was no problem. (See Table 2)

[0019]

Effects of the Invention By filling the refractory material for hot repairing of the present invention into cracks and gas leaks at the end of the carbonization chamber of the coke oven, and around the coal charging port metal frame of the furnace top, the combustion chamber to the carbonization chamber is filled. Gas leaks can be prevented for 6 months or more, and smoke and dust can be prevented from the vicinity of the kiln opening in the carbonization chamber, while rainwater can be prevented from entering the carbonization chamber from the vicinity of the metal frame at the furnace top.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a method for repairing a crack portion or a gas leak portion at an end portion of a coke oven carbonization chamber by a hot repair refractory material of the present invention.

FIG. 2 is a cross-sectional explanatory view showing a crack or a gas leak at the end of the coke oven carbonization chamber.

[Explanation of symbols]

1 Carbonization chamber 2 Door frame 3 Door refractory 4 Combustion chamber 5 Brick 6 Protection ledge 7 Brick side protection ledge 8 Splash plate 9 Backstay 10 Gap between furnace body and door frame 11 Gap between protection ledge and brick side protection ledge 12 Gap between the brick side protection ledge and the brick 13 Broken brick joints and cracks 14 SGP pipe for press-fitting refractory material 15 Coupler 16 Hose 17 Small press-fitting device

Claims (2)

[Claims] 1. A powdery sodium silicate having a SiO ₂ / Na ₂ O molar ratio of 2.6 or less is 5 to 20% by weight, and clay is 1 to 8% by weight.
And 0.1 to 0.6% by weight of polyalkylallyl sulfonate, 10 to 20% by weight of fine alumina powder having a particle size of 45 μm or less, and the balance consisting of refractory powder having a particle size of 0.5 mm or less. A refractory material for hot repair. 2. The refractory material for hot repair according to claim 1, wherein the viscosity obtained when kneading by adding 20% by weight or less of water to the outside is 4000 cps or less.