KR101875149B1 - Binder and for repairing method for furnace body using the same - Google Patents

Abstract

The present invention relates to an adhesive material and a method for repairing a nozzle body using the adhesive material, A process of preparing an adhesive material; Forming an adhesive layer by spraying the adhesive onto the inner wall of the furnace body; And a step of spraying the repair material onto the adhesive layer to form a repairing material layer. In order to improve the adhesion between the repairing material used for repairing the furnace body, for example, the amorphous refractory and the refractory and the dissimilar materials previously installed in the furnace body .

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a binder and a repairing method,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive material and a method for repairing a furnace body using the same, and more particularly, to an adhesive material for improving refractory repairability by improving adhesion of different materials and a furnace body repairing method using the same.

The structure of the blast furnace is made of iron, and the inside is constructed of refractory capable of withstanding high temperature (inside fire resistance), and a cooling fan is inserted between the fire resistance to cool the refractory to protect the iron at high temperature.

However, as the number of days of use of the blast furnace increases, mechanical abrasion occurs due to the fall of the charge or contact with the iron wire, and the cooling zone is exposed due to the damage of the refractory due to the high temperature and chemical reaction inside the blast furnace. As a result, Heat and cracks occur, which makes the operation unstable.

In order to solve this problem, the charge in the blast furnace is lowered to the repair range of the furnace wall, and a refractory such as unshaped refractory is sprayed on the damaged refractory inside the blast furnace by using spray equipment.

However, because the unshaped refractory does not have its own adhesive strength, its adhesion with refractories inside the blast furnace is not great, and since the abrasion of the refractory is inevitable due to its operating characteristics, its lifetime is as short as 2 to 3 months, In addition, if the refractory damage is severe, the cooling plate or the screed may be exposed. In this case, the irregular refractory is not adhered to the cooling plate or the screed.

KR 0406437 B KR 2000-0067290 A

The present invention provides an adhesive composition excellent in dissimilar materials and adhesion, and a nozzle body repair method using the same.

The present invention provides an adhesive composition capable of improving the refractory life of a furnace body and a furnace body repair method using the same.

The adhesive material according to the embodiment of the present invention may contain 51 to 53% by weight of Al ₂ O ₃ , 42 to 44% by weight of SiO ₂ , and 3 to 7% by weight of a curing agent based on 100% by weight of the total.

The average particle size of Al ₂ O ₃ and SiO ₂ may be more than 0 and 0.3 mm or less.

The settable material may include an alkali-silicate glass aqueous solution.

The settable material may include sodium silicate.

A method for repairing a furnace body according to an embodiment of the present invention includes the steps of: preparing a repair material; A process of preparing an adhesive material; Forming an adhesive layer by spraying the adhesive onto the inner wall of the furnace body; And forming a repair material layer by spraying the repair material onto the adhesive layer.

The repair material may include a monolithic refractory material.

The process of preparing the adhesive may include mixing 51 to 53% by weight of Al ₂ O ₃ , 42 to 44% by weight of SiO ₂ and 3 to 7% by weight of a curing material with respect to 100% have.

At least one of the process of forming the adhesive layer and the process of forming the repair material layer may be performed at a temperature of 100 ° C or less.

The inner wall of the furnace body may include at least one of a refractory material, a cooling plate, and a screed, and the adhesive layer may be formed on at least one of the refractory material, the cooling plate, and the screed.

The curing material may include sodium silicate and the step of providing the adhesive may control the content of the sodium silicate to control the curing time of the adhesive.

According to the embodiment of the present invention, it is possible to improve the adhesion between the repair material used for repairing the furnace body, for example, the irregular refractory material, and the refractory material and the dissimilar material previously provided in the furnace body. Therefore, the durability of the refractory and the repair material can be improved to shorten the maintenance period of the furnace body, thereby shortening the downtime of the furnace body and improving the productivity.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual view of a nozzle body repairing method according to an embodiment of the present invention; FIG.
BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]
3 is a test pattern diagram for verifying the adhesive effect of the adhesive used in the nozzle body repairing method according to the embodiment of the present invention.
Fig. 4 is a graph showing change in curing time of the adhesive according to the amount of the curing material in the adhesive. Fig.
FIG. 5 is a graph showing a change in calorific value of blast furnace cooling water over time after completion of blast furnace repair.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know. Wherein like reference numerals refer to like elements throughout.

The present invention can be applied to repairing containers, such as blast furnaces, converters, laddles, tundishes, vessels, etc., where high temperature melts are charged. Such a container may include a refractory material and a wick surrounding the refractory material, and may include a cooling zone (or stave) between the refractory material and the wick to protect the refractory material and the wick. In the embodiment described below, an example of repairing the refractory in the blast furnace will be described.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual view illustrating a method of repairing a nozzle body according to an embodiment of the present invention; FIG.

Referring to FIG. 1, the blast furnace 100 may include a body 110 containing a raw material such as coke, iron ore, etc., and the body 110 may include a refractory 114, And a screed 112 provided to surround the refractory 114. Between the refractory 114 and the metal foil 112 is provided a cooling plate 120 for circulating cooling water to prevent the refractory 114 and the metal foil 112 from being excessively heated.

A furnace 116 is formed in the upper part of the body 110 to supply raw materials for producing iron ores such as iron ore, sintered ore and coke. A furnace 116 is provided with a raw material input device .

A tuyere 130 for supplying hot air into the body 110 and an outlet 140 for discharging a molten iron produced by dissolving the raw material may be formed in the lower portion of the body 110.

In the course of manufacturing the molten iron using the blast furnace 100, the raw materials such as iron ore and coke are continuously supplied through the furnace 116. As a result, the refractory material 114 on the inner wall of the blast furnace 100 is rubbed The refractory 114 may wear and become damaged.

The cooling plate 120 buried in the refractory 114 is exposed to the inside of the blast furnace 100 and the inside of the blast furnace 100 is exposed to the inside of the blast furnace 100. As a result, There is a problem of accelerating the heat generation and cracking of the substrate 112.

Therefore, the repair of the refractory 114 is performed periodically or as needed. The refilling of the refractory 114 is mainly performed by injecting the spray through the furnace 116 and spraying the irregular refractory onto the inner wall of the blast furnace 100 Has been used.

However, when the refractory 114 is coated with a monolithic refractory for repairing the refractory 114, the adhesion between the existing refractory 114 and the newly applied irregular refractory is poor, shortening the maintenance period, There is a problem that the productivity of the charcoal is lowered due to the stop of the operation. In particular, when the refractory 114 is worn or damaged, the cooling plate 120 or the foil 112 buried in the refractory 114 may be exposed. In this case, since the adhesion to the refractory 114 is insufficient, There is a difficult problem.

In the present invention, an adhesive material is applied before injecting and spraying a monolithic refractory on the wall of a furnace to improve the adhesion between the monolithic refractory and the refractory 114, and to improve the adhesion between the refractory material and the refractory material 114, The adhesive strength can be improved.

The adhesive material according to the embodiment of the present invention comprises 51 to 53% by weight of Al ₂ O ₃ , 42 to 44% by weight of SiO ₂ , 3 to 7% by weight of the first hardening material, and Al ₂ O ₃ , SiO ₂ and 0.8 to 5% by weight of the second hardening material based on 100% by weight of the first hardening material. At this time, Al ₂ O ₃ and SiO ₂ have an average particle size of more than 0 to 0.3 so as to increase the specific surface area and to improve adhesion to the different materials such as the refractory 114, the cooling plate 120, Mm or less.

Here, Al ₂ O ₃ and SiO ₂ are provided in a powder state, and the setting material is provided in a liquid phase. Al ₂ O ₃ and SiO ₂ form a solid-phase bond and form an adhesive layer 210, and the first and second hardening materials serve to fix the thus formed adhesive layer 210 to the wall of the furnace. At this time, SiO ₂ has a property of changing into a liquid state at a high temperature. Therefore, when the content of SiO ₂ is larger than the range, it is difficult to maintain the adhesive layer formed on the wall of the furnace after flowing through the furnace wall after repairing the furnace body. When the content of SiO ₂ is less than the range shown in Table ₁ , the bond strength with Al ₂ O ₃ is lowered and it is difficult to maintain the adhesive layer 210 formed on the wall of the furnace.

In addition, when the content of Al ₂ O ₃ is less than the suggested range, the content of SiO ₂ increases relatively, which makes it difficult to maintain the adhesive layer 210 in a high-temperature operating environment after repairing the furnace wall. In addition, when the content of Al ₂ O ₃ is larger than the range shown in Table _1, the content of SiO ₂ is relatively decreased and the bonding force with Al ₂ O ₃ is decreased, so that it is difficult to maintain the adhesive layer 210 formed on the wall of the furnace.

Also, when the content of the first hardened material is less than the specified range, it is difficult to maintain the adhesive layer 210 formed on the wall of the furnace due to the reduced adhesion with the furnace wall. When the content is larger than the range, There is a problem that it is difficult to form the adhesive layer 210.

The second hardened material hardens the adhesive layer 210 so that the adhesive layer 210 can be formed on the furnace wall in the process of spraying the adhesive material on the furnace wall. If the content of the second hardened material is less than the specified range, it is difficult to form the adhesive layer 210 on the wall of the furnace because the hardening of the adhesive is delayed, The bonding strength between the resin and the resin can be reduced.

As the first set material, an alkali-silicate glass aqueous solution may be used, and as the second set material, sodium silicate may be used. At this time, the alkali-silicate-based glass aqueous solution, which is the first set material, can form a liquid so that Al ₂ O ₃ and SiO ₂ provided as powders can be sprayed. However, since the first curing material is cured at a temperature of 100 ° C or higher, the repair of the furnace wall is performed at a temperature of 100 ° C or lower, and the adhesive layer is not maintained in the form of the sprayed material when the adhesive layer is formed on the wall of the furnace.

Therefore, it is possible to maintain the adhesive layer on the wall of the furnace by further using the second hardening material which can be cured at a relatively low temperature, for example, 100 DEG C or less. Sodium hexafluoride used as the second set material can be cured while absorbing moisture contained in the first set material that is in a liquid state with a strong oxidizing agent. Therefore, when the adhesive material is sprayed onto the wall of the furnace, the adhesive material layer can be formed while the second set material is cured. At this time, the moisture contained in the first hardened material is removed by the second hardened material, and the film quality of the adhesive layer 210 becomes dense, which may delay damage or wear which may occur in the subsequent blast furnace operation.

In addition, the curing time of the adhesive material can be adjusted according to the content of the second curing material. For example, the greater the amount of the second hardening material, the shorter the curing time of the adhesive material.

Hereinafter, a method for repairing the furnace wall using the adhesive material will be described.

2 is a flowchart sequentially illustrating a method for repairing a nozzle body according to an embodiment of the present invention.

Referring to FIG. 2, a method of repairing a furnace body according to an exemplary embodiment of the present invention includes a step S110 of providing a monolithic refractory material, a step S112 of providing an adhesive material, a step S114 of applying an adhesive material to the inner wall of the furnace body And a step S116 of applying a monolithic refractory material on the adhesive material. At this time, the furnace body repair can be performed at a temperature of 100 ° C or less.

The amorphous refractory may have fluidity to be applied to the furnace wall through spraying. The monolithic refractory may include refractory aggregate portions such as alumina, magnesia, and chromia, and a fine powder portion composed of refractory fine particles and an inorganic binder such as alumina cement. In addition, it may contain moisture to have fluidity and moldability. Further, the fine powder part may include a granular inorganic admixture such as silica fume or reactive alumina which can diversify the particle size distribution. In addition, the amorphous refractory may include an organic admixture such as a plasticizer, an air-trapping agent, a condensation modifier, etc. for improving the characteristics.

In addition, the irregular refractory may be mixed with the rapid setting agent just before being sprayed on the furnace wall, thereby increasing the deposition rate on the furnace wall.

Such a monolithic refractory is a well-known technology and a detailed description thereof will be omitted.

The adhesive may be prepared by spraying a mixture of Al ₂ O ₃ , SiO ₂ , the first set material and the second set material. At this time, an alkali-silicate-based glass aqueous solution may be used as the first set material, and sodium silicate may be used as the second set material. The adhesive material comprises 51 to 53 wt.% Of Al ₂ O ₃ , 42 to 44 wt.% Of SiO ₂ and 3 to 7 wt.% Of the first set material, 100 wt.% Of Al ₂ O ₃ , SiO ₂ and And may include a second set material for 100 wt% of the first set material mixture. At this time, since the second hardened material is hardened at a temperature of 100 ° C or less at which the nozzle body repair is performed, it is preferable to mix the adhesive with a mixture of Al ₂ O ₃ , SiO ₂ and the first hardening material just before spraying the adhesive. In addition, the curing time of the adhesive layer formed on the furnace wall can be controlled by controlling the content of the second set material.

When the irregular refractory material and the adhesive material are provided, the adhesive material is sprayed onto the surface of the furnace wall by a spraying method to form the adhesive material layer 210. At this time, the adhesive layer 210 can be formed on the surface of the refractory 114 installed in the base. In the portion where the refractory 114 is abraded or damaged, the refractory 114, the cooling plate 120, As shown in Fig.

At this time, the second curing material contained in the adhesive material is a strong oxidizing agent and can be cured while absorbing the moisture contained in the first curing material among the adhesive materials. At this time, when the adhesive material is sprayed onto the furnace wall, the adhesive material layer 210 is formed while being hardened by the second hardening material, but is not completely hardened.

When the adhesive layer 210 is formed on the furnace wall, the repair material layer may be formed by spraying a monolithic refractory on the surface or upper surface of the adhesive layer 210. At this time, the monolithic refractory is sprayed before the adhesive layer 210 is completely cured, so that the second set material contained in the adhesive layer 210 absorbs water contained in the monolithic refractory material and hardens to thereby cure the adhesive layer 210 and the monolithic refractory material It is possible to improve the bonding force between the layers of the repairing material formed by the adhesive layer.

Hereinafter, an experimental example for verifying the effect of repairing the blast furnace by the furnace body repairing method according to the embodiment of the present invention will be described.

FIG. 3 is a test pattern diagram for verifying the adhesive effect of the adhesive material used in the nozzle body repairing method according to the embodiment of the present invention, FIG. 4 is a graph showing the change in the curing time of the adhesive material according to the amount of the second hardening material, FIG. 5 is a graph showing a change in calorific value of the blast furnace cooling water over time after blast repair.

First, when a repair material layer is formed by forming an adhesive layer using an adhesive material according to an embodiment of the present invention on a furnace wall, it is possible to use a different material such as a refractory, a repair material layer, 3-point bending strength test was conducted as shown in Fig. 3 to confirm the adhesion between the layers of the repairing material.

The experiment was carried out using the four adhesives shown in Table 1 below.

A B C D Adhesive component SiO ₂ .nH ₂ O A + magnesium sulfate Alkali-silicate glass aqueous solution Al ₂ O ₃ , SiO ₂ , alkali-silicate glass aqueous solution,
Sodium silicate mixture Refractory kgf / cm ² 15 - - 101 Heterogeneous material kgf / cm ² - - - 104

As shown in Table 1, when the adhesive layer containing SiO ₂ · nH ₂ O was used to form an adhesive layer, a repair layer was attached to the refractory provided on the inner wall of the blast furnace, but the adhesion strength was 15 kgf / cm ² . However, when the adhesive material A was used, the layer of the repair material was not adhered to the different material. In the case of using the adhesive material B prepared by mixing the adhesive material A and magnesium sulfate and using the adhesive material C containing the alkali-siliceous glass aqueous solution, there was no adhesion of the repair material layer to the refractory material as well as the different materials. Since the alkali-silicate glass aqueous solution is cured at a temperature of 100 ° C or higher, it is difficult to form an adhesive layer when an adhesive is sprayed on the wall of the furnace.

Also, when the adhesive material D prepared according to the embodiment of the present invention was used, the repair material layer adhered to both the refractory material and the dissimilar material, and the adhesion strength thereof was very high, 101 and 104 kgf / cm ² .

Next, the curing time of the adhesive layer was measured according to the content of the second curing material in the adhesive.

First, the content of the second hardening material was changed to 0.2 wt%, 0.8 wt%, 1 wt%, 5 wt% and 8 wt%, and thus the contents of Al ₂ O ₃ and SiO ₂ were controlled, , Adhesive 3, adhesive 4 and adhesive 5 were produced.

Then, the adhesive material 1 to the adhesive material 5 were sprayed onto the furnace wall of the furnace to form an adhesive material layer, and the curing time of the adhesive material layer was measured and shown in FIG.

When the adhesive 1 was used, it took about 22 hours for the adhesive layer to fully cure. If the time required for the adhesive layer to harden is long, the adhesive layer is hardly cured when the adhesive layer is sprayed onto the wall, which makes it difficult to form an adhesive layer on the wall.

When the adhesives 2 to 4 are used, the adhesive layer is smoothly formed on the wall of the furnace, and the curing time of the adhesive layer is remarkably shortened as compared with the case of using the adhesive 1.

On the other hand, in the case of the adhesive 5, the curing time was not measured because the content of the curing material was too large to allow the adhesive material Z to flow down from the furnace wall to form an adhesive layer.

As a result, it is possible to control the formation of the adhesive layer and the time required for repairing the furnace wall according to the amount of the second hardening material in the adhesive, and it is possible to dramatically shorten the repair time of the furnace wall when the second hardening material is used properly I could.

The maintenance effect of the blast furnace body can be calculated using the calorific value of the cooling water used to cool the furnace body. Therefore, in order to confirm the maintenance effect of the inner wall of the blast furnace by repairing the inner wall of the blast furnace according to the embodiment of the present invention, the variation of the heat of the cooling water with time after the repairing of the furnace body was measured.

FIG. 5 (a) shows a change in the amount of heat of cooling water with time after repairing the furnace body, when the furnace body is repaired by directly spraying the monolithic refractory on the furnace wall without using an adhesive. 5 (a), the average calorific value of the cooling water was measured to be about 11,800 Mcal / Hr up to about 50 days after the maintenance of the furnace body, but after about 50 days, the average calorific value of the cooling water was about 14,200 Mg / Hr , And it was found that it was increased by about 3000 Mcal / Hr.

FIG. 5 (b) shows the change in the amount of heat of the cooling water over time after repairing the furnace body when the furnace body is repaired by spraying the monolithic refractory after forming the adhesive layer on the furnace wall according to the embodiment of the present invention. Referring to FIG. 5 (b), the average calorific value of the cooling water was measured to be about 11,548 Mcal / Hr until about 140 days passed after the furnace body was repaired. After about 140 days, the average calorific value of the cooling water was measured to be about 12,293Mcal / Hr and increased by about 1000Mcal / Hr.

The result of this experiment shows how long the maintenance material layer is maintained on the wall after repairing the furnace body. Thus, when repairing the furnace wall by the furnace repairing method according to the embodiment of the present invention, It can be seen that the period can be shortened. That is, when the repair material layer is worn or damaged after repairing the furnace body, it means that the distance between the cooling chamber embedded in the refractory and the inner space of the blast furnace is reduced or exposed in the furnace.

Although the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be defined by the appended claims and equivalents thereof.

100: Blast furnace 110: Body
112: scrap 114: refractory
210: adhesive layer 220: repair material layer

Claims (10)

As adhesives for attaching different kinds of materials,
51 to 53% by weight of Al ₂ O ₃ , 42 to 44% by weight of SiO ₂ , and 3 to 7% by weight of an alkali-silicate glass aqueous solution, based on 100%
Extrapolated, the curable silicon fluoride soda below 100 ℃ the Al ₂ O _3, SiO ₂ and an alkali-containing adhesive material of 0.8 to 5% by weight relative to the silicate-based glass solution 100% by weight. The method according to claim 1,
Wherein the average particle size of Al ₂ O ₃ and SiO ₂ is more than 0 and 0.3 mm or less. delete delete 1. A method of repairing a furnace body including a refractory, a wick surrounding the refractory, and a cooling unit provided between the refractory and the wick,
The process of preparing a monolithic refractory;
A process of preparing an adhesive material;
Forming an adhesive layer by spraying the adhesive onto the surface of at least one of the metal foil and the cooling foil; And
Forming a refractory layer by spraying the monolithic refractory on the adhesive layer;
/ RTI >
In the process of preparing the adhesive,
Mixing 51 to 53% by weight of Al ₂ O ₃ , 42 to 44% by weight of SiO ₂ and 3 to 7% by weight of an alkali-silicate glass aqueous solution, based on 100%
Comprising the step of mixing 0.8 to 5% by weight of sodium silicate with 100% by weight of the mixture of Al ₂ O ₃ , SiO ₂ and alkali-silicate glass aqueous solution so as to be cured at 100 ° C. or lower, Way. delete delete The method of claim 5,
Wherein at least one of the process of forming the adhesive layer and the process of forming the repair material layer comprises:
A method for repairing a furnace body which is performed at a temperature of 100 DEG C or less. delete The method of claim 8,
Wherein the step of preparing the adhesive material comprises adjusting the content of the sodium silicate to control the curing time of the adhesive material in the process of forming the adhesive material layer.

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