JPH1036178A - Mud material for tapping port of blast furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a mud material for tapping port of a blast furnace capable of readily automatically packing into a mud gun by including a binder obtained by dissolving a novolak type phenol resin into ethylene glycol monoethyl ether and a specific curing agent. SOLUTION: This mud material uses a resin-based binder and comprises a binder obtained by dissolving a novolak type phenol resin into ethylene glycol monoethyl ether and/or diethylene glycol monoethyl ether and hexamethylene tetramine. The mud material has proper fluidity and curing rate by heating of an automatic packing device by using a novolak type phenol resin having 601-700 number-average molecular weight as the novolak type phenol resin and provide dense constructed body excellent in corrosion resistance after packing into an tapping port. Ethylene glycol monoethyl ether in an amount of 20-40wt.% based on outer percentage is preferably added to the resin in an amount of 100wt.%. Attachment of the resin to the automatic packing device is prevented by the solvent. A refractory blend of the mud material is preferably carried out by conventional combination with alumina, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mud material for a blast furnace taphole using a resin binder.

[0002]

2. Description of the Related Art In recent years, as a part of work improvement in front of a blast furnace, the use of an automatic filling device has been proposed for charging a blast furnace taphole mud material into a mud gun (Japanese Patent Publication No. 53-1448).
No. 3).

[0003] The material of the mud material is generally a mixture of a refractory raw material such as alumina powder, silicon carbide, clay powder and coke, and a tar-based binder such as tar and pitch (see, for example, JP-A-1-11-1).
No. 08170) or a resin binder such as a phenol resin or a phenol-modified resin (for example, JP-A-4-28).
No. 0878).

[0004]

An automatic filling device for filling a mud gun with a mud material is equipped with a heat retaining device and a vibrating device to facilitate the filling.

[0005] The mud material of the tar-based binder (hereinafter referred to as tar-based mud material) is heated to 50 to 10 by a heat retaining device.
When the heating is performed at about 0 ° C., the viscosity is reduced, and the vibrating device is brought into a fluid state, so that the operation of filling the mud gun is performed without any trouble.

However, since the tar-based mud material is filled with a tapping hole from a mud gun due to thermoplasticity, it takes a long time for thermosetting, and the holding time by the mud gun becomes longer, so that the efficiency of closing the tap hole is reduced. bad. Further, the tar-based binder emits remarkable smoke and dust at the time of opening, which is not preferable in terms of working environment.

On the other hand, a mud material made of a resin-based binder (hereinafter referred to as a resin-based mud material) cures quickly after the tap hole is closed, and has no problem of smoke and dust at the time of opening. Due to these advantages, mud materials are shifting from tar-based to resin-based.

However, in the case of a resin-based mud material, when an automatic filling device is used, rapid supply cannot be performed due to adhesion to the inner wall of the insertion tube, and an operation of removing the attached material is added. There was a problem that the effect of efficiency improvement was not fully utilized.

Further, it has been known that a solvent such as ethylene glycol or propylene glycol is added to impart fluidity to the resinous mud material. However, it is not effective in preventing adhesion and is provided with an automatic filling device. The solvent is volatilized by the heating device and the fluidity is reduced by thermal drying. In addition, there is a problem that the solvent is rapidly volatilized due to rapid heating when the taphole is closed, thereby weakening the structure of the construction body.

It is an object of the present invention to solve the above-mentioned problems in a resin-based mud material to be filled into a mud gun by using an automatic filling device.

[0011]

According to the present invention, there is provided a blast furnace tapping characterized by comprising a binder comprising a novolak type phenol resin dissolved in ethylene glycol monoethyl ether and / or diethylene glycol monoethyl ether, and hexamethylenetetramine. It is a mud material for holes.

According to the present invention, the use of ethylene glycol monoethyl ether and / or diethylene glycol monoethyl ether as a solvent is effective in preventing adhesion to the inner wall of the insertion tube when using an automatic filling device.

Although the detailed mechanism of the effect of these solvents for preventing adhesion is not clear, one of the molecules has a hydroxyl group which is easily compatible with the phenol resin as a molecular property, and the other has a hydroxyl group which is familiar with the phenol resin. As a result of the ethers having an ethyl group having difficult properties, it is considered that the structure is such that the hydroxyl group is directed to the resin side and the ethyl group is directed to the outside to surround the resin.

In the blast furnace tapping mud material, the novolak type phenol resin has a number average molecular weight of 6
In the case of using a material of 01 to 700, an appropriate fluidity and a hardening rate are obtained by receiving heat from a heating device provided in an automatic filling device, and after filling into a taphole, a dense and excellent corrosion resistance is obtained. A construction body is obtained.

These effects obtained by setting the number average molecular weight of the novolak phenolic resin to 601 to 700 are unique to the present invention, and the mechanism is not clear, but is remarkable only in combination with the above-mentioned solvent. Is obtained.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, ethylene glycol monoethyl ether used as a solvent for a novolak type phenol resin is C ₂ H ₅ OCH ₂ CH ₂ OH, molecular weight 9
0, specific gravity 0.93 (20/20 ° C), boiling point 135 ° C (7
60 mm / Hg). On the other hand, diethylene glycol monoethyl ether is C ₂ H ₅ (OCH ₂ CH ₂ )
₂ OH, molecular weight 134, specific gravity 0.99 (20/20
° C) and a boiling point of 203 ° C (760 mm / Hg).

Although these are conventionally known as solvents for resins, they have never been used as solvents for binders of mud materials. This is in part due to the fact that there has never been a need to provide a supply capacity in an automatic filling device.

According to the present invention, the mud material to be filled by using the automatic filling device is effective in preventing adhesion to the inner wall of the insertion tube of the automatic filling device. The amount of the solvent to be added to the resin is 20 to 40% by weight based on 100% of the resin.
wt% is preferred. If it is less than 20 wt%, the effect of preventing adhesion is insufficient, and if it exceeds 40 wt%, the volatile content is too large, and the corrosion resistance and structure strength of the mud material tend to decrease.

In order to provide the fluidity required for the filling operation by the automatic filling device, it is necessary to lower the viscosity of the mud material when heated at about 50 to 100 ° C. Heating at a high temperature is because fluidity cannot be obtained due to evaporation or thermal curing of the solvent. Although it fluctuates slightly depending on the performance of the automatic filling device, the flow when the vibration of 4 G is applied to the mud material for 10 seconds.
The value is 13 using a flow cone of JIS: R-2521.
It is preferably 0 mm or more.

The mud material must also have corrosion resistance and tap hole closing workability. Resin-based mud materials having automatic workability are generally less residual carbon than tar-based mud materials, exhibit insufficient carbon bonding, and are inferior in corrosion resistance and peeling damage resistance during tapping.

The resin-based mud material has the advantage that it cures quickly after filling the tap hole. However, there is a case where the heat hardening occurs more quickly than necessary, and the supply of the mud material to the automatic filling device becomes impossible, and further, the filling of the tap hole becomes difficult (non-pressing).

According to the present invention, the novolak type phenol resin used as a binder has a number average molecular weight of 60.
By setting it to 1 to 700, the amount of residual carbon is high in combination with the solvent, and an appropriate fluidity and curing time can be secured.

In the case of a material using a resin solution obtained by mixing a novolak-type phenol resin having a number average molecular weight of less than 601 with a solvent, a long time is required for thermosetting, and the holding time of the mud gun at the time of closing the tapping iron is preferably long. Absent. The specific curing time is desirably adjusted to a curing time at 200 ° C. of 600 seconds or less.

If the number average molecular weight is less than 601, the residual carbon content after firing is smaller than that of the conventional mud material, which is not desirable from the viewpoint of the structure of the mud material. The residual carbon content is important for binding aggregate particles and contributing to improvement of various properties such as material strength and corrosion resistance. If the residual carbon content is small, the structure of the mud material becomes coarse, which causes a significant decrease in corrosion resistance during tapping. Further, since the formation of carbon bond becomes difficult and the development of strength is remarkably impaired, peeling damage of the mud material during tapping is promoted, leading to shortening of tapping time.

Conversely, when aiming at shortening the time for thermosetting or designing a material having a large amount of residual carbon, the amount of hexamethylenetetramine used as a curing agent is increased, and the use of a thermosetting resol type phenol resin is increased. These phenolic resins are thought to be formed in combination, but these phenolic resins are liable to change over time such as thermosetting, and there is a risk that mud material cannot be supplied by the automatic filling method, and there is a risk of non-pressing when tapping is blocked, which is undesirable. .

In the case of a material using a resin solution obtained by mixing a novolak-type phenol resin having a number average molecular weight exceeding 700 with a solvent, when the tap hole is clogged, the material hardens quickly and the mother material in the hot tap hole has a high temperature. This is undesirable in that the adhesiveness to the material is deteriorated, and peeling damage of the mud material during tapping is promoted, leading to a reduction in tapping time. Specifically, it is desirable to adjust the curing time at 200 ° C. so as to secure 180 seconds or more.

If the number average molecular weight exceeds 700, the viscosity of the resin solution also increases, which is not desirable because the kneading workability and the workability at the time of automatic filling into a mud gun are inferior. Even if the solvent of the present invention, ethylene glycol monoethyl ether and / or diethylene glycol monoethyl ether, is administered to such a resin, the automatic filling workability cannot be sufficiently corrected.

The addition ratio of the resin solution obtained by adding and mixing the solvent to the novolak phenol resin is not particularly different from the addition ratio of the resin in the conventional material.
It is preferably 15 to 25 wt% on the basis of 00%. If it is less than 15% by weight, the effect as a binder is inferior.
If it exceeds less than 5 wt%, the corrosion resistance is reduced.

Further, an appropriate amount of hexamethylenetetramine is used as a curing agent for the resin solution. The preferable addition ratio is 0.1 to 3% by weight based on the outer volume of the novolak type phenol resin.

The refractory composition of the mud material is adjusted by combining, for example, alumina, alumina-silica, silica, high alumina, magnesia, magnesia-calcia, spinel, carbide, nitride, carbon, coke, clay, various metals and the like. It is no different from the conventional one.

[0031]

Examples Examples of the present invention and comparative examples will be described below.

Table 1 shows the common refractory formulations used in each example. Table 2 shows the test results along with the number average molecular weight of the novolak phenolic resin and the type of solvent added to the refractory composition shown in Table 1.

In Table 2, the amount of the solvent added is an outer value for the novolak type phenol resin. The amount of each resin solution shown in Table 2 to be added to the refractory formulation was 20 wt% in an outer case with respect to 100 wt% of the refractory formulation. In addition, although not shown in the same table, in any case, hexamethylenetetramine was used as a curing agent in a ratio based on 100% by weight of a novolak-type phenol resin solution.
0.5 wt% was added.

The test method is as follows.

The fluidity was determined by the oscillating flow value.
Mud material preheated at 70 ° C for 3 hours
S: Filled into R-2521 flow cone, 4G after unframed
The spread size of the mud material after the vibration was given was measured at two places, and the average value was shown.

Filling workability was evaluated by visually observing the degree of adhesion of each material to the insertion tube by automatic filling operation in the actual machine, and was evaluated as follows: o, no adhesion, small adhesion, and large adhesion X, was evaluated in three stages.

The curing time was determined by filling a pre-heated mud material into a flow cone in the same manner as in the measurement of the vibration flow value, and removing the flame from the frame.
The time taken to cure in an electric furnace maintained at 00 ° C. was measured.

The corrosion resistance is from 1550 ° C. to 1 due to rotational erosion.
1 kg of blast furnace slag at 580 ° C for 40 minutes
I went as a set. After the elapse of 40 minutes, the blast furnace slag was replaced and five sets were performed. After the test, measure the erosion dimension of the specimen,
It was indicated by an index when M8 as the product of the present invention was set to 100. The larger the value, the larger the erosion dimension.

As shown in the test results in Table 3, M8 to M11 using ethylene glycol monoethyl ether and / or diethylene glycol monoethyl ether as the solvent, which is an example of the present invention, did not adhere to the automatic filling device and had a matte gun. The supply to the tank was carried out without any problems, and the work was improved without any problems by the automatic filling device.

On the other hand, M1 to M2, M4 to M4 using solvents other than ethylene glycol monoethyl ether and / or diethylene glycol monoethyl ether.
For M7 and M12 to M14, adhesion to the automatic filling device was observed.

M8 to M11 use ethylene glycol monoethyl ether and / or diethylene glycol monoethyl ether as a solvent and use a novolak type phenol resin having a number average molecular weight within the scope of the invention of claim 2 of the present invention. is there. It shows a favorable curing rate for the filling operation of the mud, and also has excellent corrosion resistance.

Each of M1 and M2 is obtained by adding a novolak type phenol resin having a number average molecular weight of less than 601 and requires a very long time for curing. This means that the holding time of the mad gun is long.

Conversely, M12 to M14 using a novolak type phenol resin having a molecular weight exceeding 700 have a high viscosity and are inferior in automatic filling workability. M15 and M16 are somewhat difficult in that the curing time is relatively short and the material may be cured in the mud gun during standby or transition.

[0044]

[Table 1]

[0045]

[Table 2]

[0046]

[Table 3]

[0047]

According to the present invention, the use of a novolak type phenol resin as a binder and the combination of a specific solvent do not cause adhesion to an automatic filling device and improve the work by using an automatic filling device in the filling operation to a mud gun. Can be fully exhibited. In addition, by further limiting the number average molecular weight of the novolak type phenolic resin, it shows appropriate fluidity and curing speed by receiving heat from the heating device, and also has excellent corrosion resistance after filling the taphole Show the effect.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshihiro Kajiwara 1-3-1, Shinhama, Arai-machi, Takasago City, Hyogo Prefecture Within Harima Ceramics Co., Ltd. (72) Inventor Tsuneo Yamaguchi 1-3-1, Shinhama, Arai-machi, Takasago City, Hyogo Prefecture Harima Ceramics Co., Ltd.

Claims (2)

[Claims] 1. A mud material for a blast furnace taphole, characterized by containing hexamethylenetetramine and a binder composed of a novolak phenol resin dissolved in ethylene glycol monoethyl ether and / or diethylene glycol monoethyl ether. 2. The mud material for a blast furnace taphole according to claim 1, wherein the novolak type phenol resin has a number average molecular weight of 601 to 700.