JPS603035B2 - Low-temperature curing injection material composition for blast furnaces - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a monolithic refractory for injecting and repairing a furnace body, such as a blast furnace, in which the inside of the shell is lined with refractories.

Conventionally, this type of monolithic refractory is made of a granular or powdery refractory material as aggregate and an inorganic binder such as alkali silicate or phosphate, alumina cement, or an organic binder such as coal tar pitch or petroleum pitch. It has been common practice to mix these ingredients in an appropriate ratio, add water or a non-aqueous solvent as a workability imparting agent, and use the mixture by injection.

However, damage from furnace crashes continued to occur in operating blast furnaces.
When red heat or cracks occur in the steel shell, it is customary to sprinkle water on the steel shell to protect it, and since the injection of refractories is carried out during the blast furnace's wind down period, the time after the wind break is As time progresses, the temperature near the steel shell in the furnace decreases, reaching a low temperature of 80 to 90°C. Therefore, the refractory used here is required to have the property of curing within two hours due to the Yamashiro Tsubasa process, which is extremely difficult to achieve with the above-mentioned organic binder. For inorganic binders, this is possible by adding a hardening agent,
It has the disadvantage of poor springiness with the steel shell and integration with coke, and the refractory structure deteriorates.

The purpose of the present invention is to solve such problems, and to achieve [1' adhesion with steel shell, ■ retention between coke grains, {3} and good integration with coke, ■ and 80 to 90°C The objective is to obtain a monolithic refractory that can harden within two hours and exhibit high hardness. In recent years, epoxy resins, unsaturated polyester resins, alkyd resins, urea resins, melamine resins, phenolic resins,
Thermosetting synthetic resins such as furan resins have begun to be considered, but phenolic resins and furan resins with high charcoal coverage are suitable for bonding refractories with strong carbon bonds up to high temperatures.

However, furan resin is expensive and lacks stability in terms of raw materials, so phenolic resin is most suitable. There are two main types of phenolic resins: one is resol type phenolic resin (hereinafter referred to as resol type resin), which is made by converting 1 mole of phenol and 1 mole or more of formaldehyde into a resin under a basic catalyst; This is a novolak type phenol resin (hereinafter abbreviated as novolak type resin) which is made by converting 1 mole of phenol and 1 mole or less of formaldehyde into a resin under an acidic catalyst. The former is also called a one-step process phenolic resin and can complete curing at a relatively low heating temperature (80 to 15,000 ℃), while the latter is called a two-step process phenol resin and uses hexamethylenetetramine (hereinafter abbreviated as hexa) as a curing agent. By adding an appropriate amount of, curing can be completed at a slightly high heating temperature (150 to 250 qo). Therefore, from the purpose of the present invention,
Naturally, a one-step phenolic resin, that is, a resol type resin, must be used for curing within 80 to 90 hours, but as a disadvantage of resol type resins, it contains some free formaldehyde, so formaldehyde may cause irritation during work. It is not possible to avoid the negative effects on the human body caused by odor generation, and it is not possible to obtain a sufficient cured product within 2 hours. We attempted a method of activating the methylol group using an acid catalyst to accelerate curing.
However, in that case, since the reaction proceeds from room temperature, it is very difficult to obtain the convenient time of 2 hours required for the work process. As mentioned above, the use of resol type resins themselves has not been put into practical use due to the adverse effects on the human body and the difficulty of controlling the curing speed at an appropriate temperature and within an appropriate expediting time. In order to avoid the disadvantages of such resol type resins and to achieve the objectives of appropriate temperature and appropriate expediting time, the present invention has developed a two-step phenolic resin that is solid and odorless at room temperature, that is, a novolac type resin, by adding a curing agent to it. By blending an appropriate amount of powdered binder with fire-resistant aggregate, and kneading this with a slightly volatile glycol solvent such as ethylene glycol, diethylene glycol, triethylene glycol, or polyethylene glycol, it is odorless and storage stable. I was able to obtain a mixture.

However, as it is, the first objective of the present invention is 80-9
0oo, curing performance within 2 hours cannot be obtained. This requires a curing accelerator which characterizes the novelty of the present invention. That is, a solvent such as ethylene glycol at the time of kneading is used as a curing accelerator that has a storage stability of 1q hours or more at 35oo as a convenience time and 3 hours or more at 50°C, and completes curing within 2 hours at 80 to 90qo. As a curing accelerator that promotes the activation of novolak-type resins, it is compatible with resol-type resins along with oxy-containing phenols such as resorcinol, 3.5-xylenol, and bisphenol A, which are not normally used in novolac-type resins. This goal was achieved by using aromatic sulfonic acids such as para-toluene sulfonic acid, benzene sulfonic acid, and xylene sulfonic acid, which have been used in the past, but have never been used in novolak-type resins. was completed. These phenols and aromatic sulfonic acids are mixed into the glycol solvent which is the solvent for the novolac type resin of the present invention described above. The second feature of the present invention is that when a novolac type resin is used as a casting material, it exhibits a viscosity peculiar to a polymeric material. If the viscosity is made so that it can be pumped using a plunger pump, the refractory material tends to flow down inside the furnace instead of staying between the coke grains, so in order to solve this problem, The second objective of the present invention is to have a viscosity within the range of capacity that can be pumped by a rolling mill, and to improve the retention of 1 between the coke grains of the refractory material, it is necessary to add a flocculant. As flocculants for this purpose, the present inventors have used synthetic condensation type flocculants such as amine-formalin type, amine-epichlorohydrin type, and polyethyleneimine, or polyacrylamide, polyoxyethylene, and sodium polyacrylate. By using a synthetic polymerization-type coagulant, we succeeded in adjusting the particle size to a size that allows the coke to be pumped using a pressure feeder and allows the refractory material to remain between the coke particles.

That is, the composition of the Hijirimura composition for blast furnaces of the present invention, which is an amorphous refractory, is specifically composed of ○' granular or powdery refractory material.
10 parts by weight ■ 3 parts by weight of binder 7-2, which is a novolac type synthetic resin material with the addition of a curing agent, hexamethylenetetramine. Phenols and aromatic sulfonic acid (used by dissolving with glycols or higher alcohols) Curing Accelerator: 5 to 1 parts by weight [41 Solvent selected from ethylene glycol or higher alcohols]
20 to 4 parts by weight Synthetic condensation type or synthetic polymerization type flocculant (dissolved with glycols or higher alcohol) flocculant 0.7 to 3. This is a blast furnace injection material composition consisting of parts by weight of .

Here, the granular or powdery refractory material is a mixture of one or more materials such as alumina, silicic acid, lousite, carbonaceous material, clay, etc., and has a particle size configuration used in general monolithic refractories. has.

As a binder, a mixture consisting of a novolac-type phenolic resin and a hardening agent Hexa added to the resin in a range of 5 to 25% (hereinafter, % or part is a weight part or % unless otherwise specified) was used. , a powder or a liquid dissolved in an alcoholic solvent such as methanol, ethanol, or ethylene glycol, and the weight of the binder used is 7 to 2 parts per 10 parts of the refractory material. If the binder is less than 5 parts, the desired strength at low temperatures will not be achieved even if it is used in combination with a curing accelerator, which is inappropriate; if it is more than 22 parts, the refractory structure will deteriorate due to the volatile content of the binder. Since there are problems such as deterioration and high cost, preferably 7 to 2 Boto is good. Next, the curing accelerator used in the present invention is a substance that is compatible with the novolac resin and the solvent and activates the curing of the novolac type resin, that is, a substance that is compatible with formaldehyde rather than the usual reaction between phenol and formaldehyde. Resorcinol that reacts faster, 3
- Phenols such as 5-xylenol and bisphenol A, and aromatic sulfonic acids such as varatoluene sulfonic acid, benzene sulfonic acid, and xylene sulfonic acid/Compatible with borac type resin and solvent, promoting the curing performance of hexa At the same time, we use safe, odorless solvents with high boiling points and relatively high flash points, such as glycols such as ethylene glycol, diethylene glycol, and propylene glycol, as hardening accelerators that do not cause any adverse effects by remaining in the refractory after curing. For example, dissolve and use the following blending ratio.

Formulation example: Resorcinol: 15-2 parts Para-toluenesulfonic acid: 20-5 parts Ethylene glycol: 30-65 parts Since the substance and an organic acid such as para-toluene sulfonic acid are used together, the mixing ratio and the amount of solvent are not necessarily limited to the above formulation example.

When using a curing accelerator like the one in the formulation example, the desired strength cannot be obtained with less than 3 parts of the curing accelerator regardless of the amount of noporak type resin, and more than 10 parts of curing accelerator cannot be added. However, since the effect of the curing accelerator is almost the same, 5 to 1 anchor portion is appropriate except in special cases. Solvents used in the present invention include polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and glycerin, and 0- or monohydric higher alcohols with relatively high boiling points such as octyl alcohol and nonyl alcohol. An alcohol with a high flash point, which does not react with the novolak type resin, hexane, or the above-mentioned curing accelerator components, and which has good solubility is selected.

However, the solvent does not necessarily have to be the same as that used for the curing accelerator, and a different solvent may be used. If the amount of solvent added is less than 18 parts, the muddy acid becomes viscous and is not suitable. Moreover, if it exceeds 4 parts, the refractory structure will deteriorate, so preferably 20 to 4 parts is suitable. In addition, flocculants include synthetic condensation type flocculants such as amine-formalin type, amine-epichlorohydrin type, and polyethyleneimine, or synthetic polymer type flocculants such as polyacrylamide, polyoxyethylene, and sodium polyacrylate. It is an organic synthetic flocculant such as a coagulant, and is dissolved in the above-mentioned high boiling point alcoholic solvent or the like in the following blending ratio.

Blend example polyacrylamide 0.1-2.
Foundation ethylene glycol Satoshi ~99. $ parts However, the above blending ratio varies depending on the selection of the flocculant, and is not limited to the above blending example.

When a flocculant like the one in the formulation example is used, if it is less than 0.5%, the desired state of refractories cannot be obtained;
．． If it exceeds 2%, the viscosity of the refractory material will become too high.
The amount of flocculant added is 0 as there will be problems with the pumpability of the refractory material.
．． 7 to 3.0% is appropriate. Below are examples of experiments that determined the gist of this developed sardine, followed by specific examples.

Experimental example 1 (for determining the appropriate amount of resin) From the above experimental example, when the amount of /borac type phenol resin (containing hexane) added was 5 parts, the adhesion strength to the iron plate was insufficient.
It is necessary to add 7 parts or more in order to maintain the adhesion to the steel shell as intended by the present invention.

Experimental example 2 (for determining the amount of curing accelerator added) Note) * Resorcinol and para-toluenesulfonic acid dissolved in ethylene glycol According to the above experimental example 2, the amount of curing accelerator was 3
If it is less than 90% water, it will not be possible to obtain a cured product with 90% water, which is the objective of the present invention.
1 part or more of the curing accelerator is required (however, if the curing accelerator is 1 part or more, the curing will almost reach equilibrium).

Experimental example 3 (for determining the appropriate amount of flocculant added) Note) *1 Same as experimental example 2 *2 Polyacrylamide; ethylene glycol; 1:
200 (wt) *3 △Retention rate between coke grains=X±ball xloo In formula A: Weight of refractory stuck between coke grains (B of
: Weight of refractory flowing down without stopping between coke grains (Examples of the present invention are shown next to k.

Examples Using alumina and carbonaceous raw materials also exhibited the same problems as when using lostone raw materials, so they will also be described.

(*2) ○: Good △: Average ×: Poor

Claims (1)

[Scope of Claims] 1. A binder made of a novolak type phenolic resin prepared by mixing hexamethylenetetramine with a refractory raw material whose particle size has been adjusted, and a monovalent phenol having a divalent phenol, a trivalent phenol, and an alkyl group substituted at the meta position. One or more of alkylphenols and bisphenols A and one or more aromatic sulfonic acids
A low-temperature hardening blast furnace characterized in that it is made by adding an accelerator consisting of at least one species, a solvent selected from polyhydric alcohols and higher alcohols, and an organic flocculant that is dissolved or compatible with the solvent. Press-fit material composition. 2. For 100 parts by weight of the refractory raw material whose particle size has been adjusted, 7 to 20 parts by weight of a binder consisting of a novolak type phenolic resin mixed with hexamethylenetetramine, divalent phenol, trivalent phenol, and an alkyl group substituted at the meta position. 5 to 10 parts by weight of an accelerator consisting of one or more monohydric alkylphenols and bisphenols A and one or more aromatic sulfonic acids selected from polyhydric alcohols and higher alcohols. 20 to 40 parts by weight of the solvent,
The organic flocculant that dissolves or is compatible with the same solvent is 0.7 to 3.
The low-temperature hardening blast furnace injection material composition according to claim 1, characterized in that the content is 0 parts by weight.