JPH10287475A - Prepared unshaped refractories containing fibers having specific length and for used for forceful feeding with pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide prepared unshaped refractories capable of preventing segregation caused on the forceful feeding of prepared unshaped refractories with a pump and suitable for the forceful feeding of the prepared unshaped refractories with the pump to obtain a uniform applied product. SOLUTION: This prepared unshaped refractories contain organic fibers having a length of A to B (A is the diameter of the granules at an accumulated weight of 50% from the maximum granule diameter of the unshaped raw material having granule diameters of <10 mm; B is a length obtained by adding 3 mm to the maximum granule diameter of the unshaped raw material having granule diameters of <10 mm) and having a diameter of <=100 μm in an amount of 0.05-0.5 wt.% per 100 wt.% of the unshaped raw material having the granule diameter of <10 mm in the prepared unshaped refractories.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an amorphous refractory used for a molten metal container, a molten metal processing apparatus, a cement kiln, an incinerator and the like, which is sufficiently mixed with water or other kneading liquid by a mixer in advance. The present invention relates to an amorphous refractory which is kneaded and pumped.

[0002]

2. Description of the Related Art Conventionally, as a method of transporting kneaded amorphous refractories, a method of transporting the refractories in a container such as a bucket,
There is a method of transporting by belt conveyor, etc., but the pumping method by pump is a method that can be poured, press-fitted and sprayed in a process that is continuous with pumping, and is used as a transport method with high work efficiency. I have. For example, Japanese Patent Application Laid-Open No. 54-90211 discloses press-fitting by pumping, and Japanese Patent Application Laid-Open No. 54-60505 discloses a wet spraying method by pumping.

[0003] However, the pumping method using this pump is an effective method for transporting irregular refractories with extremely high working efficiency, but the irregular refractories are subjected to segregation (separation between coarse particles and fine particles. The same). Specifically, coarse particles are separated into the central part and fine particles are separated outward in the transport pipe, and due to such segregation, it is determined that the transported material is initially transported by pumping. The particle size composition, and thus the composition, may vary in the conveyed product at all times. This is an unfavorable phenomenon because the work is performed in a state where segregation has occurred.

[0004] In recent years, in order to achieve consolidation of facilities and reduction of labor costs, a construction method in which irregular-shaped refractories are kneaded in one place and pumped from there to a site where the refractory is used has been considered. However, for that purpose, it is necessary to prevent segregation of the amorphous refractory by pumping.
For example, in a construction in which an amorphous refractory is pumped over a long distance as in the construction of a cement kiln or an incinerator, segregation tends to increase.

Therefore, as a method of preventing segregation of amorphous refractories, generally, a thickener is added to increase the viscosity.

[0006]

However, this method of increasing the viscosity reduces the pumpability of the amorphous refractory, and is not preferable as a method applied to the amorphous refractory for pumping. It is.

[0007] The present invention is to provide an amorphous refractory suitable for pumping in order to prevent segregation occurring during pumping of irregular shaped refractories and to obtain a uniform construction.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide an amorphous refractory having 100% by weight of an amorphous material having a particle size of less than 10 mm.
On the other hand, the length of the organic fiber to be externally added is 0.05 to 0.5% by weight, and the length of the organic fiber is A to B (A is a particle diameter having a cumulative weight of 50% from the maximum particle diameter of the amorphous material having a particle diameter of less than 10 mm , B is a length obtained by adding 3 mm to the maximum particle size of the amorphous raw material having a particle diameter of less than 10 mm), and the irregular shape for pumping containing a fiber having a specific length of 100 μm or less. The solution is to get a refractory.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to an amorphous refractory used for a molten metal container, a molten metal processing apparatus, a cement kiln, an incinerator and the like, which is sufficiently kneaded with water or the like in advance by a mixer and pumped. It can be applied to irregular refractories.

As a method of adding organic fibers to an amorphous refractory, there is known a method of forming air holes with organic fibers to enhance the drying property, but the objects and effects of the present invention are different. Of course, the drying property can be enhanced by adding the organic fiber of the present invention. However, the present invention has strictly limited the length of the organic fiber in order to prevent segregation which occurs particularly during pumping of an amorphous refractory and to obtain a uniform construction.

As the material of the organic fiber, acryl, acetate, aramid, nylon, viscose rayon, vinylidene, vinylon, polyurethane, polyester, polyethylene, polyvinyl chloride, polypropylene, polynosic and the like are used. In particular, a material which has good wettability with water or other kneading liquid used for the amorphous refractory and is easily dispersed is preferable. It is also possible to improve the wettability by subjecting the fibers to a surface treatment.

[0012] The amount of the organic fiber added is 0.1 to 100% by weight of the amorphous raw material having a particle size of less than 10 mm in the amorphous refractory.
0.5 to 0.5% by weight. If the addition amount is less than 0.05% by weight, the effect of preventing segregation of the amorphous refractory during pumping is small. On the other hand, if the addition amount is more than 0.5% by weight, the amount of added water for obtaining a pumpable consistency increases, and the characteristics such as the corrosion resistance as an amorphous refractory deteriorate. Of course, when the porosity is intentionally increased as in the case of a heat insulating material, the amount of organic fibers to be added may be increased beyond the range specified in the present invention.

[0013] The length of the organic fiber is defined as A, the particle size of which the cumulative weight is 50% from the maximum particle size of the amorphous material having a particle size of less than 10 mm, and 3 mm as the maximum particle size of the amorphous material having a particle size of less than 10 mm.
Is set to B, and the length is added to the range of AB. A specific method for obtaining A is, for example, 0.5
The particle size distribution was measured with a sieve at intervals of ~ 1 mm, and the integrated weight from the maximum particle size was plotted on the x-axis, and the particle size (interval of the sieve) was plotted on the y-axis. The particle size A, which is the value on the y-axis at the point where the weight becomes 50%, is read.
Incidentally, the length of the organic fiber added when pumping an amorphous refractory having a maximum particle size of 5 mm and a particle size of 1.2 mm with a cumulative weight of 50% from the maximum particle size is 1.2 to 8 mm. Be within range.

The reason why the length of the organic fiber is defined as described above is that if the organic fiber is shorter than A, the effect of preventing segregation of the amorphous refractory during pumping is small. On the other hand, if the length is longer than B, the amount of water added to obtain a pumpable pumping consistency increases, and characteristics such as corrosion resistance as an amorphous refractory deteriorate. When the length of the organic fiber is defined in this way, the reason why the segregation of the amorphous refractory during pumping can be prevented is that the organic fiber directly acts because the particle diameter is 10 m.
50% of the cumulative weight from the maximum particle size of the amorphous material less than m
This is the movement of the coarse-grained portion to the extent that if the organic fiber is too short than the minimum diameter of the coarse-grained portion (defined organic fiber length A), there is no effect of adding the organic fiber, and 3 mm is added to the maximum particle size. When the organic fibers are longer than the length (specified organic fiber length B), it is considered that the fibers are entangled (entangled) and the pumpability is reduced. That is, in defining the length of the organic fiber to be added, the reason for excluding coarse particles having a particle size of 10 mm or more is that the direct effect on the movement of the coarse particles is small, and such coarse particles are not used for other amorphous raw materials. And a discontinuous distribution.

The diameter of the organic fiber is set to 100 μm or less. This is because when the diameter of the organic fiber is larger than 100 μm, the pumping property is reduced. It is considered that this is because when the diameter of the organic fiber increases, the elasticity of the fiber increases and the deformability decreases. Although the lower limit of the diameter is not particularly limited, it is usually preferably 10 μm or more from the viewpoint of the fiber production cost.

As the amorphous raw material used in the present invention, refractory raw materials used for general amorphous refractories and additives such as a binder and a deflocculant can be used within a practicable range.
For example, refractory raw materials include electrofused or sintered alumina, calcined alumina, bauxite, electrofused or synthetic mullite, sillimanite, andalusite, kyanite, ban shale, chamotte, rholite, silica, fused silica, Fused or sintered magnesia, fused or sintered spinel, fused or sintered zirconia, zircon, chromite, fused or sintered magnesia lime, fused zirconium armlite, fused alumina zirconia, titania, silicon carbide , Silicon nitride,
Natural or artificial graphite, petroleum coke, pitch coke,
Anthracite, carbon black, amorphous carbon such as pitch, etc.
It is not particularly limited as long as it is generally used, and one or a combination of two or more of these may be used according to the use location and use conditions of the amorphous refractory.

The refractory raw material can be used as needed by separately adding furnace waste material or brick crushed particles as coarse particles having a particle size of 10 to 40 mm in a range of 10 to 50% by weight, if necessary.

As the binder, for example, cement such as alumina cement, magnesia-silica hydraulic composition,
Hydraulic transition alumina, alkali silicate, phosphate, clay,
One or more kinds of colloid particles can be used.

Examples of peptizers include condensed phosphoric acid, polyacrylic acid, polycarboxylic acid, phosphonic acid, humic acid,
One or more of alkyl sulfonic acid, aromatic sulfonic acid and the like, or salts thereof can be used.

[0020]

EXAMPLES Examples and comparative examples according to the present invention are shown in Table 1, Table 2, Table 3, Table 4, Table 5 and Table 6.

The examples and comparative examples specified in the present invention are applied to the following refractory raw materials, binders, deflocculants,
Coarse grains and organic fibers were used.

As the refractory raw material, sintered alumina having a purity of 99.7 wt%, purity of 99.6 wt%, and an average particle diameter of 1.5 μm
Calcined alumina and a purity of 96.0 wt% average particle size 0.2
8 μm evaporated silica was used.

5 wt% of alumina cement SECAR71 manufactured by Lafarge is used as a binder, and sodium polyacrylate is used as a peptizer at 0.1 wt%. lwt% was used.

The coarse particles have a sieved particle size of 20.
Sintered alumina with a purity of 99.5 wt% in the range of ３０30 mm was used.

As the organic fibers, those having the length and diameter shown in the table made of vinylon were used. It should be noted that what is shown here is not limited to the examples, and it is possible to obtain the same effect by using a refractory raw material, a binder, and a deflocculant which are usually used as amorphous raw materials. .

The particle size of 50% of the cumulative weight from the maximum particle size is
It is a value interpolated from the measured value of the particle size distribution measured using a sieve, and the average particle size of the fine powder is a value measured by a laser diffraction method.

In the table, the amounts of coarse particles, organic fibers and water added are indicated by an outer number (ten) with respect to the other solid content of 100% by weight.

The segregation was conducted by kneading 1200 kg of the amorphous refractories shown in the table with a mixer, and using an AP-10 swing valve pump manufactured by Allentown to have an inner diameter of 0.051 m (2 inches) and a length of 30 kg.
For irregular shaped refractories sampled by pumping through a 48 m (100 ft) heavy duty hose,
Evaluation was made by comparing the ratio of coarse particles remaining in a 2 mm sieve in accordance with "JIS A1112 Test Method for Washing and Analyzing Concrete that has not yet set). Sampling is performed by adding 100 kg, 200 kg
kg, 500 kg, and 800 kg were discharged.

Further, as shown in FIG. 1, a nozzle is installed at a discharge port of a heavy duty hose, and an irregular refractory conveyed in the center of the heavy duty hose and an irregular refractory conveyed in the outer periphery of the heavy duty hose. The sample was separated and sampled, and the segregation at the cross section of the heavy duty hose was also evaluated.

For the evaluation of segregation, the proportion of coarse particles remaining in a 2 mm sieve of the amorphous refractories before pumping was A, and the irregular refractories sampled from the center and the outer periphery of the heavy duty hose were mixed again. The ratio of coarse particles that remained in the 2 mm sieve for the sample (that is, the sample that was not separated from the central portion and the outer peripheral portion) was changed to B, and the irregular refractory sampled from the central portion of the heavy duty hose was changed to a 2 mm sieve. The ratio of retained coarse particles is C, 2 mm for irregular refractories sampled from the outer periphery of heavy duty hose
The ratio of coarse particles remaining in the sieve is D, the degree of segregation of the amorphous refractory at the time of kneading and at the time of discharge is compared by A and B, and the center and outer periphery of the heavy duty hose are compared by C and D The degree of segregation of the amorphous refractory with the part was determined. The evaluation items of the segregation shown in the table are “| DA− / A ≦ 0.2” as a comparison between the time of kneading and the time of discharge. ”Mark,“ | D-
“A | / A> 0.2” is marked with “x” for those with large segregation. In addition, as a comparison between the center portion and the outer peripheral portion of the heavy duty hose, "| CD
| /D≦0.2 ”and those for which the segregation was judged to be sufficiently small are marked with“ 〇 ”and“ | CD− / D> 0.
2 ”and those with large segregation are marked with“ x ”.

The items of pumping shown in the table are described as "OK" if pumping was possible under the above conditions and "impossible" if pumping was not possible. I have.

[Table 1] Table 1 shows that the maximum particle size of the amorphous material is 5 mm, the particle size (A) of 50% of the cumulative weight from the maximum particle size is 1.2 mm, and the length of the organic fiber is 4 mm within the range specified in the present invention. , Diameter 20
This is an example in which the amount is fixed at μm and the amount of addition is changed.

Examples 1 to 4 are examples in which the amount of the organic fiber added was changed within the range specified in the present invention (0.05 to 0.5% by weight). It was very small.

In Comparative Examples 1 and 2, since the amount of organic fiber added was less than the specified range of the present invention (0.05 to 0.5% by weight), large segregation occurred during pumping. In Comparative Example 3, pumping was impossible because the added amount of the organic fiber was larger than the specified range (0.05 to 0.5% by weight) of the present invention.

[0034]

[Table 2] Table 2 shows that the maximum particle size of the amorphous raw material is 5 mm, the particle size (A) of 50% of the cumulative weight from the maximum particle size is 1.2 mm, and the diameter of the organic fiber is 20 μm within the specified range, and the amount added is 20 μm. +0.
This is an example in which the length is changed to be constant at 2% by weight.

In Examples 5 to 8, the length of the organic fiber was set to 1.2.
In each of the examples, the segregation generated at the time of pumping was very small.

In Comparative Example 4, since the length of the organic fiber was shorter than the specified range (1.2 to 8 mm) of the present invention, the prevention of segregation was not satisfactory.

In Comparative Example 5, pumping was impossible because the length of the organic fiber was longer than the specified range (1.2 to 8 mm) of the present invention.

[0038]

[Table 3] Table 3 shows that the maximum particle size of the amorphous raw material is 8 mm, the particle size (A) at an integrated weight of 50% from the maximum particle size is 1.8 mm, and the diameter of the organic fiber is 20 μm within the specified range, and the amount added is 20 μm. +0.
This is an example in which the length is changed to be constant at 2% by weight.

In Examples 9 to 12, the length of the organic fiber was 1.
In this case, the segregation generated during pumping was very small.

In Comparative Example 6, the prevention of segregation was not satisfactory because the length of the organic fiber was shorter than the specified range (1.8 to 11 mm) of the present invention.

In Comparative Example 7, pumping was impossible because the length of the organic fiber was longer than the specified range (1.8 to 11 mm) of the present invention.

[0042]

[Table 4] Table 4 shows that the maximum particle size of the amorphous raw material is 3 mm, the particle size (A) of 50% of the integrated weight from the maximum particle size is 1.1 mm, and the diameter of the organic fiber is 20 μm within the specified range, and the amount added is 20 μm. +0.
This is an example in which the length is changed to be constant at 2% by weight.

Examples 13 to 15 are examples in which the length of the organic fiber was set within the specified range of 1.1 to 6 mm, and the segregation generated at the time of pumping was very small.

In Comparative Example 8, since the length of the organic fiber was shorter than the specified range (1.1 to 6 mm) of the present invention, the prevention of segregation was not satisfactory.

In Comparative Example 9, pumping was impossible because the length of the organic fiber was longer than the specified range (1.1 to 6 mm) of the present invention.

[0046]

[Table 5] Table 5 shows that coarse particles having a particle size of 20 to 30 mm are added as an irregular raw material in an external manner by + 30% by weight, the maximum particle size of the irregular raw material excluding the coarse particles is 8 mm, and the cumulative weight from the maximum particle size is 50%.
This is an example in which the particle size (A) is 1.8 mm, the diameter of the organic fiber is 20 μm within a specified range, the addition amount is fixed at + 0.2% by weight, and the length is changed.

Examples 16 to 19 were examples in which the length of the organic fibers was within the specified range of 1.8 to 11 mm, and the segregation generated at the time of pumping was very small.

In Comparative Example 10, since the length of the organic fiber was shorter than the specified range (1.8 to 11 mm) of the present invention, the prevention of segregation was not satisfactory.

In Comparative Example 11, pumping was impossible because the length of the organic fiber was longer than the specified range (1.8 to 11 mm) of the present invention.

[0050]

[Table 6] Table 6 shows that the maximum particle size of the amorphous raw material is 5 mm, the particle size (A) of 50% of the cumulative weight from the maximum particle size is 1.2 mm, and the length of the organic fiber is within the range specified in the present invention. This is an example of a case where the addition amount is constant at an outer diameter of + 0.2% by weight at 4 mm and the diameter is changed.

Examples 20 to 22 are examples in which the diameter of the organic fiber was changed within the specified range of the present invention (100 μm or less), and in each case, segregation generated during pumping was very small. .

In Comparative Example 12, pumping was impossible because the diameter of the organic fiber was larger than the specified range (100 μm or less) of the present invention.

[0053]

By adding an organic fiber within the regulation range of the present invention, segregation of coarse particles and fine powder when pumping amorphous refractories can be minimized. The irregular refractory for pumping of the present invention was used in molten metal containers, molten metal processing equipment, cement kilns, incinerators, etc., but segregation (coarse and fine particles) generated when pumping irregular shaped refractory was carried out. ), A uniform construction can be obtained, and the corrosion resistance, spalling resistance and other refractory property strengths can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a heavy-duty hose used for evaluating segregation of an amorphous refractory.

FIG. 2 is a cross-sectional view of the heavy-duty hose discharge port shown in FIG.

[Explanation of symbols]

 1 Heavy Duty Hose 2 Irregular Refractory Inside / Outside Separation Nozzle 3 Outer Refractory Outlet 4 Central Refractory Outlet

Claims (1)

[Claims] 1. 0.05 to 0.5% by weight based on 100% by weight of an amorphous material having a particle size of less than 10 mm in an amorphous refractory.
The length of the organic fiber to be externally added is A to B (A is a particle size of 10
The cumulative weight from the maximum particle size of the amorphous material less than 50 mm is 50
%, B is a length obtained by adding 3 mm to the maximum particle size of the amorphous raw material having a particle size of less than 10 mm), and the fiber contains a fiber having a specific length of 100 μm or less. Irregular refractories for pumping.