JPS58181765A - Manufacture of zircon sand - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing zircon rough angle from zircon fine powder.

Zircon has excellent properties as a refractory material, but most of the naturally occurring zircon sand is 1- or less, and as it is, coarse particles essential as a refractory raw material cannot be obtained.

Conventionally, therefore, clay or a sintering agent such as MgO or CaO was added as a binder to zircon powder such as zircon sand and zircon flour obtained by crushing the zircon sand, mixed wire, formed, dried, and fired to form rough squares. , crush this
Coarse particles are obtained by dividing into two parts.

However, in the conventional method, the strength of the rough corners after drying and after firing is insufficient. Therefore, when firing in a rotary kiln or shaft kiln used for firing this type of raw material, the furnace wall and raw materials Part of it becomes powder due to friction. In order to obtain a desired particle size from rough squares, crushing and
However, due to insufficient strength, the powder was pulverized more than necessary during pulverization, resulting in a low yield of the desired coarse particles.

Furthermore, in the past, in order to impart strength to the molded product after drying, it was necessary to increase the amount of clay used as a binder by more than 10% by weight, so the zircon content was reduced accordingly. .

The present inventors have shown that adding alumina cement and/or slaked lime, which have never been used as a binder in the production of zircon clinker, has a remarkable effect on imparting strength after drying the compact and promoting sintering of rough corners. Focusing on this, they established a method for producing coarse zircon with a high yield of coarse particles and a high content of zircon.

That is, the present invention combines fine zircon powder with alumina cement and
A method for producing zircon rough square is characterized in that slaked lime is added in an amount of 0.5 to 10 couls or less, mixed, formed, dried, and then fired.

The zircon fine powder used as the aggregate in the present invention is obtained by combining naturally produced zircon sand as it is, pulverized to 100μ or less for the purpose of filling and viscosity, and zircon flour of 10% by weight or more. Good. Depending on the safety, a small amount of bauxite, andalusite, etc. may be added.

The alumina cement and slaked lime used as binders are both well-known industrial materials and can be obtained commercially. ! It should be less than wrinkles, more preferably 1 to 5 wrinkles.

All of these binders in the present invention greatly improve the strength after molding and drying due to their hydraulic properties. The strength after drying is 2.5 to 3 times that of alumina cement and 2 to 2.5 times that of slaked lime, compared to those using clay as a binder.

In addition, the roughness after phosphoric acid is 2 to 2.5 times stronger with bare alumina cement and twice as strong with slaked lime as compared to those using clay as a binder. This is thought to be due to the low liquid phase formation temperature of the substance produced by the reaction of AZ, Os or CaO in the binder with ZrO and components in the aggregate, which acts to promote sintering.

On the other hand, conventionally used clays do not have hydraulic properties and have a high liquid phase formation temperature. Therefore, the coarse particles obtained by the present invention are extremely less likely to be powdered during firing and pulverization, and the yield of the desired coarse particles is high.

The above-mentioned effects of the present invention are as follows: The binder is 10! This is noticeable when the addition amount is as small as 100% or less, and unlike conventional methods, the zircon content does not decrease when added in a large amount.

In the present invention, as described above, alumina cement and slaked lime may be used alone or in combination, but in terms of the compactness and strength of the resulting clinker, the one to which alumina cement is added has less loss on ignition. .

Using the raw materials and binder, add 3 to 7 ounces of water as usual.
Weight%, pulp waste liquid, CMC (carboxy methyl
Add a binder such as cellulose) or texturin. The binder in this case is used to provide shape retention immediately after molding, and is burned away during firing. This is different from those mentioned above, such as alumina cement and slaked lime, which remain in the clinker even after firing and add strength to the clinker.

Next, it is molded using a press, granulator, etc., sufficiently dried at about 100 to 200 C, and then fired at about 1,500 to 1,700 C to form rough squares. For this firing, in the case of industrial production, a rotary kiln, a shaft kiln, etc. are generally used.

The rough angle thus obtained is crushed and divided into pieces in order to adjust it to an arbitrary set diameter.

Next, examples of the present invention, conventional examples, and experimental examples will be shown.

Table 1 shows the chemical analysis values of the raw materials and binders used.

Table 2 shows the blending ratios on each side, the molded bodies obtained therefrom, and the physical properties of the rough corners.

Each side was cross-wired, molded, and fired under the following conditions.

Kneading: CMC was added to the aggregate in an external manner, and the mixture was kneaded using a wet pan for 1000 batches for 10 minutes.

Molding: Regular size (114 x 13
0x60m).

Drying: 110CX20hr drying.

Firing 2: Fired in a tunnel kiln at 1600G.

Note: Test method in Table 2 II Porosity/Bulk Specific Gravity... Koda R2205 Compressive Strength...JIS
Yield of R2206 coarse grains: After crushing the grains into fist-sized pieces with a hammer, crush them for a certain period of time with an impeller breaker, sieve them with a sieve, and calculate the particles with a size of 1 kg or more in weight IU. ShimaAs is clear from the results in Table 2 above, in the examples of the present invention in which alumina cement or silica silica was added as a binder, even if the amount added was less than 10-1, after drying.
Excellent compressive strength and compactness after firing. Therefore, the yield of coarse particles is high and the zircon content is high.

Experimental example 1.2 deviates from the scope of the present invention in which the amount of binder added exceeds 10 tII, and the compressive strength, compactness, and yield of coarse particles are all excellent, but the addition of binder The larger the amount, the lower the zircon content, making it impossible to fully demonstrate the characteristics of zircon as a refractory raw material.

Among the examples of the present invention, good results were obtained in nine cases using alkina cement compared to slaked lime. This is because, as is clear from the chemical composition in Table 1 of Fi, there is a large difference in the loss on ignition between the two.

On the other hand, Experimental Example 3 and the conventional example using clay as a binder were inferior to the inventive example in all tests. In addition, in Experimental Example 1, no binder was added, so there was no shape retention after drying, and it was impossible to measure anything other than the zircon content.

As described above, the method of the present invention produces zircon coarse particles from zircon fine powder by using alumina cement and slaked lime as binders to achieve strong structural strength due to its hydraulic properties and sintering action. The key is to obtain the desired coarse zircon particles in a high yield.

Further, in the present invention, the above-mentioned binder used is effective even in a small amount, so there is no need to reduce the zircon content.

Claims (1)

[Claims] Alumina cement and/or slaked lime are added to the zircon fine powder in an amount of 0.5 to 10 s by weight or less to cross wire, form,
A method for manufacturing zircon rough angle, which involves firing after drying.