JPS59141452A - Manufacture of calcium silicate molded body - 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 a calcium silicate molded body, and more particularly to a method for producing a calcium silicate molded body using a new silicic acid raw material that has not been previously used in the production of this type of molded body.

In the production of calcium silicate molded bodies, attempts have already been made to use rice husk ash (residue from burning rice husks) as a silicate raw material, and the main component of this rice husk ash is S'+.02. This has also been confirmed. However, when this rice husk ash is used as a silicate raw material, the formation is extremely unstable when trying to obtain a molded body consisting of thonodolite crystals as calcium silicate crystals, and even when formed, the physical properties vary considerably. However, it is extremely difficult to obtain a molded article that is practically satisfactory and has certain physical properties.

The present inventor has been researching methods for using rice husk ash as a raw material for silicate, but in this research, he came up with a completely new idea of whether it is possible to use charcoal or a substance derived from charcoal as a raw material for silicate. Based on this idea, I continued my research and discovered that when using burnt charcoal as a silicate raw material, the problems associated with using rice husk ash can be overcome. The inventors discovered that the crystal formation was extremely easy and stable, and that it was possible to easily produce molded bodies made of sawnodorite crystals with stable physical properties, leading to the completion of the present invention. In the invention, a raw material slurry obtained by mixing a silicic acid raw material mainly composed of burnt charcoal and a lime raw material with water such that the amount of water to solid content is 5 times or more by weight is heated and stirred under pressure. This invention relates to a method for producing a calcium silicate molded body, which is characterized by carrying out a hydrothermal synthesis reaction to form a slurry of calcium silicate crystals containing thonodolite crystals as a main component, and then molding and drying the slurry.

The present invention has the following features. That is, (2) using charcoal, which has never been used as a raw material for producing this type of calcium silicate molded body, as a raw material, and by firing this charcoal, it is extremely easy to produce a calcium silicate molded body. It has the characteristics that it does not have the disadvantage of not being able to obtain a stable molded product of constant quality under certain conditions, which occurs when using 09 rice husk as a raw material as it is. ing.

In the present invention, the fired Kush charcoal used as a silicic acid raw material is a product obtained by firing Kush charcoal in an atmosphere of about 300 to 800°C to remove the carbon content in the Kush charcoal. The carbon content of the fuel may ignite and the temperature may rise to around 1000°C. The fired product of comb charcoal can also be used as a powder of 100 μm or less. The components of this fired product are SiO2 of 85% by weight or more, residual carbon content of about 0 to 5% by weight, and other components of about 0 to 10% by weight.

Kun charcoal used as raw material for kun charcoal fired products is 1.
It is manufactured by dry distilling rice husk, wheat, rice straw, wild grass, fallen leaves, etc. Its composition is usually SiO2: 30
~80% by weight, C: 20-50% by weight, 1I20:0
-10% by weight, and others: about 0-10% by weight.

In principle, the conditions of conventional manufacturing methods can be applied when implementing the Non-Invention Law. That is, all the conventional conditions can be effectively applied, except that the above-mentioned specific raw material is used as the main component as the silicic acid raw material, and the amount of water is at least 5 times the solid content of the raw material slurry. A more detailed explanation is as follows.

As the silicic acid raw material, only the fired comb charcoal product can be used, but if necessary, it can also be used in combination with other ordinary silicic acid raw materials. Even when used together, the main ingredient must be a charcoal-fired product. As other silicic acid raw materials used at this time, any of those conventionally used in the production of this type of calcium silicate molded body can be effectively used. For example, silica stone, silica sand, etc. can be used as crystalline silicic acid raw materials, Examples of raw materials include silica gel, silica flower 1 white carbon, diatomaceous earth, and the like.

As the lime raw material, any material that has been conventionally used can be used, such as quicklime 1 slaked lime, carbide slag, etc., and the purpose is to obtain a lightweight body with a density of about 0.1 f/d as a molded object. In this case, it is preferable to use milk of lime having a sedimentation volume of 51 or more. The sedimentation volume of milk of lime refers to the settling volume of lime particles after 50 ml of lime milk with a water to lime solids ratio of 120 times is allowed to stand for 20 minutes in a female silicate with a diameter of 1°3G and a volume of 50 d or more. The settled volume is m
This is indicated by l. This lime raw material is mixed with a silicic acid raw material and water to prepare a raw material slurry. The amount of water at this time is at least 5 times the solid content of the raw material slurry,
When trying to obtain the above-mentioned lightweight body, the weight is preferably 15 times or more. Silicic acid raw material, lime raw material and (7) EJL, ratio is CaO
/SiO2 is approximately 0.90=1.15. Inert additives may be added to this raw material slurry in the subsequent hydrothermal synthesis reaction, and inorganic fibers such as asbestos, rock wool, etc. can be exemplified as additives at this time.

The raw material slurry thus prepared is then subjected to a hydrothermal synthesis reaction while being stirred. The reaction conditions at this time were 8 kq/C
This reaction is carried out under a saturated steam pressure of d or more, preferably IO#/d or more, and an aqueous slurry of secondary particles of calcium silicate crystals containing thonodolite crystals as a main component is obtained. Various additives may be added to the aqueous slurry as necessary. In this case, additives that have been used in the production of calcium silicate molded bodies can be used in a wide range of ways, such as fibers, clays, and t-ment materials, and more specifically asbestos, rock, etc. Specific examples include inorganic fibers such as cotton, glass fiber, and carbon fiber, organic fibers such as various synthetic fibers, clays such as kaolin and bentonite, gypsum, Portland cement, alumina cement, and other various cements. This can be exemplified as The aqueous slurry can be molded and dried according to a conventional method to obtain the desired molded product.

The calcium silicate molded body obtained by the method of the present invention and whose main component is sheeted dry crystal has almost the same physical properties as the calcium silicate molded body whose main component is sheeted dried crystal produced by the conventional method. .

EXAMPLES The present invention will be specifically described below with reference to Examples. However, in the following examples, "part" or "%" indicates weight part or weight %, which is not particularly explained.1The bending strength is based on JIS A.
It was measured according to the method of No. 9510.

Example 1 The sedimentation volume of milk of lime obtained by slaking 42.24 parts of quicklime (CaO 95.0%) in 507 parts of 80°C warm water was 4.8.
It was Ko. The average particle size is 1, obtained by baking the above lime milk and rice husk charcoal in an atmosphere of 500°C for 3 hours and then pulverizing it.
0pm (D powder (Sin, 95.3%, C1.03%
) Disperse 45.26 parts with 10 times the weight of water in a water mixer for 2 minutes. to obtain a raw material slurry.1 This was brought to a saturated steam pressure of 12 to 9/CI.
A temperature of 191°C and rotation speed of 102 in an autocooker.
The slurry was stirred while rotating the stirring blade at r, door, and nr, and a hydrothermal synthesis reaction was carried out for 5 hours to obtain a slurry.

The slurry obtained above was dried at 100°C for 24 hours and S
X-ray diffraction analysis revealed the presence of thonodorite crystals.Next, 7 parts of glass fiber and 3 parts of poldrasitocemecite were added as additives to 90 parts (solid content) of the slurry obtained above, and the mixture was press-molded. The mixture was dried at 100° C. for 24 hours to obtain a molded article.

The physical properties of the obtained molded product were as shown in Table 1.

Table 1 Example 2 25.34 parts of quicklime (CtlO95.0%) was heated at 80°C.
The sedimentation volume of the lime milk obtained by slaked in 304 parts of hot water and dispersed in water using a homomixer was 15.2 txt. To the above lime milk, a slurry obtained by dispersing 27.16 parts of the same rice husk charcoal burnt powder as in Example 1 with 10 times the weight of water for 2 minutes in a ho-shichi-3ter was added, and further water was added. A raw material slurry was obtained by mixing the total amount of water to be 40 times the weight of the solid content, and this was heated in an autoclave at a saturated steam pressure of 12#/cm and a temperature of 191°C at a rotation speed of L O7r.
The slurry was stirred while rotating the stirring blade at a door 9m, and a hydrothermal synthesis reaction was carried out for 5 hours to obtain a slurry.

The slurry obtained above was dried at 100°C for 24 hours and
Linear diffraction analysis revealed that it was a thonodorite crystal.

Next, 7 parts of glass fiber and 3 parts of Portland cement were added as additives to 90 parts (solid content) of the slurry obtained above, and the mixture was press-molded and dried at 100° C. for 24 hours to obtain a molded product.

The physical properties of the obtained molded product were as shown in Table 2.

Table 2 Example 3 84.48 parts of quicklime (Ca095.0%) was added to 80
The sedimentation volume of the milk of lime obtained by slaking in 1014 parts of warm water at °C was 4.7 g/. Powder with an average particle size of 8 μm (510295, 1%, C1,
Add the slurry obtained by fractionating 90.52 parts (51%) with 10 times the weight of water in a water mixer for 2 minutes, and then add more water to make the total water amount 12 times the weight of the solid content. to obtain a raw material slurry.
/dS temperature 191'C and rotation speed 1 in an autoclave.
The mixture was stirred at 107 r and 9 m while rotating the stirring blade, and a hydrothermal synthesis reaction was carried out for 5 hours to obtain a slurry.

The slurry obtained above was dried at 100°C for 24 hours,
When analyzed by X-ray diffraction, thonodolite crystal jets were observed.

Next, 7 parts of glass fiber and 3 parts of Portland cement were added as additives to 90 parts (solid content) of the slurry obtained above, and the mixture was press-molded and dried at 100° C. for 24 hours to obtain a molded body.

The physical properties of the obtained molded product were as shown in Table 3.

Table 3 Example 4 42.47 parts of quicklime (Ca095.Q%) was slaked in 510 parts of water at 80°C and dispersed in water using a hot water heater.The sedimentation volume of milk of lime was 16. It was .2gt. Add the above lime milk to the rice husk comb and charcoal fired powder 2 as in Example 1.
7.02 parts of silica powder with an average particle size of 7.3 μm (5 in.
297.7%) was added, and water was further added so that the total amount of water was 24 times the solid content to obtain a raw material slurry.
Rotational speed 138 r in an autoclave at a temperature of 191"C
The mixture was stirred with a stirring blade rotating at a door of 1 m, and a hydrothermal synthesis reaction was carried out for 5 hours to obtain a slurry.

The slurry obtained above was dried with ioo'c for 24 hours,
X-ray diffraction analysis revealed thonodolite crystals and a small amount of tobel heptalite crystals.

Next, 7 parts of glass fiber and 3 parts of Portland cement were added as additives to 90 parts (solid content) of the slurry obtained above, and the mixture was press-molded and dried at +00°C for 24 hours to form a gold-tin molded body.

The physical properties of the obtained molded product were as shown in Table 4.

(Table 4 C and above) Procedural amendment (own ship July 27, 1980 1 Director of the Japan Patent Office Kazuo Wakasugi 1, Indication of the case 1988 Patent Application No. 15856 2. i Akio
Name, acidity 1. 1. Molded object. Manufacturing process 3, relationship with the case of the person making the amendment Patent applicant (6521) Patent attorney Eiji Saegusa 5 Date of amendment order 8 Contents of the amendment As attached to the attached sheet Contents of the amendment (1) In the description We will correct the description in the errata table below.

C and above) −2=

Claims (1)

[Claims] ■ A raw material slurry obtained by mixing a silicic acid raw material mainly composed of burnt charcoal and a lime raw material with water so that the amount of water relative to the solid content is 5 times or more by weight is heated and stirred with a pressurizer. 1. A method for producing a calcium silicate molded article, which comprises carrying out a hydrothermal synthesis reaction to obtain a slurry of calcium silicate crystals containing thonodolite crystals as a main component, and then molding and drying the slurry.