JP2002338327A - Manufacturing method of humidity control building materials - Google Patents

Abstract

(57) [Summary] The present invention provides a method for producing a humidity control material that can not only eliminate the instability of raw material collection up to now, but also increase the material strength by relatively simple means. It is intended to provide. SOLUTION: Blast furnace slag fine powder is 10 to 90 mass.
%, SiO ₂ content is 50 mass% or more, and the average particle diameter is 100 μm or less.
s%, a mixed raw material containing 1 to 25 mass% of an alkaline inorganic material is kneaded with water, and the temperature of the atmosphere is 0 to 2%.
Curing is performed at 60 ° C. and a pressure of atmospheric pressure to 2.5 MPa.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a humidity control building material, and more particularly to a technique for producing a useful humidity control building material by effectively utilizing blast furnace slag fine powder secondary to a steel mill. About.

[0002]

2. Description of the Related Art In recent years, high airtightness of buildings has been pursued in order to save energy and improve living environment, and development of new building materials and technologies for improving building structures has been promoted. However, the high airtightness of a building, on the other hand, increases the dew condensation on the surface of indoor building materials, which is a cause of deterioration in indoor habitability and durability of the building. In addition, moisture generated by condensation promotes the generation of molds and mites, and there is a concern that those substances may adversely affect the human body.

As one of the countermeasures, it is conceivable to control the indoor atmosphere by indoor air conditioning, but the cost of electric power used as power for air conditioning is relatively high. For this reason, indoor air conditioning is not used in a room where there are no people, and there is also a problem of environmental deterioration due to heat radiation to the outside, and therefore, it cannot be said that it is an optimal measure.

[0004] Therefore, there is a demand for a technique for adjusting the humidity in a room without using a power to prevent deterioration of a living environment. Due to such needs, development of a humidity control building material has been actively pursued. Here, humidity control refers to the function of sucking moisture into the material in a humid environment, and exhaling moisture from the inside in a dry environment to realize a comfortable humidity environment. It refers to itself having this humidity control action. In addition, this humidity control building material is used as an interior material of a house, an underfloor material, a ceiling material, a wall material, and the like in the form of various types of tiles, panels, boards, bricks, blocks, slab concrete, and the like.

[0005] The most common method for producing such a humidity control building material is to mix charcoal or diatomaceous earth having a large number of fine pores with another material to form the material. For example, see JP-A-11-17
No. 1662 discloses a technique for manufacturing a heat insulating structure using porous coal and inorganic mineral powder as raw materials.
We propose a new building material with air permeability, air intake, odor absorption, moisture absorption, etc. by the action of non-combustible porous coal. Japanese Patent Application Laid-Open No. 4-354514 discloses a non-firing method in which Wakkanai (Hokkaido's place name) diatomaceous earth is blended with a ceramic material and formed into an arbitrary shape and fired, or the Wakkanai diatomaceous earth is combined with other materials as a filler. It discloses a functional building material. Further, JP-A-10-2044 and JP-A-11-315586 disclose a volcanic pumice layer, a diatomaceous earth, a humidity control raw material such as zeolite, and a glassy component such as clay and feldspar, and the like, after molding. It discloses a technique of firing to make a humidity control building material. In addition, JP-A-8-144
No. 387 discloses mixing allophane or imogolite,
It discloses a technique of forming into a humidity control building material.

[0006]

However, the heat insulating structure described in Japanese Patent Application Laid-Open No. 11-171662 has hygroscopicity but cannot secure the strength as a structure.
It was necessary to use it in a state where it was housed in a mold. In addition, as the raw material, the non-combustible carbide to be carbonized, food production residue, rice hulls, pruned branches, the original form of flammable substances of animals and plants, or those shaped into the desired particle size, are mentioned. It is very difficult to stably and surely pick up things. For this reason, the raw material changes every time it is manufactured, and it has been very difficult to maintain the heat insulating effect and the moisture absorbing effect of the heat insulating structure, which is the final product, at a certain level or higher.

[0007] The humidity control building material disclosed in Japanese Patent Application Laid-Open No. 4-354514 is a building material mainly composed of a material having an excellent humidity control property, such as Wakkanai diatomaceous earth, but it is costly to use it alone. In addition, when mixed with other binders to form a building material, there remains a problem that the humidity control effect is reduced in accordance with the mixing ratio. In addition, while mining natural resources makes effective use of resources, it cannot be denied that it also has environmental destruction. In addition,
The techniques described in Japanese Patent Application Laid-Open No. 0-2044 and Japanese Patent Application Laid-Open No. 8-144487 also have the same problem as described above.

Therefore, in order to solve these problems,
It was conceived to develop humidity control by utilizing a chemical reaction or the like. For example, Japanese Patent Application Laid-Open No. Hei 7-284628 discloses a technique in which a cement-based hardened material is carbonated to exhibit humidity control. This is a technique in which when a cement-based hardened material is carbonated, a Ca component is selectively removed, so that silica gel having fine pores is left, and this exhibits a humidity control property. This technology has attracted attention as a concept of adsorbing carbon dioxide without problems such as environmental destruction, but on the other hand, once the cement compound is generated, crushing, particle size adjustment, molding, and carbonation must be performed. However, there remains a problem that the process becomes complicated.

In view of such circumstances, the present invention provides a method for producing a humidity control material which can not only eliminate the instability of the conventional material collection but also increase the material strength by relatively simple means. It is intended to be.

[0010]

The inventor has achieved the above object.
Of new substances that can be used as raw materials for humidity-control building materials
The blast furnace slag generated secondary to the steelworks
We focused on fine powder. Blast furnace slag fine powder, blast furnace cement
Has already been effectively used for raw materials and soil conditioners,
This is because it is a stable and proven material. But now
Until used as a substitute or supplement for cement
Most of the time, actively utilizing the inherent characteristics
I could not say that I was doing it. Therefore, the inventors
Is composed mainly of CaO and SiO2_Two, Al_TwoO_ThreeBut
Develops hydraulic properties due to inclusion and alkali stimulation
We focused on the properties of the blast furnace slag fine powder to be realized. Soshi
Production technology for hardened products based on blast furnace slag fine powder
On the way to develop _TwoAs a main component, and
Another raw material adjusted to a certain particle size range is
After blending in the appropriate amount at the end, cure and maintain under certain atmosphere
If it is found that it will be a useful humidity-control building material, the present invention will be completed.
It was done.

That is, according to the present invention, the blast furnace slag fine powder is 10 to 90 mass%, and the SiO ₂ content is
% Or more and the average particle diameter is 100 μm or less, 9 to 75 mass%, and the alkaline inorganic material is 1 to 2 mass%.
The mixed raw material mixed with 5 mass% is kneaded with water, and the temperature of the atmosphere is 0 to 260 ° C and the pressure is atmospheric pressure to 2.5M.
This is a method for producing a humidity-control building material, which is cured under the condition of Pa.

In this case, the content of SiO ₂ is 50 ma.
Mineral particles of ss% or more and having an average particle diameter of 100 μm or less are one or more kinds selected from clay, silica sand and silica fume, or the alkaline inorganic material is Ca (OH) ₂ , CaO, Mg (OH) ₂ , NaO
H, KOH, slaked lime, quicklime, Portland cement,
It is preferable that one or more kinds selected from blast furnace cement are used. In addition, the mixed raw material is further externally added with an aggregate of 0 to 70 mass% and / or a fibrous substance of 0 to 3%.
You may make it mix 0 mass%. However, in this case, 0 is not included.

In the present invention, mineral particles containing a SiO ₂ component whose particle size has been adjusted and a material exhibiting alkalinity (Ca-containing substance) are added to the blast furnace slag portion powder as a main raw material.
In addition to promoting the formation of the i-Ca hydrate phase, the resulting hydrate phase is converted into a CaO-SiO ₂
Beyond just -H ₂ O gel, zeolite-based compound,
Since tobamalite or the like is used, a good humidity control building material can be obtained. In addition, since the humidity control is a reflection of the phenomenon of adsorption of moisture to the fine pores existing in the structure, the phenomenon caused by the presence of the fine pores naturally appears. Therefore, the humidity control material obtained by the production method according to the present invention can be used for deodorization and adsorption of a chemical substance causing a sick house.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described along the history of the invention.

Generally, blast furnace slag is made of CaO, Si
O ₂ and Al ₂ O ₃ are the main components. When an alkali stimulant is added thereto or the cement is cured by adding cement, CaO-SiO appearing in the cement is obtained.
₂ -H ₂ O gels and _{CaO-Al 2 O 3 -H 2} O system phases are formed. However, such a system does not provide properties that can be used for a humidity control building material.

The inventor of the present invention has intensively studied whether there is a method capable of exhibiting humidity control even in such a system, and first thought that it may be effective to increase the content of SiO ₂ . The reason is, there conventionally, in materials such as ALC and calcium silicate plate holding the although humidity conditioning is not enough, to express the Tobamaraito phase _{(5CaO · 6SiO 2 · 5H 2} O), sufficient This is because it can be estimated that humidity control is obtained. However, these materials are composed of pure CaO and SiO ₂ such as lime and silica sand, and Al ₂
Generally, it does not contain O ₃ . Further, in order to form tobamalite, treatment using an autoclave was necessary. Here, the autoclave is a pressure vessel in which the pressure of the internal atmosphere is automatically increased due to a closed system when water is added to raise the temperature. Therefore, when the temperature of the container is increased with water therein, the vapor pressure (saturation pressure) is 1 atm at 100 ° C., but when the temperature is further increased, the vapor pressure further increases. Heating under such high pressure steam significantly increases the reaction rate of the substance.

Considering the above-mentioned existing humidity control materials and knowledge, it is considered that the reaction of simply mixing the raw materials does not exhibit not only the humidity control properties but also the sufficient strength as a cured product. Was done. Therefore, the inventor continued the research, and the important point for expressing the humidity control property is:
It was concluded that how quickly the SiO _{2 component} could contribute to the reaction. Then, the raw material having a high SiO ₂ content of
An experiment was conducted in which the mixture was ground to a particle size of 00 μm or less, mixed with a mixture of blast furnace slag fine powder and an alkali stimulant, and allowed to react in the presence of water, and a tobermorite phase (5CaO.6SiO _2.
Si-Ca hydrate phase to 5H ₂ O), including found that are formed stably. Further, although the exact structure is not _{known, CaO-SiO 2 -Al 2 O} 3 -H 2 O -based compounds also found that possible. The reaction of the conventional blast furnace slag with the alkali stimulant or cement alone was insufficient for the amount of SiO ₂ , and thus such compounds were difficult to form, but by supplying a separate SiO ₂ source, It is presumed that such a compound was formed by reacting with the Al ₂ O ₃ component of the blast furnace slag. The compound of this system is close to the natural mineral zeolite, and it is considered that this is effective for the expression of humidity control.

Therefore, the inventor has continued his research. In order to form these composite hydrate phases, the blast furnace slag fine powder, SiO ₂ should be contained at 50 mass% or more, and the average particle size should be 100 μm or less. A mixture of mineral particles and a material in which an alkali metal or an alkaline earth metal exhibiting an alkali when dissolved in water accounts for 50 mass% or more of the cation component, and forming the mixture into a predetermined shape in the presence of water;
The present inventors have found that curing may be performed at 0 to 260 ° C. at normal pressure or high pressure, and this is the present invention. Under conditions close to normal temperature and normal pressure, no tobermorite phase is formed, but Ca
Expression of _{O-SiO 2 -Al 2 O 3} -H 2 O -based compound, the humidity conditioning is considered to have been obtained. It was also found that when this compound was treated at an elevated temperature, the humidity control effect was further enhanced. Furthermore, when the treatment was carried out at a higher temperature and a higher pressure, a tobamalite phase was also formed, and the most effective humidity control performance was exhibited.

As specific heating means, in the present invention,
It is preferable to use an autoclave, in which case the high-pressure treatment is performed at a treatment temperature of 120 to 260 ° C and a treatment time of 1 to
It is better to carry out under the condition of 48 hours or less. More preferably, the processing temperature is 160 to 230 ° C, and the processing time is 1 to 24.
Less than hours is recommended. When the processing temperature is above the lower limit temperature (1
If the temperature is lower than 20 ° C.), the formation reaction of the tobermorite phase is delayed, and a sufficient amount of the tobermorite phase is not generated. If the treatment temperature exceeds the upper limit temperature (260 ° C.), the reaction is accelerated. The zonotorite phase (CaO.
This is because SiO ₂ · H ₂ O) is generated. It is said that the zonotolite phase has a humidity control effect, but sufficient casting strength cannot be obtained by simple casting or extrusion even if this phase is formed. In addition, the same behavior as the processing temperature appears for the processing time. That is, when the time is less than the above lower limit time (1 hour), the formation reaction of the tobermorite phase is delayed, so that a sufficient amount of the tobermorite phase is not generated, and the other Si-Ca hydrate phase is generated. On the other hand, if the treatment time exceeds the upper limit time (48 hours), the reaction is excessively promoted, and a zonotolite phase is generated, and in each case, sufficient strength of the cured product cannot be obtained.

Next, according to the study of the inventor, the amount of the raw material suitable for producing a hydrate phase appropriate for the above-mentioned hardening is determined by mixing (blending) the amount of the blast furnace slag fine powder. 10 to 90 mass% of the whole raw material, and a more preferable blending amount was 30 to 80 mass% of the whole. Further, it contains at least 50 mass% of SiO ₂ and has an average particle size of 100 μm.
The compounding amount of the following mineral particles was 10 to 75 mass%, more preferably 30 to 60 mass%. The compounding amount of the material exhibiting alkali when dissolved in water is 1 to 25 mass%, more preferably 5 to 2 mass%.
It was 0 mass%.

As blast furnace slag fine powder, JIS A
When the amount exceeds the upper limit (90 mass%), sufficient humidity control cannot be obtained, and when the amount is less than the lower limit, sufficient cured body strength can be obtained. Absent. Mineral particles containing 50 mass% or more of SiO ₂ and having an average particle size of 100 μm or less are:
If the amount exceeds the upper limit (75 mass%), sufficient cured body strength cannot be obtained, and if the amount is less than the lower limit (9 mass%), humidity control cannot be obtained. 50% of this SiO ₂
As the mineral particles containing s% or more and having an average particle diameter of 100 μm or less, fly ash, white clay, volcanic ash, and silica fume generated from a thermal power plant can be used. Can be used. Of these, fly ash and clay are more desirable. Since SiO ₂ is the main component and most of the by-products are formed of CaO and Al ₂ O ₃ , the resulting composite hydrate is not damaged, and the composition is relatively stable. This is because the quality of the obtained cured product can be stabilized. Further, if the material exhibiting alkali exceeds the upper limit (25 mass%) of the above-mentioned composition, general CaO—S
When the reaction of the iO ₂ system and the reaction of CaO—Al ₂ O ₃ exceed the formation reaction of the tobermorite phase, the development of the humidity control property due to the development of the composite hydration phase cannot be expected. If the reaction falls below the lower limit (1 mass%), sufficient Hardened body strength cannot be obtained. As the material exhibiting the alkali, any material may be used as long as the alkali metal or the alkaline earth metal accounts for 50% or more of the cation component, and Ca (OH) ₂ , CaO, Mg (O
H) ₂ , NaOH, KOH, Portland cement,
Slaked lime, quicklime, blast furnace cement and the like can be used.

In the present invention, depending on the use of the cured product to be produced, it has been considered that the bending strength of the cured product is enhanced by adding a material or fiber corresponding to the aggregate to the above-mentioned basic mixed raw material. . For example, in order to use the cured product as a substitute material for humidity-controllable concrete such as clay concrete, it is necessary to provide an aggregate because a large construction area is required in volume stability. The amount of aggregate used is optional, but if it exceeds 70 mass%,
Since the proportion of the mixed raw material in the total volume is low and the surface cannot be covered, this value is set as the upper limit. As the aggregate, those commonly used may be used, but more preferably, converter slag, smelting reduction furnace slag, electric furnace slag, blast furnace slow cooling slag, and stainless steel refining slag are used. In the compounding of the raw material according to the present invention, the specific gravity of the powder portion is lighter than that of a normal concrete raw material, and therefore, the cured product is slightly lighter than concrete. If converter slag, smelting reduction furnace slag, electric furnace slag, blast furnace slow cooling slag, and stainless steel smelting slag are used, their specific gravity is heavier than ordinary aggregate, so the hardened body is integrated with ordinary concrete. Equal weight (related to workability)
It is because it can secure. Further, in the present invention, if the Ca compound is used as an aggregate, it is more preferable since the adhesion around the Ca compound is improved and the reaction of the paste portion is accelerated.

On the other hand, in order to apply the cured product to a wall material or a ceiling material, it is necessary to form the cured product into a thin board. In that case, it is necessary to ensure a sufficient bending strength, so it is desirable to add a fibrous substance to the mixed raw material. The amount of the fibrous substance is preferably suppressed to 25 mass% or less in order to ensure board handling and molding performance. Molding is possible even if it exceeds this, 70mas
The reason for this is that the humidity control property does not significantly decrease up to s%, but the kneading with the mixed raw material is difficult, and time and energy are required for homogenization, resulting in disadvantages in actual work. The type of the fibrous substance is not particularly limited in the present invention, and general artificial fibers such as glass wool and rock wool,. Any of natural inorganic fibers such as wollastonite and sepiolite and organic fibers such as cellulose, pulp and vinylon can be used.

The cured product produced by the method according to the present invention as described above has an appropriate strength and also has a humidity control effect, so that it can be effectively used as a humidity control building material. Also,
It can also be used for deodorization and adsorption of chemical substances that cause sick houses. In particular, since the mixed raw material is kneaded with water and poured into a mold, it can be easily formed into various shapes, so it is formed and used as a building material for various uses such as various tiles, panels, boards, bricks and blocks. it can. Also, if cast molding is performed at the construction site, it can be suitably used for applications such as clay concrete.

[0025]

EXAMPLES (Example 1) Various raw materials having the component compositions shown in Table 1 were weighed by predetermined amounts, water was added and mixed, and the mixture was poured into a stainless steel container (mold) and molded. Curing was performed at various treatment temperatures and times. The amount of water added to the mixed raw material was fixed at water amount / raw material amount = 0.45. Curing time is 6 hours at each temperature.
Those kept at 20 ° C. for 28 days were evaluated.

[0026]

[Table 1]

The cured product obtained by these curing treatments was measured for flexural strength by a method in accordance with JIS R 2553, and the moisture control performance of the cured product was 20 ° C., 50 RH.
(Relative humidity is abbreviated) The humidity in the tank maintained at% was raised to 90 RH%, the weight change at that time was measured, the amount of moisture absorption per surface area was calculated, and the tank was kept at 90 RH% for 24 hours. The humidity in the sample was returned to 50 RH%, and the weight change was measured and evaluated in the same manner. In addition, the same measurement was performed about the commercially available humidity control tile as a comparison. The results are shown in Table 1 collectively, and FIG. 1 shows the change over time in the moisture absorption of a part of the cured product.

From Table 1, according to the production method of the present invention,
A cured product obtained by heating and curing the mixed raw material under high-pressure steam, particularly, when the mixed raw material is processed with the mixing ratio of the mixed raw material, the curing time, and the processing temperature of the autoclave being in appropriate ranges, has a good hardened state (flexural strength of 9 MPa or more) and good control. It is evident that it has wet performance (equivalent to or better than commercial humidity conditioned tiles). In addition, in formulations 7 to 9 containing fibers, there are no fibers,
The flexural strength is even higher than that of the similar composition, and it is judged that fiberization is effective when thinning building materials.

(Example 2) Based on Formulation 14 of Formulation 1 shown in Example 1, a predetermined amount of aggregate was added, and the mixture was cast and cured at 20 ° C for 28 days. Since the aggregated material is used in the same manner as the concrete or the interlocking block, the strength of the cured product was evaluated by the compressive strength. Table 2 shows the measurement results of the composition, compressive strength, and humidity control performance. Even if the aggregate was added, there was no problem in the strength of the cured product, and although the humidity control performance slightly decreased as the amount of the aggregate increased, sufficient characteristics were obtained.

[0030]

[Table 2]

[0031]

As described above, according to the present invention, not only the instability of the conventional raw material collection can be eliminated but also the use of blast furnace slag as a main raw material, and a high-strength humidity control material can be manufactured. . As a result, blast furnace slag, which was conventionally used as an auxiliary material, fly ash and various slags with relatively low added value, can now be used as building materials and civil engineering materials with humidity control performance. The invention greatly contributes to the reuse of resources and the improvement of the environment.

[Brief description of the drawings]

FIG. 1 is a diagram showing the change over time in the amount of moisture absorption of a humidity-controlled building material obtained by a production method according to the present invention.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) E04B 1/64 E04B 1/64 D E04C 2/04 E04C 2/04 F // (C04B 28/08 C04B 28 / 08 14:06 14:06 Z 14:10 14:10 Z 18:14 18:14 Z 7:02 7:02 7:14) 7:14 111: 00 111: 00 (72) Inventor Masato Takagi Chiba 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Japan F-term in the Technical Research Laboratory, Kawasaki Steel Corporation (reference) 2E001 DB03 FA03 FA10 FA11 FA14 GA11 HA01 JA06 2E162 CA01 FA00 4G012 MA00 MA02 PA00 PA03 PA04 PA05 PA28 PB03 PC11 PE07

Claims (4)

[Claims] 1. A blast furnace slag fine powder of 10 to 90 mass
%, SiO ₂ content is 50 mass% or more, and the average particle diameter is 100 μm or less.
s%, a mixed raw material containing 1 to 25 mass% of an alkaline inorganic material is kneaded with water, and the temperature of the atmosphere is 0 to 2%.
A method for producing a humidity-controlled building material, comprising curing at 60 ° C. and a pressure of atmospheric pressure to 2.5 MPa. 2. The method according to claim 1, wherein the mineral particles having an SiO ₂ content of 50 mass% or more and an average particle diameter of 100 μm or less are one or more selected from clay, silica sand, and silica fume. The method for producing a humidity control building material according to claim 1. 3. The method according to claim 2, wherein the alkaline inorganic material is Ca (O
H) ₂ , CaO, Mg (OH) ₂ , NaOH, KOH, slaked lime, quicklime, Portland cement, blast furnace cement, or one or more kinds thereof. Manufacturing method of wet building materials. 4. The mixed raw material further contains 0 to 70 mass% of an aggregate and / or 0 to 30 m of a fibrous substance.
The manufacturing method of the humidity control building material according to any one of claims 1 to 3, wherein the assembling is performed by ass%.