JP2000344564A - Lightweight hydraulic composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a safe and low cost hardened body excellent in handling at the time of forming and having sufficient practical strength by blending the incineration ash of paper sludge as a lightweight aggregate in a composition containing granulated blast furnace slag, a water soluble high polymer and a hardening stimulator. SOLUTION: The incineration ash obtained by firing paper sludge is added by about 1-200 pts. as the lightweight aggregate into 100 pts. composition containing the granulated blast furnace sludge, the water-soluble high polymer and the hardening stimulator. The incineration ash is composed of a porous crystalline body of a fired body of clay minerals, which are additives for paper, and desirably has about <=1.8 kg/l bulk density, about <=5 mm particle diameter and pH >=8 of washing liquid. The granulated blast furnace slag desirably has >=2000 cm2/g Blaine value and if necessary, about 50 pts. fume is added to 100 pts. slag. As the water soluble high polymer, about 0.1-10 pts. sodium polyacrylate is desirably used and as the hardening stimulator, about 0.1-6 pts. sodium hydroxide is desirably used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight hydraulic composition which can be used for wall materials, floor materials, roof materials and interior materials.

[0002]

2. Description of the Related Art Conventionally, building materials obtained by curing a hydraulic composition have been reduced in weight for the purpose of handling during construction and reducing the weight load applied to the building. There are various methods for reducing the weight, such as foaming the material itself or having a hollow shape. One of these methods is to reduce the specific gravity by adding a lightweight aggregate. Have been done. The lightweight aggregate used at this time generally includes inorganic substances such as pearlite, diatomaceous earth, pumice stone, sepiolite, shirasu balloon, vermiculite, and organic compounds such as expanded styrene beads and expanded polypropylene beads.

[0003] However, these lightweight aggregates are crushed, washed, separated, dried, fired, etc., of quarried inorganic materials, and thus have a problem in cost. In addition, although the organic compound has a high lightening effect, it is not preferable from the viewpoint of the nonflammability of the material, and has a problem in cost.

[0004] For the purpose of reducing the cost of these aggregates, fly ash, which is industrial waste, and incinerated ash of general waste are also added. These have the advantage of being inexpensive due to industrial waste. In addition, it is preferable to effectively use such industrial waste from the viewpoint of recycling.

[0005] However, fly ash generally has a high specific gravity and has no light weight effect. Some of them are separated from those having a low specific gravity, but there is a problem that the cost is high due to separation and drying. Further, since various types of incineration ash of general garbage are incinerated, it is difficult to produce a stable product because the quality is not constant. Furthermore, it may contain harmful substances such as heavy metals and dioxins, which is not preferable for safety. In addition, these incinerated ashes having a strong alkalinity have a hardening promoting effect when added to cement, and have a problem in handling at the time of molding.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is a light-weight hydraulic composition that is safe, inexpensive, has excellent handling during molding, and has a sufficient practical strength. The purpose is to provide the body.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, completed the present invention. That is, the present invention

(1) A lightweight hydraulic composition characterized by mixing paper sludge incineration ash as a lightweight aggregate with a composition comprising granulated blast furnace slag, a water-soluble polymer, and a hardening stimulant; (2) pH of cleaning solution when incinerated ash is washed with water
(8) water is added to the composition described in (1) or (2), wherein water is added to the composition described in (1) or (2) above, and after molding, if necessary, curing. It relates to a cured product obtained by curing.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The granulated blast furnace slag used in the present invention preferably has a Blaine specific surface area of not less than 2,000 cm ² / g, particularly preferably not less than 3,000 cm ² / g.

[0010] The lightweight hydraulic composition of the present invention improves the moldability at the time of extrusion molding, the fluidity at the time of cast molding, and the mechanical strength of the backing material after curing and curing, and the composite material. It is particularly preferable to use silica fume because of its remarkable effects. The amount of silica fume used depends on the particle size and type of granulated blast furnace slag and the type and amount of other various admixtures added as necessary, but is usually 100 parts by weight of granulated blast furnace slag. The amount is preferably 2 to 50 parts by weight, particularly preferably 5 to 25 parts by weight.

Specific examples of the water-soluble polymer that can be used in the lightweight hydraulic composition of the present invention include poly (meth) acrylates such as sodium poly (meth) acrylate, potassium poly (meth) acrylate, and lithium poly (meth) acrylate. There are meth) acrylate, carboxymethyl cellulose and the like, and preferred is sodium polyacrylate.

These water-soluble polymers are preferably selected from those having an appropriate molecular weight depending on the composition and the molding method, and are not particularly limited. For example, sodium polyacrylate is extruded. If the molecular weight is 100,
Those having a high molecular weight of 000 or more are preferably used, and those having a molecular weight of 500,000 or more are particularly preferably used. When casting is performed, those having a molecular weight of 500,000 or less and 1,000 or more are preferably used.

It is preferable that these water-soluble polymers are promptly dispersed in the composition when the composition is kneaded,
In practice, it is preferable to use an aqueous solution of these water-soluble polymers or a finely pulverized powder or bead.

The amount of the water-soluble polymer used varies depending on the required properties of the material, the molding method, and the like.
The amount is usually 0.1 to 10 parts by weight, preferably 0.3 to 7 parts by weight, particularly preferably 0.5 to 5 parts by weight with respect to 00 parts by weight. If the amount of the water-soluble polymer used is too small, kneading becomes difficult or the moldability decreases, depending on the amount of water to be added. Further, if the amount of the water-soluble polymer used is too large, curing becomes difficult, and even if cured, water resistance deteriorates.

Various alkaline substances can be used as the curing stimulant. For example, alkali metal hydroxides such as sodium hydroxide, potassium hydroxide and lithium hydroxide; alkali metal carbonates such as sodium carbonate, potassium carbonate and lithium carbonate; alkalis such as sodium bicarbonate, potassium bicarbonate and lithium bicarbonate. Metal bicarbonate, further calcium hydroxide, potassium pyrophosphate, dipotassium phosphate, tripotassium phosphate, trisodium phosphate, sodium (meth) silicate,
And potassium (meth) silicate. Of these curing stimulants, alkali metal hydroxides are preferred, and sodium hydroxide is particularly preferred. These curing stimulants can be used either as a solid or as an aqueous solution, but are preferably used as an aqueous solution because they are easily dispersed uniformly in the composition during kneading of the composition.

The amount of the curing stimulant used depends on its basicity, the particle size of the granulated blast furnace slag, the type and amount of the admixture (described later) added as necessary, and the amount of water.
It is generally 0.1 to 6 parts by weight, preferably 0.2 to 4 parts by weight, based on 100 parts by weight of the total amount of granulated blast furnace slag and various admixtures.

If the amount of the curing stimulant is too small, the molded cured product cured by wet curing may not exhibit sufficient strength,
It is industrially disadvantageous, for example, it takes a long time for curing and curing. On the other hand, if the amount is too large, the curing speed becomes too high, and handling in the kneading process and the molding process may be significantly impaired.

The incineration ash used in the present invention is not particularly limited as long as paper sludge generated in the pulp manufacturing process is incinerated. Generally, the components of these incinerated ash are viscous minerals such as talc, kaolin and activated clay added to paper. These clay minerals become porous crystals at the stage of firing. Generally, incinerated ash fired at 600 ° C. or higher, preferably 800 ° C. or higher is used.

The bulk specific gravity and particle size of these incinerated ash vary depending on the type and blending ratio of the clay mineral, firing conditions, etc., but the bulk specific gravity is 1.8 k.
g / l or less, a particle size of 5 mm or less, more preferably a bulk specific gravity of 1.0 kg / l or less, and a particle size of 2 mm or less are preferable. In addition, it is preferable to use incineration ash in which the pH of the water washing liquid of the incineration ash is 8 or more. The amount of incinerated ash is 100 in total of granulated blast furnace slag and other various admixtures described later.
It is usually 1 to 200 parts by weight, preferably 3 to 60 parts by weight based on parts by weight.

In order to further reduce the weight, these incinerated ash may be used in combination with other lightweight aggregates. Specific examples of the lightweight aggregate that can be used include fly ash balloon, perlite, zeolite, diatomaceous earth, pumice stone, shirasu balloon and the like. The compounding amount of these lightweight aggregates is usually 1 to 100 parts by weight, preferably 5 to 50 parts by weight based on 100 parts by weight of the total amount of granulated blast furnace slag and other various admixtures. .

In the lightweight hydraulic composition of the present invention, various admixtures can be further used, if necessary.
Examples of the admixture include pulverized slow-cooled slag, ferrochrome slag, wollastonite, silica, alumina, talc, silica sand, silica stone powder, clay, kaolin, calcium carbonate, pulverized ceramics, titania, zirconia, and gravel. Examples include inorganic fillers, carbon fibers, glass fibers, pulp, fiber materials such as nylon, vinylon, polyester, acrylic, and polypropylene, surface treatment agents such as silane coupling agents, and pigments.

The amounts of these various admixtures vary depending on the type of the admixture and the purpose of use. For example,
In the case of the inorganic filler, it is usually used in an amount of 10 to 300 parts by weight based on 100 parts by weight of the granulated blast furnace slag. The amount of the fibrous material is usually 0.2 to 30 parts by weight. In the case of an admixture such as a surface treatment agent or a pigment, the granulated blast furnace slag 10
It is usually used in an amount of 0.1 to 20 parts by weight based on 0 part by weight.

The lightweight hydraulic composition of the present invention can be obtained by uniformly mixing the above components at a predetermined ratio. The light-weight hydraulic composition thus obtained can be cured after adding water, mixing, molding if necessary. The molding method is not particularly limited as long as a product having a predetermined shape can be obtained, and usually includes casting, extrusion, and press molding. Also, after curing,
Processing such as grinding and cutting may be performed.

The amount of water used depends on the type and amount of granulated blast furnace slag to be used, the type and amount of water-soluble polymer, the type and amount of hardening stimulant, and other various admixtures added as necessary. Depending on the type and amount, it is important to determine the mixture so that it has good kneading properties.However, when manufacturing by extrusion or press molding, the total amount of granulated blast furnace slag and other various admixtures 8 to 80 parts by weight, preferably 10 to 60 parts by weight, more preferably 12 parts by weight per 100 parts by weight
５５55 parts by weight. When the material is produced by the casting method, the granulated blast furnace slag and the other various admixtures are 12 to 100 parts by weight, preferably 14 to 80 parts by weight, more preferably 14 to 80 parts by weight, based on 100 parts by weight in total. 16-60
Parts by weight.

Curing and curing are preferably carried out by wet curing. Usually, the curing is carried out at a temperature of 40 to 100 ° C. under a saturated vapor pressure.
It is performed in the range of 100 hours.
The autoclave treatment may be performed at a temperature of not less than ° C. In addition, under the condition of coating well with a film etc. and not drying,
Curing may be performed at a temperature of 40 to 100 ° C.

Drying the molded article after curing and curing is performed by:
It is preferable from the viewpoint of strength development and dimensional stability. The drying ratio at this time depends on the ratio of the composition, the molding method, etc.,
5% to 90% of usually used water, preferably 30% to 8%
Dry 0%. Further, the drying temperature is from 10 to 200C, preferably from 50C to 160C.

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 A blender equipped with a stirrer was used.
90 parts by weight of granulated blast furnace slag of m ² / g, 10 parts by weight of silica fume, 2 parts by weight of sodium polyacrylate (trade name: Panakayak B (manufactured by Nippon Kayaku Co., Ltd.)), 9 parts by weight of corrugated cardboard pulp, Paper sludge incineration ash (bulk specific gravity: 0.1
7 kg / 1, pH of water washing liquid 11.3, particle size 400 μm
20 parts by weight) were stirred and mixed for 90 seconds. Subsequently, 45 parts by weight of a 6.7% sodium hydroxide solution was added as a curing stimulant, followed by stirring and mixing for 30 seconds to obtain a mixture (light-weight hydraulic composition of the present invention). Next, the composition obtained by the stirring and mixing was put into a roll kneader-type kneader and kneaded for 5 minutes to obtain a clay-like kneaded material. Furthermore,
This kneaded product was extruded by a vacuum extruder under a reduced pressure of 20 mmHg to obtain a molded product having a thickness of 10 mm and a width of 100 mm. The obtained molded body is subjected to temporary curing at 60 ° C. for 4 hours,
Further, the composition was subjected to wet curing and curing under an atmosphere of a saturated steam pressure of 90 ° C. for 12 hours to obtain a cured product (A-1) of the present invention.

Example 2 A blender equipped with a stirrer was used to add a Brain specific surface area of 4000 c.
90 parts by weight of granulated blast furnace slag of m ² / g, 10 parts by weight of silica fume, 2 parts by weight of sodium polyacrylate (trade name: Panakayak B (manufactured by Nippon Kayaku Co., Ltd.)), 9 parts by weight of corrugated cardboard pulp, Paper sludge incineration ash (bulk specific gravity: 0.1
5 kg / l, pH of water washing liquid 11.3, particle size 2 mm to 8
(00 μm) was stirred and mixed for 90 seconds in 20 parts by weight. Subsequently, 49 parts by weight of a 6.7% sodium hydroxide solution was added as a hardening stimulant, and the mixture was further stirred and mixed for 30 seconds to obtain a mixture (light-weight hydraulic composition of the present invention). Next, the composition obtained by the stirring and mixing was put into a roll kneader-type kneader and kneaded for 5 minutes to obtain a clay-like kneaded material. Further, the kneaded product was extruded by a vacuum extruder under a reduced pressure of 20 mmHg to obtain a molded product having a thickness of 10 mm and a width of 100 mm. The obtained molded body is subjected to temporary curing at 60 ° C. for 4 hours, and further under an atmosphere of a saturated steam pressure of 90 ° C. for 12 hours.
The cured product (A-2) of the present invention was obtained by wet curing.

COMPARATIVE EXAMPLE 1 A blender equipped with a stirrer was used.
90 parts by weight of granulated blast furnace slag of m ² / g, 10 parts by weight of silica fume, 2 parts by weight of sodium polyacrylate (trade name: Panakayak B (manufactured by Nippon Kayaku Co., Ltd.)), and 6 parts by weight of corrugated cardboard pulp Stir and mix for 90 seconds. Subsequently, a 6.7% sodium hydroxide solution 27 is used as a curing stimulant.
Parts by weight were added, and the mixture was further stirred and mixed for 30 seconds. Next, the composition obtained by the stirring and mixing was put into a roll kneader-type kneader and kneaded for 5 minutes to obtain a clay-like kneaded material.
Further, this kneaded product was extruded by a vacuum extruder under a reduced pressure of 20 mmHg to obtain a comparative molded body having a thickness of 10 mm and a width of 100 mm. The obtained molded body was subjected to provisional curing at 60 ° C. for 4 hours, and further subjected to wet curing and curing for 12 hours in an atmosphere of a saturated steam pressure of 90 ° C., and a molded cured body of the hydraulic composition of Comparative Example (B-1) ) Got.

Test Example The curing start time, specific gravity, and bending strength of the molded articles of Examples 1 and 2 and Comparative Example 1 were measured. The curing start time was measured by placing the molded product in a plastic bag and placing it in a thermostat at 40 ° C., and then measuring the hardness with a fruit hardness meter every 5 minutes. The fruit hardness became 3.0 kg / cm ² or more. The time taken was taken as the curing start time. Table 1 shows the measurement results.

Table 1 Specific gravity (kg / l) Curing start time (min) Flexural strength (kgf / cm ² ) Example 1 1.90 162 175 Example 2 1.82 161 145 Comparative example 1 2.20 160 135

As described above, the cured product of the lightweight hydraulic composition of the present invention has a low specific gravity and has a sufficient practical strength. Also, even if the added incineration ash has a high alkalinity, it does not affect the curing start time.

[0034]

The lightweight hydraulic composition of the present invention uses incinerated ash obtained by firing paper sludge, which is industrial waste, as a lightweight aggregate, so that the cost is low. In addition, since these incinerated ash do not contain halogen compounds such as chlorine and heavy metals in the raw materials, they are safe without harmful substances such as dioxins and heavy metals. In addition, since cement is not included as a hydraulic substance, even if the incineration ash has a high alkalinity, the curing speed hardly changes, so that handling during molding is not affected.

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) C04B 111: 20

Claims (3)

[Claims] 1. A lightweight hydraulic composition comprising a composition comprising granulated blast furnace slag, a water-soluble polymer, and a hardening stimulant, and incinerated ash obtained by firing paper sludge as a lightweight aggregate. . 2. The pH of the washing liquid when the incinerated ash is washed with water is 8;
The lightweight hydraulic composition according to claim 1, wherein the incinerated ash is used. 3. A cured product obtained by adding water to the composition according to claim 1 or 2, mixing, forming as required, and curing and curing.