KR100809804B1 - Light foam concrete composition using bottom ash, used for sound absorbtion materials, light foam concrete product employing the same and the manufacturing method thereof - Google Patents

Abstract

A lightweight foam concrete composition for sound-absorbing materials is provided to have heat resistance and water resistance, retain original performances and shape even after firing, and be harmless to environment. A lightweight foam concrete composition for sound-absorbing materials includes: a powder comprising 40-50 parts by weight of bottom ash powder, 40-50 parts by weight of ordinary portland cement and 2-10 parts by weight of alumina cement, 2-10 parts by weight of anhydrite, and 1-5 parts by weight of slaked lime based on 100 parts by weight of the total powder; 70-90 parts by weight of water based on 100 parts by weight of the powder except for the bottom ash; and 200-300 % by volume of foam based on 100 % by volume of the powder slurry comprising the powder and water. The foam is obtained by diluting 2-4wt%, based on water, of an alkylethersulfate ester salt as a foaming agent with water, and pre-foaming the mixture. Further, a size of the foam is 0.3-1.4mm and an average size of the foam is 1.2mm.

Description

Light foamed concrete composition for sound absorbing material using bottom ash, light foamed concrete product for sound absorbing material using same and method for manufacturing thereof light emitting concrete composition using bottom ash, used for sound absorbtion materials, light foam concrete product employing the same and the manufacturing method }

1 is a flow chart for the manufacturing step of the lightweight foam concrete according to an embodiment of the present invention,

2 is a graph for the temperature and time of the steam curing step in the production of lightweight foam concrete according to an embodiment of the present invention,

Figure 3 is a graph of the pressure, temperature and time of the autoclave curing step in the production of lightweight foam concrete according to an embodiment of the present invention.

The present invention relates to a concrete composition for lightweight foamed concrete products used as sound absorbing materials in the construction industry, and to a method for manufacturing the concrete product. It is about a product.

Generally, sound absorbing materials are classified into porous sound absorbing materials, hollow sound absorbing materials, and plate-shaped sound absorbing materials, but most of them are porous sound absorbing materials such as rock wool, glass wool, and polyurethane. Porous sound absorbing materials are harmful to the human body and are limited in use. In addition, polyurethane is harmless to the human body, but the price is expensive and the sound absorption is inferior to the glass surface. Conventional fibrous sound-absorbing material is weak in fire resistance, has been a problem to use due to the durability and harmfulness to the human body according to the material properties.

In addition, foamed concrete, foamed porous concrete prepared by adding chemicals to cement, may be used. Such foamed concrete is used because it is lightweight and has excellent sound absorption effect.

Conventional foaming agents used in the manufacture of foam concrete include animal, vegetable, protein foaming agents or aluminum powder, anionic surfactants, etc., but animal protein foaming agents have advantages in manufacturing that the foam is stable and does not generate much settling cracks due to its own weight. However, the amount of foaming is very small compared to other types of foaming agents, and there is a disadvantage that the size of the foam becomes smaller after curing. In addition, the use and storage of the smell of animal-specific odor, so handling and storage is difficult and very difficult to use.

Vegetation protein foaming agent bubbles appear when the bubbles are generated faster than other foaming agents, and after curing the solids appear to sink phenomenon is very difficult to maintain the phenomenon.

Aluminum powder is generally used for the production of lightweight foam concrete (ALC), but has the disadvantage of high price and difficulty in forming continuous bubbles.

The present inventors have completed the present invention as a result of research to manufacture a lightweight foam concrete product exhibiting more excellent sound absorption characteristics while solving the existing problems.

It is an object of the present invention to provide a lightweight concrete composition for sound absorbing material having high heat resistance, water resistance, maintaining its original performance and shape even after a fire, and having no danger to the environment, a concrete product using the same, and a method of manufacturing the same.

In order to achieve the object of the present invention,

Powder containing 40 to 50 parts by weight of bottom ash fine powder, 40 to 50 parts by weight of Portland cement and 2 to 10 parts by weight of alumina cement, 1 to 5 parts by weight of anhydrous gypsum and 1 to 5 parts by weight of calcined lime, based on the total weight of powder 100;

70 to 90 parts by weight of water based on the weight of the powder except for the bottom ash 100; And

It contains a bubble in a volume of 200 ~ 300 volume ratio with respect to the volume 100 of the powder slurry consisting of the powder and water,

Wherein the bubble is characterized in that the light-weight foam concrete composition for sound absorbing material, characterized in that the surfactant is diluted to 2 to 4% by weight with water to be prepared and mixed in a pre-foaming method.

As said surfactant, an anionic surfactant and alkyl ether sulfate ester salt are preferable.

In the concrete composition, the bottom ash, which is a siliceous material, and the cement, which is a calcium material, may generate tobermorite hydrate at 180 ° C. or more by an autoclave after mixing.

According to one embodiment of the present invention, the bubble is 0.3 ~ 1.4mm in size, the average bubble size is about 1.2mm, it is preferable to maintain the porosity 50 ~ 80%, the soft porosity 10 ~ 40%.

For another object of the present invention

Preparing a powder mixture by dry-beaming cement, alumina cement, hydrated lime and anhydrous gypsum in a bottom ash powder for 1 to 2 minutes;

Preparing a powder slurry by mixing a mixed solution of water and a water reducing agent previously mixed with the powder mixture mixed by the dry beam;

Preparing a powder bubble slurry by mixing bubbles in the powder slurry;

Pre-curing step of injecting the powder bubble slurry into a mold for 3 to 4 hours air curing at room temperature, and steam curing for 4-6 hours at 60 ~ 80 ℃ after the air curing step; And

After the pre-cure step 150 to 180 ℃, including the step of steam curing for 8 to 10 hours at a high temperature and high pressure of 8 to 10 atm,

Bubbles mixed in the powder bubble slurry step is characterized in that the manufacturing method of the lightweight foam concrete, characterized in that produced by the pre-foaming method by adding the surfactant to 2 to 4% by weight with respect to water.

Hereinafter, the present invention will be described in more detail.

Lightweight concrete composition for sound absorbing material according to the invention is 40 to 50 parts by weight of bottom ash fine powder, 40 to 50 parts by weight of ordinary Portland cement and 2 to 10 parts by weight of alumina cement, 2 to 10 parts by weight of anhydrous gypsum, Powder containing 1 to 5 parts by weight of lime; 70 to 90 parts by weight of water based on the weight of the powder except for the bottom ash 100; And a bubble at a volume ratio of 200 to 300 with respect to a volume of the powder slurry consisting of the powder and water, wherein the bubbles are prepared by diluting the surfactant-based foaming agent with water to 2 to 4% by weight in a pre-foaming manner. It is characterized by a light weight foam concrete composition for sound absorbing material. The content of the foaming agent affects the properties of the bubbles generated in the bubble group (30 liter of foaming agent solution) which generates foam. This is because the sound absorbing material absorbs the negative wavelength only when the continuity (which must be followed) of the fine bubbles is high, unlike the sound insulating material. That is, in order to secure the continuity of the bubbles, bubbles must be deflected to some extent during curing of the concrete composition. The sound absorbing material reflects sound, but the sound absorbing material absorbs sound, and the longer the bubble in the sound absorbing surface, the longer the absorbed sound can be dissipated as heat energy. Therefore, in the case of producing a bubble by adding a foaming agent in the above range, the properties of the resulting bubble is advantageous for the production of sound absorbing material is preferable.

As said surfactant, an alkyl ether sulfate ester salt is preferable.

In addition, even if bubbles are formed by mixing the same foaming agent, that is, 30 liters of the foaming agent aqueous solution, the continuity of the bubbles may vary greatly depending on how much water is added later. It can not exhibit the characteristics of the sound absorbing material. Therefore, when the content of the amount of water input to the slurry having the bubble is pre-foamed bubbles are defoamed at an appropriate level.

The bottom ash is a residue that remains after incineration or combustion, and is attached to a furnace wall, a superheater, a reheater, etc. of a power plant incinerator such as a thermal power plant, and refers to a combustion product that is collected on the bottom of the boiler by its own weight. If the particle size is 100 μm or less, it is treated as a fly ash (flying combustion product). That is, when the coal powder is burned, the organic material is burned as fuel and the inorganic material remains as "ash", while the ash is dispersed in the boiler communication, the heavy particles fall to the bottom of the boiler, and the particles are heavy and the bottom The ash falling out is called the “bottom ash”, and the fly ash collected in the dust collector during the coal ash is about 60-80%, and the remaining 20-40% is bottom ash collected from the bottom of the boiler. The main component of the bottom ash is an inorganic material, for example, SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ .

Bottom ash has a particle size ranging from 1 to 2.5 mm, and a recycling rate of about 15% is very low. The ash ash is limited to roadbeds for road use, and is mostly reclaimed without being recycled. However, according to the present invention, since the bottom ash can be used to manufacture lightweight foamed concrete with excellent sound insulation performance, it is an excellent invention having a great effect in preventing environmental pollution as well as recycling of resources.

One component cement in the concrete composition according to the present invention is portland cement. The main components are lime CaO, silica SiO ₂ , alumina Al ₂ O _3, and iron oxide Fe ₂ O ₃ . Here, the CaO component, which is the main component of the portland cement, is hydrothermally synthesized with the SiO ₂ component of the bottom ash by autoclave at 180 ° C. or more to prepare a lightweight calcium silicate cured body which is a tobermorite hydrate, which is a stable lightweight / porous crystal.

Therefore, according to the present invention, the coal ash (fly ash, bottom ash) generated in the thermal power plant contains many SiO ₂ components necessary for CaO / SiO ₂ hydrothermal synthesis reaction, and also contains some CaO, which is a stable lightweight / porous crystal. A lightweight calcium silicate cured product, which is a light hydrate, may be manufactured, and the porous cured body may be smoothly formed by controlling the curing reaction rate of the initial slurry by the Al ₂ O ₃ and Fe ₂ O ₃ components included in the bottom ash.

Thus the concrete composition of the present invention is stable and lightweight / porous determine the soil beomo result to smoothly form a light baggage, the essential CaO and SiO ₂ to CaO / SiO ₂ hydrothermal synthesis reaction blending the components of the concrete composition of CaO / SiO ₂ The molar ratio of is preferably 0.8 to 1.2, preferably 1.1.

Light-weight foam concrete product for sound absorbing material according to the present invention is made of a composition according to the present invention, the manufacturing method in one step, 40 to 50 parts by weight of bottom ash fine powder, usually 40 to 50 parts by weight of Portland cement, based on the total powder weight 100 2 to 10 parts by weight of parts and alumina cement, 2 to 10 parts by weight of anhydrous gypsum and 1 to 5 parts by weight of calcined lime are mixed and the materials are mixed in a dry powder.

In the second step, mixing the dry powder mixture and the blended water obtained by diluting the anionic surfactant to 2 to 4% in water are carried out in a mixer for 2 to 3 minutes. At this time, the flow state of the prepared powder slurry is to pour the slurry into the flow cone of diameter Φ50mm, height 50mm, and then lift the flow cone to measure the state that no more spreading, so that the diameter of 200mm comes out desirable.

Step 3 uses bubbles foamed through the bubble generator. The bubbles thus prepared have a size of 0.3 to 1.4 mm and an average bubble size of about 1.2 mm, and preferably maintain a porosity of 50 to 80% and a soft porosity of 10 to 40%. This is because the optimum sound absorption rate can be shown. The step 3 is preferably performed so that the slurry and the bubble is uniformly mixed while the bubbles are not deflected in the process of mixing the bubbles.

Step 4 is a step of injecting the powder bubble slurry prepared in step 3 into the mold so that there is no difference in specific gravity in the mold.

Step 5 is air cured at room temperature for 3 hours or more so that the powder bubble slurry injected into the mold has a strength of 3-4 kg / cm ² or more, and steam curing at 60-80 ° C. for 2-4 hours after the air curing step. Steam curing according to an embodiment of the present invention, see FIG.

Step 6 is a high temperature and high pressure steam curing for 6 to 10 hours at a high temperature and high pressure of 150 ~ 180 ℃, 7-12 atm after the step 5. After drying to 10 + 3% moisture content, lightweight foam concrete products for absorbers are completed.

The present invention will be described in more detail with reference to the following examples. However, the following examples are intended to illustrate the invention and should not be construed as limiting the scope of the invention.

The following example was prepared foamed concrete while varying the content of the foaming agent. This is due to the nature of the bubbles produced in the bubble group (30 liters of foaming agent solution) generating bubbles. This is because the sound absorbing material absorbs the negative wavelength only when the continuity (which must be followed) of the fine bubbles is high, unlike the sound insulating material. That is, in order to secure the continuity of the bubbles, bubbles must be deflected to some extent during curing of the concrete composition. The sound absorbing material reflects sound, but the sound absorbing material absorbs sound, and the longer the bubble in the sound absorbing surface, the longer the absorbed sound can be dissipated as heat energy.

Example  One

The powder slurry was prepared by mixing materials as shown in Table 1. A powder solvent was prepared by adding a mixed solvent of 139.9 kg of water and 1.84 kg of a naphthalene-based water reducing agent to the dry powder blended mixture at the blending ratios of Table 1. In this case, the amount of water added corresponds to about 70 parts by weight based on the total weight of the powder, excluding the bottom ash. As a foaming agent, 0.64 kg of alkyl ether sulfate ester salt was diluted with 30 L of water to make a bubble group using a bubble generator, and then 714 L of the bubbles were injected and mixed with the powder slurry in a ribbon mixer for 2 minutes. After filling the powder slurry in a mold for 4 hours at room temperature for air curing and steam curing at 80 ° C. for 3 hours, and then taken out of the curing machine and again in a high temperature and high pressure steam curing in an autoclave and using a dryer It was dried so that the moisture content was 10 ± 2%.

The lightweight foamed concrete was cut to a size of 10 × 10 × 10cm, and then the physical properties such as dry weight, compressive strength, and sound absorption rate of vertical incident sound were measured.

The specific dry weight is obtained by dividing the weight measured after completely drying the foamed concrete at 100 ℃. The specific dry weight and compressive strength were measured according to KS F 4914.

The sound absorption rate was measured according to KS F 2814 as a vertical incident sound absorption rate measurement method. Generally, when the average sound absorption rate is 0.60, it is evaluated as an excellent sound absorption material.

Table 2 shows the measurement results of the physical properties and the sound absorption rate.

Example  2

Foamed concrete was prepared in the same manner as in Example 1 except that 80 parts by weight of water for preparing a slurry was added to 100 parts by weight of powder except bottom ash. With respect to the prepared foam concrete, the specific dry weight, compressive strength, and sound absorption rate of vertical incident sound were measured in the same manner as in Example 1, and the results are shown in Table 2.

Example  3

Foamed concrete was prepared in the same manner as in Example 2, except that 0.64 kg of the foaming agent was diluted with 30 L of water to make a group of bubbles. With respect to the prepared foam concrete, the specific dry weight, compressive strength, and sound absorption rate of vertical incident sound were measured in the same manner as in Example 1, and the results are shown in Table 2.

Example  4

Foamed concrete was prepared in the same manner as in Example 2 except that 0.96 kg of the foaming agent was diluted with 30 L of water to make a group of bubbles. With respect to the prepared foam concrete, the specific dry weight, compressive strength, and sound absorption rate of vertical incident sound were measured in the same manner as in Example 1, and the results are shown in Table 2.

Example  5

Foamed concrete was prepared in the same manner as in Example 1 except that 90 parts by weight of the water for preparing the slurry was added to 100 parts by weight of powder except bottom ash, and 0.64 kg of the foaming agent was diluted with 30 L of water to form a bubble group. With respect to the prepared foam concrete, the specific dry weight, compressive strength, and sound absorption rate of vertical incident sound were measured in the same manner as in Example 1, and the results are shown in Table 2.

In the above embodiment, even if bubbles were formed by incorporating the same foaming agent, that is, a foaming solution of 30 liters of foaming agent, the continuity of the bubbles may vary greatly depending on how much water is added later. This is because if they are not defoamered, the bubbles are independent of each other to exhibit the properties of the sound absorbing material. Therefore, it is possible to check the content range of the water to be bubbled at an appropriate level by changing the input amount of water in the slurry having the foaming bubble.

Example  6

Foamed concrete was prepared in the same manner as in Example 5 except that 0.96 kg of the foaming agent was diluted with 30 L of water to form a foam group. With respect to the prepared foam concrete, the specific dry weight, compressive strength, and sound absorption rate of vertical incident sound were measured in the same manner as in Example 1, and the results are shown in Table 2.

Comparative example  One

The reverberation chamber method sound absorption rate was measured using glass fiber of surface density 32K thickness 50mm currently commercialized as the comparative example 1, and the result is shown in Table 2.

division Compounding ratio (kg / m ³ standard) Bubble (ℓ) water Plain portland cement Alumina cement Slaked lime Anhydrous gypsum Bottom ash High performance water reducer Foam Example One 139.9 167.1 16.7 6.0 10.0 159.9 1.84 0.64 714 2 149.4 156.2 15.6 5.6 9.4 149.4 1.72 0.32 714 3 149.4 156.2 15.6 5.6 9.4 149.4 1.72 0.64 714 4 149.4 156.2 15.6 5.6 9.4 149.4 1.72 0.96 714 5 157.8 146.6 14.7 5.3 8.8 140.3 1.61 0.64 714 6 57.8 146.6 14.7 5.3 8.8 140.3 1.61 0.96 714 Comparative example One glass fiber

division Weight ratio Compressive strength (MPa) Sound absorption NRC 125 250 500 1000 2000 4000 Example One 0.27 1.18 - 0.42 0.73 0.99 0.85 - 0.75 2 0.30 1.28 - 0.53 0.84 0.71 0.81 - 0.72 3 0.26 1.26 - 0.64 0.85 0.76 0.82 - 0.76 4 0.29 1.09 - 0.40 0.81 0.94 0.85 - 0.75 5 0.26 1.22 - 0.67 0.74 0.70 0.77 - 0.72 6 0.27 1.03 - 0.42 0.76 0.98 0.82 - 0.75 Comparative example One - - 0.3 0.45 0.80 0.85 0.75 0.80 0.71

As shown in the results of Table 2, the lightweight foam concrete product for sound absorbing material according to the present invention was developed to solve the durability, fire resistance, and environmental shortcomings of the existing sound absorbing material product. The specific gravity is 0.4 ± 0.1 and the compressive strength is 10kgf. / cm ² In addition to the above, the sound absorption rate is not only 0.70 or more, but also to produce a product superior in adhesion to other products made of the same material as the concrete base material.

As described above, the lightweight foamed concrete product manufactured according to the present invention has a very good sound absorption rate of more than NRC 0.7 compared to the existing sound absorbing products, and because the constituent material is due to the hydration reaction of inorganic powders, it is not only excellent in heat resistance and water resistance. In case of fire, it does not burn, maintains its original shape, and its performance does not change. In addition, it is possible to produce economically compared to the existing sound absorbing products.

Claims (5)

Powder containing 40 to 50 parts by weight of bottom ash fine powder, 40 to 50 parts by weight of ordinary Portland cement and 2 to 10 parts by weight of alumina cement, 2 to 10 parts by weight of anhydrous gypsum and 1 to 5 parts by weight of slaked lime, based on the total weight of powder 100; 70 to 90 parts by weight of water based on the weight of the powder except for the bottom ash 100; And Containing bubbles in a volume ratio of 200 to 300 with respect to the total volume 100 of the powder slurry consisting of the powder and water, Wherein the bubble is a foaming lightweight foam concrete composition for a sound absorbing material, characterized in that the dilution of the alkyl ether sulfate ester salt with water to 2 to 4% by weight prepared by the foaming method. According to claim 1, wherein the bubble is 0.3 ~ 1.4mm in size, the average bubble size is 1.2mm, lightweight foam concrete for sound-absorbing material, characterized in that to maintain a porosity of 50 to 80%, soft porosity 10 to 40% Composition. Preparing a powder mixture by dry-beaming cement, alumina cement, hydrated lime and anhydrous gypsum in a bottom ash powder for 1 to 2 minutes; Preparing a powder slurry by mixing a mixed solution of water and a water reducing agent previously mixed with the powder mixture mixed by the dry beam; Preparing a powder bubble slurry by mixing bubbles in the powder slurry; Pre-curing step of injecting the powder bubble slurry into a mold for 3 to 4 hours air curing at room temperature, and steam curing for 4-6 hours at 60 ~ 80 ℃ after the air curing step; And After the pre-cure step 150 to 180 ℃, including the step of steam curing for 8 to 10 hours at a high temperature and high pressure of 8 to 10 atm, Bubbles mixed in the powder bubble slurry step is a lightweight foamed concrete manufacturing method, characterized in that produced by the pre-foaming method by adding 2 to 4% by weight of the surfactant. The method of claim 1, wherein the lightweight foam concrete has a relative specific gravity of 0.4 ± 0.1, 10kgf / cm ² compressive strength Above, the sound absorption rate is 0.70 or more, the bubble size of 0.3 ~ 1.4mm, the average bubble size of 1.2mm, and maintains the porosity 50 ~ 80%, soft porosity 10 ~ 40% of the lightweight foam concrete for sound-absorbing material Manufacturing method. Light-weight foam concrete sound absorbing material produced by the method of claim 3 or 4.

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