KR102249025B1 - A method of manufacturing foamed concrete aggregate capable of adsorbing and removing precursors in the atmosphere - Google Patents

Abstract

When the foamed concrete aggregate is manufactured, a component that adsorbs the first precursor material in the atmosphere is mixed, and a component that adsorbs the second precursor material in the atmosphere is coated on the foamed concrete aggregate with a component that adsorbs the second precursor material in the atmosphere. Disclosed is a method for producing a foamed concrete aggregate having excellent efficiency in reducing fine dust and atmospheric precursors because it is coated on the surface and voids of the foamed concrete aggregate and is not separated for a long time. The present invention comprises the steps of: (a) mixing a binder with a component that adsorbs the first precursor material in the atmosphere to prepare aerated concrete; (b) crushing the aerated concrete to prepare an aggregate; And (c) coating the aggregate with a component that adsorbs the second precursor material in the atmosphere.

Description

A method of manufacturing foamed concrete aggregate capable of adsorbing and removing precursors in the atmosphere

The present invention relates to a method of manufacturing a foamed concrete aggregate, and more particularly, to a method of manufacturing a foamed concrete aggregate capable of adsorbing and removing precursors in the atmosphere.

It is known that serious diseases such as respiratory diseases are caused by fine dust such as various volatile organic compounds, nitrogen oxides, and ultrafine dust contained in the air. In this context, various studies are also being conducted on the method of imparting the function of reducing harmful substances to concrete structures by applying materials that can be reduced.

Among them, research to utilize a photocatalyst capable of decomposing various organic substances and microorganisms by light is drawing attention, but research and development are insufficient until practical use.

Korean Registered Patent No.1022413 states that by adding a porous material to the body of the block, it has warmth, sound insulation, deodorization, antibacterial properties, and far-infrared radiation functions in the air, and has water-retaining properties, adsorption or filtration functions in water Since the surface of the block is coated with a water-curable composition containing a photocatalyst, a functional concrete block has been disclosed that simultaneously purifies the atmosphere and purifies water by the function of decomposing organic matter, but the adsorption of nanostructures using aerated concrete aggregate It is not described.

Therefore, the present invention was conceived to solve the above problems, mixing a component that adsorbs the first precursor material in the atmosphere when manufacturing a foamed concrete aggregate, and coating the component that adsorbs the second precursor material in the atmosphere to the foamed concrete aggregate. By doing so, a component that adsorbs the second precursor material in the atmosphere is coated on the surface and voids of the foamed concrete aggregate and is not separated for a long time, thereby providing a method of manufacturing a foamed concrete aggregate having excellent efficiency in reducing fine dust and atmospheric precursors.

In order to solve the above problems, the present invention comprises the steps of: (a) preparing a foamed concrete by mixing a component that adsorbs the first precursor material in the atmosphere into a binder; (b) crushing the aerated concrete to prepare an aggregate; And (c) coating the aggregate with a component that adsorbs the second precursor material in the atmosphere.

In addition, in the step (a), the first precursor material in the atmosphere is a carbon oxide. It provides a method for producing a foamed concrete aggregate.

In the step (a), the components that adsorb the first precursor material in the atmosphere are calcium minerals such as Alite (C ₃ S), Belite (C ₂ S), Celite (C ₃ A) and Ferrite (C ₄ AF). It provides a method for producing a foamed concrete aggregate, characterized in that at least one selected from the group consisting of.

In addition, in the step (a), the component adsorbing the first precursor material in the atmosphere is 5 to 50 parts by weight based on 100 parts by weight of the binder. It provides a method for producing a foamed concrete aggregate.

In addition, in the step (a), the foamed concrete provides a method of manufacturing a foamed concrete aggregate, characterized in that the foaming ratio is 40 to 80%.

In addition, the aggregate in the step (b) provides a method for producing a foamed concrete aggregate, characterized in that the diameter of the particles is 1 ~ 40mm.

In addition, in step (c), the second precursor material in the atmosphere is at least one selected from the group consisting of nitrogen oxides and sulfur oxides.

In addition, in the step (c), the component adsorbing the second precursor material in the atmosphere is a nanostructured powder, which provides a method for producing a foamed concrete aggregate.

In addition, the nanostructure is TiO ₂ , ZnO, SnO ₂ , CdS, ZrO ₂ , V ₂ O ₃ , WO ₃ and In ₂ O _{3 The} method for producing a foamed concrete aggregate, characterized in that at least one selected from the group consisting of to provide.

In addition, the nanostructured powder provides a method for producing a foamed concrete aggregate, characterized in that the diameter of the particles is 50 ~ 200um, the content is 0.001 ~ 5 parts by weight relative to 100 parts by weight of the binder.

In addition, the coating in step (c) provides a method for producing a foamed concrete aggregate, characterized in that the coating is carried out for 0.5 to 24 hours.

In the present invention, in a method for producing a foamed concrete aggregate, when the foamed concrete aggregate is manufactured, a component that adsorbs a first precursor material in the atmosphere is mixed, and the foamed concrete aggregate is coated with a component that adsorbs a second precursor material in the atmosphere. A component that adsorbs the second precursor material in the atmosphere is coated on the surface and voids of the foamed concrete aggregate and is not separated for a long time, so that it is possible to provide a method of manufacturing a foamed concrete aggregate having excellent efficiency in reducing fine dust and atmospheric precursors.

1 is a conceptual diagram showing a foamed concrete aggregate according to a method of manufacturing a foamed concrete aggregate according to an embodiment of the present invention,
2 is a photograph showing a foamed concrete aggregate manufactured according to the method of manufacturing a foamed concrete aggregate of an embodiment of the present invention,
Figure 3 is a graph showing the NOx and SOx adsorption results of the foamed concrete aggregates prepared in Examples 1 to 4.
Figure 4 is a graph showing the NOx and SOx adsorption results of the foamed concrete aggregates prepared in Comparative Examples 1 to 4.

Hereinafter, a preferred embodiment of the present invention will be described in detail. In describing the present invention, when it is determined that a detailed description of a related known technology may obscure the subject matter of the present invention, a detailed description thereof will be omitted. Throughout the specification, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless otherwise stated.

The present inventors face the fact that serious diseases such as respiratory diseases are caused by fine dust such as various volatile organic compounds, nitrogen oxides, and ultrafine dust contained in the atmosphere, and in order to solve these problems, the contact frequency with the atmosphere is increased. As a result of repeated research on large concrete, it was found that when a nanostructure is coated on aerated concrete, it is possible to adsorb and remove precursors in the atmosphere, and the present invention has been reached.

Accordingly, the present invention comprises the steps of: (a) preparing a foamed concrete by mixing a binder with a first precursor material adsorption component in the atmosphere; (b) crushing the aerated concrete to prepare an aggregate; And (c) coating the aggregate with a second precursor material adsorption component in the air.

1 is a conceptual diagram showing a concrete aggregate according to a method of manufacturing a concrete aggregate according to an embodiment of the present invention, and FIG. 2 is a photograph showing a coated aggregate.

Referring to FIGS. 1 and 2, it can be seen that the nanostructure is coated on the aggregate in which the pores are formed, and fine dust and atmospheric precursors may be adsorbed and removed by the coated nanostructure.

Hereinafter, the manufacturing method according to the present invention will be described in detail.

The step (a) is a step of preparing a foamed concrete having a void so that a component that adsorbs the second precursor material in the atmosphere described later can be coated, and a component that adsorbs the first precursor material in the atmosphere is mixed with a binder. This is the step of manufacturing aerated concrete.

In the step (a), the foamed concrete is prepared by adding water to the binder mixed with the first precursor material adsorption component, and then first moistening the paste to prepare a paste, and a group of bubbles generated by using a bubble generator on the paste. It may be prepared through the step of generating a foam slurry by inputting and secondary wet mixing, and pouring the foam slurry into a mold for curing, but is not limited thereto, and may be prepared by a method generally known in the art.

In the present invention, as the binder in step (a), ocher, blast furnace slag powder, coal ash, gypsum, cement, sand, fly ash, bottom ash, Portland cement, etc. may be used, and in the step (a), compounding As water, water may be used in a conventional amount, but generally 20 to 40% by weight of water is used based on the weight of the binder, and preferably 25 to 35% by weight of water may be used.

In the present invention, the first precursor material in the atmosphere in step (a) may be carbon oxide (COx), and the carbon oxide is carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrous oxide (C ₃ O ₂ ), etc. It may be a carbon oxide of.

In the present invention, the components that adsorb the first precursor material in the atmosphere in the step (a) are calcium minerals such as Alite (C ₃ S), Belite (C ₂ S), and Celite (C). _It may be one or more selected from the group consisting of 3 A) and ferrite (Ferrite, C _{4 AF), and preferably, γ-C 2} S, which is one of the _{belite (C 2 S).}

The γ-C ₂ S (γ-Ca ₂ SiO ₄ ) is a bellite mineral, which is one of clinker minerals, and has a very stable molecular structure. γ-C _{2 S is a powdery material that is generated when β-C 2} S, a bellite mineral, is gradually cooled and volume expansion occurs due to the dusting phenomenon.

In addition, _{unlike β-C 2} S of cement, γ-C ₂ S is not used as a cement compound because it does not react with water, so it is not used as a cement compound. Carbon oxides are removed by generating Vaterite-based CaCO _3. When γ-C ₂ S is incorporated into a cement-based material, it has the effect of densifying the surface portion as the pores are filled due to a rapid reaction with _{CO 2, thereby contributing to blocking performance degradation factors such as salt damage and sulfate and improving compressive strength.}

[Formula 1]

_{2CaOSiO 2} + 2CO ₂ + 2H ₂ O → 2CaCO ₃ + SiO ₂ + 2H ₂ O

In the present invention, the component adsorbing the first precursor material in the atmosphere in step (a) may be mixed in an amount of 5 to 50 parts by weight based on 100 parts by weight of the binder, and preferably 10 to 30 parts by weight based on the total amount of the foamed concrete. May be mixed in parts by weight.

When the component adsorbing the first precursor material in the atmosphere is mixed in less than 5 parts by weight based on 100 parts by weight of the binder, the carbon oxide adsorption efficiency may be lowered. Compressive strength and flexural strength can be rapidly deteriorated.

In the present invention, bubbles may be added in step (a), and the bubbles may be generally added in a pre-bubble method, but the present invention is not limited thereto.

In addition, the mixing rate of the foam may be 40 to 80%, preferably 50 to 70%, based on the total volume of the foamed concrete in consideration of the decrease in compressive strength and flexural strength.

The bubble mixing ratio represents the ratio of the mixed bubbles to the volume of the total material used and the mixing water.If the bubble mixing ratio is less than 40%, the weight increases and it is difficult to secure the porosity, and when the bubble mixing ratio exceeds 80%, the bubble Settling by defoaming may occur, and in particular, the mechanical properties of the foamed concrete, such as compressive strength and flexural strength, may be rapidly deteriorated.

In the present invention, the aerated concrete may contain 30 to 90% by weight of the Portland cement and 10 to 70% by weight of the coal ash relative to 100% by weight of the total binder, and preferably 40 to 80 of the Portland cement relative to 100% by weight of the total binder. It may contain weight% and 20 to 60% by weight of the coal ash, or the foamed concrete is 10 to 50% by weight of the Portland cement, 20 to 60% by weight of the coal ash and 10 to 50 of the blast furnace slag fine powder relative to 100% by weight of the total binder It may contain weight %, and preferably, the Portland cement 20 to 40% by weight, coal ash 30 to 50% by weight, and 20 to 40% by weight of fine blast furnace slag powder relative to 100% by weight of the total binder may be included.

In the present invention, step (b) is a step for increasing the surface area of the aerated concrete so that it can be easily coated when performing the coating described below, and is a step of crushing the aerated concrete to produce an aggregate.

The diameter of the aggregate particles may be 1 to 40 mm, preferably 2 to 30 mm, more preferably 3 to 20 mm, even more preferably 4 to 15 mm, most preferably It can be 6~13mm.

If the diameter of the aggregate particles is less than 1 mm, the porosity for improving the efficiency of reducing fine dust and atmospheric precursors may be remarkably small, and when the diameter of the aggregate particles exceeds 40 mm, the strength of the foamed concrete for manufacturing them The increase is inevitable, and accordingly, the porosity of the foamed concrete decreases, and as a result, the efficiency of reducing fine dust and atmospheric precursors may decrease.

In the present invention, step (c) is a step of coating a component that adsorbs a second precursor material in the atmosphere to the aerated concrete aggregate in order to reduce fine dust and the second precursor material in the atmosphere.

In the present invention, in the coating, a component that adsorbs the second precursor material in the atmosphere is prepared as a powder and then dissolved in water or alcohol to prepare a solution, and then the aggregate is immersed in the solution or the solution is applied to the aggregate. It can be coated by spraying, and in addition, a component that adsorbs the second precursor material in the atmosphere can be prepared as a powder and coated by a method of directly spraying the aerated concrete aggregate.

In the step (c), the second precursor material in the atmosphere may be at least one selected from the group consisting of nitrogen oxides (NOx) and sulfur oxides (SOx).

The nitrogen oxides are nitrogen monoxide (NO), nitrogen dioxide (NO ₂ ), nitrogen monoxide (N ₂ O), dinitrogen trioxide (N ₂ O ₃ ), dinitrogen tetraoxide (N ₂ O ₄ ), dinitrogen pentoxide ( It may be a nitrogen oxide such as _{N 2} O _{5 ).}

In addition, the sulfur oxide may be a sulfur oxide such as sulfur monoxide (SO), sulfur dioxide (SO ₂ ), and sulfur trioxide (SO _{3 ).}

In the present invention, the second precursor material adsorption component in step (c) may be a nanostructure powder, and the nanostructure is TiO ₂ , ZnO, SnO ₂ , CdS, ZrO ₂ , V ₂ O ₃ , WO ₃ and In ₂ O _{3 It} may be one or more selected from the group consisting of, preferably titanium dioxide (TiO ₂ ).

In the present invention, the diameter of the particles of the nanostructure powder may be 50 to 200um, preferably 100 to 180um, the content of the nanostructure powder may be 0.001 to 5 parts by weight relative to 100 parts by weight of the binder, Preferably it may be 0.005 to 0.1 parts by weight.

When the diameter of the particles of the nanostructured powder is less than 50um or the content is less than 0.001 parts by weight, the nanostructured powder is not easily coated on the surface and voids of the cellular concrete aggregate crushed to the diameter of the predetermined particle The second precursor material adsorption efficiency may be reduced, and when the diameter of the particles of the nanostructure powder exceeds 300 um or the content exceeds 5 parts by weight, the pores of the cellular concrete aggregate crushed to a certain particle diameter are blocked. The efficiency of adsorption of the second precursor material in the air may be lowered.

In the step (c), the coating may be performed for 0.5 to 24 hours, preferably 2 to 20 hours, more preferably 4 to 16 hours.

When the coating is performed for less than 0.5 hours, the coating is not easily performed, so that the efficiency of reducing fine dust and atmospheric precursors may be lowered, and when the coating exceeds 24 hours, the coating efficiency is lowered compared to the time, which is not economical.

In the present invention, a component that adsorbs a second precursor material in the atmosphere by crushing the aggregate into particles having a certain diameter and then coating a component that adsorbs a second precursor material in the atmosphere on the surface and voids of the aerated concrete aggregate. It improved the adsorption and removal efficiency of fine dust and atmospheric precursors than the foamed concrete aggregate prepared by mixing.

As described above, the foamed concrete aggregate produced by using the method for producing a foamed concrete aggregate according to the present invention contains a component that adsorbs the first precursor material in the atmosphere, and is coated with a component that adsorbs the second precursor material in the atmosphere. It can adsorb and remove atmospheric precursors.

Hereinafter, a specific example according to the present invention will be described.

Example One

Portland cement (OPC) 60% by weight and coal ash (CCPs) 40% by weight are mixed to prepare a binder, and _{20 parts by weight of γ-C 2} S relative to 100 parts by weight of the binder are mixed with the binder to dry the mixture, and then the binder A face mold was prepared by adding 30% by weight of water based on the weight and first wet mixing. The bubble group generated by using a bubble generator was added to the face and a second wet mixing was performed to generate a bubble slurry, and the generated bubble slurry was poured into a mold and then cured for 7 days to prepare a bubble concrete having a bubble mixing ratio of 60%. .

The aerated concrete is used in a crusher to prepare an aggregate having an average particle diameter of 6 to 13 mm, and titanium dioxide (TiO _{2 -} ) powder having a particle diameter of 150 μm is added to the aggregate by 0.01 parts by weight compared to 100 parts by weight of the binder. After dissolving in isopropyl alcohol (IPA, 95%), which is 1 part by weight relative to 100 parts by weight of the binder, it is sprayed for 10 hours to coat the aggregate to prepare a foamed concrete aggregate.

Example 2

In Example 1, a foamed concrete aggregate was prepared in the same manner as in Example 1, except that the average diameter of the aggregate particles was 6 to 9 mm.

Example 3

Portland cement (OPC) 30% by weight, coal ash (CCPs) 30% by weight, and blast furnace slag fine powder (GGBS) 40% by weight to prepare a binder, and γ-C ₂ S 20 parts by weight compared to 100 parts by weight of the binder After mixing and drying the mixture, 30% by weight of water was added based on the weight of the binder, and the first wet mixing was performed to prepare a faceplate. The bubble group generated by using a bubble generator was added to the face and a second wet mixing was performed to generate a bubble slurry, and the generated bubble slurry was poured into a mold and then cured for 7 days to prepare a bubble concrete having a bubble mixing ratio of 60%. .

The aerated concrete is used in a crusher to prepare an aggregate having an average particle diameter of 6 to 13 mm, and titanium dioxide (TiO _{2 -} ) powder having a particle diameter of 150 μm is added to the aggregate by 0.01 parts by weight compared to 100 parts by weight of the binder. After dissolving in isopropyl alcohol (IPA, 95%), which is 1 part by weight relative to 100 parts by weight of the binder, it is sprayed for 10 hours to coat the aggregate to prepare a foamed concrete aggregate.

Example 4

In Example 3, a foamed concrete aggregate was prepared in the same manner as in Example 1, except that the average diameter of the aggregate particles was 6 to 9 mm.

Comparative example One

A binder was prepared by mixing 60% by weight of Portland cement (OPC) and 40% by weight of coal ash (CCPs), and _{20 parts by weight of γ-C 2} S relative to 100 parts by weight of the binder was mixed to prepare a mixture. A paste was prepared by mixing 0.01 parts by weight of titanium dioxide (TiO _{2 -} ) with respect to 100 parts by weight of the binder to the mixture to perform dry mixing, and then adding 30% by weight of water based on the weight of the binder, followed by primary wet mixing. A group of bubbles generated using a bubble generator was added to the paste and a second wet mixing was performed to generate a bubble slurry, and the generated bubble slurry was poured into a mold and then cured for 7 days to prepare a bubble concrete having a bubble mixing ratio of 60%. .

The aerated concrete is prepared with an aggregate having an average particle diameter of 6 to 13 mm using a crusher.

Comparative example 2

In Comparative Example 1, a foamed concrete aggregate was prepared in the same manner as in Comparative Example 1, except that the diameter of the aggregate particles was 6 to 9 mm.

Comparative example 3

Portland cement (OPC) 30% by weight, coal ash (CCPs) 30% by weight and blast furnace slag fine powder (GGBS) 40% by weight were mixed to prepare a binder, and γ-C ₂ S 20 parts by weight compared to 100 parts by weight of the binder Prepare the mixture. A paste was prepared by mixing 0.01 parts by weight of titanium dioxide (TiO _{2 -} ) with respect to 100 parts by weight of the binder to the mixture, followed by dry mixing, and then adding 30% by weight of water based on the weight of the binder, followed by primary wet mixing. A group of bubbles generated using a bubble generator was added to the paste and a second wet mixing was performed to generate a bubble slurry, and the generated bubble slurry was poured into a mold and then cured for 7 days to prepare a bubble concrete having a bubble mixing ratio of 60%. .

The aerated concrete is prepared with an aggregate having an average particle diameter of 6 to 13 mm using a crusher.

Comparative example 4

In Comparative Example 3, a foamed concrete aggregate was prepared in the same manner as in Comparative Example 3, except that the average diameter of the aggregate particles was 6 to 9 mm.

Experimental example

In order to investigate the removal characteristics of SOx and NOx of the aerated concrete aggregates prepared in Examples 1 to 4 and Comparative Examples 1 to 4, SOx and NOx adsorption tests were conducted in the following manner using the air quality test method, The results are shown in FIGS. 3 and 4.

[Test Methods]

After placing the aerated concrete aggregate prepared in Examples 1 to 4 and Comparative Examples 1 to 4 into a container having 800 mm (width) × 60 mm (length) × 60 mm (height), the container is placed in the chamber. NOx after 14 hours with a ^{UV lamp (10W/m 2} ) in a state that maintains a constant gas concentration after injecting _{NO 2} and SO ₂ gas into the chamber at 18 to 22°C with 3SLM (Standard Liters per Minute) And SOx gas amount was measured to calculate the removal rate, and the results are shown in FIGS. 3 and 4.

3 and 4, when titanium dioxide is coated on the aerated concrete aggregate (Examples 1 to 4), it can be seen that the adsorption efficiency of NOx is the lowest 49.6% and the highest is 57.6%, and the SOx adsorption efficiency is the lowest. It is 34.8%, the maximum is 52.5%, and the average reduction efficiency is about 1.2 times better than when the diameter of the aggregate is 6 to 9 mm (Examples 2 and 4) is 6 to 13 mm (Examples 1 and 3), and Portland The average reduction efficiency in the case of mixing cement and coal ash (Examples 1 and 2) was 47.9%, and the average reduction efficiency in the case of mixing Portland cement, blast furnace slag powder and coal ash (Examples 3 and 4) was 44.7%. It can be seen that there is no big difference.

On the contrary, in the case of producing aggregate by mixing titanium dioxide during the production of aerated concrete (Comparative Examples 1 to 4), it can be seen that the adsorption efficiency of NOx is the lowest 20.1% and the highest is 23.3%, and the SOx adsorption efficiency is the lowest 10.7. %, and up to 15.7%, compared to the case where titanium dioxide was coated on the aerated concrete aggregate (Examples 1 to 4), the efficiency was significantly lower.

As described above, in the case of a foamed concrete aggregate manufactured according to the method for manufacturing a foamed concrete aggregate according to the present invention, a foamed concrete aggregate is prepared _{by mixing γ-C 2} S, which is a component that adsorbs the first precursor material in the atmosphere when foamed concrete is manufactured. And, by coating the foamed concrete aggregate with titanium dioxide, which is a component that adsorbs the second precursor material in the atmosphere, it is possible to provide a method for manufacturing a foamed concrete aggregate in which the efficiency of reducing fine dust and atmospheric precursors is increased.

The preferred embodiments of the present invention have been described in detail above. The description of the present invention is for illustrative purposes only, and those of ordinary skill in the art to which the present invention pertains will be able to understand that other specific forms can be easily modified without changing the technical spirit or essential features of the present invention.

Claims (11)

(a) mixing a component that adsorbs the first precursor material in the atmosphere to a binder, and preparing a foamed concrete having a foam mixing ratio of 40 to 80% using a bubble generator;
(b) crushing the aerated concrete to prepare an aggregate; And
(c) coating the aggregate with a component that adsorbs a second precursor material in the atmosphere;
As a method for producing a foamed concrete aggregate comprising a,
In the step (a), the first precursor material in the atmosphere is carbon oxide, and the components that adsorb the first precursor material in the atmosphere are calcium minerals Alite (C ₃ S), Belite (C ₂ S), and Celite (C ₃ A) and at least one selected from the group consisting of _{Ferrite (C 4 AF),}
In the step (c), the second precursor material in the atmosphere is at least one selected from the group consisting of nitrogen oxides and sulfur oxides, and the component adsorbing the second precursor material in the atmosphere is TiO ₂ nanostructure powder as the nanostructure. Powder is a method for producing a foamed concrete aggregate having a particle diameter of 50 to 200 um and a content of 0.001 to 5 parts by weight relative to 100 parts by weight of the binder. delete delete The method of claim 1,
In the step (a), the component adsorbing the first precursor material in the atmosphere is mixed with 5 to 50 parts by weight based on 100 parts by weight of the binder. delete The method of claim 1,
In the step (b), the aggregate has a particle diameter of 1 to 40 mm. delete delete delete delete The method of claim 1,
The method for producing a foamed concrete aggregate, characterized in that the coating in step (c) is performed for 0.5 to 24 hours.

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