JPH10263390A - Pollutant removal member and method of manufacturing the same - Google Patents

Abstract

[PROBLEMS] To be able to manufacture easily and inexpensively, suitable for treatment of flue gas and exhaust gas in a car tunnel, and to be able to effectively use used waste as fertilizer. The substance removing member is obtained by pulverizing a hardened material of a slurry containing a foam obtained from a calcareous raw material, a siliceous raw material, a foaming agent, a foaming stabilizer, and titanium dioxide. Cement can be used instead of the raw material. The hardened body containing cement may contain quicklime. In the production method of the present invention, water, a foaming agent, a foaming stabilizer and titanium dioxide are mixed to form a titanium dioxide mixed slurry, and a calcareous material and a siliceous material are added to the slurry to form a bubble mixed slurry. Then, after curing, the obtained cured product is pulverized. Curing is room temperature curing, steam curing or autoclave curing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contaminant removing member and a method for manufacturing the same, and more particularly, the present invention relates to flue gas and CO, SOx,
The present invention relates to a pollutant removing member suitable for treating exhaust gas containing NOx and the like and capable of effectively using used waste as a fertilizer, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, exhaust gas regulations for factories, automobiles, and the like have been defined by environmental standards, and the concentration of sulfur dioxide and NOx in the air has been reduced. For example, in a tunnel or the like, a high concentration of pollutants is present. In recent years, the use of a photocatalyst, particularly titanium dioxide, has been disclosed as a method for removing such contaminants, and various applied products using the titanium dioxide have been developed. As such an example, Japanese Unexamined Patent Publication No. 6-327965 specifically discloses that a hydrated aggregate of a hydraulic compound has a forbidden band width of 0.5 to 5 eV as a remover of harmful substances such as ethylene. A harmful substance remover obtained by dispersing a semiconductor (for example, titanium dioxide or the like) is disclosed. JP-A-7-171408 discloses that a photocatalyst particle is adhered to a substrate via a hardly decomposable binder. A photocatalyst is disclosed. Further, JP-A-8-2434
No. 02 discloses a photocatalytic material in which part or all of titanium oxide and an oxidation promoter are present on the surface of an inorganic cured product. These are all used for removing harmful substances. From the viewpoint of removal of exhaust gas, there is a ceramic filter which is fired at a high temperature of 1000 ° C. or more using silica-alumina as a raw material.

[0003]

However, as described above, the harmful substance removing agent described in JP-A-6-327965 is intended to remove mercaptans, ammonia, hydrogen sulfide, and ethylene. 7-1714
No. 08 discloses that the photocatalyst is effective against methyl mercaptan, aldehyde and NOx. Furthermore, the photocatalyst material described in JP-A-8-243402 has been shown to exhibit an organic odor-eliminating effect, but has a problem in that the decomposed product is acidic and therefore is not environmentally desirable. . Further, ceramic filters are not practical in that they are expensive in terms of cost.

Accordingly, the present inventors have focused on the purification performance of titanium dioxide in the photocatalyst as described above, and have variously studied the point that CO or CO ₂ , SOx, NOx, etc. contained in exhaust gas are simultaneously and effectively removed. When examined, the cement-based material acts as an alkali neutralizer and fixes the sulfur dioxide in consideration of the fact that the porous body of the cement-based material is preferable for removing the contaminants. The present invention has been made based on the above.
Therefore, the first problem to be solved by the present invention is:
Flue gas and CO, SO emitted by automobiles in tunnels
An object of the present invention is to provide a pollutant removing member suitable for treating exhaust gas containing x, NOx and the like and capable of effectively using used waste as fertilizer. A second object of the present invention is to provide a method of manufacturing a pollutant removing member which can be manufactured easily and inexpensively and has excellent exhaust gas purification performance.

[0005]

The above objects of the present invention are attained by the following inventions.

(1) calcareous material, siliceous material, foaming agent,
A contaminant removing member obtained by pulverizing a cured product of a foam-containing slurry obtained from a foam stabilizer and titanium dioxide. (2) The contaminant removing member according to (1), wherein cement is used instead of the calcareous raw material and the siliceous raw material. (3) The contaminant removing member according to (2), wherein the hardened body containing cement contains quicklime. (4) The contaminant removing member according to any one of (1) to (3) above, wherein the cured body has been subjected to steam curing or autoclave curing. (5) The contaminant removing member according to any one of (1) to (4) above, wherein the cured body is a porous calcium silicate. (6) The contaminant removing member according to any one of (1) to (5), wherein the size of the pulverized product of the cured product is 1 to 7 mm. (7) Water, a foaming agent, a foaming stabilizer and titanium dioxide are mixed to form a titanium dioxide mixed slurry, and a calcareous raw material and a siliceous raw material are added to the slurry to form a bubble mixed slurry, which is then cured. Thereafter, the obtained cured product is pulverized, thereby producing a contaminant removing member. (8) The method for producing a contaminant removing member according to (7), wherein the curing is any of room temperature curing, steam curing, and autoclave curing. (9) The method for producing a contaminant removing member according to the above (7) or (8), wherein cement is used instead of the calcareous raw material and the siliceous raw material. (10) The method for producing a contaminant removing member according to the above (7) or (8), wherein the cured product is a calcium silicate porous material.

The contaminant-removing member of the present invention is obtained by pulverizing a cured product of an aerated slurry obtained from a calcareous material, a siliceous material, a foaming agent, a foam stabilizer and titanium dioxide. Thereby, an excellent effect of effectively removing carbon monoxide, sulfur dioxide, nitrogen oxides, and the like defined in the environmental standards is exhibited. In the present invention, hydrates in a cement hardened body, for example, slaked lime, react with carbon monoxide or carbon dioxide in the air by using cement instead of the calcareous raw material and the siliceous raw material, and calcium carbonate and silicate gel. The silica gel remains as a skeleton of the hydrate and adsorbs sulfur dioxide, nitrogen oxides and the like. Therefore, an excellent effect that carbon monoxide, sulfur dioxide, nitrogen oxide and the like can be more effectively removed is exhibited. Further, since the hardened body containing the cement contains quicklime, carbon monoxide or carbon dioxide can be more effectively removed.

The cured product of the present invention has been subjected to steam curing or autoclave curing, whereby the curing of the porous body can be promoted and the strength can be further increased. On the other hand, in the present invention, the used contaminant-removing member is preferably used as a fertilizer, as well as having a contaminant-removing action when the cured body is a calcium silicate porous body or a cement-based porous body. The size of the pulverized product of the cured product is preferably 1 to 7 mm, so that the removal rate is large as a contaminant removing member, which is not only effective but also preferable when the used component is used as a fertilizer. That's it.

The method for producing a contaminant removing member of the present invention comprises:
Water, a foaming agent, a foaming stabilizer and titanium dioxide are mixed to form a titanium dioxide mixed slurry, and a calcareous raw material and a siliceous raw material are added to the slurry to form a bubble mixed slurry, which is then cured and then obtained. The obtained cured product is pulverized, and titanium dioxide adheres to the surface of the bubbles and is uniformly dispersed by such a production method. Further, in the production method of the present invention, after forming the bubble-containing slurry, curing is performed,
This curing is preferably performed at room temperature curing, steam curing or autoclave curing. In particular, a preferable product having accelerated curing and developed strength is obtained by autoclaving.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below, but the present invention is not limited thereto.

Examples of the calcareous raw material used in the present invention include lime (quick lime, slaked lime, lime plaster, lime mortar, etc.) and cement.
Examples include silica sand, silica stone, blast furnace slag, and the like. When these raw materials are added with a foaming agent and a foaming stabilizer, and further supplemented with titanium dioxide and autoclaved, a so-called porous calcium silicate can be obtained. In addition, cement can be used in place of these raw materials, and in this case, a porous cement body can be obtained. As the cement, for example, ordinary Portland cement, early-strength Portland cement, moderate heat Portland cement, ultra-high-strength Portland cement, sulfate-resistant Portland cement, white Portland cement, blast furnace cement, fly ash cement, silica cement, alumina cement, magnesia Cement, ultra-rapid hardening cement, and the like.

The titanium dioxide used in the present invention is a kind of semiconductor substance. As the titanium dioxide, either an anatase type titanium dioxide powder or a rutile type titanium dioxide powder can be used. Titanium powder is preferred. Titanium dioxide has a finer particle diameter than that of fine particles, and a better effect of removing harmful substances can be obtained.
One having a thickness of 00 nm is used.

[0013] The amount of titanium dioxide contained in the contaminant removing member of the present invention is 5 to 70 parts by weight of titanium dioxide based on 100 parts by weight of the contaminant removing member. Preferably, the amount is 10 to 50 parts by weight of titanium dioxide with respect to 100 parts by weight of the contaminant removing member. When the amount of titanium dioxide is less than 5 parts by weight, there is no effect on the contaminant removal performance, and when the amount of titanium dioxide exceeds 70 parts by weight, it is practically economically disadvantageous.

In the present invention, an oxidizing agent can be added to promote the effect of removing the contaminants of the titanium dioxide. Examples of the oxidizing agent include transition metals, noble metals, rare earth elements, and oxides. , Hydroxides, halides and salts. As the salts, sulfates, nitrates, phosphates, carbonates and the like are preferable. Specifically, Ni, Cr, Fe, Z
n, Ti, Mn, Co, Mo, V, Sr, W, Pd, C
u, Au, Ag, Pt, La, Ce, Pr, Nd, D
simple substance of y, Ho, Er, Ru, Rh and Lu, an oxide,
Examples include at least one selected from the group consisting of hydroxides, halides and salts, and further include iron sulfate, silver nitrate, and the like. By using these oxidation promoters, the contaminant removal performance can be further improved.

The foaming agent used in the present invention is used for forming bubbles by being added to the above-mentioned calcareous material and siliceous material, or cement. An activator or the like is used. As surfactants, synthetic surfactant systems include carboxylate, sulfate, sulfonate (eg, sodium alkylbenzene sulfonate), phosphate, primary to tertiary amine salts, Examples include quaternary ammonium salts, amino acid type, betaine type, polyethylene glycol type (for example, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkylphenol ether sulfate, etc.), polyhydric alcohol type and the like.

The resin soap system includes rosin soap and rosin maleate soap. In addition, the hydrolyzed protein system includes partially degraded proteins of natural animals and plants. The amount of the foaming agent used in the present invention is 10
The amount is 0.001 to 5 parts by weight, preferably 0.005 to 0.5 parts by weight with respect to 0 parts by weight. Further, the foaming stabilizer used in the present invention can stabilize the bubbles in the cured product of the obtained bubble mixture.
As the foam stabilizer, a water-soluble polymer is preferable, and examples thereof include polyvinyl alcohol, methyl cellulose, and polyacrylate. The addition amount of these foam stabilizers is 0.01 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the whole raw materials.

The method for producing a contaminant removing member of the present invention comprises:
A foaming agent, a foaming stabilizer and titanium dioxide were added to water and mixed to obtain a slurry mixed with titanium dioxide. Further, a calcareous raw material and a siliceous raw material are added to this slurry to form an aerated slurry, and after curing, the obtained cured product is pulverized.
It is preferred to carry out either steam curing or autoclave curing. In particular, a preferable product having accelerated curing and developed strength is obtained by autoclaving. At this time,
The porous hardened body composed of calcium silicate is produced by foaming a calcareous raw material and a siliceous raw material with metal aluminum or a surfactant or the like, and then autoclaving. In addition, in the present invention, when a foaming agent is added to the cement and foamed, a cement-based porous body is formed and cured to form a cured body, whereby a material having excellent curing acceleration and strength can be obtained.

In the present invention, when curing the porous body, aerial curing which is generally known in this technical field can be performed. In this aerial curing, the obtained porous body is left as it is for one day or more. Preferred number of days left
15 days. In the case of steam curing, high-temperature steam is sent to a curing room, and the temperature is 40 ° C. to 85 ° C. and the curing time is 2 hours to 36 hours under atmospheric pressure. At this time, the heating rate is 12 ° C / h to 33 ° C / h, and the maximum temperature is 60 ° C to 75 ° C.
Is preferred. Preliminary time until steam curing is 1 hour ~
12 hours is desirable. This curing can be repeated as needed. Further, when performing autoclave curing, the porous body is sent to the autoclave chamber, and the temperature is reduced to 15 ° C.
The curing is performed at 0 ° C. to 200 ° C. for a curing time of 2 hours to 10 hours. At this time, the heating rate is 50 ° C./h to 80 ° C./h, and the maximum temperature is preferably 170 ° C. to 190 ° C. This curing can be repeated as needed.

In the present invention, the manufacturing method of the contaminant removing member is most preferably the above-described manufacturing method. In addition, a calcareous material, a siliceous material, a foaming agent and a foam stabilizer are mixed. Titanium dioxide is added to this mixture to form a bubble-containing slurry, and after curing, the obtained cured product may be pulverized, or a calcareous material, a siliceous material,
A method in which titanium dioxide, a foaming agent and a foaming stabilizer are uniformly mixed once, the resulting aerated slurry is cured, and then the cured porous body is pulverized. The size of the contaminant removing member is preferably set to an appropriate size in the range of 1 mm to 7 mm, more preferably 1 mm to 5 mm.
mm. The pulverized material of the contaminant removing member thus obtained is put in an appropriate container and installed in a tunnel or a place with a lot of contaminants for use.

When the contaminant removing member of the present invention is used in a tunnel, carbon monoxide and carbon dioxide are removed by a cement-based porous member or a calcium silicate porous member by using together with an ultraviolet lamp. Since nitrogen oxides and nitrogen oxides are not only adsorbed on the porous body but also decomposed and removed by the catalytic action of titanium dioxide under ultraviolet rays, in the present invention, all of these contaminants are simultaneously removed. Since the used contaminant removing member can be used as a fertilizer, it does not need to be disposed of and is environmentally preferable. Further, when used, the used contaminant removing member has a particle size of 1 to 7 mm, which is preferable in that it can be used as it is.

The contaminant removing member of the present invention can effectively remove carbon monoxide, carbon dioxide, sulfur dioxide, nitrogen oxides and the like as described above. In addition, mercaptans, ammonia, hydrogen sulfide, amines It is needless to say that ethylene and the like can be removed. Further, the contaminant removing member of the present invention also has a water purification effect on contaminated water contaminated with water, and exhibits an excellent purification effect when brought into contact with contaminated water in an appropriate form. When the hardened body containing cement contains quicklime, carbon monoxide or carbon dioxide can be more effectively removed.

[0022]

The hydrate and slaked lime formed by hydration in the cement-based porous member or calcium silicate porous body of the present invention react with carbon monoxide and carbon dioxide to decompose into calcium carbonate and silicate gel. This silica gel remains as a hydrate skeleton and adsorbs nitrogen oxides and sulfur dioxide. In addition, since it contains titanium dioxide, in the dark, by using an ultraviolet lamp together, this titanium dioxide decomposes nitrogen oxides and sulfurous acid gas under ultraviolet rays to generate sulfate ions and nitrate ions and is absorbed in the cured product .

Further, in the contaminant removing member of the present invention, bubbles are formed by the foaming agent to form a porous body, and the porous body effectively absorbs the contaminants. By setting the size of the contaminant removing member to 1 to 7 mm, the surface area of the contaminant removing member can be increased to increase the adsorption efficiency. Further, in the present invention, the obtained porous body is cured and cured, but the curing can promote the curing and develop the strength.

[0024]

The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 Anionic surfactant in 50 parts by weight of water, trade name: D-3-D, Kao Corporation 0.01
Parts by weight and 0.5 parts by weight of polyvinyl alcohol are mixed to form a foam slurry, and then 10 parts by weight of titanium dioxide powder (manufactured by Ishihara Sangyo Co., Ltd.) is added and mixed to form a slurry mixed with titanium dioxide. did. On the other hand, quicklime 50
Parts by weight and 50 parts by weight of porazone were sufficiently mixed to produce a uniform mixture, and this was added to the slurry and mixed to produce a bubble-containing slurry. The obtained slurry was left as it was for 24 hours to produce a cured product. The obtained cured product was dried and pulverized to 4 mm or less to obtain a contaminant removing member. This contaminant removal member was placed in a container containing a mixture of carbon monoxide, carbon dioxide, sulfur dioxide and nitrogen oxides, and allowed to stand under ultraviolet light for 24 hours, and the state of removal of the contaminants in the container was measured. All contaminants were adsorbed. Then, the used contaminant removing member could be used as a siliceous fertilizer also serving as a nitrogen fertilizer.

Example 2 In place of the method for producing a bubble-containing slurry described in Example 1, 50 parts by weight of quicklime and 50 parts by weight of porazone were sufficiently mixed to form a uniform mixture, while 50 parts by weight of water were used. Anionic surfactant in the part, trade name: D
-3-D, Kao Corporation) 0.01 parts by weight and 0.5 parts by weight of polyvinyl alcohol are mixed to form a foam slurry, and then the above mixture is added thereto, and the mixture is stirred to form a bubble-containing substance. , A contaminant-removing member is manufactured in the same manner as in Example 1 except that 10 parts by weight of titanium dioxide powder (manufactured by Ishihara Sangyo Co., Ltd.) is further added and mixed to manufacture a bubble-containing slurry. Then, when the test was performed in the same manner as in Example 1, substantially all of the contaminants were adsorbed. Then, the used contaminant removing member could be used as a siliceous fertilizer also serving as a nitrogen fertilizer.

Example 3 Quicklime 50 described in Example 1
White cement 1 instead of 50 parts by weight of Porazone
A contaminant removing member was manufactured in the same manner as in Example 1 except that 00 parts by weight was used, and tested in the same manner as in Example 1. As a result, substantially all of the contaminants were adsorbed. Then, the used contaminant removing member could be used as a siliceous fertilizer also serving as a nitrogen fertilizer. Also, the water purification effect was excellent.

Example 4 100 parts by weight of white cement,
Anionic surfactant in 50 parts by weight of water, trade name: D-3
-D, Kao Corporation) 0.01 parts by weight and 0.5 parts by weight of polyvinyl alcohol were mixed and stirred to form air bubbles, and then titanium dioxide powder (Ishihara Sangyo Co., Ltd.)
After adding and mixing 10 parts by weight, the mixture was carried into an autoclave chamber and cured at a temperature of 179 ° C. (12 kgf / cm ² ) and a curing time of 5 hours. The obtained cured product is dried and then 4 m
m or less to obtain a contaminant removing member. When tested in the same manner as in Example 1, it was found to have excellent contaminant removal performance. When the used contaminant removing member was used as a fertilizer, the effect of a siliceous fertilizer also serving as a nitrogen fertilizer was obtained.

[0029]

The contaminant removing member of the present invention is obtained by pulverizing a cured product of a slurry containing bubbles obtained from a calcareous material, a siliceous material, a foaming agent, a foaming stabilizer and titanium dioxide. As a result, it is possible to effectively remove contaminants such as carbon monoxide, carbon dioxide, sulfur oxides, nitrogen oxides and the like specified in environmental standards, and to have an excellent effect of having an excellent water purification effect. It is. Further, in the present invention, carbon monoxide, carbon dioxide, sulfur oxides, nitrogen oxides, etc. are more effectively removed by hydrates in the cement hardened body by using cement instead of calcareous raw materials and siliceous raw materials. It has an excellent effect of having an excellent water purification effect as well as being able to do so. Further, since the hardened body containing the cement contains quicklime, carbon monoxide or carbon dioxide can be more effectively removed.

The cured product of the present invention has been subjected to steam curing or autoclave curing, whereby the curing of the porous body can be promoted and the strength can be further increased. On the other hand, in the present invention, the used contaminant-removing member is preferably used as a fertilizer, as well as having a contaminant-removing action when the cured body is a calcium silicate porous body or a cement-based porous body. In addition, by setting the size of the pulverized product of the cured product to a particle size of 1 to 7 mm, the removal rate is high even as a contaminant removal member, and it is effective.

The method for producing a contaminant removing member according to the present invention comprises:
Water, a foaming agent, a foaming stabilizer and titanium dioxide are mixed to form a titanium dioxide mixed slurry, and a calcareous raw material and a siliceous raw material are added to the slurry to form a bubble mixed slurry, which is then cured and then obtained. The obtained cured product is pulverized, and titanium dioxide adheres to the surface of the bubbles and is uniformly dispersed by such a production method. Further, in the production method of the present invention, after forming the bubble-containing slurry, curing is performed,
As this curing, any one of normal temperature curing, steam curing and autoclave curing can be used to obtain a preferable one which has accelerated curing and has developed strength.

Claims (10)

[Claims] 1. A contaminant removing member obtained by pulverizing a cured product of a bubble-containing slurry obtained from a calcareous raw material, a siliceous raw material, a foaming agent, a foaming stabilizer and titanium dioxide. 2. The contaminant removing member according to claim 1, wherein cement is used in place of the calcareous raw material and the siliceous raw material. 3. The contaminant removing member according to claim 2, wherein the hardened body containing cement contains quicklime. 4. The contaminant removing member according to claim 1, wherein the cured body is subjected to steam curing or autoclave curing. 5. The contaminant removing member according to claim 1, wherein the cured body is a calcium silicate porous body. 6. The contaminant removing member according to claim 1, wherein the size of the pulverized cured product is 1 to 7 mm. 7. A mixture containing water, a foaming agent, a foaming stabilizer and titanium dioxide to form a slurry mixed with titanium dioxide, and a calcareous raw material and a siliceous raw material are added to the slurry to form a slurry mixed with bubbles. A method for producing a contaminant removing member, comprising crushing the obtained cured product after curing. 8. The method for producing a contaminant removing member according to claim 7, wherein the curing is one of room temperature curing, steam curing and autoclave curing. 9. The method for producing a pollutant removing member according to claim 7, wherein cement is used in place of the calcareous raw material and the siliceous raw material. 10. The method for producing a contaminant removing member according to claim 7, wherein the cured body is a calcium silicate porous body.