JP2003047824A - Regeneratable deodorizing filter and method for regenerating the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a safe and inexpensive regeneratable deodorizing filter having a quick deodorizing effect and reusable over a prolonged period of time and to provide a method for regenerating the filter. SOLUTION: A condensed water membrane 2 is formed on the surface of a hygroscopic material 1, water-soluble malodorous gas 3 is dissolved in the water membrane 2 on the surface of the hygroscopic material 1 and the dissolved water-soluble malodorous gas 3, together with the water membrane 2, is washed off. The hygroscopic material 1 is preferably hygroscopic ceramics or hygroscopic fibers and is preferably formed in a honeycomb shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative deodorizing filter and a method for regenerating the deodorizing filter.
For example, a reusable type that enables reuse over a long period by deodorizing air contaminated with odorous gas, especially air contaminated with water-soluble odorous gas, and regenerating the deodorized odorous gas by washing with water. The present invention relates to a deodorizing filter and a method for regenerating the deodorizing filter.

[0002]

2. Description of the Related Art In recent years, indoor air pollution has become a problem as insulation and airtightness of living spaces have been advanced in order to enhance the cooling and heating effects. Sources of indoor air pollution include odorous gases such as cigarette odor, harmful gases such as formaldehyde, and airborne microorganisms such as mold and bacteria. As a means of removing odorous gas, it is common to use an air purifier to circulate contaminated air in the room to deodorize, and the deodorizing methods that have been put to practical use are the activated carbon method, ozone deodorizing method, and photocatalytic method. Etc.

[0003] For example, a deodorizing filter made of activated carbon is installed in an air passage, so that it is possible to quickly adsorb odors in an air stream and has a high deodorizing effect. However, when odorous gas molecules are adsorbed on the pore surface of the activated carbon and the entire pore surface is covered with these molecules, the deodorizing effect is lost and the life ends. The activated carbon method is excellent in deodorizing performance, but is not preferable from the standpoint of economy and global environmental protection because it is disposable.

An ozone deodorizing method is used in which ozone is generated from an ozone generator installed in the air passage to oxidize and decompose the odor in the air flow, and fine particles of titanium oxide are irradiated with ultraviolet rays to generate active molecules. In the photocatalytic method that deodorizes by causing a chemical reaction with the odor in the air stream, the chemical reaction rate is slower than the adsorption rate, and therefore the deodorizing effect is not fast.

In order to use such a deodorizing filter for a long period of time, a means for desorbing adsorbed odorous molecules with an electric heater to regenerate it is disclosed in, for example, JP-A-63 / 1988.
-127759, JP-A-2-78418,
JP-A-3-233237 and JP-A-9-187.
No. 624 is disclosed. Further, means for photodecomposing adsorbed odorous molecules with a photocatalyst to regenerate is disclosed in, for example, JP-A-10-227469.

[0006]

In the conventional method of regenerating the deodorizing filter as described above with the electric heater, the adsorbed odorous molecules can be desorbed and regenerated with the electric heater, so that the deodorizing effect is fast-acting. It has the advantage that a high deodorizing filter can be used for a long period of time. However, in the conventional method of regenerating this deodorizing filter with an electric heater, it is necessary to install duct piping for discharging the odor removed from the deodorizing filter to the outside of the room, and fire countermeasures are taken because an electric heater is used. There was a problem in that it had to be done and the cost increased.

Further, in the conventional method in which the adsorbed odor molecules are photolyzed by a photocatalyst to be regenerated, an advantage is that a deodorizing filter having a high deodorizing effect can be used for a long period of time as in the above case. Have. However, in the conventional method of photodecomposing and regenerating with this photocatalyst, it is necessary to use an expensive and short-lived ultraviolet lamp, and since the deodorizing material is porous, it is difficult to irradiate the entire surface with ultraviolet rays, The problem was that it was difficult to reproduce.

Therefore, the present invention has been made to solve the above problems, and has a high deodorizing effect, a safe and inexpensive reusable deodorizing filter which can be reused for a long time, and It is an object to provide a method for regenerating a deodorizing filter.

[0009]

Means for Solving the Problems As a result of earnest studies, the present inventor has noticed that a high-performance hygroscopic material has a water film condensed on the surface of the hygroscopic material even at room temperature and low humidity. However, when the water-soluble odor gas, which is the main component of cigarette odor and residual cooking odor, comes into contact with the water film, it is dissolved and removed, and the water-soluble odor gas dissolved by washing the hygroscopic material together with the water film We focused on the fact that it can be washed away and regenerated.

The peculiar odor gas "ammonia" which dissolves instantaneously in the presence of a small amount of water, and the water-soluble "acetaldehyde" and "acetic acid" which are the main components of cigarette odor and residual cooking odor, When a hygroscopic material formed into a honeycomb shape is passed, it is dissolved and removed with high efficiency. And
It was found that when the hygroscopic material is washed with water, the dissolved water-soluble odorous gas is washed away and can be regenerated, and the present invention has been completed.

The regenerative deodorizing filter according to the present invention has a hygroscopic material and a condensed water film formed on the surface of the hygroscopic material.

In the above regenerative deodorizing filter, the hygroscopic material is made of hygroscopic ceramics.

In the above regenerative deodorizing filter, the hygroscopic material is hygroscopic fiber.

In the above regenerative deodorizing filter, the hygroscopic material is formed into a honeycomb shape.

The method for regenerating a deodorizing filter according to the present invention comprises the steps of forming a condensed water film on the surface of a hygroscopic material, and dissolving a water-soluble odor gas in the water film on the surface of the hygroscopic material, And a step of washing the dissolved water-soluble odorous gas together with the water film.

In the method for regenerating the above deodorizing filter,
The aqueous solution used for the washing with water is a weakly acidic aqueous solution.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (Example) Typical examples of indoor air pollution due to odorous gas include cigarette odor, toilet odor, pet odor, rotten odor, residual cooking odor, and the like. It is a composite, and the constituent gases that compose it differ depending on the type of odorous gas.

The main components of cigarette odor are acetaldehyde, ammonia and acetic acid, and the main components of toilet odor, pet odor and putrefaction odor are hydrogen sulfide, methyl mercaptan and ammonia. In addition, the main component of residual cooking odor is lower aldehyde,
It is a lower fatty acid. It can be seen that among the above component gases, acetaldehyde, ammonia, acetic acid, lower aldehydes, and lower fatty acids are water-soluble odor gases, and the main components of cigarette odors and residual cooking odors are water-soluble odor gases.

Hydrogen sulfide and methyl mercaptan are
Not a water-soluble odorous gas. It is known that among the above-mentioned water-soluble odor gases, ammonia is instantaneously dissolved in the presence of water, and even a small amount of water dissolves 3000 times or more of ammonia in a volume of water. Formaldehyde and acetaldehyde, which are lower aldehydes, are also water-soluble and dissolve in the presence of water. Further, lower fatty acids such as formic acid and acetic acid are also water-soluble, and dissolve in the presence of water.

FIG. 1 is a conceptual diagram showing the principle of the regenerative deodorizing filter according to the present invention. In FIG. 1, reference numeral 1 is a hygroscopic material, and 2 is a water film formed by moisture condensed on the surface of the hygroscopic material 1. Reference numeral 3 denotes a water-soluble odorous gas in the air, showing that the water-soluble odorous gas 3 is dissolved in the water film 2 formed on the surface of the hygroscopic material 1.

The hygroscopic material 1 shown in this figure is preferably made of hygroscopic ceramic or hygroscopic fiber which is a hygroscopic porous material so that the surface area thereof is enlarged in order to dissolve a large amount of water-soluble odorous gas 3. . Examples of the hygroscopic ceramics include materials based on silica gel or zeolite, and these materials are preferably used because of their high hygroscopicity.

Examples of zeolites include porous aluminum and calcium silicates. In the regenerative type deodorizing filter, if the hygroscopic material 1 is composed of hygroscopic ceramics, it has excellent water resistance and can remove and regenerate the odorous gas components dissolved by washing with water, thereby achieving a long service life. Is preferred and is preferable.

As the hygroscopic fibers, hygroscopic organic polymer fibers such as cellulose fibers and nylon fibers are used. In the regenerative deodorizing filter, hygroscopic material 1
If it is constituted by a hygroscopic fiber, the hygroscopic material 1
Is a hygroscopic fiber, it is a flexible deodorizing filter, which is preferable because it can be easily processed. In the regenerative deodorizing filter shown in FIG. 1, the hygroscopic material 1
And a condensed water film 2 formed on the surface of the hygroscopic material 1.

Therefore, deodorization is performed by passing the contaminated air containing water-soluble odor gas as a main component through the deodorizing filter and dissolving the water-soluble odor gas 3 in the water film 2 condensed on the surface of the hygroscopic material 1. It can be carried out. Moreover, since the deodorizing filter can be regenerated by washing the dissolved water-soluble odorous gas 3 together with the water film 2, the deodorizing filter can be reused for a long period of time and economically. It can also be advantageous from the standpoint of environmental protection.

Embodiment 1. FIG. 2 is a perspective view showing the structure of the regenerative deodorizing filter according to the first embodiment of the present invention. In FIG. 2, 4 is a hygroscopic material formed in a lattice shape. As the hygroscopic material 4, for example, hygroscopic ceramics is used. Examples of hygroscopic ceramics include silica gel and zeolite, which are suitable because of their high hygroscopicity.

In the present embodiment, silica gel is used as the hygroscopic material 4, and a honeycomb structure as shown in FIG. 2 is obtained through the usual ceramic manufacturing process. Specifically, a raw material was formed into a lattice shape using cordierite as a binder and fired in a firing furnace to obtain a regenerated deodorizing filter having a honeycomb structure. Although the regenerative deodorizing filter can be used as it is in FIG. 2, it can be reinforced by incorporating it in the filter frame.

In the present embodiment, since the hygroscopic material 4 is made of hygroscopic ceramics, it has excellent water resistance and can remove and regenerate odorous gas components dissolved by washing with water, thereby extending the life. Can be planned. In addition, since the hygroscopic material 4 is formed in a honeycomb shape, the air passage can be made to have a low pressure loss, and the deodorizing effect can be extremely fast.

The regenerative deodorizing filter need not be made of the above-mentioned material, as long as it can withstand impact and can be washed with water. For example, even if the surface of the filter is coated with a hygroscopic material, it can be adsorbed by the moisture adhering to the surface, and even if the finely crushed hygroscopic material is stuck to the surface, the surface area is Since it increases, the characteristics close to those of the porous material can be obtained.

Embodiment 2. FIG. 3 is a perspective view showing the structure of the regenerative deodorizing filter according to the second embodiment of the present invention. In FIG. 3, 5 is a hygroscopic material formed in a flat plate shape, and 6 is a hygroscopic material formed in a corrugated plate shape. For example, hygroscopic ceramics are used as the hygroscopic materials 5 and 6. Examples of hygroscopic ceramics include silica gel and zeolite, which are suitable because of their high hygroscopicity.

In the first embodiment, the case where silica gel is used as the hygroscopic material 4 has been described, but in the present embodiment, zeolite is used as the hygroscopic materials 5 and 6. Next, the mixed aqueous solution of this zeolite and pulp was wet-processed to prepare a zeolite-mixed paper.

Next, the zeolite-mixed paper is corrugated to form a flat hygroscopic material 5.
A honeycomb structure as shown in FIG. 3 in which the hygroscopic material 6 formed in the shape of a corrugated plate and the hygroscopic material 6 formed in a corrugated shape were alternately laminated in the vertical direction was obtained. Then, by incorporating this into a filter frame, a regenerative deodorizing filter was obtained.

In this embodiment, since the hygroscopic materials 5 and 6 are made of hygroscopic ceramics, they are excellent in water resistance and can remove and regenerate the odorous gas components dissolved by washing with water, and thus have a long life. Can be realized. Further, since the hygroscopic materials 5 and 6 are formed in a honeycomb shape, it is possible to reduce the pressure loss in the air passage and to enhance the deodorizing effect very quickly.

Embodiment 3. FIG. 4 is a perspective view showing the structure of the regenerative deodorizing filter according to the third embodiment of the present invention. In FIG. 4, 7 is a hygroscopic fiber, and 8 is a filter frame for housing the hygroscopic fiber 7. The hygroscopic fiber 7 is used as the hygroscopic material. Examples of the hygroscopic fibers 7 include hygroscopic organic polymer fibers such as cellulose fibers and nylon fibers.

These cellulose fibers and nylon fibers used as the hygroscopic fibers 7 are passed through a nonwoven fabric producing machine to produce a nonwoven fabric having air permeability. And
By sandwiching the hygroscopic fiber 7 of the nonwoven fabric in the filter frame 8 having a thickness of about 5 to 50 mm, a regenerative deodorizing filter as shown in FIG. 4 is obtained.

According to this regenerative type deodorizing filter, water vapor in the air can be adsorbed and condensed on the surface to form a water film to quickly dissolve and remove the water-soluble odorous gas. In addition, this regenerated deodorizing filter made of a non-woven fabric can be repeatedly used because the adsorbed water-soluble odorous gas can be easily washed off with water, and since it is a non-woven fabric, it can be easily processed according to the shape of the filter.

In this embodiment, since the hygroscopic material is composed of the hygroscopic fiber 7, since the hygroscopic material is the hygroscopic fiber 7, it becomes a flexible deodorizing filter and can be easily processed. .

Here, the results of evaluating the pressure loss of the filter and the removal efficiency of the water-soluble odorous gas using the regenerative deodorizing filters produced in the above-mentioned first to third embodiments will be described. Since the pressure loss of the filter depends on the wind speed in FIG.
It is a figure which shows the measurement result of the pressure loss of the reproduction | regeneration type deodorizing filter of 3.

As can be seen from FIG. 5, the higher the wind speed, the larger the pressure loss of each of the filters in the first to third embodiments. For the same wind speed, the pressure loss increases in the order of Embodiment 1 <Embodiment 2 <Embodiment 3, and conversely, Embodiment 3> Embodiment 2> Embodiment 1. It is getting smaller.

The pressure loss is preferably as small as possible, and may be zero. On the other hand, if the pressure loss becomes too large,
Therefore, a powerful fan must be used, which is not preferable for commercialization. From the results of FIG. 5, the pressure loss with respect to the wind speed can be reduced in the order of Embodiment 3> Embodiment 2> Embodiment 1, which is preferable.

The honeycomb structure filter in the first embodiment can minimize the pressure loss with respect to the wind speed, and the honeycomb structure filter in the second embodiment can reduce the pressure loss next. The fiber using the hygroscopic fiber of the third embodiment was inferior in pressure loss as compared with the first and second embodiments. In addition, from the results of FIG.
It was confirmed that each had a pressure loss within a range that could be used as a deodorizing filter.

Regarding the deodorizing performance, the ratio of the odorous gas removed when the air containing the odorous gas passes through the deodorizing filter once can be expressed by "transient removal efficiency". Here, the transient removal efficiency of ammonia, acetaldehyde, and acetic acid, which are typical water-soluble odorous gases, was measured. FIG. 6 shows the measurement results of the transient removal efficiency of the regenerative deodorizing filters of the first to third embodiments at the wind speeds of 0.2, 0.5 and 1.0 m / s because the transient removal efficiency depends on the wind speed. FIG.

From the measurement results of FIG. 6, the first to third embodiments are shown.
Confirmed that each of them had a high transient removal efficiency. As can be seen from the results of FIG. 6, in any of the three types of odorous gas and in any wind speed, the ratio of the odorous gas removed is in the relationship of the first embodiment> the second embodiment> the third embodiment. there were. From this, the filter of the first embodiment has the best odor gas removal efficiency, the filter of the second embodiment is next, and the filter of the third embodiment is next.

In order to dissolve a larger amount of odorous gas, a structure capable of forming a larger amount of water film on the surface of the hygroscopic material is preferable. Therefore, a structure having a larger surface area of the hygroscopic material is preferable. The result of the removal efficiency of the odorous gas in FIG. 6 depends on the surface area relationship of the hygroscopic material.

Next, a life test for ammonia, acetaldehyde and acetic acid was carried out using the regenerative deodorizing filters of the first to third embodiments, and when the initial transient removal efficiency was reduced to 60%, It was regenerated by washing with water. Acetaldehyde and acetic acid could be completely regenerated by soaking in tap water for 1 hour.

However, regarding ammonia, 8
It was not completely regenerated unless it was soaked for more than a time. Therefore, in order to regenerate ammonia in a short time, it was devised to use a weakly acidic aqueous solution, and when tap water containing 1 to 5% of commercially available citric acid as a food additive was used, it took 1 hour. I confirmed that it was completely reproduced.

The main components of cigarette odor are acetaldehyde, ammonia and acetic acid. As a result of being used as a regenerative deodorizing filter dedicated to cigarette odor, the cigarette odor is highly efficiently deodorized,
It was confirmed that there was a life span of 2 to 6 months. Further, at the end of the life, it was possible to completely regenerate it by immersing it in a weakly acidic aqueous solution for 1 hour.

The main components of the residual cooking odor are lower aldehydes and lower fatty acids, both of which are water-soluble odor gases. Then, as a result of using it as a regenerative deodorizing filter dedicated to the residual cooking odor, it was confirmed that the residual cooking odor was deodorized with relatively high efficiency and that it had a life of 1 to 3 months. Also,
At the end of its life, it could be completely regenerated by immersing it in tap water for 1 hour.

[0048]

EFFECTS OF THE INVENTION According to the present invention, a water-soluble odor gas is formed by constructing a regenerative deodorizing filter having a hygroscopic material and a condensed water film formed on the surface of the hygroscopic material. Deodorizing can be performed by passing the contaminated air containing as a main component through a deodorizing filter and dissolving the water-soluble odorous gas in the water film condensed on the surface of the hygroscopic material. In addition, since the deodorizing filter can be regenerated by washing the dissolved water-soluble odorous gas with the water film, it is possible to reuse the deodorizing filter for a long period of time, and economically protect the global environment. It can also be advantageous from the standpoint of.

In the above regenerative type deodorizing filter, the hygroscopic material is made of hygroscopic ceramics, so that the hygroscopic material is hygroscopic ceramics, so that the hygroscopic material is excellent in water resistance and the odorous gas component dissolved by washing with water is used. Can be removed and regenerated, and the life can be extended.

In the above regenerative deodorizing filter, the hygroscopic material is composed of hygroscopic fibers, so that the hygroscopic material is a hygroscopic fiber, so that it becomes a flexible deodorizing filter and facilitates processing. be able to.

In the above regenerative type deodorizing filter, by forming the hygroscopic material into a honeycomb shape, the hygroscopic material is formed into a honeycomb shape, so that the air passage can have a low pressure loss. At the same time, the rapid effect of the deodorizing effect can be made extremely high.

According to the present invention, a condensed water film is formed on the surface of the hygroscopic material, and a water-soluble odor gas is dissolved in the water film on the surface of the hygroscopic material, and then the dissolved water-soluble material is dissolved. By configuring the regeneration method of the deodorizing filter so as to include a step of washing the odorous gas together with the water film, the contaminated air having a water-soluble odorous gas as a main component is passed through the deodorizing filter, and the surface of the hygroscopic material is Deodorization can be performed by dissolving a water-soluble odorous gas in the condensed water film. In addition, since the deodorizing filter can be regenerated by washing the dissolved water-soluble odorous gas with the water film, it is possible to reuse the deodorizing filter for a long period of time, and economically protect the global environment. It can also be advantageous from the standpoint of.

In the above method of regenerating the deodorizing filter,
By configuring the aqueous solution used for washing with water to be a weakly acidic aqueous solution, the deodorizing performance for ammonia can be completely reproduced by using the weakly acidic aqueous solution when the regenerative deodorizing filter is regenerated.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing the principle of a regenerative deodorizing filter according to the present invention.

FIG. 2 is a perspective view showing the structure of the regenerative deodorizing filter according to the first embodiment of the present invention.

FIG. 3 is a perspective view showing a structure of a regenerative deodorizing filter according to a second embodiment of the present invention.

FIG. 4 is a perspective view showing a structure of a regenerative deodorizing filter according to a third embodiment of the present invention.

FIG. 5 is a diagram showing measurement results of pressure loss of the regenerative deodorizing filters of Embodiments 1 to 3 at a wind speed of 0.2 to 1.0 m / s.

FIG. 6 is a diagram showing the measurement results of the transient removal efficiency of the regenerative deodorizing filters of Embodiments 1 to 3 at wind speeds of 0.2, 0.5 and 1.0 m / s.

[Explanation of symbols] 1 hygroscopic material, 2 water film, 3 water-soluble odor gas, 4
Hygroscopic material formed in a lattice shape, 5 Hygroscopic material formed in a flat plate shape, 6 Hygroscopic material formed in a corrugated plate shape, 7
Hygroscopic fiber, 8 filter frames.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroyasu Kuwasawa             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. (72) Inventor Makoto Furukawa             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. (72) Inventor Naoko Yokoya             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. F-term (reference) 4C080 AA03 AA05 BB02 BB04 CC02                       CC04 CC05 CC08 CC12 CC13                       CC14 HH09 JJ03 JJ06 KK08                       LL08 LL10 MM01 MM14 MM15                       NN02 NN04 NN06 NN22 NN24                       NN28 QQ01 QQ03 QQ17                 4D020 AA09 BA23 BB01 BB07 BC10                       CB33 CC16

Claims (6)

[Claims] 1. A regenerative deodorizing filter comprising a hygroscopic material and a condensed water film formed on the surface of the hygroscopic material. 2. The regenerative deodorizing filter according to claim 1, wherein the hygroscopic material is hygroscopic ceramics. 3. The regenerative deodorizing filter according to claim 1, wherein the hygroscopic material is hygroscopic fiber. 4. The regenerative deodorizing filter according to claim 1, wherein the hygroscopic material is formed in a honeycomb shape. 5. A step of forming a condensed water film on the surface of the hygroscopic material, a step of dissolving a water-soluble odor gas in the water film on the surface of the hygroscopic material, and the dissolved water-soluble odor gas. And a step of rinsing the water film with the water film. 6. The method for regenerating a deodorizing filter according to claim 5, wherein the aqueous solution used for the water washing is a weakly acidic aqueous solution.