JP2004321841A - Dust removing/deodorizing apparatus and dust removing/deodorizing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dust removing/deodorizing apparatus capable of performing the treatment of a gas to be treated along with the dust removal/deodorization of the gas to be treated with high treatment efficiency even if a malodorous gas and dust are contained in the gas to be treated while having a merit using photocatalytic action, and a dust removing/deodorizing method using the same. <P>SOLUTION: The dust removing/deodorizing apparatus is equipped with an inflow port 1 for permitting the inflow of the gas to be treated, a filter F for removing dust from the inflow gas to be treated, photocatalyst bodies 4 capable of deodorizing the gas to be treated, light sources 5 for exciting the photocatalyst bodies 4 and a discharge means for discharging the gas treated by the excited photocatalyst bodies 4. The filter F and the photocatalyst bodies 4 are constituted as one set and the light sources 5 are arranged so as to be capable of irradiating the photocatalyst bodies 4 to perform the dust removal and deodorization of the gas to be treated. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a dust removing and deodorizing apparatus and a dust removing and deodorizing method, and more specifically, an inflow port through which a gas to be treated is introduced, a filter that removes the introduced gas to be treated, a photocatalyst capable of deodorizing the gas to be treated, The present invention relates to a dust removing and deodorizing apparatus including a light source for exciting a photocatalyst and a discharging unit for discharging gas processed by the excited photocatalyst, and a dust removing and deodorizing method using the same.
[0002]
[Prior art]
Although low-concentration odors from sewage caused by organic compounds contained in sewage, odor gas generated from various factories such as food factories, odor components generated from medical facilities such as hospitals, public facilities, etc. Since there are many generated places and the generated amount is not small, it is necessary to efficiently and quickly treat these odor components, and various methods for that purpose have been proposed and implemented.
[0003]
For example, a method for adsorbing and removing odor components using an adsorbent such as activated carbon, a catalyst treatment method for passing through a high-temperature catalyst to decompose, a plasma treatment method for decomposing odor components with plasma, Combustion treatment method of heating and burning to decompose, chemical treatment method of treating with chemicals using acid cleaning solution or alkali cleaning solution, photocatalyst treatment method of decomposing treatment using photocatalyst such as titanium oxide, deodorization using ozone Ozone treatment method and biological treatment method using microorganisms.
[0004]
Among them, the photocatalyst treatment method does not require frequent post-treatment after adsorption as in the adsorption removal method, does not need to be heated to a high temperature as in the catalyst treatment method, and is not affected by moisture as in the plasma treatment method. There is no need to provide a dehumidifying heater to reduce the amount, and it is not necessary to provide a large exhaust gas device as in the combustion treatment method, and it is not necessary to perform neutralization treatment as in the chemical treatment method, and it is large as in the ozone treatment method. It has advantages that it does not require a simple device, does not require the treatment of leaked ozone, and has a low processing speed unlike biological treatment.
[0005]
For example, a plurality of compartments connected to the flue gas exhaust passage of the incinerator and alternately communicating on the top lid side and the bottom plate side or the side wall side are provided at substantially equal intervals, and the compartments are filled with the photocatalyst, There has been proposed an invention of an exhaust gas treatment facility including a casing provided with an ultraviolet-transmissive quartz glass cylinder or the like in which an ultraviolet radiation lamp is mounted (for example, Patent Document 1).
[0006]
[Patent Document 1]
JP 2001-170453 A [Problems to be Solved by the Invention]
However, the exhaust gas treatment equipment of the above-described conventional technology is configured such that the exhaust gas discharged from the incinerator is filled with a photocatalyst and sequentially flows through a plurality of intricate compartments. The throughput is limited and the processing efficiency is never high. In addition, the gas to be treated generally contains dust such as dust, but is treated as it is in the conventional apparatus, and especially when the gas to be treated is large in dust, the function of the photocatalyst is early. In addition to the above, there is a problem that not only does the processing efficiency not increase, but also that a large amount of cost is required for maintenance work. In addition, there is a problem that if the processing is performed separately, the entire equipment becomes large.
[0007]
Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art, while having the advantage of utilizing the photocatalysis, and in the case where the gas to be treated contains dust in addition to odor components. Even if there is, it is an object of the present invention to provide a dust removing and deodorizing apparatus and a dust removing and deodorizing method capable of simultaneously removing dust and deodorizing gas to be treated with high treatment efficiency.
[0008]
[Means for Solving the Problems]
The above object is achieved by the invention described in each claim. That is, the characteristic configuration of the dust removing and deodorizing apparatus according to the present invention includes an inlet for introducing the gas to be treated, a filter for removing the introduced gas to be treated, a photocatalyst capable of deodorizing the gas to be treated, and this photocatalyst. A light source that excites the body, and a discharge unit that discharges the gas processed by the excited photocatalyst, wherein the filter and the photocatalyst are configured as a set, and the light source is the photocatalyst. Is disposed so as to be able to irradiate the gas to be treated, and the gas to be treated can be subjected to dust removal and deodorization treatment.
[0009]
According to this configuration, the dust removal and the deodorization treatment of the gas to be treated can be performed substantially at the same time, the dust is less likely to adhere to the inner wall of the apparatus, maintenance is facilitated, and the gas to be treated can be treated with high treatment efficiency. In addition, the processing cost can be reduced, and the entire apparatus configuration can be made compact, so that the equipment cost can be reduced and the space can be saved.
[0010]
As a result, while having the advantage of utilizing the photocatalysis, even when the gas to be treated contains an odor component and dust, the removal and deodorization of the gas to be treated can be performed with high treatment efficiency. It was possible to provide a deodorizing and deodorizing device that can be processed together.
[0011]
It is preferable that the filter is formed in a convex or concave shape so as to face the gas to be treated to be flowed in, and the photocatalyst is preferably carried on a downstream surface of the filter.
[0012]
According to this configuration, the passage cross section of the gas to be treated can be increased, so that the time for the gas to be treated to pass through the photocatalyst can be lengthened (passing speed can be reduced), and the odor component in the gas to be treated and the photocatalyst can be reduced. The contact time with the body can be extended, dust can be removed and deodorized at the same time with high efficiency even in a small space, and the dust in the gas to be treated is removed before it is deodorized by the photocatalyst. Deodorizing performance of the body can be maintained for a long time.
[0013]
It is preferable that the light source is disposed downstream of the filter formed in a convex or concave shape.
[0014]
According to this configuration, the light source surface is less likely to be contaminated, the irradiation efficiency can be kept high, the maintenance work can be reduced, and the processing cost can be reduced.
[0015]
The filter may be formed in a convex or concave shape so as to face the gas to be processed, and the photocatalyst may be supported on an upstream surface of the filter.
[0016]
According to this configuration, when the amount of dust in the gas to be treated is relatively small, it is easy to employ a powerful pulse jet method or a reverse jet method for cleaning the filter, which facilitates maintenance and reduces processing costs.
[0017]
Further, a characteristic configuration of the dust removing and deodorizing method according to the present invention resides in that a gas to be treated is treated using the dust removing and deodorizing apparatus according to any one of claims 1 to 4.
[0018]
According to this configuration, while having the advantage of utilizing the photocatalytic action, even when the odor component and dust are contained in the gas to be treated, it is possible to remove the dust from the gas to be treated with high treatment efficiency. It is possible to provide a dust removal and deodorization method capable of treating both deodorization and deodorization.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an example of a schematic sectional structure of a dust removing and deodorizing apparatus according to the present embodiment. This deodorizing apparatus includes an inlet 1 through which a gas to be processed flows, an exhaust fan (not shown) for forcibly exhausting the processed gas from above, and an exhausting unit including an exhaust port 2, and a dust removing device. And a casing A having a dust discharge port 3 for discharging. In the casing A, the gas to be treated is carried on the inner surface side (downstream side) of a filter cloth F, which is a kind of filter for removing the dust in the gas to be treated by flowing the gas to be treated, and the inflowing gas to be treated is deodorized. It has a photocatalyst 4 that can be processed and a light source 5 that excites the photocatalyst 4 downstream of the photocatalyst 4.
[0020]
The filter cloth F is composed of a large number of convex bag filters having a substantially U-shaped cross section so as to face the gas to be treated to be flowed in, and the photocatalyst 4 is provided on the inner surface of each convex filter cloth F. It is carried and both are integrally formed as one set. The downstream ends of the convex filter cloths F are connected by the partition walls 6, and are arranged so as to cross the cross section of the casing A. As described above, since the cross-sectional area of the gas to be treated is increased in the filter cloth F, the time for the gas to be treated to pass through the photocatalyst 4 can be increased (the passing speed can be reduced), and the gas to be treated can be reduced. The contact time between the odor component in the inside and the photocatalyst can be lengthened, and the deodorizing treatment efficiency increases.
[0021]
The filter F may be made of a metal fiber filter, a metal sintered filter, a metal mesh filter, a ceramic filter, or the like, in addition to a filter cloth made of glass fiber, synthetic fiber such as PPS, PTFE, or nylon. It is formed so that dust in the gas to be treated hardly adheres to the body 4. However, the photocatalyst 4 is not necessarily required to be integrally supported by the filter F, and the filter F covers the whole or a part of the outer peripheral side of the photocatalyst 4 so as to form a set. It may be configured.
[0022]
That is, the photocatalyst 4 may be filled in a porous cylindrical transparent case, the outer peripheral surface of the case may be covered with a filter cloth, and the light source may be arranged inside the case. The photocatalyst 4 may be composed of only a photocatalyst granulated to an appropriate size, or a photocatalyst supported on various carriers such as porous metal, activated carbon, activated alumina, silica gel, and porous ceramics. There may be. The granulation of the photocatalyst can employ a generally known granulation method such as a tumbling granulation method, and is not particularly limited. As the shape of the carrier, various shapes such as a granular shape, a spherical shape, and an indefinite shape can be adopted, and the size can be adopted from several tens μm to several mm in diameter.
[0023]
The photocatalyst may be a compound other than titanium dioxide as long as it has a property of generating conduction electrons and holes by irradiation with excitation light, or activated carbon, graphite, silica, and titanium dioxide as main components. An adsorbent such as alumina or an element that promotes the oxidizing action such as platinum, palladium, ruthenium, or silver may be added. Titanium dioxide is preferably of the anatase type, but may be of the rutile type or other crystalline forms.
[0024]
Dust adhering to the filter F can be removed by a vibration method, a back pressure method, a reverse jet method, a pulse jet method, or the like.
[0025]
A light source 5 such as an ultraviolet lamp is arranged inside each of the cylindrical photocatalysts 4 supported by the filter cloth. That is, the light source 5 is disposed inside the photocatalyst and on the downstream side through which the gas to be treated flows, and is effectively excited by ultraviolet rays (preferably at a wavelength of 300 to 345 nm) emitted from the light source 5 to perform photocatalysis. The gas to be treated is deodorized while being in contact with the photocatalyst exhibiting the following. As described above, since the light source 5 is disposed on the downstream side of the photocatalyst 4, the surface thereof is not easily contaminated, and the irradiation efficiency can be maintained high. However, since the photocatalyst itself such as titanium dioxide is water-resistant and can be easily washed by washing with water, high treatment efficiency can be maintained by washing with water regularly or irregularly.
[0026]
As the light source 5, an ultraviolet lamp is generally used, and a black light, a fluorescent lamp, a germicidal lamp, an ultraviolet LED, or the like can be used, but is not limited thereto. The irradiation intensity of the light source 5 on the photocatalyst surface is preferably about 1 to 10 mW / cm ² .
[0027]
Examples of the odor components in the gas to be processed by the deodorizing apparatus of the above embodiment include aldehydes, carboxylic acids, hydrogen sulfides, mercaptans, amines, ammonia and the like, and other organic halogens such as dioxins and benzopyrene. It can be treated even if it contains a compound, a volatile organic compound (VOC), and PCB. In addition, it is preferable that oxygen or moisture is contained in the gas to be treated, because the activation of the photocatalyst can be enhanced, and these may be introduced into the flow path of the gas to be treated.
[0028]
【Example】
(Example)
Titanium dioxide particles were applied and supported on the inner peripheral surface of a commercially available bag filter (made of a filter cloth made of PPS (polyphenylene sulfide)) to obtain the structure shown in FIG. A gas to be treated containing 5 ppm of acetaldehyde, which is an odor component, was passed through this device at a flow rate of 10 m ³ / h. The inside size of the casing of the device is about 200 (width) × about 180 (depth) × about 200 (height), and the height (length in the flowing direction) of the filter cloth supporting the photocatalyst is 180 mm. . As the light source, ten 100 W black lights were used. The irradiation intensity on the filter cloth surface was 1 to 5 mW / cm ² . The concentration of the odor component on the outlet side was measured with a detector tube, and the pressure loss (initial) of the device was measured. The pressure loss was determined by measuring the differential pressure between the inlet and the outlet of the device using a micro differential pressure gauge. As a result, the concentration of acetaldehyde on the outlet side was less than 1 ppm, and the pressure loss was 50 mmAq.
[0029]
[Another embodiment]
(1) The dust removing and deodorizing device may be configured as shown in FIG. That is, in this dust removing and deodorizing device, the gas to be treated flows in from above the casing A ', and a plurality of cylindrical filters F' are arranged so as to extend between the side walls inside the casing A '. The photocatalyst 4 is carried on the inner peripheral surface of the photocatalyst. A light source 5 such as an ultraviolet lamp is inserted on the inner peripheral surface side of the photocatalyst 4. The gas to be treated which has flowed in from the upper inlet 1 flows through the inside of the cylindrical filter F ', and is then discharged from the outlet 2 provided on the other end side. Even with such a configuration, the same effect as that of the apparatus of FIG. 1 can be exerted. The dust adhering to the filter F 'is appropriately blown off, dropped from the lower dust outlet 3 and discharged.
[0030]
(2) When there is little dust in the gas to be treated, the gas may be configured as shown in FIG. That is, the light source 5 is arranged on the upstream side of the photocatalyst 4, and the filter F for removing dust in the gas to be treated is arranged on the downstream side of the photocatalyst 4. In this way, when the filter F is cleaned by the pulse jet method using the compressed air, the impact applied to the light source 5 can be reduced and the light source 5 can be protected from being damaged. Also in the case of cleaning by a method, dust can be easily removed from the filter cloth constituting the filter F without any trouble, which is convenient. Needless to say, in performing the pulse jet method and the reverse jet method, it is not necessary to use a multi-chamber structure, so that the overall configuration can be made compact, the ventilation speed can be increased, and the cleaning efficiency can be increased.
[0031]
(3) When there is little dust in the gas to be treated, the light source 5 is disposed at both the upstream and downstream positions of the set of filters F and the photocatalyst 4 shown in FIGS. May be increased. In that case, it is preferable to dispose the photocatalyst 4 on both the inner and outer peripheral surfaces of the filter F.
[0032]
(4) The temperature of the gas to be treated is preferably room temperature. However, when a high-temperature gas such as exhaust gas from an incinerator is treated, an air-cooling fan for cooling the light source 5 or water cooling is used. The service life can be extended.
[0033]
(5) In the embodiment shown in FIGS. 1 and 3, the filter F and the photocatalyst 4 are formed so as to be convex in the flow direction of the gas to be treated. F and the photocatalyst 4 may be formed in a concave shape. In this case, the arrangement relationship between the filter F and the photocatalyst body 4 is arranged at a position opposite to the flow direction of the gas to be treated.
[0034]
(6) The gas to be treated is not particularly limited as long as it is a gas containing an odorous component, but is not particularly limited, but may be a multi-person gas such as a sewage treatment facility, a sewage flow passage, a food factory, various public facilities and a theater. It is highly effective when used in places where relatively large concentrations of gas to be treated are generated, although the concentration is relatively low, such as a facility where wastewater gathers.
[Brief description of the drawings]
FIG. 1 is a schematic sectional configuration diagram showing an example of a dust removing and deodorizing device according to the present invention. FIG. 2 is a schematic sectional configuration diagram showing another embodiment of a dust removing and deodorizing device according to the present invention. Schematic sectional configuration diagram showing still another embodiment of the apparatus.
1 inflow 2 discharge outlet (discharge means)
4 Photocatalyst 5 Light source F, F 'filter

Claims (5)

An inlet for introducing the gas to be treated, a filter for removing the introduced gas to be treated, a photocatalyst capable of deodorizing the gas to be treated, a light source for exciting the photocatalyst, and treatment with the excited photocatalyst A filter and a photocatalyst, wherein the filter and the photocatalyst are configured as one set, and the light source is arranged so as to be able to irradiate the photocatalyst, and A dust removing and deodorizing apparatus which enables a dust removal and a deodorization treatment for a processing gas. 2. The deodorizing and deodorizing apparatus according to claim 1, wherein the filter is formed in a convex or concave shape so as to face the gas to be processed, and the photocatalyst is supported on a downstream surface of the filter. 3. The deodorizing and deodorizing device according to claim 1 or 2, wherein the light source is disposed downstream of the convex or concave filter. 2. The deodorizing and deodorizing apparatus according to claim 1, wherein the filter is formed in a convex or concave shape so as to face the gas to be processed, and the photocatalyst is supported on an upstream surface of the filter. 3. A dust removing and deodorizing method for treating a gas to be treated using the dust removing and deodorizing apparatus according to any one of claims 1 to 4.

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