JP3933525B2 - Deodorization device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a deodorizing apparatus for deodorizing by decomposing odor components and harmful substances contained in the air.
[0002]
[Prior art]
In recent years, along with the steady environmental pollution such as outdoor air and noise, the demand for air quality improvement in the living space has increased along with the progress of airtightness of houses. Of the air quality, the need for reduction of metabolic odor in cigarette smoke odor and care environment for sick people, or removal of harmful gas components typified by VOC (volatile organic substances) generated from residential building materials has become particularly large. Yes.
[0003]
To meet these demands, conventionally, a deodorization method by adsorbing odor molecules represented by activated carbon, or a method of changing the odor quality by reacting a malodorous component with other drug components has been adopted.
[0004]
Among the prior arts, the amount of adsorption is limited for deodorization and removal of harmful gas components by an adsorbent, and replacement of the deodorization filter has become indispensable for long-term use. Further, the deodorizing filter has a problem of generating odor due to the adsorbed odor molecules being released again at the end of the lifetime even during the lifetime.
[0005]
On the other hand, the method of changing the odor quality by reacting the odor component with another drug component consumes the drug component, so it is necessary to replace the absorbed drug once every one to two months, which is complicated. In addition, since the release amount of the drug component into the environment is controlled at room temperature, the release amount of the drug component increases when the room temperature is high, and the release amount against the deodorizing effect and the life of the drug component There was a difficulty in the related control.
[0006]
In addition, in order to decompose and remove harmful gas components such as formaldehyde, a catalytic reaction with a high oxidation-reduction potential is required, but oxidative decomposition with ozone does not lead to complete decomposition, but stops at the intermediate decomposition product stage. Therefore, it has been difficult to completely detoxify.
[0007]
Moreover, it is possible to generate active oxygen by irradiating a photocatalyst represented by titanium oxide with ultraviolet rays, and to completely decompose harmful gas components with its strong oxidizing power. Is not preferable from the viewpoint of environmental load at the time of disposal.
[0008]
[Problems to be solved by the invention]
In order to solve these problems, ozone and ultraviolet rays are generated by high-pressure discharge, and the photocatalyst module activated by the ultraviolet rays is used to decompose odor components and harmful substances contained in the air. There has been proposed a deodorizing apparatus in which generated ozone is decomposed by an ozonolysis means.
[0009]
This deodorization device is very excellent in terms of control of deodorization performance, complete decomposition of harmful gases, and environmental load when the device is discarded. There is a problem that a discharge sound corresponding to is generated. Further, depending on the conditions of high-voltage discharge, there is a problem that noise is generated and affects television reception.
[0010]
About discharge noise, as described in Japanese Patent Application No. 2001-159477 by the applicant of the present invention, it is effective to make the discharge frequency outside the human audible range, but it is less than 50 pps audible range. At the discharge frequency, the amount of ultraviolet light and ozone obtained by the discharge decreases in proportion to the frequency, and there is a problem that the deodorizing performance is impaired.
[0011]
In addition, when discharging at a frequency higher than the audible range, there will be no problems with the discharge sound or deodorizing performance, but in some cases, ozone generated in proportion to the discharge frequency is generated more than necessary, and the ozone decomposition means When the discharge of 20 kpps or more, which is higher than the audible range, is caused, the life of the control circuit is increased and the amount of heat generated by the control circuit increases, and a separate cooling device is required.
[0012]
The present invention has been made to solve the above problems, and solves the problems of deodorization performance and discharge sound by discharging at a frequency higher than the human audible range, and reduces the amount of ozone generated to reduce the ozone generation means. An object of the present invention is to provide a deodorizing device that extends the life and eliminates the need for a cooling device for a control circuit.
[0013]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the deodorizing apparatus according to claim 1 includes high-pressure discharge means for generating ozone and ultraviolet light, and odor activated by the ultraviolet light generated by the high-pressure discharge means and contained in the air. Supplying high voltage to the high- pressure discharge means in a deodorizing device in which a photocatalyst module that decomposes components and harmful substances, etc., and an ozone decomposition means that decomposes ozone generated by the high-pressure discharge means are arranged in the air passage. The power supply circuit is installed in the air passage cross-sectional area of the blower passage so that the discharge frequency by the high-pressure discharge means is higher than the audible range and is discharged intermittently.
[0014]
With this configuration, it is possible to extend the life of the ozone decomposition means by reducing the amount of ozone generated without causing the problem of discharge noise, while suppressing the amount of heat generated in the circuit section and eliminating the need for a dedicated cooling device Cost can be reduced.
[0015]
According to a second aspect of the invention, the discharge frequency of the high-pressure discharge means and above 20Kpps, while operating as intermittently performed by turning on and off the discharge at predetermined time intervals, intermittently performing the discharge operation The on / off frequency is 50 Hz or less or 20 kHz or more, and even if the discharge frequency is outside the audible range, the problem of noise generation due to the intermittent operation frequency being within the audible range Can be eliminated.
[0016]
According to a third aspect of the invention, in response to the detection value of the odor sensor are characterized in that so as to change the intermittent operation control of the high-pressure discharge means, odor of ozone generation amount and the circuit when relatively small The calorific value can be reduced.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a deodorizing apparatus (1) according to the present invention, and a blower fan is provided in an air passage (3) formed by a duct member (2) such as a cold air duct of a refrigerator or an air duct in an air conditioner. (4) is disposed, a photocatalyst module (5) is provided on the windward side, and an ozone decomposition catalyst filter (10) is disposed between the photocatalyst module (5) and the blower fan (4).
[0018]
The photocatalyst module (5) is a photocatalyst filter (6) (7) fixed by applying a photocatalyst material typified by titanium oxide on the surface of a substrate made of a porous ceramic such as alumina or silica and drying or sintering. ) Are placed next to each other, and a discharge electrode (8) formed by etching a thin plate of stainless steel or the like into a mesh shape is erected between the photocatalytic filters, and the two photocatalytic filters (6) (7) The counter electrode (9) formed in the same manner as the discharge electrode (8) is arranged on the windward and leeward sides of the air passage (3).
[0019]
The photocatalyst filter in the photocatalyst module (5) does not necessarily have two adjacent ones, but odorous components and ethylene-floating bacteria are present in a deodorizing device provided in the cold passage from the refrigerator compartment to the vegetable compartment. In the case where the number is relatively small, the counter electrode (9) and the discharge electrode (8) may be provided before and after one photocatalytic filter.
[0020]
(11) is a power supply circuit, and a positive pulsed DC high voltage is applied between the discharge electrode (8) and each counter electrode (9) by a high voltage generating transformer (12).
[0021]
The mesh size of the discharge electrode (8) is larger than the mesh size of the counter electrode (9). With this configuration, the discharge electrode (8) and the counter electrode (9) function as a discharge means for generating ultraviolet rays, and discharge occurs between both electrodes to generate ultraviolet rays having a wavelength of 380 nm or less.
[0022]
Further, when the discharge electrode (8) and the counter electrode (9) are discharged, ozone is generated together with ultraviolet rays. Therefore, the photocatalyst module (5) has a function of completely decomposing harmful gas components by generation of active oxygen due to ultraviolet rays, The ozone decomposing catalyst filter (10) that absorbs ozone installed at a predetermined distance from the photocatalyst module (5) to the leeward side of the photocatalyst module (5) is mainly composed of manganese dioxide. It is formed from a honeycomb-shaped sintered body.
[0023]
When operating the deodorizing apparatus (1) of the said structure, it carries out as follows. That is, when the power supply circuit (11) is energized to drive the blower fan (4) and a voltage is applied between the discharge electrode (8) and the counter electrode (9), discharge occurs between the electrodes and ultraviolet rays are generated. .
[0024]
By irradiating the photocatalyst filters (6) and (7) with ultraviolet rays, the active oxygen generated by activating the photocatalyst flows down the air passage (3), and a strong oxidizing action of hydroxyl radicals (free radicals) Deodorization is achieved by decomposing bonds of odorous gas components and organic compounds adhering to the surfaces of the photocatalytic filters (6) and (7) and making them odorless or reducing odor.
[0025]
In addition, the cell membrane of the fungus is embrittled and antibacterial, and the growth of microorganisms on the surface of the photocatalytic filter (6) and (7) is suppressed by oxidative degradation, so that the deodorization device (1) and air passage (3) wall surface Dissolve and remove dirt.
[0026]
As a comparative example for one embodiment of the present invention based on the above configuration, in the above operation, the peak voltage is 4 kV between the discharge electrode (8) and the counter electrode (9), which is higher than the human audible range. A continuous operation was performed by applying a voltage of 20 kpps (kilopulses / second) as the discharge frequency.
[0027]
In this case, as understood from the graph of the relationship between the discharge frequency and the noise level with the peak voltage of 4 kV shown in FIG. 2, the discharge sound generated when the discharge frequency is 20 kpps is above the human audible range, Since it was in the range where it was not felt as a sound, the noise value as a device was 17.6 db, a low value close to dark noise (15.4 db), and there was no problem.
[0028]
However, the discharged ozone was 1.1 ppm, exceeding the working environment standard of 0.5 ppm, and the resistance surface temperature on the power supply circuit (11) for supplying a high voltage was as high as 150 ° C. Usually, when the resistance surface temperature exceeds 70 to 80 ° C., the circuit life is extremely shortened. In this comparative example, a cooling device is required to maintain the circuit life. A study based on the example was performed.
[0029]
Example 1
As deodorizing apparatus of one embodiment of the present invention, the same configuration as FIG. 1, between the discharge electrode (8) and the counter electrode (9), the peak voltage is 4 kV, with providing a voltage of 20Kpps, discharge ON off interval for a predetermined time interval, for example, the on-time of 0.01 seconds, so as to intermittently drive the oFF time as 0.09 seconds.
[0030]
Frequency of operation is off number of times per second when operating in the intermittent is by below or 20kHz or more outside the audible range 50 Hz, also the frequency during discharge be outside the range of the audible range, intermittent The problem of noise generation due to the fact that the frequency during typical driving is within the audible range is eliminated.
[0031]
As a result, the noise value was 17.6 db, which was the same value as in the comparative example, but did not change. However, the exhausted ozone was 0.09 ppm, a value significantly below the working environment standard, and the resistance surface on the high voltage circuit (11) The temperature was 38 ° C., which was a level that did not require cooling for the circuit life.
[0032]
(Example 2)
A power supply circuit (11) for supplying a high voltage was installed on the air passage (3) while having the same basic configuration as that of Example 1. The noise value at this time is 17.6 db, the discharged ozone is 0.09 ppm, which is the same as the value in Example 1, and the resistance surface temperature on the high voltage circuit (11) is 32 ° C., which is lower than that in Example 1. There was no problem level.
[0033]
Usually, it is necessary to provide a heat radiating device such as a cooling fan in the heat generating part such as a resistor on the high voltage circuit (11). However, during the operation of the deodorizing device according to this embodiment, the fan is rotated to the air path. Since the wind always generates and intermittently discharges, install a high-voltage circuit (11) in a part of the cross-sectional area of the air path (3) to generate heat when the circuit generates heat. The air is forcedly cooled synchronously, and the heat generating portion can be cooled and radiated without the need for a separate heat radiating device.
[0034]
(Example 3)
The power supply circuit (11) including the high voltage generation transformer (12) is a photocatalyst on the air passage (3) as shown in FIG. It installed in the position shown to B between the ventilation fan (4) on the downstream side of A and the ozone decomposition | disassembly catalyst filter (10) upstream of a module (5), and compared. At the same time, a 10-hour deodorization durability comparison test was performed using ammonia that generates a manure odor, and the appearance was investigated.
[0035]
The results are as shown in the table of FIG. 4. The resistance surface temperature on the high voltage transformer (12) was the same temperature at 55 ° C. at both the A and B positions, which was low and no problem, but the photocatalytic module (5 ), Which was installed at position A, which is upstream of), was affected by ammonia, and rusting was observed in the metal part of the transformer (5). On the other hand, the B position on the leeward side could be cooled by clean air subjected to the oxidative decomposition action by the photocatalyst, and the high voltage transformer (5) could be protected from contamination by odorous substances.
[0036]
Example 4
Although not shown, an odor sensor such as a hot-wire semiconductor sensor using tin oxide as a sensitive material that detects a change in resistance when a odor substance is touched is provided in the deodorizer, the discharge frequency is 20 kpps, and the discharge off time is 0. The circuit was configured to change the on time between 0.01 and 0.09 seconds in proportion to the signal from the odor sensor for .05 seconds. The noise level at this time is as low as 16.8 to 17.8 db, and the amount of ozone generated can be set to 0.13 to 0.23 ppm, which is 0.5 ppm or less of the working environment standard. It was.
[0037]
【The invention's effect】
As described above, according to the configuration of the present invention, the ozone generation means is reduced by causing the discharge frequency to be intermittently discharged above the human audible range, thereby reducing the amount of ozone generated without causing the problem of discharge noise. In addition to extending the service life, the amount of heat generated in the circuit portion can be suppressed, and a dedicated cooling device is not required, thereby reducing the cost.
[Brief description of the drawings]
FIG. 1 is a schematic longitudinal sectional view of a deodorizing apparatus in Embodiment 1 of the present invention.
FIG. 2 is a graph showing the relationship between noise and discharge frequency by the apparatus of FIG.
FIG. 3 is a longitudinal sectional view showing a deodorizing apparatus according to Embodiment 3 of the present invention.
4 is a table showing experimental results in Example 3. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Deodorizing device 2 ... Duct member 3 ... Air path 4 ... Blower fan 5 ... Photocatalyst module 6, 7 ... Photocatalyst filter 8 ... Discharge electrode 9 ... Counter electrode 10 ... Ozone decomposition catalyst filter
11 ... Power circuit 12 ... Transformer

Claims (3)

High-pressure discharge means for generating ozone and ultraviolet light, a photocatalyst module that is activated by ultraviolet light generated by the high-pressure discharge means and decomposes odorous components and harmful substances contained in the air, and the high-pressure discharge means In the deodorizing device in which the ozone decomposing means for decomposing ozone generated by the air is disposed in the air passage, a power supply circuit for supplying a high voltage to the high- pressure discharge means is installed in the air passage cross-sectional area of the air passage. A deodorizing apparatus characterized in that the discharge frequency by the discharging means is set to be higher than the audible range and is discharged intermittently. The discharge frequency of the high-pressure discharge means is set to 20 kpps or more, and the discharge is operated to be intermittently performed by turning on / off at predetermined time intervals, and the on / off frequency of the operation to intermittently perform the discharge is 50 Hz or less. Or it is 20 kHz or more, The deodorizing apparatus of Claim 1 characterized by the above-mentioned. In response to the detection value of the odor sensor deodorizing apparatus according to claim 1, wherein it has to change the intermittent operation control of the high-pressure discharge means.

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