JPH0613084B2 - Deodorizer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a deodorizing device.

More specifically, when the air to be treated containing a malodorous component is contacted with the oxide solid catalyst by using the oxide solid catalyst, the deodorizing conditions are optimized when deoxidizing by oxidative decomposition to optimize the catalyst life. Deodorizing device for measuring the extension of

[Prior art]

In recent years, odor pollution has been widely taken up as a social problem,
Along with this, the necessity of treating and deodorizing air containing malodorous components has increased. From such knowledge, conventional catalytic oxidizers using catalysts, gas cleaning devices, ozone oxidizers, devices using adsorbents, devices using chemical deodorants, devices using masking agents, gas combustion devices A large number of deodorizing devices using these devices alone or in combination of two or more have been proposed, and are widely used industrially. However, there are merits and demerits, and industrially, there are many problems such as running cost and maintenance of equipment, and they are not sufficiently satisfactory.

Among the above devices, in the catalytic oxidation device using a catalyst, the main body of the deodorizing device is simple, and since a catalyst is used, there is generally no need for post-treatment or regeneration, but it is a preferable device, but it is still satisfactory. Not something you can do.

For example, a deodorizing effect of only a specific limited malodorous substance can be seen, or a pretreatment device such as removal of moisture in the air to be treated containing a malodorous component is required, or at least 200 at the time of contact reaction with a catalyst. There is a problem in selecting the optimum catalyst, such as the need for a reaction temperature of ℃ or more, and the life of the catalyst to be used, and it is not limited to these malodorous components.
It is desired to search for a device using a catalyst that can be used sufficiently.

Further, in the gas cleaning device, the ability to remove low-concentration malodorous components is insufficient, and since it is necessary to use a chemical, a cleaning waste liquid treatment device is required, which is not preferable.

Furthermore, although the ozone oxidizer is focused on the strong oxidizing power of ozone, it decomposes into harmless oxygen and is widely used in various fields such as deodorization, sterilization, bleaching and wastewater treatment. ing. However, some of the ozone used for the above-mentioned purposes is released into the atmosphere in an unreacted state, which may cause secondary pollution such as photochemical smog. Therefore, there is a problem that the adjustment of the amount of ozone added cannot sufficiently cope with the change in the malodorous component. Further, an ozone generator is required, the deodorizer is complicated and large, and the deodorizer and running costs are high, which is economically disadvantageous.

In addition, an apparatus using an adsorbent and an apparatus using a chemical deodorant have low ability to remove low-concentration malodorous substances, and there is a problem when regenerating the adsorbent or deodorant.

Further, a deodorizing device using a masking agent is not suitable from the viewpoint of deodorization and cannot be applied to a wide range.

Deodorization using a gas combustion device is economically disadvantageous because it requires a combustion device and running costs.

Further, regarding the above-mentioned single or a combination of two or more kinds, the apparatus becomes complicated, and it is economically unfavorable in terms of initial investment and running cost. For example, for those that are widely researched or developed industrially,
Although there is a catalytic oxidation device using ozone oxidation and a catalyst, the process is complicated and not economical, and further improvement is desired.

[Problems to be Solved by the Invention]

The present invention, when deodorizing the air to be treated containing a malodorous component, catalytically decomposes the malodorous substance at a comparatively low temperature without pretreating the air to be treated, and industrially simplifies the oxidation decomposition efficiency. And to provide a deodorizing device for malodorous components, which has a low initial investment and a low running cost.

[Means for Solving the Problems]

The present inventors have conducted intensive studies in view of such problems, and as a result, have completed the present invention.

The present invention has found a deodorizing device using an improved catalyst as a method that is industrially simplified and economically advantageous. The present invention provides a deodorizing device that easily and efficiently obtains a deodorizing effect without performing a pretreatment of the treated air during oxidative decomposition.

That is, the present invention, in a deodorizing device for oxidizing and decomposing a malodorous component in the air using a catalyst, a measuring device for detecting the concentration of the malodorous component in the air to be treated, and the concentration detected by the measuring device,
It has a clean air adjusting valve that introduces clean air from the introduction device when it exceeds a predetermined concentration and adjusts it to a predetermined concentration or less, and a heat exchanger that adjusts to a predetermined concentration and then brings it to a predetermined temperature. The present invention relates to a deodorizing device for aeration, oxidative decomposition, and aeration in a reaction tower filled with a catalyst.

[Detailed Disclosure of the Invention]

 Further, the present invention will be described in detail.

The catalyst used in the device of the present invention, MnO ₂ and CuO,
A composite oxide solid catalyst as an active ingredient is suitable.

More specifically, MnO ₂ and CuO, which are the main raw materials of the catalyst, are not particularly required to have high purity, and ordinary commercial products are used.

In order to mix these MnO ₂ and CuO, MnO ₂ and CuO are respectively finely divided by a pulverizer and then pulverized to 100 mesh or less to obtain MnO ₂ and CuO, and the pulverized products MnO ₂ and CuO are obtained.
After mixing with a binder, and further kneading with a kneader or the like by adding an appropriate amount of water, the mixture is dried at a temperature of about 105 to 120 ° C., allowed to cool and then pulverized into a predetermined shape, A suitable catalyst for use in the present invention is obtained.

In particular, the main composition as a suitable MnO ₂ and CuO-based mixed oxide solid catalyst that can be used in the present invention is preferably in the range of MnO ₂ ; 70 to 90% by weight, CuO; 30 to 10% by weight, and Preferably, MnO ₂ ; 77.5 to 82.5% by weight, CuO; 22.5 to 17.5% by weight are suitable.

The active ingredient contained in these is appropriate in the range of 80 to 98% by weight of the whole catalyst in the form of manganese-copper composite oxide, and other ingredients contained are alumina, silica, bentonite, zirconia, magnesia, titania. , Graphite, or any other material that does not adversely affect the active components of the catalyst composed of MnO ₂ and CuO, which are the main compositions described above.

Further, as the specific surface area of a suitable catalyst in the present invention,
The most common measurement method in the specific surface area measurement, i.e. the BET method, is preferably at least 150 to 400 m ² / g approximately, and more preferably, 200 to 300 m ² / g are preferred.

The shape of the catalyst that can be used in the present invention is not particularly limited and may be any of granular, spherical, pellet, tablet, honeycomb and the like.

As such a catalyst, generally widely used catalysts can be sufficiently used as long as they are within the scope of the present invention. According to a study by the present inventors, for example, Toyo CCI Co., Ltd. A catalyst such as one commercially available from CCI (abbreviated as CCI) (trade name K-01) can be used, and the catalyst within the above range is not particularly limited as a catalyst for the deodorizing device in the present invention. Not something.

The reaction conditions for deodorizing the air to be treated containing the malodorous component using the catalyst are to directly or indirectly heat or cool the air to be treated containing the malodorous component. The temperature for heating or cooling is preferably 100 to 200 ° C., more preferably 105.
A temperature of ~ 150 ° C is preferred. If it is less than 100 ° C, the reaction is insufficient, the activity of the catalyst is not sufficiently exhibited, and the malodorous component is not oxidatively decomposed, which is not preferable. On the other hand, if the temperature exceeds 200 ° C, the material of the deodorizer is deteriorated and the life of the catalyst is affected, which is not preferable.

The use of the deodorizing device in the present invention is not particularly limited, but the air containing odor emitted from general chemical plants, wastewater treatment plants, night soil treatment plants, printing plants, refuse incinerators, food plants, feed plants, etc. Can be used for processing.

The malodorous substance referred to in the present invention is not particularly limited, but includes air containing malodorous components discharged from the above-mentioned treatment plants and other various factories. For example, hydrogen sulfide, methyl sulfide, methyl mercaptan, ethylamine,
Methylamine, trimethylamine, dimethylamine, methyl disulfide, diethylamine, triethylamine, isobutylamine, acetone, pyridine, methylethylketone, acetaldehyde, benzene, xylene, toluene, phenol, acrolein, acetylene, acetic acid, butyric acid, etc. and others, chain organic Examples thereof include compounds, cyclic organic compounds, and the like, and all of these substances can be easily deodorized by using the deodorizing apparatus of the present invention and the catalyst suitable for the present invention.

According to the present inventors, the catalytic oxidation method using a normal catalyst is known to be easily affected by moisture in the air to be treated, but as long as a suitable catalyst in the present invention is used, It has been confirmed that it is hardly affected,
It has been confirmed that there is no effect on the catalyst if the relative humidity is 200% or less, preferably 150% or less.

The space velocity (SV) in the present invention varies depending on the concentration and composition of the malodorous component contained in the air to be treated,
It is preferably about 200,000 hr-1.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a flow sheet showing a preferred embodiment of the present invention.

The air to be treated 1 containing a malodorous component is blown to the heat exchanger 7 by the exhaust fan 2. Before being blown to the heat exchanger 7, the malodorous component in the air 1 to be treated is measured by the malodorous component measuring device 5, and is controlled by the clean air regulating valve 4 so as to have a predetermined concentration via the controller 6.

If the concentration exceeds a predetermined set value, the controller 6 detects it with the measuring device 5 so that the malodorous component becomes equal to or lower than the predetermined concentration.
The opening of the clean air adjusting valve 4 is adjusted, the clean air 3 is sucked, and the air 1 to be treated is diluted to a predetermined concentration or less.

The control conditions may be appropriately selected depending on the substance, composition, amount, concentration, etc. of the malodorous component of the air to be treated 1 depending on the concentration of the air to be treated.

Further, for the malodorous component measuring device 5, an odor sensor which is generally widely used in recent years is suitable. That is, a metal heat ray for detecting the odor concentration by a change in thermal conductivity due to gas adsorption on the surface of a metal oxide semiconductor (for example, SnO ₂ is generally used) and a change in electrical conductivity. Shaped semiconductor gas sensors are preferably used.

In this way, the air to be treated 1 containing the malodorous component in which the concentration of the malodorous component in the air to be treated is controlled to be equal to or less than the predetermined set value
Is then guided to the heat exchanger 7 and brought to a predetermined temperature by heating or cooling if necessary. The temperature is confirmed with a thermometer 8. The air to be treated 1 containing a malodorous component which has reached a predetermined temperature by heating or cooling is filled with a catalyst 9,
It is introduced into the reaction tower 10 and catalytically oxidized to remove the malodorous components, and is discharged as treated air 11.

The control conditions of the reaction tower 10 may be appropriately selected in consideration of the concentration of the air 1 to be treated containing a malodorous component, the treatment amount, the concentration of the malodorous component in the air to be treated, and the like, and the predetermined temperature condition and space. By controlling the speed, the offensive odor component can be removed.

Furthermore, in order to efficiently remove the deodorizing effect in order to enhance the deodorizing effect, washing the air to be treated containing the malodorous component with water, or washing with an acid or alkali is also preferable.

〔Example〕

 Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples.

Example 1 The air to be treated 1 containing methyl mercaptan, which is a typical malodorous component, was adjusted by sucking clean air 3 so that the concentration of methyl mercaptan was 1 ppm. The air to be treated after the adjustment is air having a relative humidity of 105% (temperature of 28 ° C.) and a blowing rate of 30 m ³ /
It was min.

The air to be treated after the above adjustment was subjected to a deodorizing test according to the flow sheet of FIG.

The test conditions were such that the outlet temperature 8 of the heat exchanger was adjusted to 105 ° C., and the amount of the oxidation catalyst packed in the reaction tower 10 was 100.

Under such conditions, we conducted a continuous deodorization test for 1000 hours,
When the concentration of methyl mercaptan in the treated air was measured every 200 hours, the results shown in Table 1 were obtained.

The deodorization rate was calculated by the following formula.

Deodorization rate (%) = (1-catalyst oxidizer outlet concentration / catalyst oxidizer inlet concentration) × 100 Further, as the composition of the catalyst used, those shown in Table 2 were used.

Comparative Example 1 A deodorization test was performed under the same conditions as in Example 1 except that the outlet temperature of the heat exchanger was set to 75 ° C.

When the deodorization rate was measured, the results shown in Table 3 were obtained.

As is clear from Table 3, the deodorization rate is clearly lower than that in Example 1.

Example 2 A deodorization test for a malodor generated from a wastewater treatment apparatus was conducted under the same apparatus and conditions as in Example 1. As a main component of the malodor, when analyzed by gas chromatography-mass spectrometry (GC-MS method), it was found to be a linear hydrocarbon and an organic compound system of a cyclic hydrocarbon column. In addition, when the odor concentration was measured based on the three-point comparative odor bag method described in the 1976 sensory test method survey report (Environment Agency), the catalytic oxidizer inlet and the catalytic oxidizer outlet were analyzed. The odor concentration of was as shown in Table 4.

The deodorization rate was calculated by the following formula.

Deodorization rate (%) = (1-catalyst oxidizer outlet concentration / catalyst oxidizer inlet concentration) × 100 [Effect of the Invention] The deodorizer of the present invention is an industrially simplified and economically advantageous device. Another object of the present invention is to provide a method for easily obtaining an effective deodorizing effect when catalytically oxidatively decomposing air containing a malodorous component using a deodorizing catalyst, without particularly performing pretreatment of the air. Further, by providing temperature control, air velocity and malodorous component concentration in the air to be treated, it is possible to provide a deodorizing device that continuously and economically treats air containing malodorous components. Therefore, the impact on the industry and the global environment is extremely large.

[Brief description of drawings]

FIG. 1 shows an example of a flow sheet of equipment suitable for carrying out the present invention. In the figure, 1 ... Air to be treated containing a malodorous component, 2 ... Exhaust fan, 3 ... Clean Air, 4 ... Clean air control valve, 5 ... Malodorous component measuring device, 6 ... Controller, 7 ... Heat exchanger, 8 ... Thermometer, 9 ... Catalyst, 10 ... Reaction tower, 11 ... ... treated air.

Claims (4)

[Claims] 1. A deodorizing device in which air to be treated is ventilated through a reaction tower filled with a catalyst to cause catalytic oxidative decomposition, and a measuring device for detecting the concentration of a malodorous component in the air to be treated, and detection by the measuring device. When the concentration exceeds a predetermined concentration, clean air is introduced from an introducing device to adjust the clean air to a predetermined concentration or less, and the air to be treated adjusted by the adjusting valve is adjusted to a predetermined temperature. A deodorizing device having a heat exchanger, which ventilates the air to be treated into a reaction tower filled with a catalyst. 2. The apparatus according to claim 1, wherein the catalyst is a composite oxide solid catalyst containing MnO ₂ and CuO as active components. 3. The apparatus according to claim 1, wherein the measuring device for detecting the concentration of the malodorous component in the air to be treated is composed of a metal heat wire type semiconductor gas sensor. 4. The device according to claim 1, wherein the clean air introducing device comprises a measuring device for detecting the concentration of the malodorous component and a clean air adjusting valve for adjusting the introduced amount of the clean air.