JP3497718B2 - Contaminated air purification device - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to automobiles and factories or tunnels contaminated air purifying apparatus you purify contaminated air by exhaust gas discharged from the various machines construction, details contained in the polluted air carbon dioxide, on nitrogen oxides and pollution air purifier that can effectively remove dust and the like.

[0002]

2. Description of the Related Art Conventionally, a filter type air purifying device has been used as a polluted air purifying device, but the cost is high and it is troublesome to remove the filter from clogging with dust. There is a problem of this. Regarding the removal of nitrogen oxides in exhaust gas,
The dry reduction method, non-contact reduction method or oxidation absorption method is generally known, but the treatment plant by these methods has high construction cost and running cost. There is a problem that the scale becomes large and the cost is considerable. Therefore, an object of the present invention is to provide a polluted air purifying apparatus that can effectively remove carbon dioxide, nitrogen oxides, dust, and the like at low cost.

[0003]

In order to achieve the above object, the polluted air purifying apparatus according to claim 1 comprises a container, and a soil layer housed in the container, in which microorganisms can propagate and air can flow. , An upper part of the soil layer is housed in the container, an activated carbon layer in which air can flow, and an air flow part for passing contaminated air to the soil layer and the activated carbon layer from below the soil layer , Above the soil layer in the container
Water supply provided to supply water downward
Part and below the soil layer in the container, the gas
And water can flow and dust in the contaminated air adheres
Provided in the water-permeable layer and at the bottom of the container or in the vicinity of the bottom
From the water supply section through the soil layer and the permeable layer.
And a drainage part for draining the flowing water.
Between the bed and the activated carbon bed, only gas without passing water
It is characterized by the provision of a water-permeable ventilation layer that allows water to pass through .

According to the polluted air purifying apparatus of the first aspect , polluted air is passed from below the soil layer to the soil layer and the activated carbon layer by the air flow section. Then, dust contained in the contaminated air adheres to the soil particles in the soil layer in the container, and decomposes harmful substances such as carbon dioxide and other carbides and nitrogen oxides into harmless substances by microorganisms in the soil. . Further, among the nitrogen oxides in the contaminated air, the nitrogen oxides that have not been treated in the soil layer and are left to be adsorbed in the activated carbon layer can sufficiently treat the nitrogen oxides without lowering the treatment efficiency. Therefore, it is possible to purify the contaminated air at low cost by effectively removing carbon dioxide gas, nitrogen oxides, dust and the like in the contaminated air with a simple configuration.

Further, water is supplied to the soil layer from the water supply section.
Supply of soil to the soil as contaminated air passes through.
The water that evaporates evaporates and the microorganisms decrease when dried.
Without decreasing the efficiency of decomposition of harmful substances by microorganisms.
prevent. Also, nitrogen dioxide contained in pollutants dissolves in water
It is easy to do and it dissolves in water and changes to nitrous acid and nitric acid.
The treatment efficiency of nitric oxide is improved. Furthermore, it is included in contaminated air.
After the dust that has accumulated is attached to the permeable layer or soil layer,
By the water flowing from the water part through the soil layer and the permeable layer
It can be washed off and drained to the outside by the drainage part.

[0006] Further , the above-mentioned impermeable aeration layer allows the above-mentioned soil
Water enters the activated carbon layer from the layer side to absorb nitrogen oxides, etc.
It is possible to prevent the efficiency from decreasing.

Further, the polluted air purifying apparatus according to claim 2 is the polluted air purifying apparatus according to claim 1 , wherein the activated carbon layer is
It is characterized by a soil-mixed activated carbon layer in which activated carbon is mixed with soil in which microorganisms can reproduce.

According to the polluted air purifying apparatus of claim 2 , the activated carbon layer is a soil-mixed activated carbon layer in which activated carbon is mixed with a soil in which microorganisms can grow, so that harmful substances such as nitrogen oxides are activated carbon. At the same time it can be adsorbed, it can be further decomposed into harmless substances by microorganisms in the soil of the soil-mixed activated carbon layer.

The polluted air purifying apparatus according to claim 3 is the polluted air purifying apparatus according to claim 1 or 2 , wherein the water flowing from the water supply portion through the soil layer and the water permeable layer is used as the water permeable layer. It is characterized in that an opening / closing valve is provided in the drainage section so that it can be stored in.

According to the polluted air purifying apparatus of the third aspect, the on-off valve provided in the drainage section is closed, water is stored in the water permeable layer, and the stored water is stored for an appropriate period. After the on-off valve is opened and discharged, the on-off valve is closed again to store water. Then, by replacing the stored water for an appropriate period, the dust adhering to the water permeable layer can be dissolved in the stored water and discharged outside the container.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The polluted air purifying apparatus of the present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 is a cross-sectional view of a polluted air purifying apparatus according to an embodiment of the present invention, in which 1 is a steel container, 2 is a bottom 1a in the container 1, and gravel with a grain size of about 40 mm is high. 30c
The gravel layer 3 spread over the m is a support layer in which the gravel with a particle size of 3 to 13 mm is spread over the gravel layer 3 to a height of 20 cm, and 4 is the support layer 3 in which soil in which microorganisms can grow is high. A soil layer spread over 50 cm, 5 is provided on the soil layer 4 in the container 1, and a water-impermeable gas-permeable gas-permeable layer, and 6 is water-permeable gas-permeable layer 5 having activated carbon spread on it. It is the activated carbon layer. The soil layer 4 is a mixture of horticultural soil, mulch, oil cake and artificial lightweight aggregate in a volume ratio of 10: 1: 0.5: 1.

Further, a plurality of air supply pipes 13 (only one is shown in FIG. 1) are arranged substantially horizontally in the gravel layer 2 in the container 1. Contaminated air is sucked in by the air pump 11,
The contaminated air is supplied to the plurality of air supply pipes 13 while controlling the flow rate of the contaminated air sent by the air pump 11 by the flow rate controller 12. The air pump 11, the flow rate controller 12, and the air supply pipe 13 constitute an air flow section. Further, the plurality of air supply pipes 13 in the container 1 are respectively provided with a plurality of exhaust ports 13a on the lower side, and the contaminated air from the flow rate controller 13 is discharged to the gravel layer 2 from the plurality of exhaust ports 13a. And flows upward in the container 1. In addition, a plurality of water supply pipes 23 (only one is shown in FIG. 1) as water supply units are arranged substantially horizontally above the soil layer 4. One end of each of the water supply pipes 23 on the upstream side is connected to the water tank 21 via an opening / closing valve 22. The water tank 21 is arranged at a position higher than the position where the water supply pipes 23 are arranged in the container 1. At the inside of the container 1 of each of the water supply pipes 23, a plurality of water supply ports 2 are provided on the lower side.
3a are provided respectively, and water is supplied from the water tank 21 and dripped into the soil layer 4 from the water supply port 23a of the water supply pipe 23. Further, a drainage pipe 15 as a drainage portion having an opening / closing valve 16 is provided on the side surface near the bottom portion 1a of the container 1.
The drain pipe 15 may be provided at the bottom 1a of the container 1.

FIG. 2 is a sectional view taken along the line II--II of FIG. 1, in which a plurality of air supply pipes 13 having exhaust ports 13a are arranged in parallel with each other in the gravel layer 2 in the container 1 at predetermined intervals. is doing. Further, a plurality of water supply pipes 23 having water supply ports 23a are arranged in parallel with each other on the upper side of the soil layer 4 and the lower side of the water-permeable and air-permeable layer 5 at predetermined intervals. The water dripped from the water supply ports 23a of the plurality of water supply pipes 23 flows in the container 1 in the order of the soil layer 4, the support layer 3 and the gravel layer 2 while spreading substantially uniformly, and then accumulates in the lower part of the container 1. It becomes the stored water 14.

In the contaminated air purifying apparatus having the above structure, the contaminated air sucked by the air pump 11 is adjusted to a predetermined amount by the flow rate controller 12 and is sent out to the air feeding pipe 13 to be fed to the air feeding pipe 13. Exhaust port 1
It is discharged to the gravel layer 2 in the container 1 from 3a. Then, the contaminated air flows upward through the gaps of the gravel of the gravel layer 2 and flows into the soil layer 4 through the gaps of the gravel of the support layer 3. At this time, the dust contained in the contaminated air adheres to the gravel of the gravel layer 2 and the support layer 3 and also to the soil particles below the soil layer 4. Further, when the contaminated air passes through the soil layer 4, the carbon dioxide and other carbides and nitrogen oxides in the contaminated air are decomposed by microorganisms in the soil. In this case, the flow controller 12 controls the soil layer 4 of the contaminated air so that most of the carbon dioxide gas is treated in the soil layer 4.
Adjusting the passage rate at the temperature leaves an untreated portion of nitrogen oxides. Then, the contaminated air passes through the activated carbon layer 6 from the soil layer 4 through the impermeable aeration layer 5 and exits upward. At this time,
In the activated carbon layer 6, the nitrogen oxide remaining without being treated in the soil layer 4 is adsorbed on the activated carbon, and also decomposed by microorganisms in the soil.

An experiment using a polluted air purifying device in a tunnel mine will be described below. In the tunnel mine, toxic gas and dust are generated for a long period of time during the slipping and spraying work. The removal characteristics of toxic gas and dust when the toxic gas and dust are removed using the polluted air purifier in this tunnel pit will be described. In this experiment, 0.5 liters per day was dripped from the upper part of the soil layer 4 from the water supply ports 23a of the plurality of water supply pipes 23 of the above-mentioned polluted air purifying device, and water was added to the gravel layer 2 below the container 1. It was stored at a water depth of 15 cm and replaced every two weeks. In addition,
The water-impermeable and air-permeable layer 5 between the soil layer 4 and the activated carbon layer 6 was not provided, and the case where the portion of the activated carbon layer 6 was only soil and the case of soil-mixed activated carbon were compared.

First, FIG. 3 shows the relationship between the linear velocity (the velocity at which contaminated air moves through soil etc.) and the CO removal rate, and the linear velocity and C.
It is a figure which shows the relationship with O density | concentration difference (CO density | concentration before processing-CO density | concentration after processing). As shown in FIG. 3, the linear velocity is 5,1.
CO concentration difference at 0,15 mm / sec is about 5,3,2 pp
The m and CO removal rates were about 88.6, 56.6, 41.1%. Therefore, it was confirmed that the removal performance was practical when the linear velocity was 5 mm / sec.

FIG. 4 is a graph showing the relationship between the linear velocity and the NO removal rate. As shown in Fig. 4, when there is no activated carbon layer (in Fig. 4, the graph without activated carbon added), the linear velocity is 5 mm / sec.
At that time, the NO removal rate was 12.1% at maximum, and the NO removal effect by the soil layer was low. On the other hand, the granular activated carbon was mixed at a volume ratio of 21% from the surface of the soil layer to a depth of 20% and the experiment was continued for 30 days (graph of activated carbon addition in Fig. 4). The removal rate, that is, the NO removal rate after forming the soil-mixed activated carbon layer was 95% or more at any linear velocity.

FIG. 5 is a diagram showing the relationship between the linear velocity and the dust removal rate. As shown in FIG. 5, a high dust removal rate was obtained at any linear velocity. The dust removed at this time migrates to the stored water in the voids of the gravel layer 2 or is trapped under the support layer 3 and the soil layer 4, but because of the porosity of the soil, the dust in the soil layer 4 during the experiment period is No increase in pressure loss was observed.

As described above, the dust contained in the contaminated air adheres to the soil particles in the soil layer 4 in the container 1, and the harmful substances such as carbon dioxide and nitrogen oxides are converted into harmless substances by the microorganisms in the soil. By decomposing and adsorbing, among the nitrogen oxides in the polluted air, the nitrogen oxides that have not been treated in the soil layer 4 and are adsorbed on the activated carbon of the activated carbon layer 6, the nitrogen oxides can be treated without lowering the treatment efficiency. Can also be fully processed. Therefore, it is possible to effectively remove carbon dioxide, nitrogen oxides, dust and the like with a simple configuration, and to purify contaminated air at low cost.

Further, by supplying water to the soil layer 4 from the water pipe 23, it is possible to prevent water contained in the soil from evaporating due to the passage of contaminated air and to prevent the microorganisms from being reduced due to drying, thereby preventing harmful effects of the microorganisms. It is possible to prevent degradation of the decomposition efficiency of the substance. Further, since nitrogen dioxide contained in the contaminated air is easily dissolved in water and dissolved in water to be converted into nitrous acid or nitric acid, the treatment efficiency of nitrogen dioxide can be improved. Further, after the dust contained in the contaminated air adheres to the gravel of the permeable layer of the support layer 3 and the gravel layer 2, the dust that adheres to the gravel by the water flowing from the water pipe 23 through the permeable layer of the support layer 3 and the gravel layer 2 Can be washed away.

An on-off valve 16 provided in the drain pipe 15
Is closed to store water in the gravel layer 2, dissolve the dust adhering to the gravel of the permeable layer of the gravel layer 2 and the support layer 3 into the stored water, and open the on-off valve 16. Can be discharged to the outside of the container 1.

Further, an impermeable aeration layer 5 that allows only gas to pass but not water is provided between the soil layer 4 and the activated carbon layer 6, and the water supplied by the water pipe 23 is fed from the soil layer 4 side. By preventing the activated carbon from entering the activated carbon layer 6, it is possible to prevent the absorption efficiency of nitrogen oxides and the like from being reduced by the activated carbon.

In the above embodiment, the activated carbon layer 6 is laid on the uppermost part of the container 1, but the activated carbon layer may be a soil-mixed activated carbon layer in which activated carbon is mixed with soil in which microorganisms can grow. In this case, the soil-mixed activated carbon layer in which the soil in which the microorganisms can reproduce can be mixed with the activated carbon adsorbs harmful substances such as nitrogen oxides on the activated carbon in the soil-mixed activated carbon layer, and the microorganisms in the soil in the soil-mixed activated carbon layer Hazardous substances can be further decomposed into harmless substances. Further, the mixing ratio of the soil and the activated carbon in the soil-mixed activated carbon layer may be set appropriately.

In the above embodiment, the polluted air extinguishing apparatus for purifying the polluted air in the tunnel mine has been described, but the present invention is applied to purify the exhaust gas discharged from various machines in automobiles and factories. You may apply.

[0026]

As is clear from the above, the polluted air purifying apparatus according to the invention of claim 1 has a container, a soil layer housed in the container, in which microorganisms can propagate, and air can flow, housed in the upper side of the soil layer into the container, and an air is flowable activated charcoal layer state, and are not passing contaminated air into the soil layer and the activated carbon layer from the bottom of the soil layer by the air flow section, Installed above the soil layer in the container
With the water supply part installed, water flows downward.
The gas stored under the soil layer in the container
The dust in the contaminated air adheres to the water-permeable permeable layer.
And at the bottom of the container or near the bottom.
Soil layer and water permeability from the above water supply section
Drains the water that has flowed through the bed and
The impermeable aeration layer provided between the soil layer and the activated carbon layer,
Ru der lets through only the gas without passing through the water.

Therefore, according to the polluted air purifying apparatus of the first aspect of the present invention, the dust contained in the polluted air adheres to the soil particles in the soil layer in the container, and at the same time, the carbon dioxide and other carbides and nitrogen oxides. By decomposing harmful substances such as substances into harmless substances by microorganisms in the soil, and further adsorbing nitrogen oxides remaining in the polluted air that have not been treated in the soil layer in the activated carbon layer. Since both carbides and nitrogen oxides can be processed without reducing the processing efficiency,
With a simple structure, carbon dioxide, nitrogen oxides, dust, etc. can be effectively removed, and polluted air can be purified at low cost.

In addition, it is installed above the soil layer in the container.
With the water supply part installed, water flows downward.
The gas stored under the soil layer in the container
The dust in the contaminated air adheres to the water-permeable permeable layer.
And at the bottom of the container or near the bottom.
Soil layer and water permeability from the above water supply section
The water flowing through the bed is drained, so
Supply of water from some parts of the soil
The water contained in the layer evaporates and the microorganisms decrease due to drying
Of the efficiency of decomposition of harmful substances by microorganisms
In addition to preventing deterioration, nitrogen dioxide contained in pollutants
Easily dissolves in water and dissolves in water to change to nitrous acid or nitric acid
It improves the treatment efficiency of nitrogen dioxide,
After the dust contained in is attached to the permeable layer or soil layer,
By the water flowing from the water part through the soil layer and the permeable layer
Dust can be washed out and drained from the drainage unit to the outside.
Wear.

Further, between the soil layer and the activated carbon layer
The impermeable ventilation layer provided on the
The water supplied by the water supply section
The activated carbon is prevented from seeping into the activated carbon layer from the loam layer side.
To prevent the absorption efficiency of nitrogen oxides, etc. from decreasing due to
be able to.

Further, the polluted air purifying apparatus of the invention of claim 2 is the polluted air purifying apparatus of claim 1 , wherein the activated carbon layer is a soil-mixed activated carbon layer in which activated carbon is mixed with soil in which microorganisms can propagate. It is possible to adsorb harmful substances such as nitrogen oxides on activated carbon, and at the same time, further decompose them into substances harmless by microorganisms in the soil of the soil-mixed activated carbon layer.

Further, the polluted air purifying apparatus of the invention of claim 3 is the polluted air purifying apparatus of claim 1 or 2 , wherein the water flowing from the water supply section through the soil layer and the permeable layer is Since the on-off valve is provided in the drainage portion so that the water can be stored in the water-permeable layer, by closing the on-off valve, water is stored in the water-permeable layer and dust adhering to the water-permeable layer is stored. It can be discharged to the outside of the container by dissolving it in water and opening the on-off valve.

[Brief description of drawings]

FIG. 1 is a sectional view of a polluted air purifying apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a diagram showing a relationship between a linear velocity and a CO removal rate in an experiment using the above polluted air purifying apparatus.

FIG. 4 is a diagram showing a relationship between a linear velocity and an NO removal rate in an experiment using the above polluted air purifying apparatus.

FIG. 5 is a diagram showing a relationship between a linear velocity and a dust removal rate in an experiment using the polluted air purifying apparatus.

[Explanation of symbols]

1 ... container, 2 ... gravel layer, 3 ... Support layer, 4 ... Soil layer, 5 ... Water-permeable ventilation layer, 6 ... Activated carbon layer, 11 ... Air pump, 12 ... Flow controller, 13 ... air supply pipe, 14 ... reserved water, 15 ... drain pipe, 16 ... open / close valve, 21 ... Water tank, 22 ... On-off valve, 23 ... Water pipe.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI B01D 53/56 B01D 53/34 116A 53/81 (56) Reference JP-A-8-299749 (JP, A) JP-A-7 -299325 (JP, A) JP 5-4020 (JP, A) JP 62-97628 (JP, A) JP 7-24242 (JP, A) JP 5-4019 (JP, A) ) JP-A-10-128043 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B01D 53/34-53/85

Claims (3)

(57) [Claims] 1. A container, a soil layer contained in the container, in which microorganisms can propagate, and air can flow, and an activated carbon layer contained in the container above the soil layer and in which air can flow. When an air flow section for passing contaminated air from below the soil layer and the soil layer and the active carbon layer is provided on the upper side of the soil layer of the vessel, downwardly
And a water supply unit that supplies water so that the gas and water are stored under the soil layer in the container.
Water-permeable layer that is flowable and to which dust in the contaminated air adheres
And provided near the bottom of the container or the bottom,
Flow from the water supply through the soil layer and the permeable layer
A drainage part for draining incoming water is provided, and water is not passed between the soil layer and the activated carbon layer.
A contaminated air purifying device, which is provided with an impermeable aeration layer that allows only gas to pass through . 2. The polluted air purifying apparatus according to claim 1 , wherein the activated carbon layer is a soil-mixed activated carbon layer in which activated carbon is mixed with soil in which microorganisms can grow. 3. The polluted air purifying apparatus according to claim 1 or 2 , wherein the water flowing from the water supply section through the soil layer and the permeable layer can be stored in the permeable layer. A polluted air purifier characterized by having an opening / closing valve in the drainage section.