JPS607923A - Apparatus for deodorizing odorous gas by soil - Google Patents

Abstract

PURPOSE:To dispense with a heating apparatus for heating an odorous gas by insulating a blower and a duct for sucking the odorous gas with a heat insulating material, and heating the odorous gas with the heat generated from the operation of the suction blower. CONSTITUTION:A suction blower 7 is installed in an insulated chamber 13 constructed of a heat insulating material 12, and a duct 14 is insulated with a heat insulating material 12'. An odorous gas 10 is discharged into a cobblestone layer 3 from discharge ports 5 of a gas pipe 6 through the suction blower 7 and the duct 14. The odorous gas 10 is heated with the heat generated from the operation of the suction blower 7, dispersed while passing through the cobblestone layer 3 and a gravel layer 2, deodorized by a soil layer 1, and discharged into the atmosphere from the surface of the soil layer 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides soil-based deodorization of malodorous gases, which can deodorize malodorous gases generated, for example, in municipal waste composting plants, using microorganisms in the soil, especially in cold regions. It is related to the device.

There are combustion methods, chemical cleaning methods, activated carbon adsorption methods, ion exchange resin methods, ozone oxidation methods, masking methods, etc. to treat foul-smelling gases, but in recent years cities have started to use composting plants for livestock manure, livestock waste processing plants, etc. The soil-based deodorization method is used to deodorize foul-smelling gases generated from plants, etc.

This is a layer of soil such as black soil, field topsoil, or compost on top of a lower layer of gravel, etc.
Deodorizing treatment is performed through a chemical neutralization reaction between soil components and malodorous substances in the soil, or through the decomposition action of microorganisms such as microorganisms in the soil.

However, in cold regions, when the soil temperature drops below about 5 degrees Celsius, the microorganisms become dormant and their ability to decompose malodorous substances almost disappears. .

The current situation is that during the extremely cold season, when the outside air temperature is about -300 degrees Celsius, the soil freezes and the equipment cannot operate.

The present invention was developed in view of the above point t, and it maintains soil temperature by extremely simple means to a level that does not reduce the ability of microorganisms to decompose malodorous substances, even in cold regions. The purpose is to provide a deodorizing device using soil W for foul-smelling gas that maintains deodorizing performance.

In other words, the gist is that a suction blower is installed in an insulated chamber made of heat insulating material, and a duct piping is connected to the suction blower to draw out the malodorous gas heated by the heat generated by the blower's suction operation. The duct piping is insulated with heat insulating material, and a gas pipe with many exhaust holes is connected to it.The gas pipe is buried in a cobblestone layer, and a gravel layer is placed on top of the cobblestone layer. Above is a soil-based deodorizing device J for foul-smelling gas, which is made up of layers of soil.

The configuration shown in the figure will be explained.

Drill a hole (9) in the ground (8) and surround it with concrete blocks (4) (4') (4'') (4'). ) (4'') (4') is not limited to a quadrangle, but may be a polygon or a circle J cedar.

(3) is the cobblestone layer laid at the bottom in the excavation hole (9), (2) is the gravel layer laid above it, and (1) is the top soil layer.

The cobblestone layer (3) has a gas discharge hole (5) and a conduit (6).
is being buried.

On the other hand, (13) is a storage room with a suction blower (
1) Completely installed 11 (14') is a duct piping that brings out the malodorous gas (lo) f sucked by the suction blower (1), and is connected to the suction blower (-1), and the duct piping (14"l)
i Connect to the gas conduit (6).

(12) is a heat insulating material forming an insulating room (13), (12"
) indicates the heat insulating material of the duct pipe (14).

Each insulation material (12) (12') is an asbestos insulation material, a rock wool insulation phase, an ore cotton insulation phase, a glass fiber insulation material, a diatomaceous earth insulation phase, etc., and its thickness is determined by the temperature of the malodorous gas itself. and the temperature force S of the surrounding air.

(11) indicates odorless gas that has been deodorized.

The effect will be explained.

Now, to explain the case where this is installed in a municipal waste composting plant, the malodorous gas (10) generated from the plant is guided from the suction blower (7) to the gas pipe (6) via the duct pipe (14). is discharged from its discharge hole (5) into the cobblestone layer (3), but in this case, the suction blower (
7) is installed in the insulating room (13), and the Talito piping (14)
) is kept warm by a heat insulating material (12'). The malodorous gas (10) is heated by the amount of heat generated during the suction operation of the R blower (7) itself. Therefore, the same gas (1o) is
Even in cold regions, the output of the blower (7) is about 30 to 50
The temperature at which the gas is discharged from the gas discharge hole (5) of the gas conduit (6) into the cobblestone layer (3) is approximately 20 to 40C.

This foul-smelling gas (1o) discharged into the cobblestone layer (3) is
While passing through the upper gravel layer (2), it is dispersed and reaches the soil layer (1).

Apparent flow velocity of malodorous gas (1o) dispersed in soil layer (1), size 7! In other words, the malodorous gas (1o) in the soil layer (1)
) The ventilation rate is between 3 and 20 degrees.

During this time, malodorous substances are adsorbed to the soil and deodorized, and the same layer (
From the surface of 1), it becomes an odorless gas (11) and is released into the atmosphere.

As mentioned above, the temperature of the foul-smelling gas (10) is about 20-40"C at the point where it is discharged from the gas discharge hole (5) into the cobblestone layer (3) even in a cold area, so it is The temperature of (1) is maintained at about 6-180C and it never drops below about 5"C.

/L To heat the foul-smelling gas (1o), it is possible to pass it through an electric heater, storage oil heater, etc., but if the equipment is properly kept warm, a suction blower ('7
) This is not necessary since the amount of heat generated by itself can be sufficient for heating.

Microorganisms in soil that decompose malodorous gas (10) include:
Nitrite bacteria that oxidize ammonia to nitrite, nitrate bacteria that oxidize nitrite to nitric acid, sulfide bacteria that decompose sulfides such as hydrogen sulfide, methyl mercaptabe, methyl sulfide, 1T acid, propionic acid, There are actinomycetes that decompose lower fatty acids such as butyric acid and valeric acid, and acidophilus and yeast that decompose tx'F acid, but the temperature at which these microorganisms can grow is approximately 5 -
60.0 and becomes dormant below about 5C.

However, in the present invention, since the temperature of the malodorous gas (10) is high even in cold regions, the temperature of the soil layer (1) is not lowered below about 5C.

In other words, even in cold regions, the soil temperature should be kept at about 6-18
This makes it possible to deodorize without weakening the decomposition power of microorganisms such as bacteria in the soil.

Next, one experimental example will be explained.

The main malodorous substances and their concentrations in the malodorous gas generated from the composting plant were as follows.

Ammonia 40 ppm (same below), trimethylamine 0.1, hydrogen sulfide 0.01. Methyl mercaptan 0.
004. Methyl sulfide 0.04. Methyl disulfide 0.00
5. Acetoacidehyde a, 9s, pactic acid L43, propionic acid 0.0946, inbutyric acid Q, Q636, n butyric acid 0.
0B'y4, isovaleric acid 0.0856, nvaleric acid 0. Q
O68, isocabayaic acid 0.05B, inbutyraldehyde 0.150% methyl sinter z1.3. Echi Echi + b5
．． 63゜Ethanol 178, nproper tool 1.3
B, methyl ethyl ketone 1.55, α-pinene 0.39.
β-pinene 0.0B, limonene 8.4Q, impentane 0.046, tosien O+081 Such foul-smelling gases (lO) were collected at a thickness of 500 m, m from the cobblestone layer (3).

Gravel layer (2) thickness 200m, m.

Thickness of soil layer (1) 600 m, m.

When operated under these conditions, Table 1 shows the operating results in a cold region when the conventional suction blower was not installed in the insulating room and when the device of the present invention was used.

Appearance, 1. The quantitative limit value for ammonia is 1 ppm2, and the odor concentration is measured by the three-point comparison odor bag method.According to this, in the conventional method, when the outside air temperature is -100, the temperature of the malodorous gas is slightly reduced by 4 eyebrows when the blower is operated. However, it is 100 in the duct at the entrance of the deodorizing equipment, and O''' in the deep soil layer.
In the shallow part of C1, it decreases to -20. As a result, a malodorous gas with an ammonia concentration of 40 ppm was deodorized to only 20 ppm, and the odor concentration was reduced from 4000 to 2000.

This is not a value that can be completely satisfied with the odor concentration of 300, which is not regulated by the Tokyo Metropolitan Pollution Prevention Ordinance for exhaust outlets in Class F1 areas (residential areas, etc.).

This 1 (on the other hand, with the method of the present invention, even if the outside air temperature is as low as -180 degrees, the inside of the duct at the entrance of the deodorizing equipment is 3 o"
c, and the temperature in the deep part of the soil layer is 12" o, and even in the shallow part it is 8" o.
C, the ammonia concentration is not detected, and the malodorous gas with an odor vacancy value of 3500 is 150.The effect will be explained below.

In order to prevent the heat of the malodorous gas heated by the suction operation of the malodorous gas suction blower from escaping, the present invention houses the malodorous gas suction blower in an insulating chamber made of a heat insulating material, and also insulates the duct piping with a heat insulating material. This heated and heat-retained malodorous gas is released into the soil layer through the cobblestone layer and gravel layer, which immediately eliminates the need for a malodorous gas heating device, reducing facility costs and maintenance and operation costs. In addition, the deodorizing effect of malodorous gas is extremely good, and the effect can satisfy even strict city ordinances.

[Brief explanation of drawings]

FIG. 1 is a plan view of the present device, and FIG. 2 is a longitudinal sectional side view taken along the line A--A in FIG. 1. l... Soil layer 2... Gravel layer 3... Cobblestone layer 5... Discharge hole 6... Gas pipe 7...
Suction blower 10... Malodorous gas 12,12'...
・・Heat insulation material 13・・・・Insulation room 14・・Duct piping patent applicant Co., Ltd. Japan Wooden Steel Works

Claims (1)

[Claims] A suction blower is installed in an insulating chamber made of heat insulating material, and a duct piping is connected to the suction blower to draw out the malodorous gas heated by the heat generated by the suction operation of the blower. At the same time as keeping it warm, a gas pipe with many discharge holes is connected to this, and the gas pipe is buried in a cobblestone layer.A gravel layer is placed on top of the cobblestone layer, and a soil layer is placed on top of that. A deodorizing device that uses soil to remove foul-smelling gas.