JPH11216331A - Deodorizing device - Google Patents

Abstract

(57) [Problem] To configure a deodorizing device for removing hydrogen sulfide in an odorous gas, to eliminate the need for replenishment of activated carbon and to stabilize the deodorizing efficiency. SOLUTION: At the bottom of a washing tower 1 having an odor gas inlet 4 formed at a lower part and a deodorizing gas outlet 7 formed at an upper part, a chemical liquid circulation tank 10 for storing caustic soda 5 and activated carbon 9 is provided with an oxygen supply means 15. A spray nozzle 6 for dispersing the storage liquid in the tank circulated and supplied from the chemical liquid circulation tank 10 is disposed in a tower between the odor gas inlet 4 and the deodorizing gas outlet 7. A flat membrane type ultrafiltration membrane device 11 for separating the activated carbon 9 from the liquid stored in the tank and extracting the caustic soda effluent 13a is immersed in a chemical solution circulation tank 10 inside or outside the washing tower 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deodorizing apparatus used in a human waste treatment facility or the like.

[0002]

2. Description of the Related Art Conventionally, in a night soil treatment facility, a deodorizing method has been carried out in accordance with the process shown in the flow chart of FIG. Is removed to a predetermined concentration, the primary processing gas Y discharged to the outside of the tower is supplied to the acid washing tower 2 to neutralize and remove ammonia and amines, and the secondary processing gas Z discharged to the outside of the tower is alkali- Hydrogen sulfide, mercaptan and methyl sulfide are supplied to the sodium hypochlorite washing tower 3 to oxidize and absorb and remove them.

[0003] The alkali / activated carbon slurry washing tower 1 is as shown in FIG. 4, in which high-concentration odor gas X is supplied from an odor gas inlet 4, and caustic soda 5 (activated carbon) circulated and supplied from the bottom of the tower. Slurry) spray nozzle 6
Hydrogen sulfide in odor gas X and caustic soda 5
Is reacted on the filler 12, whereby the primary processing gas Y from which hydrogen sulfide has been removed is discharged from the deodorizing gas outlet 7, and the reaction product between the hydrogen sulfide and the caustic soda 5 passes through the bottom of the column to the settling tank 8. And the reaction proceeds further by the catalytic action of the powdered activated carbon 9 in the presence of oxygen.
The caustic soda 5 (activated carbon slurry) is circulated to the bottom of the tower by a circulation pump, and the remaining activated carbon 9 is recovered in the settling tank 8. The reaction in the alkali / activated carbon slurry washing tower 1 is represented by the following reaction formula.

[0004]

Embedded image

Since the concentration of hydrogen sulfide is reduced at this stage, it is not necessary to keep the concentration of sodium hypochlorite high in the alkali / sodium hypochlorite washing tower, and the amount of sodium hypochlorite and caustic soda used is reduced. Can be reduced. Therefore, the chlorine odor after the deodorizing treatment is also reduced.

[0006]

However, since the activated carbon used in the above method is a fine powder, the activated carbon partially flows out together with the blow water 13 when fresh water is replenished for adjusting the salt concentration. There was a drawback that the catalyst concentration was reduced and the deodorization efficiency was reduced. Therefore, it was necessary to replenish the activated carbon regularly.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a deodorizing apparatus which does not require replenishment of activated carbon and has a stable deodorizing efficiency.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a deodorizing apparatus for removing hydrogen sulfide in an odor gas, wherein an odor gas inlet is formed at a lower portion and a deodorant gas is formed at an upper portion. At the bottom of the washing tower having an outlet formed therein, a chemical solution circulating tank for storing caustic soda and activated carbon is provided with oxygen supply means, and the column between the odor gas inlet and the deodorizing gas outlet is provided in the tower. A spray nozzle for dispersing the storage liquid in the tank circulated and supplied from the chemical liquid circulation tank is provided, and in a chemical liquid circulation tank inside or outside the washing tower, activated carbon is separated from the liquid stored in the tank to extract caustic soda effluent. A membrane type ultrafiltration membrane device is immersed and installed.

According to the above construction, when removing hydrogen sulfide in the presence of an activated carbon catalyst and oxygen in the same manner as in the prior art, the activated carbon catalyst is retained in the chemical circulation tank by the ultrafiltration membrane device. Is substantially unnecessary, and the deodorizing efficiency is stabilized under a certain catalyst concentration. Further, since no settling tank is required, the apparatus can be made compact.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. In the embodiment shown in FIG.
The difference from the conventional deodorizer of FIG. 4 is that, instead of providing a sedimentation tank outside the alkali / activated carbon slurry washing tower 1, two tanks are installed over the inside and outside of the washing tower 1 and communicate with the bottom. Is provided, and a flat membrane type ultrafiltration membrane device 11 is immersed in a tank 10 a located outside the washing tower 1. As the ultrafiltration membrane 11, p
Those having durability with respect to the alkaline solution of H10 to H11 are used. Numeral 14 is a liquid supply means for supplying fresh water and caustic soda 5 for adjusting the salt concentration to the chemical liquid circulation tank 10, and 15 is an air supply means for supplying an oxygen-containing gas.

According to this deodorizing apparatus, the reaction utilizing the catalytic action of the powdered activated carbon 9 is mainly performed in the tank 10b located inside the washing tower 1, and the mixed liquid in the tank 10b is transferred from the bottom to the tank 10a. The liquid flows in and is solid-liquid separated by the ultrafiltration membrane device 11 by being sucked by the vacuum pump. The caustic soda effluent 13 a corresponding to the conventional blow water permeates the membrane surface and is discharged to the outside of the chemical solution circulation tank 10. As a result, the powdered activated carbon 9 remains in the chemical circulation tank 10.

As in the embodiment shown in FIG. 2, the role of injecting the oxygen-containing gas into the air diffuser 16 provided below the flat membrane type ultrafiltration membrane device 11 for forming a membrane sweep. Is convenient.

[0013]

As described above, according to the present invention, since the activated carbon catalyst is held in the chemical liquid circulation tank by using the ultrafiltration membrane in the catalyst recovery device, the replenishment of the catalyst is substantially unnecessary. However, stable deodorizing treatment can be performed. Further, since there is no need to provide a settling tank, the apparatus can be made compact. Further, the work environment is improved because the supply operation of the activated carbon fine powder is not required.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a deodorizing device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a modified embodiment of the deodorizing device of FIG.

FIG. 3 is a flowchart showing a conventional deodorizing method.

FIG. 4 is a sectional view showing a conventional deodorizing device.

[Explanation of symbols]

 4 Odor gas inlet 5 Caustic soda 6 Spray nozzle 7 Deodorizing gas outlet 9 Activated carbon 10 Chemical liquid circulation tank 11 Ultrafiltration membrane device 13a Caustic soda drainage 15 Air supply means

Claims (1)

[Claims] 1. A deodorizing apparatus for removing hydrogen sulfide in an odor gas, wherein caustic soda and activated carbon are provided at the bottom of a washing tower having an odor gas inlet formed at a lower portion and a deodorized gas outlet formed at an upper portion. A spray for dispensing a storage liquid in the tank circulated and supplied from the chemical circulation tank in a tower between the odor gas inlet and the deodorization gas outlet, provided with a chemical circulation tank for storing the oxygen supply means. A nozzle is arranged, and a flat membrane type ultrafiltration membrane device that separates activated carbon from the storage liquid in the tank and extracts caustic soda effluent is immersed and installed in the chemical circulation tank inside or outside the washing tower. Deodorizing device.