JPH0299117A - Gas deodorizing apparatus - Google Patents

Abstract

PURPOSE:To enhance treatment capacity by arranging a plurality of deodorizing towers in parallel to the flow direction of gas to be treated and immobilizing bacteria on a packed bed while connecting a feed and drain pipe of washing water to the lower part of each deodorizing tower. CONSTITUTION:Gas 10 to be treated flows in deodorizing towers 11-14 in parallel through a feed-in duct 18 and passes through the first packed bed of each deodorizing tower to be reversed in the lower part of said tower and further passes through the second packed bed 17 to be discharged as odorless treated gas 10a from the discharge duct 19 provided to the upper part of the deodorizing tower. When the gas 10 to be treated passes through the first and second packed beds 16, 17, the malodorous component contained in said gas is decomposed and removed by the biological deodorizing action of immobilized bacteria. By this method, a lowering in the removal ratio of the malodorous component occurring from the short pass of the gas to be treated during washing can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gas deodorizing device using microorganisms, and more particularly to an improvement in a cleaning device for a packed bed in which microorganisms are immobilized.

[Prior Art] In recent years, biological deodorization methods have been attracting attention as gas deodorization methods that are low in processing cost and free from the risk of secondary pollution.

In particular, various biological deodorization methods are under development in which microorganisms are immobilized in a packed bed, which enables space-saving and highly efficient deodorization.

When microorganisms are immobilized in a packed bed, in order to maintain the activity of the microorganisms and prevent changes in the bacterial flora, it is necessary to periodically supply water to the microorganisms, and to ensure that the microorganisms decompose and assimilate malodorous components contained in the gas. It is necessary to wash away the various products generated during this process.

An example of a cleaning device in a conventional biological deodorization method is shown in the fourth example.
This will be explained using figures. In the figure, 1 is a deodorizing tower, inside which there are multiple packed beds 2 in which packed materials (carriers) (not shown) are stacked, and microorganisms are fixed on the surface of the carriers in each packed bed 2. has been done. Reference numeral 3 denotes a water spraying device provided to periodically sprinkle water on the packed bed 2 in each stage, and a pump 5 is installed in the washing water tank 4 provided at the bottom of the deodorizing tower 1.
A water supply pipe 6 connected via a water supply pipe 6, a branch pipe 8 branched from the water supply pipe 6 to each stage via a valve 7, and a large number of nozzles 9 for jetting cleaning water attached to the branch pipe 8. It is configured.

Next, its operation will be explained. The gas to be treated 10 is fed from the lower part of the deodorizing tower 1, and while rising and passing through the packed bed 2 of each stage, it is brought into contact with the microorganisms immobilized on the surface of the carrier, and the microorganisms contained in the gas to be treated 10 are removed. Decomposes malodorous components. Products generated as a result of decomposition in the packed bed 2 of each stage are washed away from the surface of the carrier by periodically operating the water sprinkler 3 provided at each stage, for example, starting from the top stage. That is, first, only the valve 7 at the top stage is opened, and the pump 5 pumps the wash water in the wash water tank 4 through the water supply pipe 6 and the branch pipe 8, and the water is jetted from the nozzle 9 to spray water onto the packed bed 2 at the top stage.

Next, after sprinkling water for a certain period of time, the operation of the topmost water sprinkling device 3 is stopped, and the next water sprinkling device 3 is operated in the same manner as described above. Repeat this in order until you reach the bottom. In this way, the packed bed 2 at each stage is cleaned and the microorganisms are supplied with water.

By passing the gas to be treated 10 through the packed beds 2 at each stage, the malodorous components contained therein are removed as described above, and the gas to be treated 10 is
a and is released into the atmosphere from the upper part of the deodorizing tower 1.

[Problems to be Solved by the Invention] The conventional cleaning method for gas deodorizing equipment involves spraying cleaning water while passing the gas to be treated as described above, which has the following problems. there were.

(1) During cleaning, the gas flow area is reduced due to the presence of cleaning water, so a so-called short bath occurs, and the removal rate of malodorous components in the gas to be treated is greatly reduced.

(2) Since cleaning is performed while supplying the gas to be treated, gas flow portions and water flow portions occur within the packed bed, making it difficult to uniformly clean the entire packed bed.

(3) Since the products of microbial reactions are usually acidic, the pH value of the washing water itself decreases as it flows down from the top while washing the packed bed, and the pH value of the washing water itself decreases by washing the entire packed bed. Can not do it.

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, it is an object of the present invention to provide a gas deodorizing device that can perform quick and uniform cleaning and that does not reduce the performance of removing malodorous components during cleaning. It is something.

[Means for Solving the Problems] A gas deodorizing apparatus according to the present invention has a plurality of deodorizing towers arranged in parallel in the flow direction of the gas to be treated, and microorganisms are placed in a packed bed provided in each deodorizing tower. At the same time, each of these packed beds is divided into a first packed bed and a second packed bed by partition walls so that the gas to be treated flows into the deodorizing tower from the top, reverses at the bottom, and then flows out from the top. A washing water supply and drainage pipe is connected to the bottom of the pipe. The processing capacity of each deodorizing tower is determined so that even if one deodorizing tower is being cleaned, the remaining deodorizing towers can process the entire amount of gas to be treated.

[Function] In the gas deodorizing apparatus according to the present invention, the gas to be treated flows from the upper part of each deodorizing tower, passes through the first packed bed, and is reversed at the lower part.
Then, it passes through the second packed bed and exits the deodorizing tower from the upper part. The deodorizing tower is washed by sequentially supplying washing water from the bottom of the deodorizing tower. When the level of the supplied cleaning water reaches the lower edge of the partition wall, the flow of gas to the deodorizing tower is cut off, and the entire amount of the gas to be treated is subjected to microbial decomposition treatment in the deodorizing tower except during cleaning.

Washing is performed by filling the first and second packed beds with washing water up to the upper surfaces. Since the filling bed is filled with cleaning water without gas flow, every corner of the packed bed is thoroughly cleaned.

After cleaning is completed, the cleaning water is extracted all at once and returned to the cleaning water tank, and after water quality adjustment, it is used repeatedly to clean each deodorizing tower.

[Example] Hereinafter, one embodiment of the present invention shown in the drawings will be described in detail.

FIG. 1 is a schematic diagram showing an embodiment of a gas deodorizing apparatus according to the present invention, and shows a case where four deodorizing towers are provided. As shown in the figure, in this embodiment, four deodorizing towers 11
, 12, 13, and 14 are arranged in parallel to the flow direction of the gas to be treated 10. In each deodorizing tower 11 to 14,
The packed bed in which microorganisms are immobilized is divided into a first packed bed 16 and a second packed bed 17 by a partition wall 15, and the gas to be treated 10 flows from the upper part of the deodorizing tower through the partition wall 15, passes through the first packed bed 16, and is separated into a first packed bed 16 and a second packed bed 17. The water is turned over at the bottom, and then flows through the second packed layer 17 so as to exit from the top.

18 is an inlet duct for the gas to be processed 10, and 19 is an outlet duct for the process gas 10a.

A water pipe 21 and a drain pipe 22 are connected to the lower part of each of the above-mentioned deodorizing towers 11 to 14 via a header 20. Water pipe 2
1 and one end of the drain pipe 22 are each connected to a wash water tank 23, and are each equipped with a water pump 24, a water valve 25, a drain pump 26, and a drain valve 27.

The header 20 and each of the deodorizing towers 11 to 14 are connected through a communication pipe 29 provided with a valve 28. A make-up water supply pipe 30, an alkaline agent supply pipe 31, and a discharge pipe 32 are connected to the wash water tank 23, and a pH meter 33 controls the pH value of the wash water to an extent that does not inhibit the activity of microorganisms.

FIG. 2 shows an example of a compact arrangement of the above embodiments, and FIG. 3 is a sectional view taken along line A--A in FIG. 2.

Each element is the same as in Figure 1, so it is given the same reference numeral.

Next, the operation will be explained. The gas to be treated 10 flows in parallel from the upper part of each deodorizing tower 11 to 14 through an inlet duct 18 . The gas then passes through the first packed bed 16, is reversed at the bottom of each deodorizing tower, and further passes through the second packed bed 17, becoming an odorless processing gas 10a and being discharged through one exhaust duct at the top. The gas to be treated 10 is in the first filled layer 16 and the second filled layer 1
7, the malodorous components contained are decomposed and removed by the biological deodorizing action of the immobilized microorganisms as described above.

To explain the case of cleaning one deodorizing tower, for example, the first deodorizing tower 11, water from the cleaning water tank 23 is sent from the lower part of the first deodorizing tower 11 through the water pipe 21 by the water pump 24. The water level of the washing water sent into the deodorizing tower 11 gradually rises from the bottom, and when it reaches the lower edge 15a of the partition wall 15, the flow of gas in the deodorizing tower 11 stops. Further, the water level rises until it reaches the upper surfaces of the first filled layer 16 and the second filled layer 17, and then stops. As a result, the first and second packed beds 16, 17 are completely filled with wash water.

Thereafter, the drain pump 26 draws out the wash water all at once through the drain pipe 22. This wash water is returned to the wash water tank 23. After a certain period of time, the water in the wash water tank 23 is sent to the next deodorizing tower 12 in the same manner as above, and when the first and second packed beds 16 and 17 of that deodorizing tower 12 are completely filled. It is drawn back into the wash water tank 23. Such operations are repeated in order for the third and fourth deodorizing towers 13 and 14. The interval between cleaning from one deodorizing tower to the next is set according to the conditions (concentration, temperature, humidity, flow rate, etc.) of the gas to be treated 10 at the inlet of the deodorizing tower. The time divided by

The water quality of the cleaning water is adjusted when the cleaning water is returned to the cleaning water tank 23, and in order to maintain the concentration of microbial products contained in the cleaning water below a concentration that does not inhibit the activity of microorganisms, it is necessary to adjust the quality of the cleaning water until it reaches a set value. At that point, some of the washing water is discharged, fresh water is replenished, and an alkaline agent for neutralization is supplied.

When cleaning a certain deodorizing tower, when the cleaning water level reaches the lower edge 15a of the partition wall 15, the flow of gas in that deodorizing tower stops. This is done in a deodorizing tower.

[Effects of the Invention] As described above, according to the present invention, in the deodorizing towers arranged in parallel in the flow direction of the gas to be treated, the gas to be treated flows into the deodorizing tower from the upper part of the deodorizing tower and is reversed at the lower part by dividing the packed bed. Further, since the deodorizing tower is divided into first and second packed beds so as to flow out from the upper part, and the cleaning water is sequentially fed and discharged from the lower part of each deodorizing tower, the following effects can be obtained.

(1) During cleaning, the lower inversion section is filled with cleaning water, so no gas to be treated flows into the deodorizing tower during cleaning.

(2) Since the cleaning water spreads to every corner of the packed bed and complete cleaning is possible, the entire surface of each carrier in the packed bed can be effectively used for microbial reactions.

(3) By controlling the pH value of the washing water in the washing water tank for washing, the surface pH of all carriers in the packed bed can be adjusted to the optimum pH value for microorganisms.

Therefore, there is no reduction in the removal rate of malodorous components due to the short path of the gas to be treated during cleaning, which was a problem with conventional techniques in which cleaning was performed while passing gas.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing one embodiment of the gas deodorizing device of the present invention, FIG. 2 is a simplified configuration diagram of the above embodiment, and FIG.
The figure is a sectional view taken along the line AA in FIG. 2, and FIG. 4 is a schematic diagram of a conventional cleaning device. 10... Gas to be treated 11-14... Deodorizing tower 15
...Separation 16...First packed layer 17...
2nd filled bed 21... Water pipe 22... Drainage pipe designated agent Satoshi Suzuki Yujo 3 diagram

Claims (1)

[Claims] A plurality of deodorizing towers are arranged in parallel in the flow direction of the gas to be treated, a packed bed in which microorganisms are immobilized is provided in each deodorizing tower, and the gas to be treated flows into the packed bed from the upper part of the deodorizing tower. The deodorizing tower is characterized by comprising: a partition wall dividing the deodorization tower into a first packed bed and a second packed bed so as to be inverted at the bottom and flow out from the top; and a washing water supply and drainage pipe connected to the bottom of each deodorizing tower. Gas deodorizing equipment.