JP2002172154A - Deodorant and deodorizing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of rapidly removing the odors generated from the activated sludge, excess sludge, digested sludge, flocculated sludge, or the like, in waste water or generated in treating the waste water or the cleaning water of a cleaning equipment or the mixture composed thereof with a smaller amount of chemicals in an exhaust duct and sustaining the effect by a solidified deodorant. SOLUTION: The method for deodorizing waste gases containing at lease one kind among hydrogen sulfide and mercaptans includes a process step of neutralizing the waste gas with a neutralizer and a process step of treating the gas with a guanidine base composed and/or quaternary ammonium compound. Further, the deodorizing method includes a process step of treating the gas with a powder deodorant, such as activated carbon or added and stuck activated carbon. The deodorant consists of the neutralizer, the guanidine base compound and/or the quaternary ammonium compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deodorant and a deodorizing method, and more particularly to an improvement in a deodorant and a deodorizing method for exhaust gas containing an odor containing at least one of hydrogen sulfide and mercaptans.

[0002]

2. Description of the Related Art The amount of general wastewater from households has been rapidly increasing with the recent increase in population in cities and suburbs. Therefore, the maintenance of sewerage is urgently required, and the amount of wastewater is increasing year by year. These wastewaters contain large amounts of organic and inorganic substances and are treated at sewage treatment plants. In these wastewater treatment facilities, for example, sewage treatment facilities, an initial sedimentation tank for sedimenting solids in sewage flowing into the sewage treatment facility (hereinafter referred to as inflow sewage), and aeration for aerobically treating organic substrates in the sewage with microorganisms. It has a tank (aeration step) and a final sedimentation tank for separating sludge generated in the aeration step, and treats inflow sewage. A part of the sludge separated from the final sedimentation basin is returned to the aeration tank as returned sludge, and the rest is sent to the first settling tank as surplus sludge and treated as the first settling tank drawn sludge. In these processes, a unique odor is generated and activated sludge, surplus sludge, digested sludge and the like are produced.

[0003] In addition, in the case of factories and other business establishments, due to severe environmental pollution of rivers and oceans, wastewater regulations have been strengthened and it is obligatory to treat water to a predetermined quality. Activated sludge treatment also produces odor and produces a large amount of sludge.

[0004] As described above, odor is generated in the process of treating general household wastewater, wastewater from business establishments and wastewater, and the produced sludge contains various organic and inorganic substances.
Further, various organic and inorganic substances are also contained in the cleaning water of the cleaning device and the like. Also, in such a sewage treatment facility, even in the process of treating sludge, microorganisms in the sludge generate sulfur-based odorous substances such as hydrogen sulfide and mercaptan, thereby causing odor problems and facility corrosion problems. are doing.

[0005] Among these various organic and inorganic substances,
Contains sulfur compounds. Sulfate is generated in the process of these decay. Sulfate-reducing bacteria are usually present in sludge, and sulfate is reduced to hydrogen sulfide in sludge for production activities. By generating hydrogen sulfide, the sludge is further anaerobic, the sulfate-reducing bacteria proliferate, and the amount of generated hydrogen sulfide further increases. The generated hydrogen sulfide is released to the gas phase. Hydrogen sulfide is a toxic and unpleasant odor substance, which is not only dangerous for workers, but also causes odor problems to the local residents. In addition, hydrogen sulfide is oxidized by sulfur oxidizing bacteria and air adhering in concrete facilities, and dissolves in the mist to generate sulfuric acid. The sulfuric acid produced in this way corrodes concrete and metal, causing fatal defects in the structure of buildings.

On the other hand, in recent years, when excavating soil covered with concrete or asphalt for a long time in a suburb of a city, a similar odor has become a problem, and deodorization and deodorization are performed simultaneously during excavation.

As a means for preventing the generation of these odors and the corrosion of structures, there is an activated carbon treatment for adsorbing hydrogen sulfide on activated carbon. However, when the amount of adsorption reaches saturation, it is necessary to replace the activated carbon with new activated carbon or regenerate it. However, there is also a problem in economics such as complicated replacement work and high regeneration cost.

[0008] As another method, there is a method of deodorizing by passing a biologically packed phase held on a carrier. However, this method has problems such as an increase in size of the apparatus and difficulty in maintaining and managing living things.

As a method using a chemical, there is a method in which hydrogen peroxide is spray-mixed, and hydrogen sulfide and mercaptans can be removed in a short time, which is effective. However, in order to maintain the removal effect, the chemical is continuously used. If the amount of the spray mixture is small, sterilization of sulfate-reducing bacteria cannot be performed sufficiently.If sludge is left for a long time, oxidized sulfur or sulfuric acid is required. There is a problem that ions generate hydrogen sulfide again by the sulfate-reducing bacteria.

As a method of fixing hydrogen sulfide as a metal salt, there is a method of spray-mixing a salt (powder) containing an alkali metal. In this method, hydrogen sulfide reacts with metal ions, and a large amount of sludge is formed as metal sulfide. However, there is a drawback that it is generated.

[0011]

In the prior art, the removal of hydrogen sulfide and mercaptans is inadequate, the maintenance is complicated, and there is a problem in terms of economy. The present invention
It is an object of the present invention to provide a deodorizing method and a deodorant for efficiently removing and removing hydrogen sulfide and mercaptans in exhaust gas containing odor under mild conditions to prevent the spread of malodor and the corrosion of facilities.

[0012]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the method of removing odor from exhaust gas containing odor, and as a result, the exhaust gas containing odor containing hydrogen sulfide and mercaptans is first neutralized. After the neutral region is reached, a cationic compound such as a quaternary ammonium salt or a guanidine compound is mixed by a gas-liquid mixing method, and then moisture in the gas phase is removed by an eliminator or the like. The present inventors have found that hydrogen sulfide and mercaptans in exhaust gas containing odor can be efficiently removed by passing the gas, and that the removal can be sustained, thereby completing the present invention.

That is, the deodorizing method of the present invention is a deodorizing method for exhaust gas containing an odor containing at least one of hydrogen sulfide and mercaptans. And / or a step of treating with a liquid deodorant comprising a quaternary ammonium compound. It is preferable to perform a step of treating with a guanidine-based compound and / or a quaternary ammonium compound after or simultaneously with the step of neutralizing with a neutralizing agent. In addition, the deodorizing method of the present invention preferably includes a step of further processing the treated exhaust gas with a powder deodorant.

In the deodorizing method of the present invention, the step of treating with a liquid deodorant is preferably performed by a gas-liquid mixing method by spraying.

In the deodorizing method of the present invention, it is preferable that the powder deodorant used in the step of treating with the powder deodorant is activated carbon or impregnated activated carbon obtained by impregnating activated carbon.

Further, the deodorizing method of the present invention comprises the steps of:
It is suitable for deodorizing exhaust gas generated from a cleaning device or discharged soil during soil excavation.

In the deodorizing method of the present invention, the guanidine-based compound is represented by the following general formula (I) or (I)
The compounds represented by I) and salts thereof with acids are preferred.

Embedded image (Wherein, X is HN =, represents the following general formula (1) or general formula (2), Y is _{H-, NC-, H 2 N-,} HO-,
The following general formula (3) or general formula (4) is represented)

Embedded image

Embedded image

Embedded image (Wherein, R is an alkylene group having 20 or less carbon atoms;
Means a positive number less than or equal to 20)

In the deodorizing method of the present invention, the quaternary ammonium compound is preferably any one of the following general formulas (III) to (V).

Embedded image (R ¹ , R ² , R ³ and R ⁴ represent a straight-chain or branched alkyl group having 20 or less carbon atoms, and may be the same or different)

[0019]

Embedded image (R ¹ and R ² represent a linear or branched alkyl group having 20 or less carbon atoms and may be the same or different)

Embedded image (R ¹ and R ² represent a linear or branched alkyl group having 20 or less carbon atoms and may be the same or different)

The deodorant of the present invention is a deodorant for exhaust containing an odor containing at least one of hydrogen sulfide and mercaptans, which comprises a neutralizer, a guanidine compound and / or a quaternary ammonium compound. It is characterized by containing. Another deodorizing method of the present invention includes a step of treating with the above deodorant.

[0021]

Next, the method of the present invention will be described specifically. The exhaust gas containing an odor according to the present invention includes general wastewater from homes, wastewater from factories and the like, and wastewater generated from washing water and the like contained in a washing device and the like. Furthermore, sludge that generates odor includes raw sludge, excess sludge, digested sludge, coagulated sludge, and the like, and mixtures thereof generated when treating sewage, human waste, or industrial wastewater.

According to the present invention, exhaust containing these odors is
(1) neutralization, (2) treatment with a cationic compound represented by a quaternary ammonium salt compound or a guanidine compound by gas-liquid mixing, and (3) dehydration treatment with a powder deodorant after removing water. It is an odor and deodorization method.

In the method according to the present invention, the odor component in the exhaust gas is treated with a cationic compound such as a quaternary ammonium salt compound or a guanidine compound after the neutralization step. For the neutralizing agent used in the method according to the invention, if the target malodor is acidic, ammonia, triethanolamine,
Treat with an alkaline substance such as an aqueous solution of potassium hydroxide or aqueous sodium hydroxide. On the other hand, when the target odor is alkaline, it is preferable to treat with hydrogen peroxide, peracetic acid, persulfate, percarbonate, perborate, other inorganic or organic peroxides or organic acids. The amount of the neutralizing agent used is determined by the odor after treatment.
H is adjusted to be 4.5 to 9.5, more preferably 5.5 to 8.5, and used.

In the method according to the present invention, the odor component in the exhaust gas is treated with a cationic compound such as a quaternary ammonium salt compound or a guanidine compound after the neutralization step. For the cationic deodorants used in the method according to the invention, examples of guanidine compounds are the compounds of the general formula (I) or (II) and their salts with acids, quaternary ammonium salt compounds Are compounds represented by the general formulas (III) to (V) and salts thereof.

[0025]

Embedded image

In the general formula (I), X represents HN =, the general formula (1) or the general formula (2).

[0027]

Embedded image

In the general formula (I), Y is H-, NC
—, H ₂ N—, HO—, general formula (3) or general formula (4)
Represents

[0029]

Embedded image

For example, the above-mentioned salts may be salts of carbonic acid, nitric acid, sulfuric acid, hydrochloric acid, silicic acid, phosphoric acid, formic acid and / or acetic acid. Further, a biguanidine polymer represented by the following general formula (II) may be used.

[0031]

Embedded image (Wherein, R is an alkylene group having 20 or less carbon atoms;
Means a positive number less than or equal to 20)

[0032]

Embedded image (R ¹ , R ² , R ³ and R ⁴ represent a straight-chain or branched alkyl group having 20 or less carbon atoms, and may be the same or different)

[0033]

Embedded image (R ¹ and R ² represent a linear or branched alkyl group having 20 or less carbon atoms and may be the same or different)

[0034]

Embedded image (R ¹ and R ² represent a linear or branched alkyl group having 20 or less carbon atoms and may be the same or different)

The use of the powder deodorant is intended to maintain the deodorizing effect of the quaternary ammonium salt compound or the guanidine compound and to realize a higher degree of deodorizing effect by the deodorizing effect of the powder deodorant itself. The present inventors have studied powder deodorants, and have found that activated carbon and various types of impregnated activated carbon exhibit a sustained deodorizing effect as well as a deodorizing effect.

The neutralizing agent and the cationic deodorant may be separately mixed in gas and liquid or may be mixed at the same time. In addition, a mixture obtained in advance may be gas-liquid mixed. When mixing in advance, a chelating agent such as an ethylenediamine-based or organic carboxy-based stabilizer can be spray-mixed. Further, the mixture may be sequentially spray-mixed. The order of the spray-mixing is not particularly limited, but it is preferable to mix the neutralizing agent first.

In order to carry out the method according to the invention efficiently,
When the neutralizer and the cationic deodorant are gas-liquid mixed, it is preferable that the deodorant is mixed with the entire odor efficiently in mixing with the exhaust containing the odor, but as a mixing method used at that time, Using a nozzle or chip that generates mist, the exhaust stream is swirled or turbulent to hit the mist, a chamber is provided, etc., to reduce the flow rate to increase deodorizing efficiency, or to supply nozzles and other deodorants. There is a method such as increasing. There is also a method of continuously bringing a liquid phase into contact with a gas phase, such as an eliminator. Any method may be used as long as the exhaust gas containing the odor can be mixed with the neutralizing agent and the cationic deodorant.

As a method of mixing the chemicals by a spraying method, any method such as a diaphragm type or a plunger type metering pump may be used as long as it can accurately supply the chemicals.

In order to carry out the method according to the invention efficiently,
As for the place where the gas-liquid mixing of the drug is performed, immediately after the exhaust is preferable in view of the reaction time until the release into the atmosphere, but if the effect is recognized, the gas-liquid mixing may be performed in any step.

The powder deodorant composition of the present invention is molded as necessary and used as a molded article. As means for molding, extrusion molding, tablet molding, rolling granulation, compression molding and the like are preferable. The shape of the molded body is determined according to the purpose of use and the method of use. Examples of the shape of the molded body include a columnar shape, a crushed shape, a spherical shape, a honeycomb shape, an uneven shape, and a corrugated plate shape. In particular, when the odorous gas is positively brought into contact with the deodorizing composition by a fan or the like to be adsorbed and removed, it is preferable to use the filter as a filter or a honeycomb filter in which a molded article such as a mesh or corrugated sheet is appropriately combined. .

[0041]

Next, the method of the present invention will be described more specifically with reference to examples. However, the present invention is not limited by these examples. The percentages in the examples are% by weight unless otherwise specified.

Prior to the examples, an apparatus for a deodorizing test will be described. A schematic diagram is shown in FIG. Exhaust gas containing the odor of sludge is obtained from the aeration tank 10, and the neutralizing agent 12 is sprayed through the nozzle 26 by the pressurizing pump 16 and mixed with the exhaust gas containing the odor. Next, the deodorant 14 is sprayed through the nozzle 28 by the pressurizing pump 18 and mixed with the exhaust gas containing the odor. Then, excess water is removed by eliminator 2
0, is sent to the powder deodorant cartridge 24 by the exhaust fan 22, and is discharged as deodorized exhaust. In the present invention, evaluation was performed using such a schematic device.

Prior to the examples, the sensory evaluation criteria of the deodorization evaluation test are shown below. <Deodorizing evaluation test: sensory evaluation> Panel for sensory evaluation (n = 8) for deodorized exhaust gas obtained in each deodorizing effect test
Was used to perform a sensory evaluation. For sensory evaluation,
The exhaust was guided from the duct to the 5 L odorless bag, and the judgment was made. The judgment was made according to the judgment table in Table 1 below. Sensors were also measured from this bag.

[0044]

[Table 1] Odor intensity evaluation criteria  5 Intense smell 4 Strong smell 3 Easy to perceive and recognize 2 Clearly feel (understand what smell) 1 Feel slightly (understand smell; threshold density)0 Do not feel (odorless)

The present inventors have attempted to improve the deodorizing effect by combining a liquid deodorant with a deodorizing method using activated carbon as a powder deodorant, which has been an incomplete deodorizing method in the past.

Example 1 An aeration tank containing 200 ppm of hydrogen sulfide was exhausted from an exhaust duct (600 mm × 600 mm, air velocity 5
m / s), circulating an aqueous solution of trimethylamine as a neutralizing agent by eliminator treatment to adjust the gaseous phase pH to 5.5, and then distearyl dimethyl ammonium chloride (quaternary ammonium salt compound) per 100 liters of exhaust gas.
The deodorant liquid previously mixed so as to be 5 ml and 15 ml of a 20% aqueous solution of biguanidine was spray-mixed with exhaust gas by a nozzle in an amount of 100 ml per minute. Excess water was distilled off from the exhaust gas by an eliminator. Sensory values after passing through the eliminator and changes over time of the odor sensor manufactured by Futaba Electronics Corporation were measured. Further, a deodorizing test was carried out according to Example 1 by changing the medicine and the powder deodorant. The chemicals and their amounts are shown in Table 2 and the results are shown in Table 3.

[0047]

[Table 2] Chemical addition amount (ml / 100 liter) vs. sludge exhaust  Neutralizer 20% diesteraryldimethyl powder deodorant(Trimethylamine) ammonium compound ammonium chloride  Example 1 250 15 5 Activated carbon Example 2 250 0 20 Activated carbon Example 3 250 200 Impregnated activated carbon (honeycomb-shaped) Example 4 250 200 Impregnated activated carbon (corrugated plate) Comparative example 1 250 00 Activated carbon Comparative example 2 250 0 0 Activated carbon impregnated (honeycomb) Comparative Example 3 2500 Activated carbon impregnated (corrugated) Comparative Example 4 000 Activated carbon Comparative Example 5 200 Activated carbon

[0048]

[Table 3]  Measured value (immediately) Measured value (after half an hour)  pH sensory sensor pH sensory sensor(* 1) Indicated value (* 2) (* 1) Indicated value (* 2)  Example 1 5.5 1.5 250 5.5 1.4 210 210 Example 2 5.5 1.6 230 5.6 1.5 1.5 240 Example 3 5.6 1.4 250 5.6 1.3 220 Example 4 5.5 1.5 270 5.5 1.4 260 260 Comparative Example 1 5.8 3.9 1120 5.7 5.4 1810 Comparative Example 2 5.7 4.3 1230 5.7 5.7 0 1770 Comparative Example 3 5.7 4.4 1260 5.6 4.9 1800 Comparative Example 4 1.7 5.2 2390 1.6 5.3 2460 Comparative Example 5 1.3 5.2 2500 2500 2.4 .9 2180  * 1 Sensory value (average of n = 8) 6-level evaluation method * 2 Sensor reading (Futaba Electronics)

From the results shown in Table 3, it can be seen that Examples 1-4, which were treated with a guanidine compound and / or a quaternary ammonium compound after charging the neutralizing agent and then treated with activated carbon, had excellent deodorizing effects, and even after 30 minutes. It can be seen that the effect has continued.
In addition, when no liquid deodorant was mixed with gas and liquid after adding the neutralizing agent (Comparative Examples 1 to 3), the sensor indicated value showed a tendency to decrease in comparison with the blank (Comparative Example 4). In the judgment, a bad smell was strong, and after 30 minutes, the sensory value and the indicated value of the sensor tended to be bad. This is considered to be due to the fact that the amount of adsorbed odor of activated carbon as a powder deodorant tended to be saturated. Although it seems that there is also a problem with the amount of the powder deodorant used in the test, the system using only the powder deodorant has a longer effect on the effect than the examples because the effects of Examples 1 to 4 were maintained. Seems short. Further, as shown in Comparative Examples 4 and 5, in the system using the liquid deodorant and the powder deodorant without the neutralizing agent, the acidic state of the exhaust was maintained, and the effect of the deodorant was hardly recognized. . It can be said that neutralization is necessary in order to effectively remove hydrogen sulfide and deodorize.

Next, it was examined how much a deodorizing effect can be obtained without using a powder deodorant. The test method is in accordance with Example 1. Table 4 shows the chemicals and the amounts added, and Table 5 shows the results.

[0051]

[Table 4] Chemical addition amount (ml / 100 liter) vs. sludge exhaust  Neutralizer 20% diesteraryldimethyl powder deodorant(Trimethylamine) ammonium compound ammonium chloride  Example 6 250 0 0 None Example 7 250 0 20 None

[0052]

[Table 5]  Measured value (immediately) Measured value (after half an hour)  pH sensory sensor pH sensory sensor(* 1) Indicated value (* 2) (* 1) Indicated value (* 2)  Example 6 5.4 2.8 400 5.5 2.2 320 Example 7 5.4 3.1 570 5.4 3.0 3.0 550

From the results shown in Table 5, it can be seen that Examples 6 and 7 can reduce the offensive odor, but are inferior in sensory evaluation as compared with Examples 1 to 4 including the treatment with the powder deodorant. In the examination on the duration of the effects shown in Table 5, Examples 1-4 were more effective than at the beginning of the experiment, but such effects were not observed. Therefore, when it is necessary to further improve the deodorizing effect, it is preferable to add a treatment step using a powder deodorant.

[0054]Examination of spraying method of drug  Next, the present inventors conducted a neutralization treatment step,
Deodorizing effect by separately performing the treatment process with the compound
I checked if it would affect me.

Example 8 An aqueous ammonia solution as a neutralizing agent was circulated from an aeration tank containing 200 ppm of hydrogen sulfide as an eluentator to an exhaust duct (600 mm × 600 mm, air velocity 5 m / s, gas phase pH 1.7). After adjusting the gaseous phase pH to 5.7, about 20 ml of a 20% aqueous solution of biguanidine per 1 liter of exhaust gas was added at a rate of about 1 minute per minute.
The mixture was spray-mixed with a nozzle in an amount of 00 ml. Excess water was distilled off from the exhaust gas by an eliminator. Sensory values after passing through the eliminator and changes over time of the odor sensor manufactured by Futaba Electronics Corporation were measured. In the blank, untreated exhaust gas was measured in the same manner, and the sensor indicated value was 3000 and the sensory value was 5.9.

Example 9 An aeration tank containing 200 ppm of hydrogen sulfide was introduced into an exhaust duct (600 mm × 600 mm, air velocity 5 m / s, gas phase pH 1.7), and 160 ml of an aqueous ammonia solution was used as a neutralizing agent for a 100 liter displacement. , 20%
Was spray-mixed by a nozzle in an amount of 20 ml of the aqueous solution of biguanidine. Hereinafter, the same as Example 8 was used. The chemicals and their amounts are shown in Table 6 and the results are shown in Table 7.

[0057]

[Table 6] Chemical addition amount (ml / 100 liter) vs. sludge exhaust  Neutralizer 20% powder deodorant(Ammonia water, reagent grade) Guanidine compound  Example 8 (separate spray) 160 ml / 100 liter (odor) 20 ml / 100 liter (odor) activated carbon 100 kg Example 9 (formulation) 160 ml / 100 liter (odor) 20 ml / 100 liter (odor) activated carbon 100 kg

[0058]

[Table 7]  Measured value (immediately) Measured value (after 30 minutes)  pH sensory sensor pH sensory sensor(* 1) Indicated value (* 2) (* 1) Indicated value (* 2)  Example 8 (separate spray) 5.7 2.2 250 5.6 1.3 220 Example 9 (formulation) 5.4 2.5 260 5.5 1.5 230  * 1 Sensory value (average of n = 8) 6-level evaluation method * 2 Sensor reading (Futaba Electronics)

From the results shown in Table 7, it can be seen that both in the case of formulation and in the case of spraying each agent separately, the malodor is removed immediately after the addition, and the effect can be maintained thereafter.

[0060]Long-lasting deodorant effect  Next, the long-term persistence of the deodorizing effect of the present invention was examined.
Debated. Deodorizing methods of Examples 8 and 6 and Comparative Examples 4 and 5
The deodorizing effects after one month were compared. Drugs and their
Table 8 shows the amount of addition, and Table 9 shows the results.

[0061]

[Table 8] Chemical addition amount (ml / 100 liter) vs. sludge exhaust  Neutralizer 20% powder deodorantGuanidine compound  Example 8 160 (aqueous ammonia) 20 activated carbon Example 6 250 (trimethylamine) 20 None Comparative Example 4 0 0 Activated carbon Comparative Example 5 0 20 Activated carbon

[0062]

[Table 9]  Measured value (immediately) Measurement value (one month later)  pH sensory sensor pH sensory sensor(* 1) Indicated value (* 2) (* 1) Indicated value (* 2)  Example 8 5.7 2.2 250 5.6 1.3 220 220 Example 6 5.4 2.8 260 5.5 5.5 2.7 230 Comparative Example 4 1.7 5.2 1190 1.6 5.9 2700 Comparative Example 5 1.3 5.2 1.2 1200 1.2 4.9 1090  * 1 Sensory value (average of n = 8) 6-level evaluation method * 2 Sensor reading (Futaba Electronics)

From the results shown in Table 9, it can be seen that the deodorizing method of the present invention (Examples 8 and 6) in which treatment with a neutralizing agent is followed by treatment with a guanidine compound is also excellent in long-term deodorizing effects. Understand. On the other hand, it can be seen that the deodorizing method according to Comparative Example 4 or Comparative Example 5 without the neutralization treatment is inferior in both the deodorizing effect immediately after and the deodorizing effect after one month. In addition, comparing Example 8 with Example 6, it can be seen that Example 8 in which the activated carbon treatment is performed is superior in the deodorizing effect, especially in the functional value after one month.

[0064]

According to the deodorizing method of the present invention, hydrogen sulfide,
In a method for deodorizing exhaust gas containing an odor containing at least one of mercaptans, the method includes a step of neutralizing with a neutralizing agent and a step of treating with a guanidine-based compound and / or a quaternary ammonium compound. Hydrogen sulfide, which is a malodorous component, can be removed, and the deodorizing effect on hydrogen sulfide can be maintained. Further, the deodorizing effect is further improved by adding a powder deodorant treatment step. According to the present invention, hydrogen sulfide in exhaust gas can be quickly deodorized and continuously deodorized. Further, a deodorant containing a neutralizing agent and a guanidine compound and / or a quaternary ammonium compound is provided.

[Brief description of the drawings]

FIG. 1 is a schematic view of a test apparatus for a deodorizing method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Aeration tank 12 Neutralizer 14 Liquid deodorant 16, 18 Pressure pump 20 Eliminator 22 Exhaust fan 24 Powder deodorant cartridge 26, 28 Nozzle

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4C080 AA05 AA06 BB02 CC04 CC05 CC12 HH03 HH05 JJ04 KK06 KK08 LL02 MM05 MM18 QQ20 4D059 AA03 AA05 BK03 DA01 DA31 DA35 DA38 DA44 DB21 DB26

Claims (10)

[Claims] 1. A method for deodorizing an exhaust gas containing an odor containing at least one of hydrogen sulfide and mercaptans, wherein the step of neutralizing with a neutralizing agent and a liquid comprising a guanidine compound and / or a quaternary ammonium compound A deodorizing method comprising a step of treating with a deodorant. 2. The method according to claim 1, wherein after the step of neutralizing with the neutralizing agent or simultaneously with the step of neutralizing,
A deodorizing method comprising a step of treating with a guanidine compound and / or a quaternary ammonium compound. 3. The deodorizing method according to claim 1, further comprising the step of treating the treated exhaust gas with a powder deodorant. 4. The deodorizing method according to claim 1, wherein the step of treating with a liquid deodorant is performed by a gas-liquid mixing method by spraying. 5. The deodorizing method according to claim 3, wherein the powder deodorant used in the step of treating with the powder deodorant is activated carbon or impregnated activated carbon obtained by subjecting activated carbon to impregnation. How to deodorize. 6. The deodorizing method according to claim 1, wherein the exhaust gas containing the odor to be treated is exhaust gas generated from wastewater, sludge, a washing device, or discharged soil during soil excavation. . 7. The deodorizing method according to claim 1, wherein the guanidine compound is represented by the following general formula (I) or (I)
A deodorizing method, which is a compound represented by I) or a salt thereof with an acid. Embedded image (Wherein, X is HN =, represents the following general formula (1) or general formula (2), Y is _{H-, NC-, H 2 N-,} HO-,
Represents the following general formula (3) or (4): Embedded image Embedded image (Wherein, R is an alkylene group having 20 or less carbon atoms;
Means a positive number less than or equal to 20) 8. The deodorizing method according to claim 1, wherein the quaternary ammonium compound is any one of the following general formulas (III) to (V). Embedded image (R ¹ , R ² , R ³ and R ⁴ represent a linear or branched alkyl group having 20 or less carbon atoms, and may be the same or different.) (R ¹ and R ² represent a linear or branched alkyl group having 20 or less carbon atoms, and may be the same or different.) (R ¹ and R ² represent a linear or branched alkyl group having 20 or less carbon atoms and may be the same or different) 9. A deodorant for exhaust containing odor containing at least one of hydrogen sulfide and mercaptans, wherein the deodorant contains a neutralizing agent and a guanidine compound and / or a quaternary ammonium compound. Odorant. 10. A deodorizing method comprising a step of treating with the deodorant according to claim 9.