JP2002018236A - Method for neutralization of acid gas and its apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for neutralization of an acid gas and its apparatus in which contact efficiency of a neutralization liquid with the acid gas is improved and a pump for circulating the neutralization liquid is made unnecessary and there exists no possibility of clogging and corrosion in pipelines and the pump accompanied with formation of by-products. SOLUTION: In the method for neutralization of the acid gas and its apparatus in which the acid gas is introduced into a single or a plurality of gas scrubbers 41, 42 and 43 whose bottom ends are inserted into a neutralization cooling instrument 44 and liquified ingredients of the acid gas are made to flow into the neutralization cooling instrument 44 from the gas scrubbers and are neutralized and cooled, and by spouting high pressure air from air introducing pipes 50, 51 and 52 inserted into the gas scrubbers, the neutralization liquid is sucked by a negative pressure brought about by the high pressure air through guiding-out pipes 47, 48 and 49 and is sprayed in a foggy state into the gas scrubbers 41, 42 and 43 to cool the acid gas ingredients and to accelerate liquidization.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for neutralizing an acid gas generated when a hardly decomposable substance such as an environmental pollutant is decomposed, and particularly to an apparatus having a chlorofluorocarbon gas, polyethylene, plastic or benzene nucleus. The present invention relates to a method and an apparatus for neutralizing an acidic gas generated when decomposing environmental pollutants such as compounds and other industrial wastes.

[0002]

2. Description of the Related Art It has been pointed out that chlorofluorocarbon and halon gas used as a refrigerant and a spray agent are environmental pollutants, and the detoxification of these substances protects the global environment. From a viewpoint, it has become a global concern and various countermeasures have been proposed. For example, as a method for treating CFCs, a hydrothermal reaction method, an incineration method, an explosion reaction decomposition method, a microbial decomposition method, an ultrasonic decomposition method, a plasma reaction method, and the like have been proposed.

[0003] Among these treatment methods, the hydrothermal reaction method is not limited to chlorofluorocarbon gas and the like, but is applicable to all decomposed substances mainly composed of industrial solvents such as organic solvents such as trichlene, waste oil, dioxin, PCB, and manure. On the other hand, it is attracting attention as a versatile processing method. In this hydrothermal reaction method, for example, fluorocarbon gas can be decomposed into a safe substance such as sodium chloride and carbon dioxide.

[0004] Regarding the apparatus for realizing the hydrothermal reaction method, a processing experiment using an autoclave in a laboratory, for example, a mixing ratio of caustic soda solution, ethanol, and fluorocarbon solution, a set value of temperature, a set value of pressure, and a reaction value Experiments have been conducted on the set value of time, but usually the hydrothermal reaction is performed at 300 to 450 ° C. and 100 to 250 (kg / cm ² ).
It is performed while maintaining the high temperature and high pressure conditions.

The applicant of the present application has previously filed Japanese Patent Application No. 11-27618.
According to No. 1, oxygen, or oxygen and water,
Alternatively, by supplying only water as a solvent and passing the same through a normal-pressure reactor heated to a predetermined temperature for a predetermined reaction time, three types of oxidative decomposition, hydrolytic decomposition, and hydrolysis are performed. A proposal was made on a method and an apparatus for decomposing a hardly decomposable substance in which the hardly decomposable substance was decomposed based on any of the decomposition principles or a combination thereof. The contents will be briefly described with reference to the CFC treatment system diagram of FIG. 7. First, CFC is charged into the decomposition target tank 1, and the air compressor 3 and the metering pump 6 are activated to make the CFC and air flow control valves. 2, 4 and pipes 9, 8 are fed into the reactor 7, and at the same time, a fixed amount of water as a solvent is sent from the water tank 5 through the pipe 10 to the reactor 7, and mixed at an appropriate ratio. At this time, each pipe 8, 9,
The preheating is performed by driving the preheating heaters 11, 12, and 13 provided in the reactor 10, and the three heating heaters 14, 15, and 16 provided in the reactor 7 are further driven. The temperature distributions T ₁ , T ₂ , and T ₃ are controlled.

As described above, the preliminary heaters 11, 12, 1
3 and the heaters 14, 15, 16
By heating the inside to a predetermined temperature range,
Anxiety arises. Superheated steam temperature required for decomposition
Since the degree differs depending on the material to be decomposed,
Set according to the processing object. For example, CFC-22
In this case, the air input is 130 (l / min) and water is
3 (kg / h) and 10 (kg / h) of CFC-22
h) and the temperature distribution T in the reactor 7₁, T₂, T ₃To
They are controlled at 950 ° C, 1050 ° C, and 1080 ° C, respectively.
At this time, reduce the amount of air input to 110 (l / min)
And each temperature distribution T₁, T₂, T₃Are 980 ° C,
It changes to 1100 ° C and 1140 ° C. In addition, air injection
When the volume is increased to 150 (l / min), each temperature distribution
T₁, T₂, T₃Are 950 ° C, 980 ° C, 10
Changes to 10 ° C. T₁Temperature changes around 950 ° C
The lower temperature is the target temperature of 950 ° C.
Because it is automatically controlled.

In the reactor 7, CFC-22, which is a substance to be decomposed, reacts with water as a solvent and oxygen in the air while maintaining a predetermined temperature to carry out a hydrolytic decomposition treatment. still,
Depending on the substance to be decomposed, superheated steam at about 300 ° C. may be used, and the temperature is set to an individually suitable temperature according to the substance to be decomposed. The set temperature is not limited as long as the superheated steam can be used. . A predetermined reaction time elapses while the superheated steam passes through the inside of the reactor 7, and the substance to be decomposed in the superheated steam is decomposed into an acidic gas, and together with the liquid component, the next shower through the pipe 25. It is sent into the ring tower 17.

[0008] From the middle of the reactor 7, the air compressor 60
Alternatively, air may be supplied into the reactor 7 using the flow control valve 60a. By supplying air from the middle of the reactor 7 in this way, the oxidation reaction can be promoted by the oxygen in the supplied air, and at the same time, the inside of the reactor 7 can be cooled by the nitrogen in the supplied air. That is, the reactor 7
By replenishing the oxygen lacking therein with air, an oxygen-excess atmosphere is created, and the inside of the reactor 7 can be effectively cooled by nitrogen in the air while replacing carbon monoxide with carbon dioxide.

In the showering tower 17, the acid gas in the decomposition target flows from the teralet 17a through the pipes 26, 18a, 27, and 19a.
The air is exhausted outside through the suction blower 24. The liquid component in the decomposition target material falls from each of the showering towers 17, 18, and 19 into the neutralization cooler 20. The neutralizing cooler 20 is filled with a strong alkali solution such as caustic soda solution or a calcium hydroxide solution, and these neutralizing solutions flow into the cooler 23 from the pipe 20a, and the cooling water of the cooler 23 The cooling water is supplied from the inlet 23a and discharged from the outlet 23b, and is constantly cooled. The neutralizing solution is sent from the pump 21 for showering to the header 22, and is supplied to each of the showering towers 17, 18, 19. The gas component is cooled by the showering inside, and liquefaction is promoted.

By quenching and liquefying the decomposed product in this way, generation of by-products is prevented, and there is no fear of secondary contamination due to release in the gaseous state and scattering into the atmosphere. The quenching is performed to prevent the generation of harmful by-products, because harmful by-products such as dioxin are formed when cooling slowly from high temperature to low temperature. The decomposed matter stored in the neutralizing cooler is periodically discharged through a pipe 28 and sent into a drain tank (not shown). In addition, cooler 2
The temperature in 3 may be any temperature at which the gas component of the decomposition product can be liquefied, and is approximately 25 ° C. for Freon gas.

FIG. 8 is a front sectional view showing another example of the showering towers 17, 18, 19 and the neutralization cooler 20, and FIG. 9 is a sectional side view showing the same. While flowing through each of the showering towers 17, 18, 19 via the pipes 26, 27, the liquefied components in the decomposition target material are removed by the neutralization cooler 2
0, and the neutralized solution stirred by the stirring blades 34a of the stirrer 34 is cooled by the cooling pump 2 from the showering pump 21.
3 into the header 22 and each showering tower 1
Shower in 7,18,19.

In the above description, when performing hydrolysis, only the metering pump 6 is started without starting the air compressor 3 and water to be decomposed and water as a solvent are supplied to the reactor 7 to superheat steam. A predetermined reaction time is allowed to elapse in an atmosphere of superheated steam of the solvent. This method is suitable for decomposing solid substances to be decomposed other than fluid or gas, such as PE, plastic, rubber, wood, paper, and the like. In the case of performing oxidative decomposition, only the air compressor 3 is started without activating the metering pump 6, and the decomposed substance and air are supplied to the reactor 7 to allow a predetermined reaction time to elapse in an oxygen atmosphere. However, since by-products are often formed, it is better to carry out oxidative decomposition in an appropriate amount of superheated steam atmosphere even in this case, and there is no problem of secondary contamination since by-products are not formed. When oxygen gas prepared separately is used instead of air, the decomposition efficiency is improved.

The neutralizing solution is supplied to each of the showering towers 17, 18, 1
9 instead of the method of feeding and
As shown in FIG.
Bubbling tanks 30, 31, 32 installed in multiple stages
The bubbling tanks 30, 31 and 32 are blown into the bubbling tanks 30, 31 and 32 and blown out of the bubbling holes 35 and 35 in the neutralized solution to bubble into the solution, thereby cooling gas components to promote liquefaction and detoxification. A method of exhausting gas to the outside by using a suction blower 33 is also known.

[0014]

As described above, the decomposition means utilizing the hydrothermal reaction has to maintain high temperature and high pressure conditions in the reactor, so that the structures of the reactor and the pressure regulating valve are complicated. In addition, it is difficult to design to withstand mechanical strength, for example, tensile stress or thermal stress, and there is a problem that the material to be used is limited. In addition, the mechanism for pumping and discharging the solid-liquid mixture under high temperature and high pressure is complicated, and it is necessary to change the structure depending on the type of the substance to be decomposed. In some cases, the pipes may be damaged during operation due to the high pressure, and there is still a problem from the viewpoint of ensuring safety.

According to Japanese Patent Application No. 11-276181 proposed above, a substance which is difficult to decompose is reacted in an atmosphere of superheated steam to decompose by thermal decomposition, hydrolysis, reduction reaction, oxidation reaction, or a combination thereof. Although it is effective in that it can be performed, there is a need for improvement as described below. That is, in the showering method shown in FIGS. 7 to 9, the contact efficiency between the neutralizing solution and the acid gas is not always satisfactory, and the showering towers 17, 18, 1 are not always satisfactory.
9. A pump 21 for showering for circulating the neutralizing solution
However, in addition to the disadvantage that corrosion is accelerated by a strong alkali solution such as caustic soda solution or calcium hydroxide solution, or the by-products cause abrasion of the showering pump 21 to shorten service life and increase running costs, Since the operation of the apparatus becomes abnormal due to the pipe clogging phenomenon, complicated maintenance is always required.

As shown in FIG. 7, the showering tower 17,
When the terrarets 17a, 18a, and 19a are disposed in the pipes 18 and 19, the caustic soda or calcium hydroxide crystal at the time of drying adheres to the piping and the pump 21 for showering together with the problem of the by-products. Clogging phenomena may occur, and there is a problem that the operation of removing these is dangerous and difficult to maintain because it must be performed in a strong alkaline atmosphere.

In the bubbling method shown in FIG. 10, when the acidic gas in the decomposition target is bubbled in the neutralizing solution filled in the bubbling tanks 30, 31, 32, the blowing holes 3 are used.
When the diameters of the blowout holes 35 and 35 are small, it is necessary to apply pressure to the reaction gas to perform stable bubbling. Nature occurs. Further, the effect of contact with the neutralizing solution is enhanced by increasing the positions of the blowout holes 35, 35, but there is a problem in that the pressure required for blowing out increases.

In some cases, salt is formed as a by-product during neutralization of the reaction gas.
35 may be clogged, and in a case where the amount of acid gas in the decomposition target material increases, the blowing holes 35,
Since a large number of 35 must be provided, there is a problem that the bubbling mechanism must be increased in size as a whole.

Since the above-described method is an exothermic reaction in which heat of neutralization and heat of dissolution are generated, a separate cooler 23 is provided for the neutralization cooler 20 to cool the gas components of the decomposition products. It is necessary, for example, to attach a cooling tower to the cooler 23 to cool and circulate the cooling water, and to exchange heat with the neutralizing liquid to release the heat. There is a drawback that costs rise. Although the cooling efficiency is improved by adopting the chiller unit, there is a problem that the chiller unit itself is expensive and the running cost is also increased.

Therefore, the present invention solves the above-mentioned problems for neutralizing acid gas generated when decomposing environmentally polluting substances such as chlorofluorocarbons, organic compounds and other industrial wastes. The acid gas that enhances the contact efficiency between the neutralizing solution and the acidic gas and eliminates the need for a pump to circulate the neutralizing solution, and does not cause clogging or corrosion in piping and pumps due to the generation of by-products It is an object of the present invention to provide a neutralization method and an apparatus therefor.

[0021]

According to the present invention, in order to achieve the above object, an acidic gas is introduced into one or a plurality of gas washing towers whose lower end is inserted into a neutralizing cooler. The liquefied component flows into the neutralization cooler from the gas cleaning tower to neutralize and cool, and the high pressure air is blown out from the air introduction pipe inserted into the gas cleaning tower, so that the negative pressure caused by the high pressure air Provided is a method and an apparatus for neutralizing an acidic gas in which a neutralizing solution is sucked through a discharge pipe and sprayed in a mist state in a gas washing tower to cool an acidic gas component to promote liquefaction. .

As a specific configuration, the acidic gas in the object to be decomposed is guided into one or a plurality of gas washing towers whose lower end is inserted into a neutralization cooler to convert a liquefied component of the acidic gas into a gas. By flowing into the neutralization cooler from the washing tower to neutralize and cool, and by blowing high-pressure air from the lower end of the air introduction pipe inserted from above the gas washing tower, the negative pressure caused by the high-pressure air The neutralizing solution is sucked through the outlet pipe and sprayed from the tip of the nozzle in the form of a mist into the gas washing tower, thereby using an acid gas neutralizing method that promotes the liquefaction of the acidic gas component.

The neutralizing cooler and the gas cleaning section are integrated with each other, and a neutralizing solution outlet pipe extends from the inside of the neutralizing cooler to the gas cleaning section. The air introducing pipe is inserted in the horizontal direction, and the end of the air introducing pipe is configured to be close to the upper end of the neutralizing liquid outlet pipe. It is set so that the acidic gas flows in the gas cleaning section in a bypass manner.

In another embodiment, a pipe through which an acidic gas flows is provided at a position slightly separated from the surface of the neutralizing liquid inside the neutralizing cooler, and the pipe extends from the inside of the neutralizing cooler. While extending the outlet pipe of the neutralizing solution toward the small hole opened in, the air introduction pipe is inserted horizontally from the side,
An acid gas neutralizing device is provided in which a nozzle of the air introducing pipe is disposed close to an upper end of a neutralizing liquid outlet pipe and a small hole of the pipe. At one end of the pipe, a drain port for returning the liquid component to the neutralized liquid is provided. Further, a stirring blade driven by a stirrer is provided in the neutralizing cooler.

According to the method and the apparatus for neutralizing the acidic gas, the substance to be decomposed in the superheated steam is decomposed by the reactor, the acidic gas is sent into the gas cleaning tower, and the gas is passed through the pipe. While flowing and being exhausted to the outside from the exhaust port, the liquefied component of the acidic gas flows into the neutralization cooler from the gas washing tower and is neutralized and cooled. Then, the high-pressure air is ejected from the air introduction pipe inserted into the gas cleaning tower, so that the negative pressure caused by the high-pressure air causes the neutralizing liquid to be sucked in the discharge pipe and the nozzle, and the atomized liquid is formed from the tip of the nozzle. The acid gas component is cooled by the spraying of the neutralizing solution, and the liquefaction is promoted. Also, by quenching and liquefying the acid gas, the generation of by-products is prevented, and even if the by-products are generated, they fall directly into the neutralization cooler, which may cause clogging of piping and the like. Absent.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific embodiment of a method and an apparatus for neutralizing an acidic gas according to the present invention will be described below with reference to the drawings. In addition, oxygen, or oxygen and water, or water as a solvent is supplied to a substance to be decomposed such as chlorofluorocarbon, and is allowed to pass through a normal pressure reactor heated to a predetermined temperature after a predetermined reaction time. Thus, a method of decomposing a hardly decomposable substance based on any one of three decomposition principles of oxidative decomposition, hydrolytic decomposition, and hydrolysis or a combination thereof is based on the technical content proposed by Japanese Patent Application No. 11-276181. The same is true, and the present invention is characterized by providing a method for neutralizing a reaction gas, that is, an acid gas, in a decomposition target material flowing out of a reactor.

FIG. 1 is a front sectional view showing a first embodiment of the present invention, and FIG. 2 is a left sectional view of the same.
Reference numeral 43 denotes a gas cleaning tower, and reference numeral 44 denotes a neutralization cooler. Lower ends of the gas cleaning towers 41, 42, and 43 are inserted into the neutralization cooler 44. An inlet 40 of an acid gas, which is an object to be decomposed in a reactor (not shown), is connected to an intermediate portion of a gas cleaning tower 41, and the gas cleaning towers 42, 43 are connected via pipes 45, 46.
It flows inside and is exhausted to the outside through the exhaust port 39. In the neutralizing cooler 44, a stirring blade 34a driven by the stirrer 34 is provided.

Numerals 47, 48, and 49 are outlet pipes for the neutralizing liquid extending upward from the inside of the neutralizing cooler 44 along the respective gas cleaning towers 41, 42, and 43. ,
Nozzles 47a, 48a, 49 connected to the upper end of 49
The leading end of a is inserted into each of the gas cleaning towers 41, 42, 43. 50, 51, 52 are gas cleaning towers 41,
Air introduction pipes inserted from above 42, 43, and lower ends of the air introduction pipes 50, 51, 52 are nozzles 47a,
48a and 49a are arranged close to the tip. The other ends of the air introduction pipes 50, 51, 52 are connected to a high-pressure air source (not shown).

The gas cleaning towers 41, 42 and 43 are devices for separating and cleaning the acid gas of the decomposition target material, and are not limited to the three illustrated ones, but are provided with one or more cleaning towers. . The neutralization cooler 44 cools the obtained liquid component and the neutralized liquid, and the outlet pipes 47, 48, 49 and the nozzle 47
a, 48a, 49a through the gas cleaning towers 41, 42, 4
A circulating mechanism which feeds above 3 to promote liquefaction of the acid gas is constituted.

The operation of this embodiment will be described.
First, when decomposing fluorocarbon gas, which is an environmental pollutant, by hydrolytic decomposition, fluorocarbon and air are sent to a reactor (not shown) via a flow control valve, and at the same time, a certain amount of water as a solvent is supplied to the reactor. Superheated steam is generated inside the reactor by feeding and mixing at an appropriate ratio and controlling the temperature distribution in the reactor. Since the temperature of the superheated steam required for the decomposition treatment varies depending on the decomposition target, each temperature is set according to the decomposition target.

CFCs to be decomposed by the reactor
FC-22 reacts with water in the solvent and oxygen in the air while maintaining a predetermined temperature to carry out a hydrolytic decomposition treatment. Depending on the substance to be decomposed, superheated steam of about 300 ° C. may be used, and the temperature is set individually suitable for the substance to be decomposed. A predetermined reaction time elapses while the superheated steam passes through the reactor, the decomposition target material in the superheated steam is decomposed, and the acidic gas is introduced into the gas cleaning tower 41 from the inflow port 40 shown in FIG. Sent in.

In the gas cleaning tower 41, the acidic gas in the decomposition target flows through the pipe 45, the gas cleaning tower 42, and the pipe 46, and is exhausted to the outside through the exhaust port 39. The neutralizing cooler 44 is previously filled with a strong alkali solution such as caustic soda solution or a calcium hydroxide solution, and the liquefied component of the acid gas flows into the neutralizing cooler 44 from each of the gas cleaning towers 41, 42, and 43. And neutralized and cooled.

By operating a high-pressure air source (not shown), high-pressure air is blown from the lower ends of the air introduction pipes 50, 51, 52 inserted from above the gas cleaning towers 41, 42, 43. Due to the negative pressure caused by the high-pressure air, the neutralizing solution is discharged from the outlet pipes 47, 48, 49 and the nozzles 47a, 48.
a, 49a, the nozzles 47a, 48a, 4
The gas cleaning towers 41 and 4 are atomized from the tip of 9a.
Sprayed in 2,43. By spraying the neutralizing solution, the acidic gas component is cooled, and liquefaction is promoted. By quenching and liquefying the acidic gas, generation of by-products is prevented, and even if by-products are generated, the neutralization cooler 4
Since it falls into 4, it does not cause clogging of piping and the like. Further, there is no fear of secondary pollution caused by releasing the acidic gas in a gaseous state and scattered into the atmosphere.

FIG. 3 is a plan sectional view showing a second embodiment of the present invention, FIG. 4 is a front sectional view thereof, and FIG. 5 is a right sectional view thereof.
In the second embodiment, the neutralizing cooler 44 and the gas cleaning unit 55 are integrated, and the acid gas is set so as to bypass the gas cleaning unit 55 as shown by the arrow A in FIG. ing. Further, four neutralization liquid outlet pipes 47 b and 48 are directed from inside the neutralization liquid of the neutralization cooler 44 to the gas cleaning section 55.
b, 49b and 50b are extended, and the gas cleaning section 5
5, four air inlet pipes 56, 57, 58, 59
Are inserted in the horizontal direction, and the air introduction pipes 56, 57,
The leading end portions of 58 and 59 are connected to neutralizing solution outlet pipes 47b and 48, respectively.
b, 49b and 50b are arranged close to the upper end.
The other end of each of the air introduction pipes 56, 57, 58, 59 is connected to a high-pressure air source (not shown) through a common high-pressure pipe 61.

According to this configuration, while the acid gas in the decomposition target flows bypassing the gas cleaning section 55, the high pressure air source (not shown) is operated to insert the gas from the side of the gas cleaning section 55. By jetting high-pressure air from the distal ends of the air introduction pipes 56, 57, 58, and 59, the neutralized liquid stirred by the stirring blades 34a of the stirrer 34 by the negative pressure generated by the high-pressure air is drawn out. 47b, 48b, 49b, 50b
It is sucked upward through the inside and the outlet pipes 47b, 48b,
The gas cleaning section 5 is formed into a mist from the tip of 49b, 50b.
Sprayed in 5 This spray cools the acidic gas component and promotes liquefaction.

FIG. 6 is a front sectional view showing a third embodiment of the present invention. In the present embodiment, a pipe 62 is provided in the neutralization cooler 44 at a position slightly away from the level of the neutralizing liquid in a lateral direction, and the acidic gas is supplied through the pipe 62 as shown by arrows B and B. It is set to flow inside. The small holes 6 opened in the pipe 62 from inside the neutralization cooler 44
Outgoing pipes 63, 6 for three neutralizing solutions toward 2a, 62a
4 and 65 are extended, and an air introduction pipe 66 is
Are inserted in the horizontal direction, and the nozzles 66a, 66a of the air introduction pipe 66 are arranged close to the upper ends of the outlet pipes 63, 64, 65 for the neutralizing liquid and the small holes 62a, 62a. A drain port 6 for returning the liquid component to the neutralized liquid is provided at one end of the pipe 62.
7 is provided.

According to this configuration, while the acidic gas in the decomposition target flows through the pipe 62, the high pressure air source (not shown) is operated to operate the nozzle 6 of the air introduction pipe 66 inserted from the side.
By jetting high-pressure air from 6 a, the neutralized liquid stirred by the stirring blades 34 a of the stirrer 34 is sucked upward in the outlet pipes 63, 64, 65 by the negative pressure caused by the high-pressure air. It is sprayed in the form of a mist.
This spray cools the acidic gas component and promotes liquefaction. The liquid component is supplied to a drain port 6 provided at one end of the pipe 62.
Return to the neutralizing solution from 7.

The reactor used in the present invention decomposes hard-to-decompose substances such as environmental pollutants such as chlorofluorocarbon gas under normal pressure, and the hard-to-decompose substances of interest are organic compounds and are stable. Although there is no particular limitation, fluorocarbon gas, organic solvent such as trichlene, waste oil, dioxin, PC
B, industrial waste such as manure, wood, paper, rubber and the like, and the state thereof is not particularly limited regardless of whether it is solid, liquid or gas. It is mainly useful as an organic compound, but is difficult to treat after use or harmful, for example, chlorobenzene, freon (halogen carbon compound), dioxin in question, etc., or useful as an organic compound. However, they are extremely stable and not harmful but difficult to process, for example, PE, plastic, rubber and the like.

These are often made from petroleum, and can be almost oily when decomposed, so that they can be used as fuel or decomposed so that they can be recycled. Also,
In the case of rubber, organic compounds are detoxified or decomposed so that they can be recycled.Degradation of paper, wood, etc. decomposes cellulose into glucose to convert it into glucose, and those with low utility value are useful. Can be converted to

[0040]

As described above in detail, according to the present invention, by spraying the neutralizing solution in the form of a mist into the gas cleaning tower, the contact efficiency between the neutralizing solution and the acidic gas is increased, and Since pumps for circulating the neutralizing solution are not required,
The pumps are not likely to be corroded by a strong alkaline solution such as caustic soda solution. Furthermore, by quenching and liquefying the acidic gas, the generation of by-products is prevented, and even if the by-products are generated, they fall directly into the neutralization cooler. The phenomenon of clogging of piping and the like does not occur.

The shapes of the air introduction pipe for blowing out high-pressure air and the discharge pipe and nozzle for sucking and spraying the neutralizing solution are as follows:
Since the normal pipe shape may be used as it is, the configuration of the apparatus is simplified, the phenomenon in which the by-products and the alkali crystals are clogged hardly occurs, and the maintenance becomes easy.

Since the neutralization of an acidic gas is an exothermic reaction that generates heat of neutralization and heat of dissolution, it is necessary to provide a separate cooler for the neutralizing solution in addition to the conventional neutralizing cooler. According to the method described above, since the neutralizing liquid is atomized by blowing out high-pressure air at room temperature, the high-pressure air brings about a cooling effect of the neutralizing liquid, so that it is not necessary to provide a separate cooler. Therefore, the effect of reducing costs and running costs can be obtained.

Therefore, according to the present invention, the efficiency of contact between the neutralizing solution and the acidic gas is improved when decomposing the chlorofluorocarbon gas, which is an environmental pollutant, organic compounds and other hardly decomposable substances such as industrial waste. The present invention can provide a method and an apparatus for neutralizing an acidic gas which does not require a pump for circulating a Japanese liquid and does not cause clogging or corrosion in piping.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a first embodiment of the present invention.

FIG. 2 is a left sectional view of FIG.

FIG. 3 is a plan sectional view showing a second embodiment of the present invention.

FIG. 4 is a front sectional view of FIG. 3;

FIG. 5 is a right side sectional view of FIG. 3;

FIG. 6 is a front sectional view showing a third embodiment of the present invention.

FIG. 7 is a diagram of a CFC treatment system according to the prior application of the present invention.

FIG. 8 is a front sectional view showing another specific example of the conventional neutralization cooler.

FIG. 9 is a side sectional view of FIG. 8;

FIG. 10 is a schematic diagram showing a conventional method for bubbling an acidic gas.

[Explanation of symbols]

41, 42, 43 ... gas washing tower 44 ... neutralization cooler 47, 48, 49, 47b, 48b, 49b, 50b,
63, 64, 65 ... outlet pipes 47a, 48a, 49a, 66a ... nozzles 50, 51, 52, 56, 57, 58, 59, 66 ... air introduction pipe 55 ... gas cleaning section 62 ... pipe 62a ... small hole 67 ... Drainage outlet reference number P3104

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B01D 53/70 F-term (Reference) 4D002 AA17 AA22 AB01 AC10 BA02 CA01 DA02 DA05 DA12 4D020 AA10 BA01 BA08 BB03 CB01 CB25 CB31 CC01 CC05

Claims (9)

[Claims] An acid gas is introduced into one or a plurality of gas washing towers whose lower ends are inserted into a neutralization cooler, and a liquefied component of the acid gas flows from the gas washing tower into the neutralization cooler. Neutralizing and cooling, and by blowing out high-pressure air from the air introduction pipe inserted into the gas cleaning tower, the negative pressure caused by the high-pressure air sucks the neutralization liquid through the outlet pipe to form a mist. A method for neutralizing an acid gas, comprising spraying the gas in a gas washing tower to cool an acid gas component to promote liquefaction. 2. Oxygen or only oxygen and water or water as a solvent is supplied together with the substance to be decomposed and passes through a normal pressure reactor heated to a predetermined temperature for a predetermined reaction time. Oxidative degradation, hydrolytic degradation,
In a method for neutralizing an acid gas that decomposes a hardly decomposable substance based on any one of three decomposition principles of hydrolysis or a combination thereof, an acid gas in a substance to be decomposed is placed in a neutralization cooler at a lower end. The liquefied component of the acidic gas flows into the neutralization cooler from the gas cleaning tower to be neutralized and cooled, and the air inserted from above the gas cleaning tower is introduced into one or more gas cleaning towers inserted through the gas cleaning tower. By jetting high-pressure air from the lower end of the inlet pipe, the negative pressure caused by the high-pressure air sucks the neutralizing liquid through the outlet pipe and sprays it into the gas cleaning tower in the form of a mist from the tip of the nozzle. A method for neutralizing an acidic gas, comprising promoting the liquefaction of an acidic gas component. 3. An acid gas flows through one or a plurality of gas washing towers, the lower end of which is inserted into the neutralizing cooler, and the acidic gas is exhausted to the outside from an exhaust port. The high-pressure air introduction pipe is located close to the top opening of the high-pressure air introduction pipe, and the neutralization liquid is sucked by the high-pressure air and atomized by the high-pressure air to form a gas. An acid gas neutralizing device characterized by promoting liquefaction of an acid gas component by spraying the acid gas into a washing tower. 4. An inflow port for an acidic gas is provided in one or more gas cleaning towers whose lower end is inserted into the neutralization cooler, and the acidic gas flows through the gas cleaning tower via a pipe. While discharging from the exhaust port to the outside, a discharge pipe for neutralizing liquid is extended upward from the inside of the neutralization cooler along the gas cleaning tower, and the tip of a nozzle connected to the upper end of the discharge pipe Part was inserted inside the gas washing tower, and the lower end of the high-pressure air introduction pipe inserted from above the gas washing tower was arranged close to the tip of the nozzle. An acid gas neutralizing device characterized in that it is sucked and atomized from the tip of a nozzle and sprayed into a gas washing tower to promote liquefaction of an acid gas component. 5. A neutralizing cooler and a gas cleaning unit are integrated with each other, an outlet pipe for a neutralizing solution extends from the inside of the neutralizing cooler to the gas cleaning unit, and from a side of the gas cleaning unit. An acid gas neutralizing device, wherein a high-pressure air introduction pipe is inserted in a horizontal direction, and a tip end of the air introduction pipe is arranged close to an upper end of a neutralization liquid outlet pipe. 6. The acid gas neutralizing device according to claim 5, wherein the acid gas is set so as to bypass and flow in the gas cleaning section. 7. A pipe through which an acidic gas flows at a position slightly away from the surface of the neutralizing liquid inside the neutralizing cooler, and is opened through the pipe from inside the neutralizing cooler. An outlet pipe for the neutralizing liquid is extended toward the small hole, and an air inlet pipe is inserted horizontally from the side, and the nozzle of the air inlet pipe is connected to the upper end of the outlet pipe for the neutralizing liquid and the pipe. An acid gas neutralizing device, which is arranged close to a small hole. 8. The acid gas neutralizing device according to claim 7, wherein a drain port for returning a liquid component to a neutralizing liquid is provided at one end of the pipe. 9. A stirring blade driven by a stirrer is provided in the neutralizing cooler.
9. The acid gas neutralizing device according to 5, 6, 7, or 8.