JP2001170202A - Decomposition device for organic halogen compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decomposition device for an organic halogen compound which can suppress a cost increase by exchange of a blow pipe. SOLUTION: This decomposition device for the organic halogen compound has a reaction tube which decomposes the organic halogen compound decomposed in the reaction tube, a waste gas treatment tank in which an alkaline solution for neutralizing the decomposed matter decomposed in the reaction tube is housed and the blow pipe 45 which is disposed in the state of immersing its opened bottom end into this alkaline solution and blows the decomposed matter into the alkaline solution from the reaction tube. This blow pipe 45 comprises a tubular blow pipe body section 45a and a front end 45b having an aperture 45c which is disposed at its front end and is opened in the alkaline solution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for decomposing an organic halogen compound such as chlorofluorocarbon.

[0002]

2. Description of the Related Art Organic halogen compounds such as chlorofluorocarbon (so-called chlorofluorocarbon) and trichloromethane containing fluorine, chlorine, bromine and the like in a molecule are widely used in a wide range of applications such as refrigerants, solvents and fire extinguishers. The importance in the industrial field is extremely high. However, these compounds have high volatility, and if released untreated into the atmosphere, soil, water, etc., they may produce carcinogens, destroy the ozone layer, etc.
Since it may adversely affect the environment, it is necessary to perform detoxification treatment from the viewpoint of environmental protection.

[0003] Conventionally, methods for treating organic halogen compounds have been reported which mainly utilize a thermal decomposition reaction at a high temperature, and this treatment method is further roughly classified into an incineration method and a plasma method. In the incineration method, the organic halogen compound is incinerated together with ordinary waste such as resin.On the other hand, in the plasma method, the organic halogen compound is reacted with water vapor in plasma to produce carbon dioxide, hydrogen chloride, and fluorine. It decomposes into hydrogen.

[0004] Further, as for the latter method of controlling the decomposition of an organic halogen compound according to the plasma method, a method of generating plasma using microwaves has recently been developed. The decomposition apparatus used in this decomposition method includes an exhaust gas treatment tank containing an alkaline solution, a reaction tube disposed with the open lower end immersed in the alkaline solution, and a vertically extending above the reaction tube. A cylindrical waveguide, a discharge tube disposed inside the cylindrical waveguide and penetrating the lower end thereof and communicating with the reaction tube, and extending horizontally and connected to the cylindrical waveguide near one end thereof. And a microwave transmitter mounted on the other end of the rectangular waveguide.

[0005] In this decomposition apparatus, while the Freon gas and the water vapor are supplied to the discharge tube, the microwave transmitted from the microwave transmitter is transmitted to the cylindrical waveguide through the rectangular waveguide. Then, a discharge is caused by the microwave electric field formed inside the cylindrical waveguide, and the fluorocarbon gas is decomposed by the thermal plasma in the reaction tube. On the other hand, acid gas (hydrogen fluoride and hydrogen chloride) is generated by this decomposition reaction.
This gas is guided into the alkaline liquid by the blowing pipe and neutralized, and the remaining gas including carbon dioxide gas is discharged from the exhaust duct.

[0006]

In the apparatus for decomposing an organic halogen compound according to the plasma method,
The generated acidic gas (hydrogen fluoride and hydrogen chloride) is blown into the alkaline solution by a blowing pipe, and the acidic gas becomes a strong acidic solution immediately after being dissolved in water and immediately before being neutralized. Since the opening of the blowing pipe is corroded by the acidic liquid, the entire blowing pipe must be replaced, which has caused an increase in cost due to replacement of the blowing pipe.

In view of the above circumstances, an object of the present invention is to provide an apparatus for decomposing an organic halogen compound which can suppress the increase in cost due to replacement of a blowing pipe.

[0008]

Means for Solving the Problems In order to solve the above problems, the present invention employs the following constitution. Claim 1
The organic halogen compound decomposer described in the above, a reaction tube for decomposing the organic halogen compound, an exhaust gas treatment tank containing an alkali solution for neutralizing the decomposition products decomposed in the reaction tube, and an open lower end portion An organic halogen compound decomposing device, which is provided in a state of being immersed in the alkaline liquid and blows the decomposition product from the reaction tube into the alkaline liquid, wherein the blowing pipe has a tubular blowing pipe main body. And a tip provided at the tip of the blow-pipe main body and having an opening that opens in an alkaline liquid, wherein the tip is detachable from the blow-pipe main body. And

In this apparatus for decomposing an organic halogen compound, the blowing pipe comprises a blowing pipe main body and a tip. Therefore, even if the acidic gas generated by the decomposition of the organic halogen compound dissolves in water to form a strongly acidic liquid, thereby corroding the tip, only the tip needs to be replaced. In addition,
Since the degree of corrosion by the acid gas is much smaller than that of the strong acid liquid, there is almost no corrosion of the blow-pipe main body that only allows the passage of the acid gas.

According to a second aspect of the present invention, there is provided an apparatus for decomposing an organic halogen compound according to the first aspect, wherein the distal end has a tapered portion formed on a base end side thereof, The tapered portion is inserted and fitted into the blow pipe main body.

In this apparatus for decomposing an organic halogen compound, the tip is inserted and fitted into the main body of the blow tube at the tapered portion, so that the tip can be attached to the main body of the blow tube.
Easy to remove.

According to a third aspect of the present invention, there is provided an apparatus for decomposing an organic halogen compound according to the first or second aspect, wherein a bubble of a decomposed product blown into the alkaline solution is provided at the tip. It is characterized in that a bubble miniaturization means for miniaturization is provided.

In this apparatus for decomposing an organic halogen compound, air bubbles of a decomposition product are divided by air bubble refining means. When treating gas of the same volume, if the number of bubbles is increased and individual bubbles are reduced, the total surface area is increased and the neutralization reaction with the alkaline liquid is promoted.

[0014]

Next, an apparatus for decomposing an organic halogen compound according to the present invention will be described with reference to FIGS. In FIG. 1, a rectangular waveguide 1 extending in a horizontal direction is provided with a microwave transmitter 2 for transmitting a microwave having a frequency of 2.45 GHz at a starting end thereof, and the microwave is transmitted from a starting end to a terminating end. Transmit.

As shown in FIG. 1, the rectangular waveguide 1 prevents the reflected wave from affecting the transmitting side by absorbing the microwave reflected at the terminal end and returning to the starting end. An isolator 3 and a tuner 6 for moving a plurality of wave adjustment members 4 in and out of the discharge tube 5 so as to adjust the amount of wave mismatch of the wave and converge the wave to the discharge tube 5 are provided.

Here, the operation of generating microwaves will be described. The microwave transmitter 2 is placed at one end of a waveguide having a rectangular cross section, and drives a magnetron to emit an electromagnetic wave having a predetermined frequency. The characteristics of this electromagnetic wave propagation phenomenon can be grasped by solving Maxwell's wave equation relating to the electromagnetic wave. As a result, the electromagnetic wave propagates as an electromagnetic wave TE wave having no electric field component in the propagation direction.

[0017] indicated by arrows the direction examples of the first-order component TE ₁₀ alternates the propagation direction of the rectangular waveguide of Figure 2. The annular cavity of the double-cylindrical waveguide formed of a double-cylindrical conductor at the other end of the rectangular waveguide 1 has conductors 9 for electromagnetic waves propagating in the waveguide 1 and electromagnetic waves reflected at the tube end. , A TM wave having an electric field component in the traveling direction is generated in the annular cavity. The TM ₁₀ wave is the primary component are also shown by the arrows in the annular cavity of FIG. The fine adjustment caused by the second or higher harmonics related to the propagation of the electromagnetic wave is adjusted by the tuner 6. The isolator 3 prevents the microwave transmitter 2 from causing fundamental damage.

As shown in FIG. 2, the discharge tube 5 is composed of an inner tube 11 and an outer tube 12, and is disposed so as to be coaxial with the central axis of the cylindrical waveguide 7. The cylindrical waveguide 7 is composed of an outer conductor 8 and an inner conductor 9 having a smaller diameter than the outer conductor 8, and extends in the vertical direction near the terminal end of the rectangular waveguide 1 while communicating with the rectangular waveguide 1. Connected. The inner conductor 9 surrounds the quartz discharge tube 5 while being fixed to the upper part of the rectangular waveguide 1 and surrounds the outer conductor 8.
, And the extended portion is used as a probe antenna 9a. An ignition electrode 14 connected to an ignition transformer 13 is inserted into the inner tube 11 of the discharge tube 5.

Further, the tip (lower end) of the inner tube 11 is disposed at a predetermined distance inward from the tip of the probe antenna 9a.

On the other hand, the distal end of the outer tube 12 penetrates the end plate 8A of the outer conductor 8 and communicates with the reaction tube 15, and the outer tube 1
The base end side (upper end side) 2 is attached with a gap between the inner conductor 9. End plate 8A of outer conductor 8
An optical sensor 17 is provided between the reaction tube 15 and the outer tube 12 to be exposed. The optical sensor 17 monitors the plasma generation state by detecting the luminous intensity.

In the gap between the inner conductor 9 and the proximal end of the outer cylinder 12, a gas supply pipe 16 is tangentially arranged at the inlet side of the annular passage formed by the outer pipe 12 and the inner pipe 11. Are inserted along. Argon gas (rare gas), Freon gas (organic halogen compound), air, and water vapor are supplied to the annular passage of the discharge tube 5 via the gas supply tube 16. These argon gas, Freon gas and air are
By the opening and closing operations of the solenoid valves 19a, 19b and 19c shown in FIG.

Argon gas is supplied to facilitate ignition prior to generation of plasma, and is stored in an argon cylinder 21. Needless to say, a rare gas such as helium or neon can be used in addition to the argon gas. A pressure regulator 22 and a pressure switch 23 are provided between the argon cylinder 21 and the solenoid valve 19a.
Is provided.

The air is supplied from the air compressor 24 in order to remove moisture remaining in the system to enhance the stability of ignition and to discharge gas remaining in the system. , Nitrogen gas, argon gas and the like are used. The water vapor is necessary for decomposing the chlorofluorocarbon gas, and is generated by sending water in the water storage tank 26 to the heater 18 by the plunger pump 25. This water storage tank 2
6 is provided with a level switch 27 for detecting a change in water level.

The chlorofluorocarbon gas is stored in liquid in a collected chlorofluorocarbon cylinder 28, and the collected chlorofluorocarbon cylinder 28 and the electromagnetic valve 1
9b, the squeezing device 31, the mist separator 3
2, and a pressure switch 33 are provided. The throttle device 31 is provided for quantifying the flow, and is constituted by, for example, a combination of a capillary tube and an orifice.

The mist separator 32 is for removing oil (lubricating oil) and water contained in the CFC gas, and is of a collision type or a centrifugal type. The heater 18 is intended not only to generate water vapor to be reacted with the chlorofluorocarbon gas, but also to prevent the problem that the vapor is cooled down to the chlorofluorocarbon gas and re-condensed in the apparatus by heating the fluorocarbon gas or the like in advance. A heating method such as an electric type or a steam type is adopted.

In the heater 18, two parallel flow paths 3 are provided.
4a and 34b are formed. Freon gas, argon gas, and air are introduced into one flow path 34a, and water is introduced from the water storage tank 26 into the other flow path 34b to generate steam. Channel 3 on the side that generates this water vapor
4b is filled with a resistor 35 that gives resistance to water vapor moving in the flow path 34b, so that the water vapor cannot flow smoothly in the flow path.

As the resistor 35, an inorganic or organic granular, fibrous, porous material or a molded product thereof is employed. From the viewpoint of preventing deterioration at high temperatures, SiO ₂ , Al, and the like are used. ₂ O ₃ , TiO ₂ , MgO, ZrO ₂
And inorganic materials such as oxides, carbides, nitrides and the like. A thermocouple 36 is provided near the outlet of the heater 18.

However, the fluorocarbon gas and the steam that have passed through the heater 18 are mixed in the mixer 37 and then supplied to the discharge tube 5 through the gas supply tube 16.

The reaction tube 15 is provided with a blow-in tube 45 via an exchange joint 44 as shown in FIG. The exchange joint 44 is detachably connected between the reaction tube 15 and the blowing tube 45. FIG. 5 shows an enlarged view of the tip of the blowing pipe 45. The blowing pipe 45 includes a blowing pipe main body 45a and a distal end 45b detachably provided at a distal end thereof. The blow-pipe main body 45a is a circular pipe of about 20φ, and is bent horizontally in the middle. The distal end portion 45b is tubular, one end of which is an opening 45c that opens in the alkaline liquid contained in the exhaust gas treatment tank 41, and the other end of which is a tapered portion 45d. The tip portion 45b is a tapered portion 45
d is inserted and fitted into the blow-pipe main body 45a. Both the blow tube body 45a and the tip 45b are made of SUS
304, SUS316 and the like. If the blow pipe main body 45a and the tip 45b are fixed by welding, the welded portion may be corroded by the alkaline liquid. Therefore, the welding is not performed, and only the insertion fitting is performed.

The exhaust gas treatment tank 41 is provided to neutralize and detoxify acidic gases (hydrogen fluoride and hydrogen chloride) generated when the fluorocarbon gas is decomposed and blown out from the blowing pipe 45. In addition, an alkaline suspension obtained by adding calcium hydroxide to water (hereinafter simply referred to as an alkaline solution) is contained. For example, when the Freon gas to be decomposed is Freon R12 for a refrigerant recovered from a waste refrigerator, the acidic gas generated by the decomposition reaction shown in Formula 1 is rendered harmless by the neutralization reaction shown in Formula 2.

(Formula 1) CCl ₂ F ₂ + 2H ₂ O → 2HCl + 2HF + CO ₂ (Formula 2) 2HCl + Ca (OH) ₂ → CaCl ₂ + 2H ₂ O 2HF + Ca (OH) ₂ → CaF ₂ + 2H ₂ O

Since the neutralized products (calcium chloride and calcium fluoride) produced by the neutralization reaction of the formula (2) have low solubility, some of them are dissolved in an alkaline solution, but most of them are present as a slurry. Further, the carbon dioxide generated by the decomposition reaction of the formula 1 and the acid gas reduced to a very small amount equal to or less than the emission reference value by the neutralization reaction of the formula 2 are connected to the exhaust duct 42 connected above the exhaust gas treatment tank 41. Is discharged out of the system by the blower 43.

From the tip (lower end) of the blowing pipe 45, the gas produced by the decomposition reaction of the formula 1 is released as bubbles into the alkaline solution. Since the larger the contact area with the air and the longer the time until the air bubbles reach the liquid surface, the more the air is promoted, the air bubbles in the exhaust gas treatment tank 41 that accelerate the neutralization reaction of Formula 2 by finely dividing the air bubbles A dividing means 52 is provided.

The bubble dividing means 52 has six blades 52b driven to rotate by a motor 52a. The bubble separating means 52 is arranged such that the blade 52b is located above the tip of the blowing pipe 45, and the bubbles floating from the tip of the blowing pipe 45 hit the blade 52b rotating at about 300 rpm and have a diameter of about 3 mm to 5 mm. Finely divided into bubbles. The bubble separating means 52 also plays a role of forming a suspension of water and water-insoluble calcium hydroxide by stirring the calcium hydroxide powder charged into the exhaust gas treatment tank 41. Bubble separating means 52
Keeps the operating state from the start of the operation of the plasma decomposition apparatus to the end of the operation. Except during the operation of the disassembly unit, it will be stopped.

Further, the exhaust gas treatment tank 41 has a pH value
A sensor 55 is provided. The pH value of the alkaline solution is
The control device 61 (see FIG. 3) constantly monitors the pH value via the pH sensor 55. For example, when the pH value becomes 9 (11 to 12 at the start of operation), the alarm means is activated by a command from the control device 61. At the same time, the disassembly operation is stopped. As the warning means, any means can be used as long as it can draw attention to the surroundings. For example, means such as blinking a lamp or sounding a horn is adopted.

The exhaust gas treatment tank 41 is provided with a cooler 53 for cooling the alkaline liquid because the neutralization reaction of the formula 2 is an exothermic reaction. This cooler 53 is
A pump 53a for taking out the alkaline liquid from the bottom of the exhaust gas treatment tank 41, and a heat radiating section 53c through which the alkaline liquid passes and cooled by a fan 53b are provided. The alkaline liquid cooled by passing through the heat radiating portion 53c is:
It is returned to the exhaust gas treatment tank 41 again. Incidentally, the temperature in the tank is detected by the thermocouple 54.

Further, a three-way valve 56 is provided on the downstream side of the heat radiating section 53c. By switching the three-way valve 56, an alkaline solution containing a slurry as a processing liquid can be sent to the settling tank 62. Has become. A stirrer 62a is provided inside the settling tank 62, and after a coagulant is added to the treatment liquid to cause coagulation, solid-liquid separation is performed by a dehydrating basket 63 provided below the settling tank 62. ing.

The procedure for decomposing chlorofluorocarbon in the organic halogen compound decomposing apparatus having the above structure will be described. The opening and closing operation of the solenoid valve and the ignition operation of the ignition transformer 13 are controlled by the control device 61 as shown in FIG. As is clear from this figure, in this disassembly apparatus, 8
Decomposition of the chlorofluorocarbon gas is performed by batch processing with one cycle of time.

That is, before supplying the chlorofluorocarbon gas or the steam, first, the operation of the decomposition apparatus is started by supplying the heated air for the purpose of removing the moisture remaining in the system for a predetermined time (3 minutes). I do. At this time, the operation of the bubble dividing means 52 also starts at the same time. After the air supply is stopped, the supply of argon gas is started for the purpose of improving ignition stability. Then, during the supply of the argon gas, the microwave is transmitted to ignite the gas by the Tesla coil 14, and the steam and the chlorofluorocarbon gas are supplied to decompose the chlorofluorocarbon. Thereafter, the supply of the argon gas is stopped. The moisture may be removed by drying the air.

After the decomposition operation is stopped, air as a scavenging gas is supplied for a predetermined time (5 hours) for the purpose of ensuring safety.
Min) and purge residual acid gases. The purged acid gas is neutralized in the exhaust gas treatment tank 41. At this time, by keeping the bubble separating means 52 in the operating state, the alkaline liquid is agitated and neutralization is promoted. Thereafter, the purging is stopped and the operation of the decomposition apparatus is terminated. At the same time, the motor 52a is stopped, and the operation of the bubble dividing means 52 is stopped. Since the stirring in the exhaust gas treatment tank 41 is stopped by the stop of the bubble dividing means 52, the slurry precipitates in the tank 41.

In the above steps, the supply of the argon gas and the supply of the chlorofluorocarbon gas may overlap with each other. However, the time between the start of the supply of the chlorofluorocarbon gas and the stop of the supply of the argon gas may be very small. The reason is,
This is because, as long as the ignition state is stabilized, it is not necessary to continuously supply the argon gas, and it is necessary to keep the argon consumption low from the viewpoint of cost reduction. In particular, compared to other plasmas, for example, high frequency induction plasma, plasma by microwave is highly stable,
Even if the supply of the argon gas is stopped, there is almost no effect on the conversion of the chlorofluorocarbon gas into plasma.

The control device 61 includes the pressure switch 2
By receiving signals from various sensors such as 3, 33, thermocouples 36 and 54, the level switch 27, and the optical sensor 17, the supply pressure of argon gas and Freon gas to the heater 18, the liquid level in the water storage tank 26, the plasma Generation state,
The temperature in the exhaust gas treatment tank 41 is constantly monitored, and if these temperatures deviate from the prescribed values, the operation is stopped because there is a possibility that the operation is not performed normally or efficiently. After the operation is stopped, air is supplied as described above to ensure safety, and the residual gas in the device is scavenged.

Next, the chlorofluorocarbon decomposition step shown in FIG. 4 will be described in more detail. First, the solenoid valve 19a,
By closing the solenoid valve 19b and opening the solenoid valve 19c, the air from the air compressor 24 is supplied to the discharge tube 5 via the gas supply tube 16 for three minutes. This air is supplied to the heater 18.
Is heated to 100 to 180 ° C. For this reason, residual moisture in the device is reliably removed,
The ignition stability is improved.

Then, the solenoid valve 19c is closed and the solenoid valve 19a is opened, and argon gas is supplied to the discharge tube 5. At this time, since the argon gas is supplied from the tangential direction of the outer tube 12 and flows down spirally, stagnation is formed near the tip of the inner tube 11 and plasma is easily held.

The gas supply amount at this time is 4 to 40.
l / min, desirably 15 l / min or more. In this setting range, the stagnation is effectively formed, the plasma is more easily held, and the discharge tube 5 is hardly affected by the thermal influence of the plasma, so that melting deformation and breakage thereof are effectively prevented. Become.

Then, a microwave is transmitted from the microwave transmitter 2 at a constant interval from the start of the supply of the argon gas. The microwave is transmitted to the rear end side by the rectangular waveguide 1 and further transmitted to the cylindrical waveguide 7.

At this time, as the electric field in the cylindrical waveguide 7, a TM ₀₁ mode having a large electric field strength is formed, and the electric field mode in the rectangular waveguide 1 and the electric field mode in the cylindrical waveguide 1 are formed by the inner conductor 9. The electric field inside the cylindrical waveguide 7 is stable because the electric field mode inside the cylindrical waveguide 7 is coupled. As a matter of course, the magnetic field is generated in a direction orthogonal to the electrolysis. The gas introduced into the discharge tube 5 is heated to a plasma state by the oscillating electromagnetic field.

Next, a high voltage is applied to the ignition electrode 14 connected to the ignition transformer 13 to generate a spark discharge between the ignition electrode 14 and the inner conductor 9 to ignite. At this time, the interior of the discharge tube 5 is easily ignited because the moisture is removed by air and an easily ignited argon gas is supplied in advance. Next, the water storage tank 2 is moved by the plunger pump 25.
Water is sucked from the heater 6, the water is sucked through the heater 18, and the generated steam is supplied to the discharge tube 5.

After the start of the supply of steam, the supply of the chlorofluorocarbon gas is started as described later. The reason for supplying the steam first is as follows. In the operation control method of the organic halogen compound decomposer according to the present embodiment, the fluorocarbon gas and water vapor are supplied at a constant molar ratio to decompose and react,
Generates acidic gas. This is because if only the fluorocarbon gas is turned into plasma, an unexpected harmful halogen compound is generated due to recombination of the dissociated atoms, so that the detoxification process cannot be performed. Therefore, as described above, by supplying steam to the discharge tube 5 and then supplying chlorofluorocarbon gas, and maintaining the state where water vapor is present at the time of chlorofluorocarbon decomposition,
CFCs can be safely decomposed.

This water vapor cannot flow smoothly in the flow path due to the resistor 35 filled in the heater 18, and a constant amount of water vapor always stays in the heater 18. . For this reason, scattering due to pulsation or bumping is prevented, the outflow amount of steam is stabilized, and fluctuations in the flow rate on the upstream side of the mixer 37 can be effectively suppressed. Therefore, the plasma can be stabilized without causing the disappearance of the plasma, and the processing capability can be improved.

Next, the solenoid valve 19b is opened to supply Freon gas to the discharge tube 5. At this time, the chlorofluorocarbon gas flowing out of the collected chlorofluorocarbon cylinder 28 is supplied to the mist separator 3.
2 to remove oil and moisture.
For this reason, the generation of dirt on pipes and by-products due to lubricating oil in Freon gas is suppressed, and efficient and stable supply of Freon gas and the like can be performed. Does not occur. Therefore, it is possible to stabilize the plasma and improve the processing capability.

The steam, the argon gas, and the chlorofluorocarbon gas that have flowed into the mixer 37 through the heater 18 flow out in a uniformly mixed state, and are supplied to the discharge tube 5. For this reason, the decomposition reaction of Formula 1 is sufficiently performed, and the generation of by-products such as chlorine gas and carbon monoxide can be suppressed.

When the microwave is applied to the Freon gas supplied to the discharge tube 5 in this way, the discharge tube 5
High electron energy and temperature of 2,000K ~
Thermal plasma increased to 6,000 K is generated. At this time, not only the chlorofluorocarbon gas and water vapor but also the discharge tube 5
Since the argon gas is supplied at the same time, the plasma does not disappear.

Further, since the distal end of the inner tube 11 is disposed inside the distal end of the probe antenna 9a by a predetermined distance, the thermal effect of the generated plasma can be avoided.
Melt breakage of the inner tube 11 is prevented. As a result, a stable decomposition operation can be performed without remarkable deformation of the plasma shape.

However, the generation of thermal plasma causes the fluorocarbon gas to be easily dissociated into chlorine, fluorine, and hydrogen atoms, and is easily decomposed by reacting with water vapor as shown in equation 1. When the plasma is stabilized, the electromagnetic valve 19a is closed to stop the supply of the argon gas. Therefore, when the fluorocarbon gas is decomposed for a long time, the supply of argon is unnecessary, and the consumption of argon can be kept low. The gas produced by the decomposition reaction passes through the exchange joint 44 and the blowing pipe 45,
It is released into the alkaline liquid in 1.

Thus, the product gas released into the alkaline liquid through the blowing pipe 45 is rendered harmless by the neutralization reaction of the formula (2). Since the neutralization reaction is an exothermic reaction, the temperature of the alkaline solution is maintained at about 60 ° C. or lower by the cooler 53.

The product gas released as bubbles from the tip of the blowing pipe 45 is supplied to the blade 52 of the bubble dividing means 52.
Since it is finely divided at d, the contact area with the alkaline liquid increases and the time to reach the liquid surface increases, thereby promoting the neutralization reaction. As a result, the amount of acidic gas exceeding the reference value is not discharged out of the system due to insufficient neutralization.

Here, the generated gas (acidic gas) blown out from the tip of the blowing pipe 45 becomes a strongly acidic liquid immediately after being dissolved in water and immediately before being neutralized. For this reason, the tip portion of the blowing pipe 45 is corroded by the strong acidic liquid. As described above, the tip of the blowing pipe 45 is provided with the tip 45b, so that only the tip 45b corrodes, and the blowing pipe main body 45a is prevented from being corroded by the strong acid solution. Tip 4
When the corrosion of 5b has progressed, the tip portion 45b may be removed from the blow-pipe main body portion 45a, and a new tip portion 45b may be fitted. At this time, the tip portion 45b is
Since it is merely inserted into the blow pipe main body 45a at d, it can be easily replaced. Thus, in this example, only the tip 45b needs to be replaced, and
The cost increase due to the entire replacement can be suppressed.

Now, of the product gas detoxified by the neutralization reaction, gas is exhausted from the exhaust duct 42, and the other gas remains as a slurry in the alkaline liquid. After the decomposition operation is stopped, the processing liquid is pumped up by the pump 53a after stopping the bubble separating means 52, and the three-way valve 56 is switched to be transferred to the settling tank 62. The processing liquid transferred to the sedimentation tank 62 is
After the coagulant is uniformly added while stirring at a, the stirrer 62a is stopped to cause sedimentation, and then solid-liquid separation is performed in the dehydrating basket 63.
After the decomposition operation is stopped, the air compressor 24 is driven to scavenge the acid gas remaining in the apparatus, so that the safety is also improved.

The apparatus for decomposing an organic halogen compound according to the present invention is not limited to the above embodiment, but includes the following embodiments.

(1) Injection tube main body 45a and tip 4
5b is made of a SUS material, but may be any material that is resistant to corrosion, such as a titanium alloy. Further, it may be an inorganic substance such as ceramic. (2) In this example, since the replaceable tip 45b is attached to the tip of the blow-pipe main body 45a, the tip 45b can be easily replaced with a different shape. For example, as shown in FIG. 6, a tip portion 45b 'may be used to reduce bubbles of the generated gas blown out from the blowing pipe 45. The distal end portion 45b 'is provided with a large number of exhaust holes 45e (bubble miniaturization means) on the peripheral wall as openings. Thereby, fine air bubbles are blown out from each exhaust port 45c, so that the neutralization reaction of the acid gas is promoted.
Although not shown, the opening 45c may be formed in a mesh shape at the distal end portion 45b in FIG. 5 to reduce the size of the bubbles. Furthermore, a porous body (bubble refining means) may be provided inside the distal end portion 45b to make the bubbles blown out from the opening 45c fine. (3) The means for fixing the blow-pipe main body 45a and the blow-pipe tip 45b is not limited to the insertion fitting.
a, thread grooves may be formed on the inside and outside of the tip portion 45b, respectively, and the tip portion 45b may be screwed to the blow-pipe main body 45a. Alternatively, flanges may be provided on both sides, and the flanges may be screwed to each other in a state where the flanges are attached to each other.

(4) As a means for preventing the acid gas from being discharged out of the system due to insufficient neutralization treatment, the motor current value may be controlled instead of the pH control of the alkaline solution. That is, when the motor speed decreases or stops,
In some cases, the bubbles released from the blowing pipe 45 are not sufficiently divided, and the neutralization reaction is not sufficiently performed. Therefore, the abnormality of the motor rotation is detected based on the motor current value, and the control device 6
If the operation of the decomposer is stopped in accordance with the command from 1, it is possible to prevent the acid gas from being discharged outside the system.

(5) Instead of disposing the tip of the ignition electrode 14 inside the discharge tube 5, it may be arranged outside the discharge tube 5 to ignite by spark discharge. (6) The distance at which the tip of the inner tube 11 separates inward from the tip of the probe antenna 9a is set to be equal to the distance between the tip of the probe antenna 9a and the energy concentration portion due to microwaves unless the inner tube 11 is melted. Is best,
It may be appropriately changed in consideration of the melting of the inner tube 11.

(7) The bubble dividing means 52 may be of a screw type in which a propeller is fixed to the tip of the shaft. (8) The neutralizing solution stored in the exhaust gas treatment tank 41 is not limited to the above-mentioned alkaline suspension, and an alkaline aqueous solution such as a sodium hydroxide aqueous solution may be used.

[0065]

As is clear from the above description, according to the apparatus for decomposing an organic halogen compound of the present invention, only the corroded tip needs to be replaced, so that the entire blowing pipe does not need to be replaced and the cost is reduced. Can be suppressed. Also, since the blow pipe is provided with a tapered portion, it can be easily attached to and removed from the blow pipe main body. Furthermore, since the air bubble miniaturization means is provided at the tip, neutralization of the decomposition product is promoted.

[Brief description of the drawings]

FIG. 1 is a system diagram showing an embodiment of an organic halogen compound decomposing apparatus according to the present invention.

FIG. 2 is a perspective view showing an entire configuration of the disassembling apparatus.

FIG. 3 is an enlarged view of a main part of the decomposition apparatus.

FIG. 4 is a comparison diagram showing the time when microwaves, argon gas and the like are supplied and the time of ignition in the decomposition apparatus over time.

FIG. 5 is an enlarged view showing a tip portion of a blowing pipe in the disassembling apparatus.

FIG. 6 is an enlarged view showing another example of the blowing pipe.

[Explanation of symbols]

 15 Reaction pipe 41 Exhaust gas treatment tank 45 Blowing pipe 45a Blowing pipe main body 45b Tip 45c Opening 45d Taper 45e Exhaust hole (bubble miniaturization means)

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kazuhiro Suzuki 3-1-1 Asahimachi, Nishibiwajima-cho, Nishi-Kasugai-gun, Aichi Prefecture Mitsubishi Heavy Industries, Ltd. Air Conditioning Works F-term (reference) 2E191 BA12 BD11 BD18 4D002 AA21 AB03 AC10 BA02 BA12 CA13 DA70

Claims (3)

[Claims] 1. A reaction tube for decomposing an organic halogen compound, an exhaust gas treatment tank containing an alkali solution for neutralizing decomposition products decomposed in the reaction tube, and an open lower end portion immersed in the alkali solution. An apparatus for decomposing an organic halogen compound, which is provided in a state, and has a blowing pipe for blowing the decomposition product from the reaction tube into the alkaline solution, wherein the blowing pipe has a tubular blowing pipe main body, and the blowing pipe main body. A tip having an opening provided in the alkaline liquid, provided at the tip of the portion, wherein the tip is detachably attached to the blow-pipe main body. Disassembly device. 2. The apparatus for decomposing an organic halogen compound according to claim 1, wherein the distal end portion has a tapered portion formed on a base end side thereof, and the tapered portion is inserted into the blow-pipe main body portion. An organic halogen compound decomposer characterized by being fitted. 3. An apparatus for decomposing an organic halogen compound according to claim 1, wherein said tip portion is provided with a bubble-reducing means for refining bubbles of a decomposition product blown into said alkaline solution. An apparatus for decomposing an organic halogen compound.