JP2002119845A - Apparatus for decomposing organic halogen compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To safely decompose an organic halogen compound by preventing the abnormal operation due to the clogging of a suction pipe or the leakage in a flow passage. SOLUTION: The apparatus for decomposing the organic halogen compound, which is provided with a reactor 15 for decomposing the organic halogen compound and a waste gas treating tank 41 for neutralizing an acidic gas generated by the decomposition in the reactor 15, is equipped with a compressor 46 for sending air to the reactor 15 through an air pipe line 48, a pressure sensor 49 in the pipe line 48, and a controller for controlling the operation of the apparatus and the out put of alarm by detecting the pressure in the reactor 15 based on the detected data from the pressure sensor 49 and comparing the pressure of the reactor 15 with a 1st, 2nd and 3rd prescribed pressures which are previously set.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[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 in a state where an open lower end blowing pipe is immersed in the alkaline solution, and a vertical reactor above the reaction tube. A cylindrical waveguide extending in the horizontal direction, a discharge tube disposed inside the cylindrical waveguide and penetrating the lower end thereof and communicating with the reaction tube, and a cylindrical waveguide extending in the horizontal direction and near one end thereof. It comprises a rectangular waveguide connected to a tube, a microwave transmitter mounted on the other end of the rectangular waveguide, and the like.

[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]

By the way, the hot acid gas and the alkaline solution come into contact with each other at the tip of the blowing pipe for blowing the acidic gas into the alkaline solution, and the neutralized product may solidify and adhere. . If the decomposition treatment is continued for a long time in this state, the blowing pipe is closed and the pressure in the reaction pipe increases, which may cause abnormal operation.

[0007] Leakage in a reaction tube or a flow path for feeding various fluids into the reaction tube may also cause abnormal operation.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a method for decomposing an organic halogen compound capable of safely operating by reliably preventing abnormal operation due to clogging in a blowing pipe or leakage in a fluid path. It is intended to provide a device.

[0009]

In order to solve the above-mentioned problems, an apparatus for decomposing an organic halogen compound according to claim 1 generates thermal plasma by applying energy to a gas containing an organic halogen compound by microwaves. Reacting with water vapor in the thermal plasma in the reaction tube to decompose the organic halogen compound, and the generated gas generated by the decomposition reaction between the organic halogen compound and the water vapor is discharged from the blowing tube provided in the reaction tube into alkali. An organic halogen compound decomposing device that performs a neutralization reaction with the alkali solution by blowing into the liquid, wherein the pressure detecting means detects the pressure in the reaction tube, and the decomposition is performed based on detection data from the pressure detecting means. Control means for controlling the processing operation.

As described above, since the control means controls the decomposition processing operation based on the data detected by the pressure detecting means for detecting the pressure in the reaction tube, for example, the gas is supplied to the reaction tube and the flow path connected thereto. Leaks,
Alternatively, in the case where the pressure in the reaction tube is extremely low or high due to clogging of the blowing tube or the like, the decomposition operation can be prohibited to ensure the safety of the apparatus.

According to a second aspect of the present invention, in the organic halogen compound decomposing apparatus according to the first aspect of the present invention, the control means may be arranged such that the pressure in the reaction tube is lower than a first predetermined pressure. In some cases, it is determined that there is a gas leak in the reaction tube and a flow path connected thereto,
Disintegration processing operation is prohibited.

That is, when the pressure in the reaction tube is lower than the first predetermined pressure, it is determined that there is a gas leak in the reaction tube and the flow path connected thereto, and the decomposition operation is prohibited. Therefore, the safety of the device can be ensured.

According to a third aspect of the present invention, in the organic halogen compound decomposing apparatus according to the second aspect, the control means determines that the pressure in the reaction tube is lower than the first predetermined pressure. It is characterized by outputting an alarm to notify the driver of gas leakage.

That is, when the pressure in the reaction tube is lower than the first predetermined pressure, it is determined that there is gas leakage in the reaction tube and the flow path connected thereto, and an alarm is output. , The driver can be notified, and higher safety can be ensured.

According to a fourth aspect of the present invention, in the organic halogen compound decomposing apparatus according to any one of the first to third aspects, the control means controls the pressure of the reaction tube to be preset. When the pressure exceeds a second predetermined pressure, it is determined that solidified matter has adhered to the blowing pipe, and an alarm is output to notify the driver of the determination.

That is, when the pressure in the reaction tube exceeds a second predetermined pressure set in advance, it is determined that solidified matter has adhered to the blowing tube, and an alarm is output to notify the driver. Cleaning can be encouraged.

According to a fifth aspect of the present invention, in the organic halogen compound decomposing apparatus according to any one of the first to fourth aspects, the control means controls the pressure of the reaction tube to be preset. When the pressure exceeds a third predetermined pressure, it is determined that solidified matter adheres to the blow-in pipe and the blow-in pipe is closed, and the decomposition operation is prohibited.

As described above, when the pressure in the reaction tube exceeds the third predetermined pressure set in advance, it is determined that the blow-in tube is closed by the solidified matter in the blow-in tube, and the decomposition process operation is performed. , The safety of the apparatus can be ensured.

According to a sixth aspect of the present invention, there is provided the organic halogen compound decomposing apparatus according to any one of the first to fifth aspects, wherein the pipe connected to the reaction tube and the pipe are connected via the pipe. Oxygen supply means for feeding oxygen to the reaction tube, wherein the pressure detection means is provided in the pipe and detects the pressure in the reaction pipe via the pipe.

That is, the pressure in the reaction tube can be reliably and accurately detected by the pressure detection means from the pipe connected to the reaction tube in order to supply oxygen into the reaction tube by the oxygen supply means.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an organic halogen compound decomposing apparatus 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 plasma discharge tube 5 by adjusting the amount of wave mismatching of the wave by converging the wave.

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 to drive a magnetron to emit an electromagnetic wave of 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.

[0024] 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 arranged 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 tip of the outer tube 12 penetrates the end plate 8A of the outer conductor 8 and communicates with the reaction tube 15 made of copper.
The proximal end (upper end) of the outer tube 12 is attached with a gap between the outer tube 12 and the inner conductor 9. An optical sensor 17 is provided between the end plate 8A of the outer conductor 8 and the reaction tube 15 toward the exposed outer cylinder 12. The optical sensor 17
The state of plasma generation is monitored 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 provided in the tangential direction 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.

The argon gas is supplied to facilitate ignition prior to generation of plasma, and is stored in the 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 water remaining in the system to enhance ignition stability 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 Freon gas is stored in liquid in a collected Freon cylinder 28, and the collected Freon cylinder 28 and the solenoid valve 1 are stored.
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 chlorofluorocarbon 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 water 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 like having passed through the heater 18 and the water vapor are mixed in the mixer 37 and then supplied to the discharge tube 5 through the gas supply tube 16.

An air compressor 46 is connected to the reaction tube 15 as oxygen supply means for supplying air to the inside, and an air pipe 48 for supplying air is connected to a solenoid valve 19d.
Is provided. The supply position of the air to the reaction tube 15 is as follows:
As shown in FIG. 2, it is provided near the end of the plasma discharge tube 5.

The air pipe 48 is provided with a solenoid valve 19.
A pressure sensor (pressure detecting means) closer to the reaction tube 15 than d.
49 is provided, and the pressure sensor 49
The pressure in the reaction tube 15 is detected via the air pipe 48. The detection signal from the pressure sensor 49 is transmitted to the control device 61.

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 blow-in tube 45. The blow-in tube 45 is made of a SUS material, and is provided in the exhaust gas treatment tank 41 as shown in FIG. It is housed and folded on the way.

The exhaust gas treatment tank 41 is provided to neutralize and render harmless acidic gases (hydrogen fluoride and hydrogen chloride) generated as a result of decomposing the chlorofluorocarbon gas and blown out from the blowing pipe 45. It contains an alkaline suspension of water and calcium hydroxide (hereinafter simply referred to as an alkaline solution). For example,
When the Freon gas to be decomposed is Freon R12 for refrigerant collected from a waste refrigerator, the acid gas as a decomposed product generated by the decomposition reaction shown in Formula 1 is detoxified 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

The neutralized products (calcium chloride and calcium fluoride) produced by the neutralization reaction of the formula (2) have a low solubility, so that a part of them is 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 so 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
A control device (control means) is always provided via the pH sensor 55.
61 (see FIG. 3), for example, when the pH value becomes 9 (11 to 12 at the start of operation), the controller 6
The alarm means is actuated by the command from 1 and the disassembling operation is stopped. Any means can be used as the alarm means, as long as it can draw attention to the surroundings,
For example, means such as blinking a lamp or sounding a horn is employed.

The exhaust gas treatment tank 41 is provided with a cooler 53 for cooling the alkaline liquid (treatment liquid) because the neutralization reaction of the formula 2 is an exothermic reaction. In the following, the treatment liquid refers to an alkaline liquid or a liquid after the alkaline liquid is neutralized, and includes a slurry. The cooler 53 includes a slurry pump (pump) 53a for sucking up the processing liquid, a strainer (foreign matter removing means) 53d for removing foreign matter from the sucked up processing liquid, and a slurry pump 5
The processing liquid sucked up by 3a is discharged into an exhaust gas processing tank 4
A cooling heat exchanger 53c circulating between the cooling water exchanger 1 and an air cooling fan 53b for blowing air to the cooling heat exchanger 53c; and a thermocouple (temperature detecting means) 54 for detecting the temperature of the processing liquid. The control device 61 (see FIG. 3) receives the detection output of the thermocouple 54 and controls the air cooling fan 53b and the slurry pump 53a based on the detection output.

A three-way valve 56 is interposed in the treatment liquid circulation path, and a settling tank (drainage treatment device) 62 from which the treatment liquid branches off from the three-way valve 56 is provided. Three-way valve 56
By switching the processing liquid, the processing liquid
1 and the sedimentation tank 62.
The flow path of the processing liquid is made of heat-resistant vinyl chloride, and a general Y strainer can be used as the strainer 53d. As the cooling heat exchanger 53c, a fin-tube heat exchanger is used, and a heat exchanger used for an air conditioner or the like can be used.

A stirrer 62 a is provided inside the settling tank 62, and after a coagulant is added to the treatment liquid to cause coagulation, the liquid is separated into solid and liquid by a dehydrating basket 63 provided below the settling tank 62. It has become.

The procedure for decomposing chlorofluorocarbon in the organic halogen compound decomposing apparatus having the above configuration 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 and water vapor, 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 ignition transformer 13, 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 processing liquid is agitated and neutralization is promoted. afterwards,
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. However, when the temperature in the exhaust gas treatment tank 41 is high, the alkali liquid is cooled by the cooler 53 as described later. 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 CFC 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.

Next, 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, microwaves are 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 controlled 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 the steam, the supply of the chlorofluorocarbon gas is started as described later. The reason for supplying the steam first is as follows. In the method for controlling the operation of the organic halogen compound decomposing apparatus according to the present embodiment, a fluorocarbon gas and water vapor are supplied at a fixed molar ratio to decompose and react to generate an 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, by supplying steam to the discharge tube 5 and then supplying the chlorofluorocarbon gas as described above and leaving the water vapor present at the time of chlorofluorocarbon decomposition, fluorocarbon can be safely decomposed.

Further, the 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 and by-products from piping and the like due to the lubricating oil in the CFC gas is suppressed, and an efficient and stable supply of CFC 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 chlorofluorocarbon gas supplied to the discharge tube 5, 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, it is possible to avoid the thermal effect of the generated plasma,
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.

Since the generation of thermal plasma causes the fluorocarbon gas to be easily dissociated into chlorine, fluorine and hydrogen atoms, it reacts with water vapor and is easily decomposed 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.

By the way, since the generation of thermal plasma causes the Freon gas to be easily dissociated into chlorine, fluorine and hydrogen atoms, it reacts with water vapor and is easily decomposed as shown in Formula 1. If the decomposition reaction of the chlorofluorocarbon gas in the reaction tube 15 does not proceed sufficiently, CO (carbon monoxide) gas is generated. Then, when the solenoid valve 19d is opened and air is supplied from the air compressor 46 into the reaction tube 15, the air flows into the reaction tube 15 through the air pipe 48, and reacts (combustes) with the CO gas to generate CO ₂ gas. I do.

The product gas released into the alkaline solution through the blowing pipe 45 is rendered harmless by the neutralization reaction of the formula (2). Since this neutralization reaction is an exothermic reaction, the temperature of the alkaline solution is cooled by the cooler 53. That is, the output of the thermocouple 54 is input to the control device 61, and the control device 61 appropriately drives the slurry pump 53a and the air-cooling fan 53b with an upper limit of about 60 degrees so that the temperature of the alkaline solution does not increase too much. I do. Since the slurry pump 53a and the fan 53b can be stopped until the temperature of the processing liquid rises to about 60 degrees, power consumption is suppressed.

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.

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 disassembly operation is stopped,
After stopping the bubble separating means 52, the three-way valve 56 is switched, and the processing liquid is pumped up by the slurry pump 53a and transferred to the settling tank 62. While the treatment liquid transferred to the settling tank 62 is stirred by the stirrer 62a, the coagulant is uniformly added thereto.
After the 2a is stopped and settled, solid-liquid separation is performed in the dehydrating basket 63, the liquid component is subjected to wastewater treatment, and the solid component is discarded. After the disassembly 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.

Next, the control by the control unit (control means) 61 in the above-mentioned disassembling apparatus will be further described with reference to the flowchart shown in FIG. When the decomposition device is started, first, an operation preparation mode in which air is sent from the air compressor 24 to scavenge the inside of the device is performed, and then, an ignition mode in which ignition is performed by the ignition transformer 13 is performed.
Thereafter, a decomposition mode in which the gas is decomposed while feeding air as combustion air from the compressor 46 into the reaction tube 15 is set. The control device 61 performs the following control based on a detection signal from the pressure sensor 49 provided in the air pipe 48 in the operation preparation mode and the disassembly mode.

Based on the detection signal from the pressure sensor 49, the detected pressure P and a first predetermined pressure P1,
The second predetermined pressure P2 is compared with the third predetermined pressure P3, and control is performed as follows.

Here, the first predetermined pressure P1, the second predetermined pressure P2, and the third predetermined pressure P3 are set as follows. The first predetermined pressure P1 occurs when gas leaks in the reaction tube 15 or a flow path connected to the reaction tube 15 and the internal pressure of the reaction tube 15 does not rise even though air is supplied from the compressor 24 or the compressor 46. Pressure. When the neutralized product is solidified at the end of the blowing pipe 45 and the cross-sectional area of the flow path is reduced, and the air is supplied from the compressor 24 or the compressor 46, the second predetermined pressure P1 Is higher than the normal value, and it is necessary to clean the tip of the blowing pipe 45. The third predetermined pressure P3 is such that when the end of the blowing pipe 45 is blocked by the solidified neutralization product and the air is supplied from the compressor 24 or the compressor 46, the internal pressure in the reaction pipe 15 exceeds the normal value. Further, it is a pressure at which there is a possibility that the disassembling operation may be hindered.

When detecting that the detected pressure P in the reaction tube 15 is lower than the first predetermined pressure P1 (step S1), the control device 61 causes the gas to flow through the reaction tube 15 or a flow path connected to the reaction tube 15. It is determined that a leak has occurred, and a leak alarm is displayed to notify the driver of the leak (step S2), and the operation of the device is stopped.

When detecting that the detected pressure P in the reaction tube 15 is higher than the second predetermined pressure P2 (step S4), the control device 61 solidifies the neutralized product at the tip of the blowing tube 45, It is determined that the cross-sectional area of the flow path has decreased, and that the tip of the blowing pipe 45 needs to be cleaned, and a blocking alarm is displayed to notify the driver of the fact and to prompt the driver to clean (step S5).

Further, the detected pressure P in the reaction tube 15 becomes the third pressure.
Is determined to be higher than the predetermined pressure P3 (step S
6) If it is determined that the pressure is higher than the third predetermined pressure P3,
It is determined that there is a possibility that the blow-pipe 45 is blocked by the neutralized product solidified at the distal end and hinder the decomposition operation, the operation of the apparatus is stopped (step S3), and the third predetermined pressure is set. If it is determined to be P3 or less, the operation of the device is continued (step S7).

In the above control, the detected pressure P is changed to the first pressure.
If the pressure is higher than the predetermined pressure P1 (step S1) and lower than the second predetermined pressure P2 (step S4),
The detected pressure P is within the range of the normal value,
It is determined that there is no blockage, and the operation of the apparatus is performed (step S7).

As described above, according to the decomposing device, the control device 61 controls the decomposing operation based on the data detected by the pressure sensor 49 for detecting the pressure in the reaction tube 15. If the pressure inside the reaction tube 15 is extremely low or high due to leakage of gas in the reaction tube 15 and the flow path connected thereto, or clogging of the blowing tube 45, Processing safety is ensured by prohibiting the processing operation.

That is, when the pressure in the reaction tube 15 is lower than the first predetermined pressure P1, the reaction tube 1
It is determined that there is a gas leak in the flow path 5 and the flow path connected thereto, the disassembly processing operation is prohibited, and an alarm is output to notify the driver, thereby ensuring the safety of the device. it can. In addition, when the pressure in the reaction tube 15 exceeds a second predetermined pressure P2 set in advance, it is determined that solidified matter has adhered to the blow-in tube 45, and an alarm is output to the driver. Can be notified to encourage cleaning.

Further, when the pressure in the reaction tube 15 exceeds a third predetermined pressure P3 set in advance, the blowing tube 45
Since it is determined that the blow-in pipe 45 is closed by the solidified matter adhering to the inside and the disassembling operation is prohibited, the safety of the apparatus can be more reliably ensured. Further, the pressure in the reaction tube 15 can be reliably and accurately detected by the pressure sensor 49 from the air pipe 48 connected to the reaction tube 15 for sending oxygen into the reaction tube 15 by the compressor 46.

In the above-described decomposition apparatus, scavenging / ignition air and combustion air are supplied from the compressors 24 and 46, respectively. However, these are branched from one compressor and supplied respectively. Is also good.

The apparatus for decomposing an organic halogen compound according to the present invention is not limited to the above embodiment.
The following forms are also included. (1) Although the three-way valve 56 is provided downstream of the cooling heat exchanger 53c, it may be provided downstream of the slurry pump 53a and upstream of the cooling heat exchanger 53c. (2) As a means to prevent the acid gas from being discharged outside the system due to insufficient neutralization treatment, instead of controlling the pH of the alkaline solution,
The motor current value may be managed. That is,
When the motor speed decreases or stops, the air bubbles discharged from the blowing pipe 45 may not be sufficiently divided, and the neutralization reaction may not be sufficiently performed. Therefore, if the abnormality of the motor rotation is detected based on the motor current value and the operation of the decomposing device is stopped by a command from the control device 61, the discharge of the acid gas out of the system can be prevented beforehand. (3) 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. (4) The distance at which the distal end of the inner tube 11 is separated inward from the distal end of the probe antenna 9a is set to be equal to the distance between the distal end 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. (5) The bubble dividing means 52 may be of a screw type in which a propeller is fixed to the tip of the shaft. (6) 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 an aqueous sodium hydroxide solution may be used.

[0082]

As described above, according to the organic halogen compound decomposing apparatus of the present invention, the following effects can be obtained. According to the apparatus for decomposing an organic halogen compound according to claim 1, since the control means controls the decomposition treatment operation based on the data detected by the pressure detecting means for detecting the pressure in the reaction tube. If the pressure in the reaction tube is extremely low or high due to leakage of gas in the flow path connected to it, or clogging of the blowing pipe, the decomposition Safety can be ensured.

According to the second aspect of the present invention, when the pressure in the reaction tube is lower than the first predetermined pressure, the gas is passed through the reaction tube and the flow path connected thereto. Since it is determined that there is a leak and the disassembly processing operation is prohibited, the safety of the apparatus can be reliably ensured.

According to the third aspect of the present invention, when the pressure in the reaction tube is lower than the first predetermined pressure, the gas is passed through the reaction tube and the flow path connected thereto. When it is determined that there is a leak, an alarm is output to notify the driver, and higher safety can be ensured.

According to the fourth aspect of the present invention, when the pressure in the reaction tube exceeds the second predetermined pressure, it is determined that the solidified material has adhered to the blow tube. Then, an alarm is output to notify the driver to urge cleaning.

According to the fifth aspect of the present invention, when the pressure in the reaction tube exceeds a third predetermined pressure, the blow tube is blocked by the solidified material attached to the blow tube. Is determined to be performed and the disassembly processing operation is prohibited, so that the safety of the apparatus can be reliably ensured.

According to the apparatus for decomposing an organic halogen compound according to the sixth aspect, the pressure in the reaction tube is reliably and accurately measured by a pressure detection means from a pipe connected to the reaction tube for feeding oxygen into the reaction tube by the oxygen supply means. It can be detected well.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a decomposition apparatus used in an embodiment of a decomposition method 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, etc. are supplied and the time of ignition in the decomposition apparatus over time.

FIG. 5 is a flowchart illustrating a flow of control by a control device of the decomposition apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 15 Reaction tube 45 Blowing tube 46 Compressor (oxygen supply means) 48 Air pipe (pipe) 49 Pressure sensor (pressure detection means) 61 Control device (control means) P1 First predetermined pressure P2 Second predetermined pressure P3 Third Predetermined pressure

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C07B 37/06 B01D 53/34 ZAB C07C 19/04 134E 19/10 134F (72) Inventor Yuji Okada Aichi 3-1-1 Asahimachi, Nishi-Biwajima-cho, Nishi-Kasugai-gun, F-term F-term (Ref.) 4D002 AA21 AC10 BA05 BA06 BA07 BA12 CA06 CA13 CA20 DA05 DA12 DA35 EA02 GA02 GA03 GB04 HA03 4G075 AA03 BA01 BA05 BA06 BB03 BD03 BD12 BD27 CA26 CA47 EB41 4H006 AA05 AC13 AC26 BA95 BB31 BE10 BE11 BE12 BE13 BE60 EA02

Claims (6)

[Claims] 1. A thermal plasma is generated by applying energy to a gas containing an organic halogen compound by microwaves, and is reacted with water vapor in the thermal plasma in a reaction tube to decompose the organic halogen compound. An organic halogen compound decomposing apparatus for performing a neutralization reaction with the alkali solution by blowing a product gas generated by a decomposition reaction between the compound and water vapor from a blowing tube provided in the reaction tube into an alkali solution, An apparatus for decomposing an organic halogen compound, comprising: pressure detecting means for detecting the pressure in the reaction tube; and control means for controlling a decomposition operation based on detection data from the pressure detecting means. 2. The control device according to claim 1, wherein the pressure in the reaction tube is lower than a first predetermined pressure.
2. The organic halogen compound decomposing apparatus according to claim 1, wherein it is determined that there is gas leakage in the reaction tube and a flow path connected to the reaction tube, and the decomposition operation is prohibited. 3. The control device according to claim 2, wherein when the pressure in the reaction tube is lower than the first predetermined pressure, an alarm is output to notify a driver of gas leakage. The organic halogen compound decomposer according to the above. 4. The control means, wherein the pressure of the reaction tube is:
2. The method according to claim 1, wherein when a predetermined second predetermined pressure is exceeded, it is determined that solidified matter has adhered to the blow-in pipe, and an alarm is output to notify the driver of the fact. 4. The organic halogen compound decomposer according to any one of claims 1 to 3. 5. The control means, wherein the pressure of the reaction tube is:
When the pressure exceeds a third predetermined pressure set in advance, it is determined that solidified matter adheres in the blow-in pipe and the blow-in pipe is closed, and the decomposition operation is prohibited. The organic halogen compound decomposer according to any one of claims 1 to 4. 6. A piping connected to the reaction tube, and oxygen supply means for feeding oxygen to the reaction tube through the piping, wherein the pressure detection means is provided in the piping and connects the piping to the reaction tube. The apparatus for decomposing an organic halogen compound according to any one of claims 1 to 5, wherein the pressure in the reaction tube is detected via a pressure sensor.