JP2002121154A - Device for decomposing organohalogen compound and method for decomposing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable device for decomposing an organohalogen compound, which can prevent the generation of scales in a steam generator and a reaction pipe, and to provide a method for decomposing the organic halogen compound. SOLUTION: This device for decomposing the organohalogen compound, characterized by disposing a means (water-demineralizing device 27) for removing scale generation-causing elements contained in water supplied into a steam generator 18 on the upstream side of the steam generator 18.

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 an organic halogen compound and a method for decomposing the same.

[0002]

2. Description of the Related Art Organic halogen compounds such as chlorofluorocarbon (so-called chlorofluorocarbon), trichloromethane, and halon 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. It plays a significant role in the industrial field. However, these compounds are highly volatile and remain untreated in air, soil,
If released to the environment such as water, it may cause adverse effects on the environment, such as the generation of carcinogens and the destruction of the ozone layer.
It is necessary to perform detoxification treatment from the viewpoint of environmental conservation.

[0003] Conventionally, there have been reported methods for treating organic halogen compounds, which mainly utilize a 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, an organic halogen compound is incinerated in a cement kiln, rotary kiln, etc., whereas in the plasma method, an organic halogen compound is reacted with water vapor in plasma to decompose it into carbon dioxide, hydrogen chloride, and hydrogen fluoride. Is what you do.

[0004] Further, as for the latter method of controlling the operation of an organic halogen compound decomposing apparatus 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 a reaction tube disposed in a state of being immersed in an alkaline solution in an exhaust gas treatment tank containing an alkaline solution, and a reaction tube whose lower end portion penetrates the upper portion of the reaction tube. It comprises a discharge tube that communicates, a gas supply tube that connects one to the discharge tube and the other to a mixer, a steam generator and the like connected to the mixer.
In addition, in order to generate plasma and decompose the organic halogen compound, a cylindrical waveguide extending vertically above the reaction tube, and disposed inside the cylindrical waveguide and penetrating the lower end thereof. A discharge tube communicating with the reaction tube, a rectangular waveguide extending in the horizontal direction and connected to the cylindrical waveguide near one end thereof, a microwave oscillator mounted on the other end of the rectangular waveguide, etc. It has.

In this decomposition apparatus, the organic halogen compound to be decomposed is heated by a steam generator, and at the same time, water supplied from a water supply source is heated by the steam generator to be steam. The heated organic halogen compound and steam are mixed by a mixer and guided to a reaction tube. On the other hand, the microwave transmitted from the microwave oscillator is transmitted to the cylindrical waveguide through the rectangular waveguide, and causes a discharge in a microwave electric field formed inside the cylindrical waveguide. Then, the organic halogen compound is decomposed by thermal plasma in the reaction tube. The decomposition reaction produces acidic gases (hydrogen fluoride and hydrogen chloride), which are introduced into an alkaline solution by a suction pipe and neutralized, and the remaining gases including carbon dioxide and the like are exhausted. It is discharged from the duct.

[0006]

In the apparatus for decomposing an organic halogen compound according to the plasma method,
Steam is required to decompose the organic halogen compound. However, ordinary tap water has a calcium component,
When the tap water is used as steam, impurities such as sodium component and magnesium component are contained, and the impurities such as calcium component are hardened in the steam generator or the tube wall of the reaction tube, so-called scale (calcite). Occurs. Then, when scale is generated in the steam generator or the reaction tube, there is a problem in that poor decomposition of the organic halogen compound and poor ignition are caused, which hinders the operation of decomposing the organic halogen compound.

The present invention has been made in view of the above problems, and has a highly reliable organic halogen compound decomposing apparatus capable of preventing scale from being generated in a steam generator or a reaction tube. An object of the present invention is to provide a method for decomposing an organic halogen compound.

[0008]

According to the present invention, there is provided an organic halogen compound decomposing apparatus for heating an organic halogen compound and heating water supplied from a water supply source to generate steam. An organic halogen compound comprising: a mixer for mixing the organic halogen compound and the water vapor heated by a steam generator; and a reaction tube for decomposing the halogen compound mixed with the water vapor by the mixer by a plasma method. Wherein a means for removing scale-causing elements contained in water supplied to the steam generator is provided upstream of the steam generator.

In this apparatus for decomposing an organic halogen compound, water from which elements that cause scale generation (scale generation elements) are removed is supplied into the steam generator. There is no scale in the tube.

Further, in the apparatus for decomposing an organic halogen compound of the present invention, the scale-causing element may be calcium (C
a), sodium (Na), and magnesium (Mg).

The scale-causing elements contained in tap water and the like are calcium (Ca), sodium (Na), magnesium (Mg) and the like. Therefore, in this organic halogen compound decomposing device, water from which calcium (Ca), sodium (Na), magnesium (Mg), etc. has been removed is supplied into the steam generator, so that the steam generator and The scale generated in the reaction tube will be significantly reduced.

Further, in the organic halogen compound decomposing apparatus according to the present invention, the means for removing the scale-causing element is a water softener.

By providing the water softener, calcium (Ca), which is a scale generation element, is captured by the water softener. Therefore, in the organic halogen compound decomposing device, the water from which calcium (Ca) has been removed is supplied into the steam generator, so that the scale generated in the steam generator and the reaction tube is significantly reduced. It will be.

Further, in the organic halogen compound decomposing apparatus according to the present invention, the means for removing the scale-causing element is a pure water device.

By providing a water purifier, calcium (Ca), sodium (Na), magnesium (Mg), etc., which are the above-mentioned scale-causing elements, are captured by the water purifier. Therefore, in this organic halogen compound decomposing device, the water from which the above-mentioned elements have been removed is supplied to the steam generator, so that no scale is generated in the steam generator and the reaction tube. Here, the pure water device removes the scale-causing element by an ion exchange resin.

Further, in the apparatus for decomposing an organic halogen compound according to the present invention, means for detecting the quality of the water treated by the means for removing the scale-causing element is provided upstream of the steam generator. And

In this apparatus for decomposing an organic halogen compound, means for detecting the quality of the treated water by means for removing the scale-generating element is provided. Therefore, the performance of the means for removing the scale-generating element by the water quality is improved. When it is recognized that the temperature has decreased, the means for appropriately removing the scale-causing element is replaced or exchanged.

Further, in the apparatus for decomposing an organic halogen compound according to the present invention, the detecting means detects the electric conductivity of the water.

In this apparatus for decomposing an organic halogen compound, water quality can be easily estimated by detecting electric conductivity. Specifically, if the electric conductivity increases, it is presumed that the scale-causing element is contained in the water.

In the method for decomposing an organic halogen compound according to the present invention, the organic halogen compound is heated, and water supplied from a water supply source is heated to form steam. Mix,
Later, the mixed water vapor and the halogen organic compound are introduced into a reaction tube, and in a method for decomposing an organic halogen compound in which the organic halogen compound is decomposed by a plasma method, water supplied from the water supply source is heated. When the water vapor is used, the scale-generating element contained in the water is removed in advance.

In this method for decomposing an organic halogen compound, water from which scale-causing elements have been removed in advance is supplied into the steam generator, so that scale is not generated in the steam generator and the reaction tube. Absent.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS 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 horizontally extending rectangular waveguide 1 has a microwave oscillator 2 for transmitting a microwave having a frequency of 2.45 GHz at a start end thereof, and transmits microwaves from the start end to the end end. .

As shown in FIG. 1, the rectangular waveguide 1 prevents the reflected wave from affecting the oscillation side by absorbing the microwave reflected at the terminal end and returning to the start 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.

The operation of generating a microwave will now 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.

An example of the primary component TE10 is indicated by an arrow whose direction alternates in the propagation direction of the rectangular waveguide in FIG. Further, an electromagnetic wave propagating through the waveguide 1 is provided in the annular cavity of the double cylindrical waveguide formed of a double cylindrical conductor at the other end of the rectangular waveguide 1.
Due to the coupling effect of the conductor 9 of the electromagnetic wave reflected at the pipe end,
A TM wave having an electric field component in the traveling direction is generated in the annular cavity. The TM10 wave as the primary component is also indicated by an arrow in the annular cavity in 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 fundamental damage to the microwave transmitter 2.

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

On the other hand, the distal end of the outer tube 12 penetrates through the end plate 8A of the outer conductor 8 and communicates with the reaction tube 15;
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
There is provided an optical sensor 17 directed to the outer cylinder 12 exposed between the reaction tube 15 and the reaction tube 15. 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 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. 1, the steam is selectively sent from each supply source to the steam generator 18.

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 stored by the plunger pump 25 in a water storage tank 26 (water supply source).
The water inside is sent to the steam generator 18 and the steam generator 1
8 generated. Here, between the plunger pump 25 and the steam generator 18, a pure water generator 27 for removing scale-causing elements contained in water sent from the water storage tank 26 to the steam generator 18 and a downstream side thereof Purifier 2
And a sensor 28 (means for detecting the quality of the water treated by the means for removing the scale-causing element). Further, the water storage tank 26 is provided with a level switch 29 for detecting a change in water level.

The Freon gas is stored in a liquid in a collected Freon cylinder 30, and the collected Freon cylinder 30 and the solenoid 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 chlorofluorocarbon gas, and is of a collision type or a centrifugal type. The steam generator 18 not only generates the above-described water vapor to be reacted with the chlorofluorocarbon gas, but also avoids a disadvantage that the chlorofluorocarbon gas or the like is heated in advance to cool the water vapor to the fluorocarbon gas and recondensate in the apparatus. This is also intended, and a heating system such as an electric system or a steam system is employed.

In the steam generator 18, two parallel flow paths 34a and 34b are formed.
, A Freon gas, an Argon gas, and air are introduced, and water from which a scale generation element has been removed by the pure water device 27 is introduced into the other flow path 34b to generate steam. A resistor 35 that gives resistance to the water vapor moving in the flow path 34b is provided in the flow path 34b that generates the water vapor.
Is filled, so that steam 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. Note that a thermocouple 36 is provided near the outlet of the steam generator 18.

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

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 suction 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 collected from a waste refrigerator, the 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

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 such that the blade 52b is located above the tip of the suction pipe 45, and the bubbles floating from the tip of the suction 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. The bubble separating means 52 maintains an 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 downstream of the discharge 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 and water vapor, first, the operation of the decomposition apparatus is started by supplying heated air for the purpose of removing water 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 scavenging gas is supplied for a predetermined time (5 seconds) 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 stirred 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 stopping 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,
If the state of ignition is stabilized, it is not necessary to continue to 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 is provided with the pressure switch 2
By receiving signals from various sensors such as 3, 33, sensors 28, thermocouples 36 and 54, level switch 29, and optical sensor 17, the supply pressure of argon gas and chlorofluorocarbon gas to the heater 18, the liquid in the water storage tank 26, The temperature, the generation state of the plasma, and the temperature in the exhaust gas treatment tank 41 are constantly monitored. If the values deviate from the specified values, the operation may not be performed normally or efficiently. Stop. 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 heated to 100 to 180 ° C. by passing through the steam generator 18. For this reason, residual moisture in the device is reliably removed, and ignition stability is improved.

Then, the solenoid valve 19c is closed and the solenoid valve 19a is opened to supply argon gas 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.
1 / 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 oscillator 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 intensity is formed, and the electric field mode in the rectangular waveguide 1 and the electric field mode in the rectangular 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. Naturally, the magnetic field is generated in a direction orthogonal to the electric field. 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, water is sucked from a water storage tank 26 by a plunger pump 25 and passed through a pure water device 27 to remove scale-generating elements. 5 Here, the scale-causing element includes a calcium component, a sodium component, a magnesium component and the like contained in water. The pure water device 27 removes scale-causing elements in water using an ion exchange resin.
Further, since the amount of the scale-causing element that can be captured by the pure water device 27 is determined, the scale-causing element is exchanged / replaced according to the usage time, the amount of the scale-causing element contained in the water, and the like. Accordingly, the scale-causing element such as the calcium component contained in the water supplied from the water storage tank 26 is
7, the inside of the steam generator 18 and the reaction tube 1
It is possible to prevent scale, which is a lump of impurities such as calcium components, from being generated on the tube wall of No. 5.

A sensor 28 is provided between the pure water device 27 and the steam generator 18 to detect the electric conductivity of the water passing through the pure water device 27. In other words, by detecting the electric conductivity of water, the amount of scale-causing elements contained in the water can be easily estimated. Specifically, when the electric conductivity increases, the scale-causing elements are included in the water. It contains many elements, which means that the water quality is deteriorating. Therefore, by detecting the electric conductivity of water with the sensor 28, it is possible to immediately detect the deterioration of the performance of the pure water device 27, and it is easy to determine the replacement / replacement time. By exchanging and replacing the pure water device 27 at the best timing, high-quality water can always be led to the steam generator 18.

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.

Further, the steam cannot flow smoothly in the flow path due to the resistor 35 filled in the steam generator 18, and a certain amount of steam always stays in the steam generator 18. It will be in a state of having done 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 30 is discharged 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.

Further, after passing through the steam generator 18,
The water vapor, the argon gas, and the chlorofluorocarbon gas flowing into the inside 7 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 at a predetermined distance inward from the distal end of the probe antenna 9a, it is possible to avoid the thermal influence 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.

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 solution through the suction 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.

Among the generated gas detoxified by the neutralization reaction, gas is exhausted from the exhaust duct 42, and the other gas remains as slurry in the alkaline liquid. In the case where the decomposition operation is stopped, the processing liquid is pumped up by the pump 53a after the air bubble separating means 52 is stopped, and the three-way valve 56 is switched to the sedimentation tank 62.
Transfer to The aggregating agent is uniformly added while stirring the treatment liquid transferred to the settling tank 62 with the stirrer 62a, and the stirrer 62a is stopped to cause precipitation, followed by solid-liquid separation in the dehydrating basket 63,
The liquid is drained and the solid is exhausted. In addition,
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) Although the pure water device removes the scale-generating element using an ion exchange resin, a pure water device that removes the scale-generating element using the principle of distillation may be used.

(2) Although a pure water device is used as a means for removing scale-causing elements, a water softener may be used instead of the pure water device. In this case, the calcium component, which is one of the scale-causing elements, is captured by the water softener. In addition, it is economical because it is cheaper than a pure water device.

(3) Although the sensor is provided separately from the water purifier, a water purifier incorporating a sensor function may be used.
In other words, the electric conductivity of the water treated by the pure water device is detected in the pure water device, and when the electric conductivity becomes equal to or higher than a predetermined value, an alarm may sound or a predetermined lamp may blink. .

(4) As a means for preventing the acid gas from being discharged out of the system due to insufficient neutralization, the motor current value may be managed 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 determined by the distance between the tip of the probe antenna 9a and the energy concentration portion of the microwave unless the inner tube 11 is melted. It is optimal to set them equally, but they may be changed as appropriate in consideration of melting of the inner tube 11.

(7) The bubble dividing means 52 may be a screw type in which a propeller is fixed to the tip of a shaft.

(8) The neutralizing solution stored in the exhaust gas treatment tank 41 is not limited to the above-mentioned alkaline suspension, but may be an alkaline aqueous solution such as an aqueous sodium hydroxide solution.

[0075]

According to the invention as set forth in any one of the first to fourth aspects of the present invention, the water from which the scale-causing element has been removed and the water from which the water has been removed are supplied into the steam generator. Therefore, no scale is generated in the steam generator and the reaction tube, and a highly reliable organic halogen compound decomposer can be realized.

According to the invention described in claim 5 of the present invention,
If it is recognized that the performance of the means for removing scale-causing elements has been reduced by detecting water quality,
Since the means for removing the scale-causing element can be appropriately exchanged or exchanged, water from which the scale-causing element has been removed can always be supplied for steam generation, and a highly reliable organic halogen compound decomposer can be realized.

According to the invention described in claim 6 of the present invention,
By detecting the electric conductivity, the water quality can be easily detected, and a highly reliable organic halogen compound decomposer can be realized.

According to the seventh aspect of the present invention,
Since the water from which the scale-causing elements have been removed in advance is supplied into the steam generator, a highly reliable method for decomposing the organic halogen compound can be realized without generating scale in the steam generator and the reaction tube.

[Brief description of the drawings]

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

FIG. 2 is an enlarged view of a main part of the decomposition apparatus.

FIG. 3 is a perspective view showing an entire configuration of the disassembling 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.

[Explanation of symbols]

15 Reaction Tube 18 Steam Generator 26 Water Storage Tank (Water Supply Source) 27 Pure Water Device 28 Sensor (Means for Detecting Quality of Water Treated by Means for Removing Scale-Causing Element) 37 Mixer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int. Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C02F 5/00 610 C02F 5/00 610C 620 620B 620A C07B 37/06 C07B 37/06 61/00 61/00 D (72) Inventor Masahiro Bessho 1 Takamichi, Iwazuka-cho, Nakamura-ku, Nagoya-shi, Aichi Prefecture Inside Nagoya Research Laboratories, Mitsubishi Heavy Industries, Ltd. F-term (Ref.) 2E191 BA15 BB00 BC01 BD18 4D025 AA02 AA03 AB18 AB19 CA04 4G075 AA03 AA37 AA52 BA01 BA05 BD03 BD12 CA48 CA51 CA55 CA62 DA01 EB21 EB41 4H006 AA04 AA05 AC60 AC95

Claims (7)

[Claims] 1. A steam generator for heating an organic halogen compound and heating water supplied from a water supply source to generate steam, the organic halogen compound and the steam heated by the steam generator. And a reaction tube that decomposes the halogen compound mixed with the water vapor by the mixer by a plasma method. An apparatus for decomposing an organic halogen compound, wherein water supplied to the steam generator is provided. An apparatus for decomposing an organic halogen compound, wherein a means for removing scale-causing elements contained in the steam generator is provided upstream of the steam generator. 2. The scale-causing elements include calcium (Ca), sodium (Na), and magnesium (M).
The apparatus for decomposing an organic halogen compound according to claim 1, wherein the apparatus is at least one selected from g). 3. The apparatus for decomposing an organic halogen compound according to claim 1, wherein the means for removing the scale-causing element is a water softener. 4. The apparatus for decomposing an organic halogen compound according to claim 1, wherein the means for removing the scale-causing element is a pure water device. 5. The steam generator according to claim 1, wherein a means for detecting the quality of the water treated by the means for removing the scale generating element is provided upstream of the steam generator. An apparatus for decomposing an organic halogen compound according to any one of the above. 6. The organic halogen compound decomposing apparatus according to claim 5, wherein said detecting means detects the electric conductivity of said water. 7. An organic halogen compound is heated, and water supplied from a water supply source is heated to form steam, and then the organic halogen compound and the steam are mixed. In the method for decomposing an organic halogen compound, in which the halogen organic compound is guided to a reaction tube and the organic halogen compound is decomposed by a plasma method, when water supplied from the water supply source is heated to be steam, A method for decomposing an organic halogen compound, wherein a scale-causing element contained in water is removed in advance.