JP3852645B2 - Ion exchange resin volume reduction processing apparatus and processing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a volume reduction processing apparatus for ion exchange resin generated as waste, and more particularly to a processing apparatus and a processing method for performing ash volume reduction processing using active oxygen generated by discharge in an oxygen-containing atmosphere.
[0002]
[Prior art]
FIG. 6 is a cross-sectional view schematically showing a configuration of an ion exchange resin volume reducing apparatus using a high frequency induction coil filed in Japanese Patent Application No. 9-37478. The volume reduction treatment apparatus includes a reaction vessel 2 containing a ceramic processing dish 4 on which an ion exchange resin 3 to be treated is mounted, a discharge vessel 1 arranged in communication with the reaction vessel 2, and a discharge vessel 1. A high frequency induction coil 9 wound outside, an exhaust pipe 7 incorporating a decompression pump 6 for exhausting the inside of the reaction vessel 2 and the discharge vessel 1, and a plurality of oxygen or oxygen containing oxygen inside the reaction vessel 2 and the discharge vessel 1 It is comprised from the gas inlet 5 for introducing this gas. The reaction vessel 2 is formed using aluminum, which is a metal material that shields high frequencies and is resistant to active oxygen, and the discharge vessel 1 is made of a quartz tube that is an electrically insulating member that is resistant to active oxygen through high frequencies. Is formed.
[0003]
In this configuration, the gas is exhausted by the decompression pump 6, a gas containing oxygen is introduced from the gas introduction port 5 to make the inside of the reaction vessel 2 have a decompressed oxygen-containing atmosphere, and a high-frequency current is supplied from the high-frequency generator 10 to the high-frequency induction coil 9. Then, a high frequency magnetic field is generated inside the discharge vessel 1, and discharge is formed and maintained by the action of electromagnetic induction to generate active oxygen and ions. At this time, the discharge and the high-frequency power of the high-frequency induction coil 9 are inductively coupled, and the induction electric field that crosses in the turning direction generated inside the discharge accelerates the electrons, so that the high-frequency power is supplied inside the discharge. These generated active oxygen and ions are blown out from the open end 8 into the reaction vessel 2 due to volume expansion due to gas flow or temperature rise, and reach the ion exchange resin 3 mounted on the processing dish 4 to act. The ashing volume reduction process proceeds effectively.
[0004]
FIG. 7 is a cross-sectional view schematically showing a different configuration of an ion exchange resin volume reducing apparatus using a high-frequency induction coil, which is also filed in Japanese Patent Application No. 9-37478.
As in the apparatus shown in FIG. 6 described above, the present volume reduction treatment apparatus includes a reaction vessel 2A containing a treatment dish 4 equipped with an ion exchange resin 3, a discharge vessel 1A arranged in communication with the reaction vessel 2A, a discharge vessel A high-frequency induction coil 9A wound outside the container 1A, an exhaust pipe 7 incorporating a reaction container 2A and a decompression pump 6 for exhausting the inside of the discharge container 1A, and oxygen or oxygen in the reaction container 2A and the discharge container 1A 6 is different from the apparatus shown in FIG. 6 in that the discharge vessel 1A and the high-frequency induction coil 9A wound around the discharge vessel 1A have a dome shape. There is in point.
[0005]
Therefore, in this configuration, since the discharge region formed in the discharge vessel 1A has a large spread toward the ion exchange resin 3 placed in the reaction vessel 2A, the area of the ion exchange resin 3 exposed to the active oxygen is small. Therefore, a large amount of ion exchange resin 3 can be effectively reduced in volume.
[0006]
[Problems to be solved by the invention]
The apparatus as described above has excellent characteristics, and is particularly effective for volume reduction treatment of waste ion exchange resin from nuclear facilities. However, these devices still have the following problems.
That is, in these devices, ashing and volume reduction treatment of ion exchange resin is performed by direct oxidation by contact with discharge active species generated by discharge under reduced pressure. The low-melting-point chelating agent contained together as is thermally decomposed by a temperature rise caused by collision of high-temperature particles and radiation from plasma, and easily vaporizes. Therefore, in actual processing, it is necessary to completely oxidize and decompose the pyrolysis vapor in the gas phase. However, in these apparatuses, the pyrolysis vapor gas cannot be sufficiently oxidatively decomposed in the space on the back side, which is a shadow of the flow of the discharge active species, so that incomplete oxides are generated and these are condensed and tar. There is a problem that the apparatus is soiled. Furthermore, when a large amount of pyrolytic vapor is generated, the exhaust gas is exhausted as incomplete oxide without being sufficiently oxidized and decomposed, and these are condensed in the exhaust system to become tar or the like. There is a problem of fouling. For this reason, in these apparatuses, it is often necessary to perform maintenance work, and there is a problem that secondary waste also increases.
[0007]
The object of the present invention is to achieve complete oxidation in the gas phase by effectively contacting the pyrolysis vaporized gas and the discharge active species, or by effectively adjusting the amount of pyrolysis gas generation, and the processing efficiency is high. An object of the present invention is to provide an ion exchange resin volume reduction treatment apparatus and a treatment method that are low in secondary waste such as tar due to incomplete oxides, and therefore can be used easily and efficiently.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention,
A reaction vessel containing a processing tray loaded with an ion exchange resin to be treated; a depressurizing means for depressurizing the reaction vessel; a gas introducing means for introducing oxygen or a plurality of gases containing oxygen into the reaction vessel; Alternatively, a plurality of gases containing oxygen are introduced, discharge is generated by the electromagnetic field effect of the wound high frequency induction coil, and the active oxygen generated by the discharge is applied to the ion exchange resin to be treated from the upper part in the vertical direction to reduce ashing. In the ion exchange resin volume reduction treatment equipment
(1) At least the upper end surface of the exhaust port of the reaction vessel connected to the decompression unit is arranged at a position higher than the upper end of the ion exchange resin to be processed loaded on the processing dish, and further the reaction vessel connected to the gas introduction unit At least the lower end face of the gas inlet is arranged at a position lower than the lower end of the processing dish.
[0009]
(2) In the above (1), the processing tray on which the ion exchange resin to be processed is loaded is further arranged on a moving stage that can move in the vertical direction.
(3) In the above (1) or (2), a flat window made of an electrically insulating material is arranged on the upper surface in the vertical direction of the reaction vessel so as to face the ion exchange resin to be processed loaded on the processing dish. A high-frequency induction coil is installed on the upper part.
[0010]
Furthermore, oxygen or a plurality of gases containing oxygen are introduced into a reaction vessel containing a processing tray loaded with the ion exchange resin to be processed to create an oxygen-containing atmosphere, and discharge is generated by the electromagnetic field action of the wound high-frequency induction coil. In the ion exchange resin volume reduction treatment method, the active oxygen generated by the discharge is caused to act on the ion exchange resin to be treated from the upper part in the vertical direction to reduce the ashing volume.
(4) The treatment dish is moved in the vertical direction within a region having the installation height of the gas inlet of the reaction vessel as the lower end and the installation height of the exhaust port of the reaction vessel as the upper end, and the properties of the ion exchange resin to be treated Accordingly, a method of adjusting the distance between the high-frequency induction coil and the ion exchange resin to be treated and ashing and reducing the volume of the ion exchange resin to be treated is used.
[0011]
With the configuration as described in (1) above, the pyrolysis vapor generated from the ion exchange resin to be treated flows from the lower gas inlet to the upper exhaust port, that is, from the ion exchange resin to the discharge region side. Therefore, there is no risk of thermal decomposition vaporization gas staying on the back side of the ion exchange resin to be treated, which is a shadow of the flow of the discharge active species, and the chance of contact with the active species is increased and effectively oxidized and decomposed. Occurrence of tar and the like due to complete oxide condensation is suppressed, and maintenance is facilitated.
[0012]
Further, when configured as in (2), the distance between the high frequency induction coil and the ion exchange resin to be processed can be adjusted, and the temperature rise of the ion exchange resin to be processed due to plasma heating can be adjusted. The amount of gas generated can be adjusted, and complete oxidation in the gas phase can be realized.
Further, when configured as in (3), the processing space becomes a discharge space and wasteful space is reduced, so that the utilization efficiency of the generated active species for the ion-exchange resin to be processed can be improved, and high-frequency induction is performed. Since the coil is placed in close proximity to the ion exchange resin to be treated through a flat window, the heating effect of the plasma can be used effectively, so the carbon of the ion exchange resin that has undergone thermal decomposition is further reduced by ashing Thus, high volume reduction processing can be realized.
[0013]
In addition, if a method such as (4) is used, the distance between the high frequency induction coil and the ion exchange resin to be treated is adjusted according to the condition of the ion exchange resin to be treated, and the temperature rise of the ion exchange resin to be treated due to plasma heating is increased. Since it becomes possible to adjust, the generation amount of the pyrolysis vaporized gas can be adjusted according to the amount of active species generated, and complete oxidation in the gas phase can be realized.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
<Example 1>
FIG. 1 is a cross-sectional view schematically showing a basic configuration of a first embodiment of the ion exchange resin volume reduction treatment apparatus of the present invention. This volume reduction processing apparatus is formed based on the configuration shown in FIG. 7, and the difference from the processing apparatus of FIG. 7 is that the exhaust port 11 of the reaction vessel 2B connected to the decompression pump is a processing dish. The ion-exchange resin 3 loaded on 4 is disposed at a position higher than the upper end, and the gas inlet 5 is provided at a position lower than the lower end of the processing dish 4. In this figure, the exhaust pipe provided with the pressure reducing pump is omitted.
[0015]
With this configuration, the gas introduced from the gas introduction port 5 forms a gas flow that flows upward from the back surface of the processing dish 4 and then toward the exhaust port. Inflow of pyrolysis vaporized gas to the back side of the processing dish 4 that is not exposed is suppressed. Further, since the pyrolysis vapor flows from the ion exchange resin 3 toward the upper discharge region side, the probability of contact with the active species increases. From the above, the contamination caused by the incomplete oxide of the pyrolysis vaporized gas on the back side of the processing dish 4 seen in the conventional apparatus is reduced, and the oxidative decomposition of the pyrolysis vaporized gas in the reaction vessel 2B is reduced. Since the probability increases, secondary waste such as tar due to incomplete oxide is reduced, and exhaust system fouling is reduced. Therefore, the amount of maintenance is reduced and it can be used efficiently.
[0016]
<Example 2>
FIG. 2 is a cross-sectional view schematically showing the basic configuration of the second embodiment of the ion exchange resin volume reduction treatment apparatus of the present invention. This volume reduction treatment apparatus is formed on the basis of the configuration shown in FIG. 6. The difference from the treatment apparatus of FIG. 6 is that a discharge / reaction vessel 12 that integrates a conventional discharge vessel and a reaction vessel is used. In the same manner as in the first embodiment, the exhaust port 11 is disposed on the discharge region exposure side at a position higher than the upper end of the ion exchange resin 3 loaded on the processing dish 4, and the gas introduction port 5 is provided. It exists in the position lower than the lower end of the processing dish 4.
[0017]
By configuring in this way, the gas generated by the ashing volume reduction treatment is surely exhausted through the discharge region, so that it is directly discharged and decomposed in the discharge region and comes into contact with the active species with a higher probability. It will be. For this reason, since the oxidative decomposition ratio of the pyrolysis vaporized gas increases, not only the space adjacent to the lower surface of the processing dish 4 but also the ratio of incomplete oxide in the exhaust system is reduced, resulting in condensation of incomplete oxide. Generation of tar and the like is suppressed.
[0018]
<Example 3>
FIG. 3 is a cross-sectional view showing a basic configuration of a third embodiment of the ion exchange resin volume reducing apparatus according to the present invention. This volume reduction processing apparatus is formed on the basis of the configuration of the first embodiment shown in FIG. 1, and the difference from the first embodiment is that the moving mechanism 21 is incorporated so as to be movable in the vertical direction. The processing tray 4 loaded with the ion exchange resin 3 is placed on the moving stage 22 and the ashing and volume reduction processing is performed.
[0019]
In this structure, the process according to the property of resin to be processed can be performed by adjusting the position of the moving stage 22 in the vertical direction. That is, in the case of a resin that has high temperature resistance and is difficult to be thermally decomposed by heating with plasma, the moving stage 22 is disposed relatively upward, and the ion exchange resin 3 is brought close to the discharge region and actively exposed to active particles. Thus, the generation of incomplete oxide is suppressed by increasing the processing efficiency. Further, in the case of containing a large amount of chelating material or a resin having low temperature resistance, the moving stage 22 is disposed relatively downward to keep the ion exchange resin 3 away from the discharge region to suppress heating by plasma. Therefore, it is possible to suppress the generation of a large amount of pyrolysis gas and to effectively reduce the generation of tar and the like due to the generation of incomplete oxide due to the lack of active species.
[0020]
<Example 4>
FIG. 4 is a cross-sectional view showing the basic configuration of a fourth embodiment of the ion exchange resin volume reducing apparatus according to the present invention. This volume reduction processing apparatus is formed on the basis of the configuration of the second embodiment shown in FIG. 2, and the difference from the second embodiment is incorporated by the moving mechanism 21 so as to be movable in the vertical direction. The processing tray 4 loaded with the ion exchange resin 3 is placed on the moving stage 22 to perform the ashing and volume reduction processing.
[0021]
Therefore, similarly to the third embodiment, the processing can be performed by adjusting the position of the moving stage 22 in accordance with the properties of the resin to be processed, and the generation of tar and the like due to the condensation of incomplete oxide is effectively performed. Can be reduced.
<Example 5>
FIG. 5 is a cross-sectional view showing a basic configuration of a fifth embodiment of the ion exchange resin volume reducing apparatus according to the present invention.
[0022]
This volume reduction treatment apparatus is formed on the basis of the configuration of the third embodiment shown in FIG. 3, and the difference from the third embodiment is the same as that of the reaction container of the third embodiment. A discharge / reaction vessel 12A is configured by arranging a flat plate window 31 made of quartz that is resistant to active oxygen through high frequency on the upper surface of the vessel, and a high frequency induction coil 9C is arranged close to the upper surface of the flat plate window 31. It is in the point.
[0023]
In this configuration, if the processing plate 4 that is normally flat is arranged upward by the moving stage 22, the flat window 31 and the processing plate 4 are arranged to face each other at a short interval, so that the discharge region is expanded. Can be reduced. Therefore, the ion exchange resin 3 is very effectively exposed to the discharge region and is effectively heated by the plasma, so that the carbon component and ash content of the ion exchange resin after the completion of the thermal decomposition can be effectively oxidized. An extremely large volume reduction effect can be obtained.
[0024]
【The invention's effect】
As mentioned above, according to the present invention,
A reaction vessel containing a processing tray loaded with an ion exchange resin to be treated; a depressurizing means for depressurizing the reaction vessel; a gas introducing means for introducing oxygen or a plurality of gases containing oxygen into the reaction vessel; Alternatively, a plurality of gases containing oxygen are introduced, discharge is generated by the electromagnetic field effect of the wound high frequency induction coil, and the active oxygen generated by the discharge is applied to the ion exchange resin to be treated from the upper part in the vertical direction to reduce ashing. In the ion exchange resin volume reduction treatment equipment
(1) At least the upper end surface of the exhaust port of the reaction vessel connected to the decompression unit is arranged at a position higher than the upper end of the ion exchange resin to be processed loaded on the processing dish, and further the reaction vessel connected to the gas introduction unit At least the lower end surface of the gas inlet is arranged at a position lower than the lower end of the processing dish, so that condensation of incomplete oxide on the lower surface side of the processing dish is prevented, and the oxidative decomposition effect in the gas phase Therefore, it is possible to obtain an ion-exchange resin volume reduction treatment device that has high treatment efficiency, little secondary waste such as tar due to incomplete oxides, and therefore can be used easily and efficiently. It became.
[0025]
(2) Further, in (1) above, if the processing tray on which the ion exchange resin to be processed is loaded is arranged on a movable stage that is movable in the vertical direction, a high frequency is provided according to the state of the resin to be processed. The interval between the induction coil and the resin to be treated can be adjusted, and the generation amount of pyrolysis vaporized gas can be adjusted according to the amount of generated discharge active species, and complete oxidation in the gas phase can be realized. It is suitable as an ion exchange resin volume reduction treatment device that can be used easily and efficiently.
[0026]
(3) Further, in the above (1) or (2), a flat window made of an electrically insulating material is disposed on the upper surface in the vertical direction of the reaction container so as to face the ion exchange resin to be processed loaded on the processing dish. However, if a high frequency induction coil is installed on the upper part, the ion exchange resin 3 can be exposed to the discharge region very effectively, and the heating by the plasma can be used effectively. A tonic effect can be obtained.
[0027]
(4) In addition, oxygen or a plurality of oxygen-containing gases are introduced into a reaction vessel containing a processing tray loaded with an ion exchange resin to be processed to create an oxygen-containing atmosphere, and discharge is caused by the electromagnetic field action of the wound high-frequency induction coil. In the ion exchange resin volume reduction treatment method, the active oxygen generated by the discharge is caused to act on the ion exchange resin to be treated from above in the vertical direction to reduce the amount of ash, and the treatment dish is installed in the gas inlet of the reaction vessel. The distance between the high-frequency induction coil and the ion exchange resin to be treated is moved in the vertical direction within the region having the height as the lower end and the installation height of the reaction vessel exhaust port as the upper end, depending on the properties of the ion exchange resin to be treated. If the method of ashing and reducing the ion exchange resin to be treated is adjusted and the distance between the high frequency induction coil and the ion exchange resin to be treated is adjusted according to the situation of the ion exchange resin to be treated, Since it is possible to adjust the temperature rise of the ion-exchange resin to be treated due to laser heating, the amount of pyrolysis vaporized gas can be adjusted according to the amount of active species generated, and complete oxidation in the gas phase is realized. Therefore, it is extremely suitable as a volume reduction treatment method for ion exchange resins.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view schematically showing a basic configuration of a first embodiment of an ion exchange resin volume reducing apparatus according to the present invention.
FIG. 2 is a cross-sectional view schematically showing a basic configuration of a second embodiment of the ion exchange resin volume reducing apparatus according to the present invention.
FIG. 3 is a cross-sectional view schematically showing a basic configuration of a third embodiment of the ion exchange resin volume reducing apparatus according to the present invention.
FIG. 4 is a cross-sectional view schematically showing a basic configuration of a fourth embodiment of the ion exchange resin volume reducing apparatus according to the present invention.
FIG. 5 is a cross-sectional view schematically showing a basic configuration of a fifth embodiment of the ion exchange resin volume reducing apparatus according to the present invention.
FIG. 6 is a cross-sectional view schematically showing a configuration example of a conventional ion exchange resin volume reduction apparatus using a high frequency induction coil.
FIG. 7 is a cross-sectional view schematically showing another configuration example of a conventional ion exchange resin volume reducing apparatus using a high frequency induction coil.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1A Discharge vessel 2B Reaction vessel 3 Ion exchange resin 4 Processing dish 5 Gas inlet 9A, 9B, 9C High frequency induction coil 10 High frequency generator 11 Exhaust port 12, 12A Discharge / reaction vessel 21 Moving mechanism 22 Moving stage 31 Flat plate window

Claims (3)

A reaction vessel containing a processing tray loaded with an ion exchange resin to be treated; a decompression unit that puts the reaction vessel in a depressurized state; a gas introduction unit that introduces oxygen or a plurality of gases containing oxygen into the reaction vessel; Alternatively, a plurality of gases containing oxygen are introduced, discharge is generated by the electromagnetic field effect of the wound high frequency induction coil, and the active oxygen generated by the discharge is applied to the ion exchange resin to be treated from the upper part in the vertical direction to reduce ashing. In the ion exchange resin volume reduction processing equipment
A reaction in which at least the upper end surface of the exhaust port of the reaction vessel connected to the pressure reducing means is arranged at a position higher than the upper end of the ion exchange resin to be processed loaded on the processing dish and connected to the gas introducing means. At least the lower end surface of the gas inlet of the container is arranged at a position lower than the lower end of the processing dish ,
An ion exchange resin volume reduction treatment apparatus , wherein a treatment tray on which an ion exchange resin to be treated is loaded is arranged on a movable stage movable in a vertical direction . On the upper surface in the vertical direction of the reaction vessel, a flat window made of an electrically insulating material is arranged opposite to the ion exchange resin to be processed loaded on the processing dish, and a high frequency induction coil is installed on the top. The ion exchange resin volume-reduction processing apparatus according to claim 1. An oxygen-containing atmosphere is introduced by introducing oxygen or a plurality of oxygen-containing gases into a reaction vessel containing a treatment tray loaded with the ion exchange resin to be treated, and a discharge is generated by the electromagnetic field action of the wound high-frequency induction coil. In the ion exchange resin volume reduction treatment method, the active oxygen generated by the above is caused to act on the ion exchange resin to be treated from the upper part in the vertical direction to reduce the ashing volume.
The processing dish is moved in the vertical direction within a region having the installation height of the gas inlet of the reaction vessel as the lower end and the installation height of the exhaust port of the reaction vessel as the upper end, depending on the properties of the ion exchange resin to be treated. Then, the ion exchange resin volume reduction processing method is characterized by adjusting the distance between the high-frequency induction coil and the ion exchange resin to be treated and ashing and reducing the volume of the ion exchange resin to be treated.

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