KR102005680B1 - Methods for Treatment of Spent Radio- active Ion-Exchange Resin - Google Patents

Abstract

The present invention relates to a method for treating a waste radioactive ion exchange resin which is able to treat a waste radioactive ion exchange resin by performing an oxidative degradation of the waste radioactive ion exchange resin into carbon dioxide (CO2) and water (H2O), which are stable inorganic materials, comprising: a step of mixing the waste ion exchange resin with water in a mixing tank, and to transfer the mixture to a reaction tank; a step of pre-treatment to build a reduction electrode inside the reaction tank, to form an oxidative degradation condition of the waste ion exchange resin, and to put in a catalyst for activating an oxidation degradation reaction; and a step of oxidative degradation to apply a power to the reduction electrode and to perform an oxidative degradation by injecting a hydrogen peroxide (H2O2) into the reaction tank. Accordingly, the present invention is able to perform an oxidative degradation of the waste ion exchange resin in water at a low temperature, to promote safety in the treatment process, to generate no volatile radioactive material, to generate no dust, tar, or the like, to have a very great volume reduction rate, to generate a very small volume of secondary wastes, to form an atmosphere with concentrated oil of vitriol and nitric acid, to minimize a used volume of H2O2, which is an oxidizing agent, to minimize a used volume of catalyst by using the reduction electrode, and to reduce the cost for degradation and treatment of the waste ion exchange resin.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for treating radioactive waste ion exchange resin,

The present invention radioactive waste to ion exchange on resin processing method, more particularly to a nuclear reactor cooling water purifying system and the liquid waste radioactive waste ion exchange resin, a stable inorganic carbon dioxide (CO ₂₎ and water generated by the processing system (H ₂ O) by oxidative decomposition with a radioactive waste ion exchange resin.

Nuclear power plants generate various radionuclides due to the neutrons generated from the nuclear fuel. These nuclides stay in the system for a long time and deposit on the surface of the system piping in the form of radioactive crud (CRUD) to form a high radiation field. This causes radiation workers to receive unwanted radiation exposure during the maintenance period of the plant.

In order to lower the radiation field in the reactor system, microfiltration technology that removes particulate crud by using zinc injection technology or microfiltration filter injecting zinc (Zn) into the system, And an ion exchange resin purification technique in which existing nuclides are removed by ion exchange. Among them, the best radioactive material removal technology is an ion exchange treatment technology using ion exchange resin, and this technology is widely used in nuclear power plants.

This ion exchange treatment technique is the most preferred technique because of its excellent removal efficiency of radioactive ions and simple process, but due to the nature of the ion exchange resin, ionic substances which are not radioactive and radioactive ionic substances are removed together The life of the ion exchange resin is shortened. As a result, a large amount of radioactive waste ion exchange resin is generated annually. Usually, after one week of operation, the entire amount of ion exchange resin needs to be changed. Therefore, about 3 tons of waste ion exchange resin per unit discharge is generated in the power plant every year.

The generated waste ion-exchange resin is stabilized with cement or polymer or dehydrated in a High Integrity Container (HIC) with a life span of 300 years or more and sent to a permanent disposal site. Until then, it has been stored and managed in temporary storage in the nuclear power plant site. However, since the radioactive contaminated resin at low level is difficult to handle and the operation mode of the repository is different in each country, the transportation to the repository should take into account economic efficiency and safety of handling first.

Since the ion exchange resin exhibits swelling property upon contact with water due to the hydrophilic group exhibiting ion exchange ability in the organic synthetic polymer material, a strong swelling pressure is applied to the solidification medium. Therefore, when the solidification treatment with cement is performed, there is a limit in the waste volume abatement ratio, , The penetration diffusion rate of water is high and the possibility of leaching of radionuclides is also high.

In the United States, which operates more than 130 units, the ion exchange resins from most nuclear power plants are not solidified, but are immediately dehydrated and transferred to a disposal facility in a high-integrity container (HIC) for disposal . However, such a disposal method must meet the stringent test conditions required to demonstrate that the integrity of the container is maintained for more than 300 years, and the cost of disposal increases due to the use of expensive containers.

Korea and Japan are not treated as containers in the US due to restrictions on disposal sites, and the use of waste disposal technology is recommended to minimize the amount of waste sent to disposal sites.

The waste ion exchange resin, which is a polymer substance, is decomposed into CO ₂ and H ₂ O and then stabilized in an inorganic form. Therefore, the effect of volume reduction is large, swelling properties of the ion exchange resin and radiation decomposition of organic materials can be prevented Volatile radioactive materials are generated in the pyrolysis process, the recovery of radioactive materials is difficult, dust and tar are generated, and secondary waste is generated in a large amount. This patent has been described in order to solve such a problem.

KR 10-1624453 B

In order to solve the above problems, the present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a waste water treatment method and a waste water treatment method for waste ion exchange resin generated from a nuclear power plant, And a method of decomposing and treating CO ₂ and H ₂ O which are stable inorganic forms.

The method for treating radioactive waste ion-exchange resin of the present invention is characterized by comprising a mixing step of mixing waste ion exchange resin with water in a mixing tank and transferring the water to a reaction tank, placing a reducing electrode in the reaction tank, And an oxidation decomposition step of oxidizing and decomposing hydrogen peroxide (H ₂ O ₂ ) by applying power to the reduction electrode and injecting hydrogen peroxide into the reaction vessel. In addition, the present invention may further comprise a separation step of separating the final by-product into a solid phase, a liquid phase, and a vapor phase, and a finishing step of processing the final by-product separated in the oxidation decomposition step and the separation step.

The present invention decomposes a waste ion exchange resin generated in a nuclear power plant into CO ₂ and H ₂ O, which are stable inorganic forms, by oxidizing and decomposing the waste ion exchange resin to a low temperature in water. Therefore, safety is ensured in the treatment process and volatile radioactive materials And there is no dust or tar.

In addition, since the final by-product is changed into inorganic form of CO ₂ and H ₂ O, unlike the plastic or cement solidifying method, the volume rejection rate is extremely large and the amount of generated secondary waste is extremely small have.

Further, the present invention minimizes the amount of H ₂ O ₂ used as an oxidizing agent and minimizes the amount of catalyst used by using a reducing electrode by forming a concentrated sulfuric acid and nitric acid atmosphere, thereby reducing the decomposition treatment cost of the spent ion exchange resin.

1 is a block diagram of a waste ion exchange resin oxidative decomposition process of the present invention.
2 is a block diagram of a laboratory-scale waste ion exchange resin oxidative decomposition apparatus of the present invention.
FIG. 3 is a graph showing the efficiency of ion exchange resin decomposition according to the concentration change of Mole per catalyst. Figure 3a shows the case of cationic resin and Figure 3b shows the case of anionic resin.
FIG. 4 is a graph showing decomposition effects according to the change of the same mole ratio and the addition amount of H ₂ O ₂ when the catalyst is used in combination. Fig. 4A shows a case of a cation resin, and Fig. 4B shows a case of an anionic resin.
FIG. 5 is a graph showing decomposition effects according to changes in H ₂ O ₂ injection amount per catalyst. FIG. 5A shows a case of a cation resin, and FIG. 5B shows a case of an anionic resin.
FIG. 6 is a graph illustrating the decomposition effect according to the variation of the mixing mole ratio at a constant Mole concentration. Fig. 6A shows a case of a cationic resin, and Fig. 6B shows a case of an anionic resin.
FIG. 7 is a graph showing the decomposition effect according to the concentration change of the Mole when the mixed catalyst of the same mole ratio is used. FIG. 7A shows a case of a cationic resin, and FIG. 7B shows a case of an anionic resin.

The present invention relates to a method for oxidizing and decomposing a waste ion exchange resin (a cation exchange resin, an anion exchange resin and a mixed resin) generated in a nuclear power plant or the like to a low temperature (85 to 100 ° C) in water using a wet oxidation method, And decomposes into CO ₂ and H ₂ O in the form.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in detail with reference to the accompanying drawings.

1 and 2, the method for treating radioactive waste ion-exchange resin according to the present invention comprises a mixing step (P1) in which a waste ion-exchange resin is mixed with water in a mixing tank (1) and transferred to a reaction tank (2) A pre-treatment step (P2) in which a reducing electrode is laid in the reaction tank (2), a condition for oxidative decomposition of a waste ion exchange resin is established, and a catalyst for activating an oxidative decomposition reaction is charged; And an oxidative decomposition step (P3) for oxidizing and decomposing hydrogen peroxide (H ₂ O ₂ ) into the reaction tank (2)

The present invention also relates to a method for producing a final product, comprising: a separation step (P4) of separating the final byproduct into solid phase, liquid phase and gaseous phase; a finishing step (P5) for processing the final byproduct separated in the oxidative decomposition step (P3) As shown in FIG.

In the mixing step (P1), the separately stored waste ion-exchange resin is transferred to the mixing tank (1) and mixed with water in the mixing tank (1). The waste ion exchange resin is transferred to the compounding tank 1 by using the first transfer pump and then mixed with water in the compounding tank 1 so that the waste ion exchange resin is in a slurry state. A predetermined amount of waste ion exchange resin is transferred to the reaction tank 2 by using a second transfer pump.

The first feed pump is preferably a pump capable of controlling the flow rate to 0.5 m ³ / hr, and the second feed pump is preferably a peristatic pump. It is preferable to use a screen having a corrosion resistance of SUS316 and a size of 50mesh or less when it is mixed with an appropriate amount of water and waste ion exchange resin and then sent to the reaction vessel (2) in order to filter the impurities beforehand .

In the pre-treatment step (P2), the pH and the temperature of the slurry-containing waste ion exchange resin are adjusted, and the catalyst is injected to activate the oxidative decomposition reaction. In addition, a reducing electrode capable of applying power is laid inside the reaction tank (2). Of course, such a reducing electrode may be provided before the pre-treatment step (P2).

Sulfuric acid or nitric acid, the pH of the cationic resin is adjusted to 1.5 to 4.1, and the pH of the anionic resin is adjusted to 2.0 to 3.0. The internal temperature is adjusted to a low temperature of 100 ° C or less.

Iron (FeSO4) catalyst and copper (CuCl, CuSO ₄ ) cocatalyst are used as a catalyst for activation of the oxidative decomposition reaction, and the mixing mole ratio is maintained at 0.002 mole or more. Hereinafter referred to as iron (FeSO4) catalyze the Fe catalyst, copper (CuCl, CuSO ₄₎ a cocatalyst a Cu cocatalyst, copper (CuCl) CuCl provides a cocatalyst catalyst, copper (CuSO ₄₎ CuSO ₄ provides a cocatalyst catalyst .

In the oxidative decomposition step (P3), a power of 0.6 to 1.0 Volt is applied to the reducing electrode and H ₂ O ₂ is injected at a rate of 100 to 180 ml / hr to cause oxidative decomposition. The decomposition rate varies depending on the injection amount and the injection rate of H ₂ O ₂ . Since the heat is generated by the oxidative decomposition reaction, the injection amount and the injection rate of H ₂ O ₂ are adjusted so that the temperature inside the reaction tank 2 is maintained at an appropriate temperature (85-100 ° C.). It is preferable to use a Pt electrode in consideration of the lifetime of the electrode.

In the separating step P4, the oxidative decomposition product generated after the oxidative decomposition reaction in the oxidative decomposition step P3 is transferred to the decompression evaporator 3, the pressure inside the decompression evaporator 3 is reduced to 740 Torr, Deg.] C, and the oxidative decomposition product is separated into a solid phase, a liquid phase and a vapor phase through a reduced pressure evaporation process.

In the finishing step (P5), the oxidative decomposition products separated into the solid phase, the liquid phase and the vapor phase are treated in the oxidation decomposition step (P3) and the separation step (P4). A steam condensing process T1 for condensing water vapor generated in the oxidative decomposition step P3 into a heat exchanger 4 and a condensing water separation process for separating the condensed water separated in the water vapor condensation process T1 and the separation process P4 (T3) for purifying the condensed water collected in the condensed water collecting process (T2) by the condensed water purifying device (6) and the separation (7) for collecting the condensed water in the condensed water collecting process A bottom material collecting step (T4) for collecting the bottom material remaining at the time of the reduced pressure evaporation in the step P4; a step for purifying the exhaust gas separated in the separating step (P4) in the exhaust gas treating device (8) (T5), which decomposes into THC, CO, Sox and residual organic matter using a high-efficiency particulate air filter (HEPA) to remove volatile heavy metals.

The water generated in the condensate purification process (T3) is discharged to the outside, the solid is treated as solid waste, and the bottom material collected in the bottom material collecting process (T4) is processed in a drum. In addition, CO ₂ separated in the separation step (P4) and exhaust gas treated in the exhaust gas treatment process (T4) are discharged through an HVAC system (Heating, Ventilation Air Conditioning System).

Next, the decomposition effect in the oxidative decomposition step (P3) will be described.

FIG. 3 is a graph showing the efficiency of ion exchange resin decomposition according to the concentration change of Mole per catalyst. Figure 3a shows the case of cationic resin and Figure 3b shows the case of anionic resin. 0.0005, 0.0015, 0.0045, 0.0090 and 0.0135 mole of H ₂ O ₂ were injected at a rate of 100 ml / hr, respectively, using an Fe catalyst, a CuCl catalyst and a CuSO ₄ catalyst as individual catalysts. And the decomposition rate according to the addition amount of each catalyst was confirmed.

In the case of the cation exchange resin, as shown in FIG. 3A, the decomposition rate when the amount of the Fe catalyst was 0.0135 mole with respect to 5g of the dried resin was 92%, which was lower than that with 0.009 mole showing the decomposition rate of 96% The maximum decomposition rate was about 0.009 mole. This reaction is based on the reaction of Fe ions.

가 H₂O₂와 반응하여

로 산화를 하면서

라디칼을 생성시키고, 생성된

가 산화 분해의 주된 원인으로 작용하고 있다고 볼 수 있다. 따라서 도 3a에서 도시된 것처럼 Fe 촉매의 양이 많아짐에 따라

라디칼의 생성이 많아지고 반응성이 커져서 분해율이 높아진다.As shown in the above equation

Reacts with H ₂ O ₂

While oxidizing

Radicals, and the resulting

Is the main cause of oxidative decomposition. Therefore, as shown in FIG. 3A, as the amount of the Fe catalyst increases,

The generation of radicals is increased, the reactivity is increased, and the decomposition rate is increased.

On the other hand, when the anion exchange resin by changing the addition amount of Fe and Cu catalyst catalyst as shown in the following tailored, 3b such that the pH 2 with sulfuric acid and the anion exchange resin 15.775g (by dry weight 5g) H ₂ O ₂ Injection rate of 100 ml / hr was injected in total of 100 ml, and the decomposition rate was confirmed by the change of catalyst addition amount. As shown in FIG. 3B, as the amount of the Fe catalyst and the amount of the Cu catalyst increased, the decomposition ratio increased. When the amount of the Fe catalyst and the Cu catalyst increased, the decomposition rate decreased again.

The reason why the decomposition rate is lower than that of the cationic resin is that the anion exchange resin has a carbon content of about 1.3 times as much as that of the cation exchange resin so that the decomposition rate of H ₂ O ₂ used for the decomposition of the cation exchange resin This is because more H ₂ O ₂ is required than the amount.

As described above, when a single catalyst is used, the cationic resin has the highest decomposition rate of the Fe catalyst, while the anion resin has the highest decomposition rate of the CuCl catalyst. Cationic resins showed a decomposition rate of more than 94% at over 0.0045 mole. In the case of anion resin, the decomposition rate of CuCl catalyst was more than 75% at more than 0.0045 mole. Therefore, when using a single catalyst, it is preferable to set the mole concentration to 0.004 mole or more, select the catalyst according to the applied resin, and keep the H ₂ O ₂ injection rate at 100 ml / hr or more.

FIG. 4 is a graph showing decomposition effects according to the change of the same mole ratio and the addition amount of H ₂ O ₂ when the catalyst is used in combination. Fig. 4A shows a case of a cation resin, and Fig. 4B shows a case of an anionic resin. The decomposition rate of the resin was confirmed under each condition while applying a power of 0.771Volt to the reducing electrode and increasing the amount of H ₂ O ₂ injected (injection rate: 100 ml / hr) in the same mole ratio.

In the case of the cation exchange resin, as shown in FIG. 4A, when the molar ratio was increased to 0.002 mole or more in the same mole ratio, the decomposition rate was high at the time of injection of 100 ml or more of H ₂ O ₂ , ₂ O ₂ injection amount. On the other hand, when the sum of the Fe catalyst and the CuCl cocatalyst is 0.001 mole, the decomposition ratio increases proportionally with the amount of H ₂ O ₂ injected, but a large amount of H ₂ O ₂ is required to obtain a high decomposition rate of 95% or more Respectively.

In order to investigate the change of decomposition rate according to the injection rate of H ₂ O _2, the injection rate of H ₂ O ₂ was decreased from 100 ml / hr to 50 ml / hr when the sum of mole was 0.002 mole, , And the injection rate of H ₂ O ₂ is closely related to the decomposition rate.

From the results of the oxidative decomposition reaction of the cation exchange resin, it can be seen that the decomposition efficiency is higher than the case of using the single catalyst, and the decomposition efficiency is also improved according to the injection rate of H ₂ O ₂ . Also, since the amount of H ₂ O ₂ injected can be significantly reduced when the amount of catalyst used is increased, the amount of catalyst and the rate of injection of H ₂ O ₂ are determined by considering the amount of waste generated and the economical aspect do.

In the case of the anion resin, as shown in FIG. 4B, when the Mole sum of the Fe catalyst and the CuCl cocatalyst was 0.002 mole or more, over 100 ml of H ₂ O ₂ showed a decomposition rate of 98% or more at the time of injection. However, at 0.001 mole of Fe catalyst and CuCl cocatalyst, the decomposition rate is more than 98% at the injection of 175 ml or more, and it is understood that the amount of H ₂ O ₂ should be used relatively when the amount of catalyst is small .

In the case of the anionic resin, as in the case of the cation resin, the injection rate of H ₂ O ₂ was reduced to 50 ml / hr under the condition of 0.002 mole of the catalyst, and as a result, 99% Efficiency.

FIG. 5 is a graph showing decomposition effects according to changes in H ₂ O ₂ injection amount per catalyst. FIG. 5A shows a case of a cation resin, and FIG. 5B shows a case of an anionic resin. To the cation exchange resin, 0.009 mole of Fe catalyst was added, and a power of 0.77 volts was applied to the reducing electrode. The reaction temperature was changed to 100 ° C. and the amount of H ₂ O ₂ injected was changed from 100 ml to 110, 120, 130, 140 and 150 ml And the decomposition rate was confirmed while changing.

As shown in FIG. 5A, in the case of the cation exchange resin, the decomposition ratio also increased when the amount of H ₂ O ₂ was increased. Showed a decomposition rate of 95% or more if the amount of H ₂ O ₂ over time 100㎖ into the Fe catalyst in catalytic cracking sikyeoteul oxide, in the above 150㎖ indicate the decomposition rate of 99% or more over the almost complete oxidation done, only CuSO ₄ catalyst When used, the decomposition rate was low.

On the other hand, Fe catalyst and CuSO ₄ ball when mixing the catalyst while the reaction solution was obtained by changing the amount of H ₂ O ₂ H ₂ O _2, the injected amount the degradation rate are both indicated by 99% or more above 100㎖ excess H ₂ O ₂ and Fe catalyst and CuSO ₄ cocatalyst were used, the complete oxidation decomposition occurred.

From the economical viewpoint of the amount of H ₂ O ₂ and the amount of catalyst injected for oxidizing and decomposing a certain amount of the cation exchange resin, the ratio of hydrogen peroxide / resin is about 20 or more when using only H ₂ O ₂ without using a catalyst H ₂ O ₂ . However, as described above, since the amount of H ₂ O ₂ is remarkably reduced when a catalyst is used, it is economically advantageous to oxidize and decompose by injecting a certain amount of catalyst.

In the case of the anion resin, as shown in FIG. 5B, it was greatly influenced by the amount of H ₂ O ₂ injected. H ₂ O ₂ injected amount was varied from 100 to 200 ml. As a result, when the Fe catalyst alone was used and when the Fe catalyst and the CuSO ₄ cocatalyst were mixed, the amount of H ₂ O ₂ injected was more than 200 ml The decomposition rate was about 93%.

In the reaction process due to the oxidative decomposition of the ion exchange resin, some of the catalysts become sludge, so that the concentration of the catalyst in the reaction solution after the termination of the reaction is decreased. However, if the concentration of the catalyst before and after the reaction is within the range of 0.0005 to 0.02 mole, there is no great problem. From this series of results, it is economically important to keep the concentration of Fe catalyst at a somewhat low level under conditions of high decomposition rate. It is generally known that the catalytic action of Fe catalyst and CuSO ₄ cocatalyst on H ₂ O ₂ is centered on Fe ion cycle as follows.

(1)

(One)

(2)

(2)

(3)

(3)

(4)

(4)

(5)

(5)

(6)

(6)

(7)

(7)

FIG. 6 is a graph illustrating the decomposition effect according to the variation of the mixing mole ratio at a constant Mole concentration. Fig. 6A shows a case of a cationic resin, and Fig. 6B shows a case of an anionic resin. The ratio of Fe catalyst to Cu cocatalyst is 0.002 mole or less based on 0.002 mole, which shows a relatively high decomposition rate when a single catalyst is used to compare the decomposition rates when a single catalyst is used and when a cocatalyst is mixed. The decomposition ratio was confirmed by changing the ratio. A power source of 0.771 volts was applied to the reducing electrode, and H ₂ O ₂ At a constant rate of 100 ml / hr.

In the case of the cation exchange resin, as shown in FIG. 6A, it is observed that the decomposition ratio is improved when the ratio of the mixed catalyst is fixed to 0.002 Mole and the ratio of the catalyst is changed when the Fe catalyst or the Cu catalyst alone is used there was.

이 촉매반응에서

의 도움을 받아

로 쉽게 환원되어 반응을 촉진시키기 때문이다. 즉,

의 도움에 의해서 적은 촉매량을 사용하고도 높은 분해율을 얻는 것이 가능하기 때문이다.This is because, as shown in the above reaction formula,

In this catalytic reaction

With the help of

To facilitate the reaction. In other words,

It is possible to obtain a high decomposition rate even if a small amount of catalyst is used.

While the sum of the amount of catalyst mixture was fixed at 0.002 mole, the Fe catalyst 0.001: 0.001 mole of CuCl cocatalyst 1: 1, Fe catalyst The decomposition rate was more than 95% at 0.0015: 0.0005 mole of 3: 1 CuSO ₄ cocatalyst.

In the case of the anion exchange resin, as shown in FIG. 6B, no remarkable increase in the decomposition rate was observed when the Cu cocatalyst was used together, as compared with the case where only the single catalyst was used. When the ratio of CuCl cocatalyst / Fe catalyst was about 5, the decomposition rate was the highest at 79.67% and the decomposition ratio was 82.76% at the ratio of Fe catalyst / CuSO ₄ cocatalyst was 2. This is because the anion resin generally has a carbon content of about 1.3 times higher than that of the cation resin, and the amount of H ₂ O ₂ consumed by the resin decomposition is high.

FIG. 7 is a graph showing the decomposition effect according to the concentration change of the Mole when the mixed catalyst of the same mole ratio is used. FIG. 7A shows a case of a cationic resin, and FIG. 7B shows a case of an anionic resin. H ₂ O ₂ 100 ml / hr to confirm the decomposition rate.

In the case of the cation exchange resin, as shown in FIG. 7 (a), the sum of Fe catalyst and Cu cocatalyst amount should be at least 0.003 mole to reach a satisfactory level of 99% or more.

In the case of the anion exchange resin, as shown in FIG. 7B, the Fe catalyst and the Cu cocatalyst each had a decomposition rate of 95% or more when they were each 0.001 mole or more, respectively. The bubbles were not generated rapidly without the addition of defoamer, because the content of the intermediate compound, which has a considerable viscosity and a larger molecular weight, was lowered, thereby suppressing the occurrence of intense bubbles.

As described above, the decomposition effect of the cation exchange resin was about 1/3 Mole when the cation exchange resin was decomposed and the cocatalyst was mixed with the anion exchange resin about 1 / 4.5 mole.

As described above, the present invention decomposes a waste ion exchange resin generated in a nuclear power plant into CO ₂ and H ₂ O, which are oxidized and decomposed in a low temperature in water, and is processed to secure safety in the treatment process, and volatile radioactive materials It does not occur, and dust or tar does not occur.

In addition, since the final byproduct is changed into inorganic substances CO ₂ and H ₂ O, unlike the method of solidifying plastics or cement, the volume reduction rate is very large and the amount of generated secondary waste is very small.

In addition, the present invention minimizes the amount of H ₂ O ₂ used as an oxidizing agent by forming a concentrated sulfuric acid and nitric acid atmosphere and minimizes the amount of catalyst used by using a reducing electrode, thereby reducing the decomposition treatment cost of the spent ion exchange resin.

While the present invention has been described with reference to the exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but is capable of various changes and modifications within the technical scope of the invention. Therefore, the scope of the present invention is not limited by the above description.

The present invention is not limited to the above-described embodiments, and various changes and modifications may be made without departing from the scope of the present invention.

1: mixing tank 2: reaction tank
3: decompression evaporator 4: heat exchanger
5: Condensate collecting tank 6: Condensate purifying device
7: Dust collector 8: Exhaust gas treatment device
P1: mixing step P2: preprocessing step
P3: Oxidative decomposition step P4: Separation step
P5: Finishing step T1: Water vapor condensation process
T2: Condensate collection process T3: Condensate purification process
T4: Flooring material collection process T5: Exhaust gas treatment process

Claims (9)

A method of treating a radioactive waste ion exchange resin,
A mixing step (P1) of mixing the waste ion exchange resin with water in the compounding tank (1) and transferring it to the reaction tank (2)
A pre-treatment step (P2) in which a reducing electrode is laid in the reaction tank (2), a condition for oxidative decomposition of the waste ion exchange resin is established, and a catalyst for activating the oxidative decomposition reaction is added;
An oxidizing and decomposing step (P3) for applying power to the reducing electrode and oxidizing and decomposing hydrogen peroxide (H ₂ O ₂ ) into the reaction tank (2)
A separation step (P4) of separating the final byproduct into a solid phase, a liquid phase and a vapor phase, and
And a finishing step (P5) of treating the final by-product separated in the oxidative decomposition step (P3) and the separation step (P4)
The finishing step (P5)
A steam condensing step (T1) of condensing water vapor generated in the oxidative decomposition step (P3) into a heat exchanger (4)
A condensation water collecting step (T2) for collecting the condensed water separated in the water vapor condensing step (T1) and the separating step (P4) into a condensed water collecting tank (5)
A condensate water purification step (T3) for purifying the condensed water collected in the condensed water collection step (T2) by the condensed water purification device (6)
A bottom material collecting step (T4) for collecting the bottom material remaining at the time of reduced pressure evaporation in the separating step (P4) by using the dust collecting device (7)
The exhaust gas separated in the separation step (P4) is decomposed into THC, CO, Sox and residual organic matter by using a catalyst in the exhaust gas treatment device (8) in order to reduce the amount of waste generated, and a HEPA filter (High Efficiency Particulate Air Filter (T5) which removes volatile heavy metals by using a radioactive waste ion exchange resin (T5).
delete delete The method according to claim 1,
Wherein the pH in the reaction tank (2) is controlled in the range of 1.5 to 4.1 in the case of the cation resin and in the range of 2.0 to 3.0 in the case of the anion resin in the pretreatment step (P2) Processing method.
The method according to claim 1,
Radioactive waste ion exchange resin processing method, characterized in that in the pre-treatment step (P2) to use iron (FeSO4) catalyst and copper (CuCl, CuSO ₄₎ a cocatalyst with the catalyst and 0.002 to mix Mole ratio remains Mole above.
The method according to claim 1,
Wherein the oxidizing and decomposing step (P3) comprises applying a power of 0.6 to 1.0 Volt to the reducing electrode.
The method according to claim 1,
Wherein the temperature in the reaction tank (2) is maintained at 85 to 100 DEG C in the oxidative decomposition step (P3).
The method according to claim 1,
Wherein the hydrogen peroxide (H ₂ O ₂ ) is injected at a rate of 100 to 180 ml / hr in the oxidative decomposition step (P3). delete

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