A device for purifying radioactive iodine and aerosol

Abstract

The present invention relates to a radioactive iodine and aerosol purification device, which utilizes ozone to oxidize radioactive iodine into iodine oxide, thereby forming aerosol particles, and a high-voltage generating system makes the aerosol particles charged in a high-voltage electric field, so that the aerosol particles are subjected to the electric field force and are collected on the cylinder wall of an electrostatic purification chamber, and a spray flushing system can use a certain concentration of alkali solution to flush the cylinder wall, thereby washing the radioactive aerosol particles adsorbed on the cylinder wall into the alkali solution, and finally fixing the radioactive aerosol particles in the gas in a fine water filter. The radioactive iodine and aerosol purification device disclosed by the present invention has the effect of purifying radioactive aerosol and radioactive iodine at the same time, reduces the operation and maintenance costs caused by replacing traditional iodine adsorbers and high-efficiency filter devices, and reduces the amount of solid waste caused by replacing traditional iodine adsorbers and high-efficiency filters.

Description

Technical Field

[0001] The invention belongs to the field of air purification, and in particular relates to a radioactive iodine and aerosol purification device. Background Art

[0002] At present, the ventilation system or radioactive gas treatment system of nuclear power plants or other nuclear facilities uses high-efficiency filters to filter out radioactive aerosols in the air or gas, and uses iodine adsorbers filled with impregnated particulate activated carbon to adsorb and purify radioactive iodine (including elemental iodine, organic iodine and other radioactive iodine compounds). These high-efficiency filters and impregnated particulate activated carbon iodine adsorbers are divided into different types of radioactive waste according to the amount of radioactivity filtered or adsorbed by them. Different radioactive wastes are treated differently, thereby increasing the cost of treatment and disposal of radioactive wastes.

[0003] In addition, the above-mentioned disposal method requires replacement of the iodine adsorber and the high-efficiency filter, thereby increasing the maintenance and operation costs of the system. Summary of the invention

[0004] In view of the defects existing in the prior art, the purpose of the present invention is to provide a radioactive iodine and aerosol purification device, which has both radioactive aerosol and radioactive iodine purification functions, and at the same time the device has a long service life and does not need to be replaced regularly. The removed radioactive substances are washed into the solution by spraying, and are fixed in the filter of the solution spraying system after circulating purification, which greatly reduces the operating and maintenance costs caused by replacing iodine adsorbers and high-efficiency filters, and also greatly reduces the amount of solid waste generated by the nuclear power plant waste gas treatment system, reducing the cost of treatment and disposal of radioactive waste.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is: a radioactive iodine and aerosol purification device, comprising a device shell, an electrostatic purification chamber, a high-voltage generating system, a spray flushing system and an ozone supply system, wherein the device shell is provided with an exhaust gas inlet and an exhaust gas outlet, the electrostatic purification chamber is arranged in the device shell, the exhaust gas inlet is connected to a first side of the ozone supply system, the second side of the ozone supply system is connected to a first side of the high-voltage generating system, the second side of the high-voltage generating system is connected to the exhaust gas outlet, the lower side of the spray flushing system is located at the lower side of the electrostatic purification chamber, and the upper side of the spray flushing system extends to the upper side of the inner cylinder of the electrostatic purification chamber;

[0006] The ozone supply system is used to generate a certain concentration of ozone, which, after mixing with the airflow, oxidizes the radioactive iodine in the airflow into aerosol particles containing iodine oxide;

[0007] The high voltage generating system is used to generate a high voltage electrostatic field inside the electrostatic purification chamber to charge the aerosol particles in the airflow, so that the aerosol particles are affected by the electric field force and are collected on the cylinder wall of the electrostatic purification chamber;

[0008] The spray flushing system is used to extract alkali solution of a certain concentration to flush the cylinder wall of the electrostatic purification chamber, so as to clean the aerosol particles adsorbed on the cylinder wall in the solution pool of the spray flushing system.

[0009] Furthermore, the spray flushing system includes a fine water filter and a circulating water pump. The solution in the solution pool is circulated and purified through the filter to fix the aerosol particles in the air flow in the filter. The purified alkali solution can be sprayed again through the high-pressure circulating pump.

[0010] Furthermore, the device also includes a water mist generating system, which is arranged between the exhaust gas inlet and the ozone supply system. The water mist generated by the water mist generating system enters the purification device along with the air flow through the Venturi structure on the water mist diffusion chamber.

[0011] Furthermore, the water mist generating system extracts the solution in the solution pool to generate water mist.

[0012] Furthermore, the device also includes a cooling circulation system, which is arranged at the top of the electrostatic purification chamber, and the cooling circulation system is arranged between the high-voltage generating system and the exhaust gas outlet. The cooling circulation system is used to cool the inner cylinder of the electrostatic purification chamber to reduce the air flow temperature.

[0013] Furthermore, the device also includes an air-water separation system, which is arranged before the exhaust gas outlet. The air-water separation system removes moisture from the airflow by using the centrifugal force of the rotating blades under the support of the blade bearing.

[0014] Furthermore, the filter is replaceable, the solution nozzle of the spray flushing system is located above the inner cylinder of the electrostatic purification room, the spray liquid sprayed by the solution nozzle can 100% cover the inner cylinder range of the electrostatic purification room, and the spray flushing system can choose to spray alkali solution or water by switching the valve.

[0015] Furthermore, the alkali solution includes a NaOH solution.

[0016] Furthermore, the connecting cables of the high voltage generating system are sealed using a through-seal.

[0017] Furthermore, the cooling circulation system includes a heat dissipation circuit, a circulation pump, a cooling medium and a coolant coil, and the coolant coil is spiral.

[0018] The effect of the present invention is that the radioactive iodine and aerosol purification device disclosed in the present invention combines the three technologies of ozone oxidation, high-voltage electric field and solution spraying to be used in the ventilation system or gas treatment system of current nuclear power plants and other nuclear facilities, thereby achieving the effect of purifying radioactive aerosols and radioactive iodine at the same time, thereby reducing the operation and maintenance costs caused by replacing traditional iodine adsorbers and high-efficiency filter devices, and reducing the amount of solid waste caused by replacing traditional iodine adsorbers and high-efficiency filters.

[0019] The ozone supply system uses ozone to oxidize elemental iodine or organic iodine into iodine oxides, thereby forming aerosol particles, which will enter the electrostatic purification chamber with the airflow. The high-voltage generation system uses high voltage electricity to charge the aerosol particles, so that the aerosol particles are collected on the wall of the electrostatic purification chamber under the action of the electric field force to remove the radioactive aerosol particles in the airflow. The spray flushing system mainly uses a certain concentration of NaOH solution to flush the inner wall of the device, thereby washing the radioactive substances adsorbed on the wall of the cylinder in the alkali solution, and circulating purification at the same time, and finally fixing the radioactive substances in the gas in a very small fine water filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of a radioactive iodine and aerosol purification device according to an embodiment of the present invention;

[0021] Among them: 1-waste gas inlet, 2-high voltage generation system, 3-through-seal, 4-electrode support column, 5-high voltage discharge needle, 6-coolant coil, 7-cooling circulation system, 8-solution nozzle, 9-filter, 10-solution pool, 11-spray flushing system, 12-ozone supply system, 13-water mist generation system, 14-gas-water separation system, 15-waste gas outlet, 16-electrostatic purification room. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0023] Embodiment 1

[0024] like Figure 1 As shown, an embodiment of the present invention discloses a radioactive iodine and aerosol purification device, including a device housing, an electrostatic purification chamber 16, an exhaust gas inlet 1, an exhaust gas outlet 15, a high-voltage generating system 2, a spray flushing system 11, an ozone supply system 12, a water mist generating system 13, a cooling circulation system 7, a gas-water separation system 14, and a power supply and control system.

[0025] An exhaust gas inlet 1 is arranged on the device shell, and an electrostatic purification chamber 16 is arranged in the device shell. The exhaust gas inlet 1 is connected to a first side of an ozone supply system 12, a second side of the ozone supply system 12 is connected to a first side of a high-voltage generating system 2, a second side of the high-voltage generating system 2 is connected to a first side of a cooling circulation system 7, a second side of the cooling circulation system 7 is connected to a first side of a gas-water separation system 14, the cooling circulation system 7 is arranged on an upper side of the electrostatic purification chamber 16, a second side of the gas-water separation system 14 is connected to an exhaust gas outlet 15, a lower side of a spray and flushing system 11 is located on a lower side of the electrostatic purification chamber 16, and an upper side of the spray and flushing system 11 extends to an upper side of an inner cylinder of the electrostatic purification chamber 16.

[0026] The ozone supply system 12 is mainly composed of an oxygen generator, a high-pressure ionization chamber and other parts. The oxygen generator produces a relatively high concentration of ozone. The high-concentration ozone oxidizes the radioactive iodine (elemental iodine and organic iodine such as methyl iodide and ethyl iodine) in the airflow under the action of high pressure into aerosol particles containing iodine oxides. After entering the high-voltage generating system 2, the particles are charged in the high-voltage electric field and are collected on the wall of the electrostatic purification chamber 16 under the action of the electric field force to remove the radioactive iodine in the airflow.

[0027] The high voltage generation system 2 includes a transformer, a transmission cable, an electrode support column 4, a high voltage discharge needle 5, a through seal 3 and other parts. The high voltage discharge needle 5 is arranged on the electrode support column 4. The transformer transmits electricity to the high voltage discharge needle 5 through the transmission cable, so that a high voltage electrostatic field is generated inside the electrostatic purification chamber 16. The high voltage generation system uses high voltage electricity to charge aerosol particles, so that the aerosol particles are collected on the cylinder wall of the electrostatic purification chamber 16 under the action of the electric field force to remove radioactive aerosol particles in the airflow. The connecting cable is sealed with a through seal to ensure the airtightness of the purification device.

[0028] The spray flushing system 11 is mainly composed of a solution nozzle 8, a quick-change filter 9, a high-pressure circulation pump and supporting pipelines. The solution nozzle 8 is located above the inner cylinder of the electrostatic purification chamber. The spray liquid sprayed by the solution nozzle 8 can 100% cover the inner cylinder range of the electrostatic purification chamber, thereby cleaning the inner cylinder of the electrostatic purification chamber 16. The cleaned liquid is collected in the solution pool 10 at the bottom of the device, recycled by the high-pressure circulation pump, filtered by the filter 9 and then sprayed, so as to achieve the purification and reuse of the solution and reduce the amount of radioactive waste generated.

[0029] The spray flushing system 11 is also provided with a feeding loop, which can draw alkali solution from an external alkali solution replenishing tank through valve switching to replenish the solution in the spray flushing system, and the alkali solution includes NaOH solution.

[0030] The spray flushing system 11 uses a certain concentration of alkali solution to flush the cylinder wall of the electrostatic purification chamber 16, so that the radioactive substances adsorbed on the cylinder wall are washed in the solution pool 10 of the spray flushing system, and the solution in the solution pool 10 is circulated and purified through the filter 9, and finally the radioactive substances in the airflow are fixed in the filter with a very small volume. The purified alkali solution can be sprayed again through a high-pressure circulation pump to achieve the purification and reuse of the solution, thereby reducing the amount of radioactive waste generated.

[0031] The water mist generating system 13 includes an ultrasonic water mist generator, a water mist diffusion chamber and other parts. The water mist generated by the ultrasonic water mist generator enters the purification device along with the air flow through the Venturi structure on the water mist diffusion chamber, thereby increasing the size and mass of the aerosol particles and making them easier to remove.

[0032] The ultrasonic water mist generator extracts the solution in the solution pool 10 to generate water mist.

[0033] The cooling circulation system 7 includes a heat dissipation circuit, a circulation pump, a cooling medium, a coolant coil 6 and other parts. The coolant coil 6 contains a cooling medium. The cooling medium in the coolant coil 6 cools the inner cylinder of the electrostatic purification chamber 16 to reduce the air flow temperature, so that the moisture contained in the air flow condenses and precipitates, thereby preventing water vapor from carrying out trace amounts of radioactive substances.

[0034] The gas-water separation system 14 includes blade bearings, rotor blades and other parts. Under the support of the blade bearings, the centrifugal force of the rotor blades is used to remove moisture from the airflow to further reduce the humidity of the gas.

[0035] The radioactive iodine and aerosol purification device disclosed in the present invention can be integrated as a whole or arranged in series in subsystems according to the actual situation of the engineering site.

[0036] The operation steps and reaction process of removing radioactive iodine and aerosol by using a radioactive iodine and aerosol purification device disclosed in the present invention are as follows:

[0037] S1. Turn on the high-pressure generating system 2, the ozone supply system 12, the cooling circulation system 7 and the water mist generating system 13 in sequence. After 30 minutes of startup, the radioactive waste gas can be treated.

[0038] S2. Start the spray flushing system 11 every other cycle to clean the inner cylinder.

[0039] S3. When the radioactivity level of the gas source is high, the spray flushing system 11 can be turned on for a long time to improve the purification efficiency of the device.

[0040] It can be seen from the above embodiments that the radioactive iodine and aerosol purification device disclosed in the present invention adopts a combination of three technologies: ozone oxidation, high-voltage electric field and solution spraying, and is used in the ventilation system or gas treatment system of current nuclear power plants and other nuclear facilities, so as to achieve the effect of purifying radioactive aerosols and radioactive iodine at the same time, thereby reducing the operating and maintenance costs caused by replacing traditional iodine adsorbers and high-efficiency filter devices, and reducing the amount of solid waste caused by replacing traditional iodine adsorbers and high-efficiency filters.

[0041] The ozone supply system uses ozone to oxidize elemental iodine or organic iodine into iodine oxides, thereby forming aerosol particles, which will enter the electrostatic purification chamber with the airflow. The high-voltage generation system uses high voltage electricity to charge the aerosol particles, so that the aerosol particles are collected on the wall of the electrostatic purification chamber under the action of the electric field force to remove the radioactive aerosol particles in the airflow. The spray flushing system mainly uses a certain concentration of NaOH solution to flush the inner wall of the device, thereby washing the radioactive substances adsorbed on the wall of the cylinder in the alkali solution, and circulating purification at the same time, and finally fixing the radioactive substances in the gas in a very small fine water filter.

[0042] The device described in the present invention is not limited to the embodiments described in the specific implementation manner. Those skilled in the art may derive other implementation manners based on the technical solution of the present invention, which also fall within the technical innovation scope of the present invention.

Claims

1. A device for purifying radioactive iodine and aerosols, Features: It includes a device shell, an electrostatic purification chamber, a high-voltage generating system, a spray flushing system and an ozone supply system. The device shell is provided with an exhaust gas inlet and an exhaust gas outlet. The electrostatic purification chamber is arranged in the device shell. The exhaust gas inlet is connected to a first side of the ozone supply system. The second side of the ozone supply system is connected to a first side of the high-voltage generating system. The second side of the high-voltage generating system is connected to the exhaust gas outlet. The lower side of the spray flushing system is located at the lower side of the electrostatic purification chamber. The upper side of the spray flushing system extends to the upper side of the inner cylinder of the electrostatic purification chamber. The ozone supply system is used to generate a certain concentration of ozone, which, after mixing with the airflow, oxidizes the radioactive iodine in the airflow into aerosol particles containing iodine oxide; The high voltage generating system is used to generate a high voltage electrostatic field inside the electrostatic purification chamber to charge the aerosol particles in the airflow, so that the aerosol particles are affected by the electric field force and are collected on the cylinder wall of the electrostatic purification chamber; The spray flushing system is used to extract alkali solution of a certain concentration to flush the cylinder wall of the electrostatic purification chamber, so as to clean the aerosol particles adsorbed on the cylinder wall in the solution pool of the spray flushing system.

2. A radioactive iodine and aerosol purification device according to claim 1, Features: The spray flushing system includes a fine water filter and a circulating water pump. The solution in the solution pool is circulated and purified through the filter to fix the aerosol particles in the air flow in the filter. The purified alkali solution can be sprayed again through the high-pressure circulating pump.

3. A radioactive iodine and aerosol purification device according to claim 1, Features: The device also includes a water mist generating system, which is arranged between the exhaust gas inlet and the ozone supply system. The water mist generated by the water mist generating system enters the purification device along with the air flow through the Venturi structure on the water mist diffusion chamber.

4. A radioactive iodine and aerosol purification device according to claim 3, Features: The water mist generating system extracts the solution in the solution pool to generate water mist.

5. A radioactive iodine and aerosol purification device according to claim 1, Features: The device also includes a cooling circulation system, which is arranged at the top of the electrostatic purification chamber, and the cooling circulation system is arranged between the high-voltage generating system and the exhaust gas outlet. The cooling circulation system is used to cool the inner cylinder of the electrostatic purification chamber to reduce the air flow temperature.

6. A radioactive iodine and aerosol purification device according to claim 1, Features: The device also includes an air-water separation system, which is arranged before the exhaust gas outlet. The air-water separation system removes moisture from the airflow by using the centrifugal force of the rotary blades under the support of the blade bearing.

7. A radioactive iodine and aerosol purification device according to claim 2, Features: The filter is replaceable, the solution nozzle of the spray flushing system is located above the inner cylinder of the electrostatic purification room, the spray liquid sprayed by the solution nozzle can 100% cover the inner cylinder range of the electrostatic purification room, and the spray flushing system can choose to spray alkali solution or water by switching the valve.

8. A radioactive iodine and aerosol purification device according to claim 7, Features: The alkali solution includes NaOH solution.

9. A radioactive iodine and aerosol purification device according to claim 1, Features: The connecting cables of the high voltage generating system are sealed using penetration seals.

10. A radioactive iodine and aerosol purification device according to claim 5, Features: The cooling circulation system comprises a heat dissipation circuit, a circulation pump, a cooling medium and a coolant coil, and the coolant coil is spiral.

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