A radioactive decontamination system for a pressurized water reactor nuclear power plant and its process layout structure

Abstract

The present invention relates to a radioactive decontamination system for a pressurized water reactor nuclear power plant and its process layout structure. The decontamination system and its process layout structure provided by the present invention are adopted, and by reasonably arranging the various decontamination equipment and decontamination waste liquid collection equipment provided by the decontamination system in the decontamination workshop, the process layout structure of the decontamination workshop where the decontamination system is located is simple in form, occupies a small space, has high decontamination operation efficiency, is simple and convenient to operate, and can be remotely controlled. At the same time, the decontamination equipment in the decontamination system provided by the present invention is novel, and the discharge volume of decontamination waste liquid is small, which ensures the safety of the operator, is conducive to the collection and treatment of decontamination waste liquid, and also improves the storage and treatment capacity of the waste liquid. In addition, the process layout structure provided by the present invention also simplifies the number of pipelines and cables, so that the entire decontamination system and its supporting facilities are arranged to achieve the most optimized design as much as possible.

Description

Technical Field

[0001] The invention belongs to the technical field of radioactive in-service decontamination in the field of nuclear power, and in particular relates to a radioactive decontamination system for a pressurized water reactor nuclear power plant and a process arrangement structure thereof. Background Art

[0002] At present, PWR nuclear power plants need to inspect and repair systems and equipment during shutdowns and refueling. Since most of the equipment removed from the nuclear island for repair is radioactively contaminated, it is necessary to design a decontamination system and a reasonable layout structure of the decontamination workshop where it is located to decontaminate the main equipment or system components before maintenance. After decontamination, the radioactivity level of the equipment drops to a level acceptable to maintenance personnel.

[0003] At present, the design of domestic decontamination workshops generally follows the equipment and layout of Daya Bay Nuclear Power Plant. Due to the upgrading of reactor types and equipment in nuclear power plants under construction, many decontamination facilities and layout plans can no longer meet the needs of existing decontamination processes. There are many problems in space layout, equipment use, process design, safe and convenient operation of personnel, and waste liquid discharge. The optimized layout of the decontamination system and the decontamination workshop where it is located must not only meet the requirements of the decontamination process, but also ensure the safety and convenience of personnel operation. At the same time, the layout of the decontamination equipment must also ensure the reliability and high efficiency of the decontamination work, and try to adopt a simple, reliable, easy-to-maintain, and less-interference layout plan to achieve the optimization of equipment configuration and layout, and improve safety and economy. Summary of the invention

[0004] In view of the problems existing in the existing radioactive decontamination systems and their process layouts, the purpose of the present invention is to provide a radioactive decontamination system for a pressurized water reactor nuclear power plant and its process layout structure, through which radioactively contaminated equipment or components can be decontaminated in a safer, more reliable, practical and efficient manner, and the economy of the workshop and system layout can be improved, making the entire decontamination system more environmentally friendly and energy-saving.

[0005] In order to achieve the above-mentioned purpose of the invention, the present invention provides a radioactive decontamination system for a pressurized water reactor nuclear power plant, including a disassembly and cleaning table, a multifunctional decontamination chamber facility, a centralized control console, an ultrasonic generator module, a main pump decontamination facility, a reagent preparation module, an integrated decontamination device, a long workpiece decontamination box, an eyewash station, a small decontamination platform, a heater, a decontamination solution sampling module, a decontamination waste liquid collection facility, and connecting pipes and valve accessories between each module, device, and facility.

[0006] Furthermore, the process layout structure of the decontamination system is as follows: the decontamination system is mainly arranged in the ultrasonic control room, reagent preparation room, decontamination area, multifunctional decontamination room and decontamination waste liquid collection room of the decontamination workshop; wherein the ultrasonic control room and reagent preparation room are both arranged on one side of the decontamination area and arranged adjacently; the decontamination waste liquid collection room is arranged below the decontamination area;

[0007] The control console and ultrasonic generator module are arranged in the ultrasonic control room as a control center for remote operation of personnel; except for the disassembly and cleaning table and the small decontamination platform, other decontamination equipment are connected to the control console through cables and / or communication networks and transmit signals to realize remote monitoring operation.

[0008] Further, the ultrasonic generator module includes a main pump decontamination facility ultrasonic generator, an integrated decontamination device ultrasonic generator, and a long workpiece decontamination box ultrasonic generator;

[0009] The decontamination waste liquid collection facility includes a chemical waste liquid pretreatment device, a delivery pump, and a waste liquid drain tank arranged in the decontamination waste liquid collection chamber; wherein the delivery pump includes a delivery pump A and a delivery pump B, and the waste liquid drain tank includes a mechanical waste liquid drain tank A, a mechanical waste liquid drain tank B, a mechanical waste liquid drain tank C, a chemical waste liquid drain tank A, and a chemical waste liquid drain tank B.

[0010] Furthermore, the main pump decontamination facility, reagent preparation module, integrated decontamination device, decontamination solution sampling module and chemical waste liquid pretreatment device are all modularly designed and installed combination modules, and the combination modules include corresponding equipment, pipelines, valves, instruments, and supporting structures. Each module in the combination module is assembled and debugged in the factory, and the connection and positioning between modules are completed after being transported as a whole to the decontamination workshop of the nuclear power plant.

[0011] Furthermore, the integrated decontamination device realizes the combined decontamination function of multiple individual decontamination facilities constituting the integrated decontamination device, and is equipped with independent transmission, hoisting positioning, decontamination, cleaning, drying and dosage detection functions, completing a streamlined one-stop decontamination operation;

[0012] The main monitoring parameters of the integrated decontamination device are monitored in real time on the centralized control console, and the main monitoring parameters include temperature, liquid level, surface dose rate, and operating status.

[0013] Furthermore, the multifunctional decontamination chamber is an independent sealed decontamination unit, which is provided with a separate control room, radiation-proof glass for monitoring, an airtight sliding door, an operating glove hole, a movable decontamination operating table, a manipulator operating system, an exhaust gas filtration and emission device, and equipment interfaces for dry ice decontamination and laser decontamination. The decontamination equipment is placed on the movable decontamination operating table for decontamination. A slide rail is provided at the bottom of the movable decontamination operating table, and the movable decontamination operating table can be moved on the slide rail; the operating status signal of the exhaust gas filtration and emission device is sent to the control room for monitoring.

[0014] Furthermore, the physical decontamination equipment is dispersedly arranged in different areas of the decontamination workshop, and the physical decontamination equipment includes a disassembly and cleaning table, a multifunctional decontamination chamber facility, and a small decontamination platform; wherein the disassembly and cleaning table and the small decontamination platform are surrounded by at least two concrete walls, and the disassembly and cleaning table and the small decontamination platform do not interfere with each other during operation;

[0015] The chemical decontamination equipment is arranged adjacent to each other in the decontamination area, and the chemical decontamination equipment includes a main pump decontamination facility, an integrated decontamination device, and a long workpiece decontamination box; the chemical decontamination equipment is adjacent to the ultrasonic control room to reduce the length of the ultrasonic cable arrangement; the chemical decontamination equipment is arranged adjacent to the reagent preparation room to reduce the transportation path and arrangement length of the chemical decontamination liquid pipeline; only a personnel passage path, maintenance space or partition wall is left between the chemical decontamination equipment;

[0016] A steel platform is arranged below the integrated decontamination device and the long workpiece decontamination box, and all cables and pipelines are arranged below the steel platform, which does not affect the decontamination operation and ensures the safety of personnel. All operating valves are arranged above the steel platform at a position that is easily accessible to personnel.

[0017] Furthermore, the mechanical waste liquid drain tank A, mechanical waste liquid drain tank B, and mechanical waste liquid drain tank C discharge the waste liquid into the corresponding waste liquid treatment system or directly discharge it through the delivery pump A; the chemical waste liquid drain tank A and chemical waste liquid drain tank B discharge the waste liquid into the corresponding waste liquid treatment system through the delivery pump B;

[0018] The mechanical waste liquid drain tank A, mechanical waste liquid drain tank B, mechanical waste liquid drain tank C and the chemical waste liquid drain tank A, chemical waste liquid drain tank B are cylindrical vertical containers with the same structure and the same volume; the mechanical waste liquid drain tank A, mechanical waste liquid drain tank B, mechanical waste liquid drain tank C are connected through an overflow port, and the chemical waste liquid drain tank A and chemical waste liquid drain tank B are connected through an overflow port;

[0019] The waste liquid drain tanks are all equipped with liquid level transmitters, and are equipped with high liquid level interlock alarm switches, high-high liquid level interlock alarm switches, low liquid level interlock alarm switches, and low-low liquid level interlock alarm switches;

[0020] The mechanical waste liquid drain tank A is provided with two discharge outlets, which flow to the delivery pump A and the delivery pump B respectively.

[0021] Furthermore, the chemical waste liquid pretreatment device mainly uses membrane treatment technology to pretreat the chemical waste liquid to meet the discharge requirements;

[0022] The chemical waste liquid pretreatment device is connected to the mechanical waste liquid drain tank A, mechanical waste liquid drain tank B, mechanical waste liquid drain tank C or chemical waste liquid drain tank A, chemical waste liquid drain tank B through a flexible connection device to filter and adsorb the decontaminated waste liquid therein; the treatment capacity of the chemical waste liquid pretreatment device is not less than 1m 3 / h, the decomposition rate of organic matter is greater than 90%, and the radioactivity is less than 50Bq / L.

[0023] Furthermore, all decontamination equipment discharges waste liquid into the mechanical waste liquid drain tank A, mechanical waste liquid drain tank B, mechanical waste liquid drain tank C or chemical waste liquid drain tank A, chemical waste liquid drain tank B through gravity; wherein, the waste liquid from the disassembly and cleaning table, multi-functional decontamination chamber, eyewash station, and small decontamination platform is discharged into the mechanical waste liquid drain tank A, mechanical waste liquid drain tank B, and mechanical waste liquid drain tank C, and the waste liquid first enters the mechanical waste liquid drain tank C, and then enters the mechanical waste liquid drain tank B and mechanical waste liquid drain tank A in sequence; the waste liquid from the main pump decontamination facility, reagent preparation module, integrated decontamination device, and long workpiece decontamination tank is discharged into the chemical waste liquid drain tank A and chemical waste liquid drain tank B; the waste liquid first enters the chemical waste liquid drain tank A, and then enters the chemical waste liquid drain tank B.

[0024] Furthermore, when the chemical waste liquid drain tank A and the chemical waste liquid drain tank B are full, the high liquid level interlock alarm switch alarms, and the waste liquid of the main pump decontamination facility is discharged into the mechanical waste liquid drain tank A.

[0025] The beneficial effect of the present invention is that the radioactive decontamination system of a pressurized water reactor nuclear power plant provided by the present invention and its process layout structure are reasonably arranged in the multifunctional decontamination chamber, ultrasonic control room, reagent preparation room, ultrasonic generator module, main pump decontamination facility, reagent preparation module, integrated decontamination device, long workpiece decontamination box, eyewash, small decontamination platform, heater, decontamination solution sampling module, and decontamination waste liquid collection facility. The process layout structure of the decontamination workshop where the decontamination system is located is simple, occupies a small space, has high decontamination operation efficiency, is simple and convenient to operate, and can be remotely controlled. At the same time, the decontamination equipment provided by the present invention is novel, the decontamination waste liquid discharge is small, the safety of the operator is guaranteed, it is conducive to the collection and treatment of the decontamination waste liquid, and the storage and treatment capacity of the waste liquid is improved. In addition, the arrangement of each decontamination equipment in the decontamination system provided by the present invention is guided by the decontamination process flow, taking into account the unity of regional functions. The decontamination equipment adopts modular design and manufacturing, which saves layout space and transportation routes, reduces the workload of on-site installation and commissioning, and simplifies the number of pipes and cables, so that the entire decontamination system and its supporting facilities can be optimally designed. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The figure is a schematic diagram of the arrangement structure of the radioactive decontamination system of the present invention in a decontamination workshop.

[0027] Figure 2 This is a layout diagram of the decontamination waste liquid collection facilities in the decontamination waste liquid collection chamber of the present invention.

[0028] Figure 3 This is a schematic diagram of the main process flow of the radioactive decontamination system of the present invention. DETAILED DESCRIPTION

[0029] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0030] like Figures 1 to 3 As shown, this embodiment provides a radioactive decontamination system for a pressurized water reactor nuclear power plant, including a disassembly and cleaning table 101, a multifunctional decontamination chamber facility, a centralized control table 3, an ultrasonic generator module, a main pump decontamination facility 5, a reagent preparation module 601, an integrated decontamination device 7, a long workpiece decontamination box 8, an eyewash station 9, a small decontamination platform 102, a heater 10, a decontamination solution sampling module 11, a decontamination waste liquid collection facility and its connected pipes and valves and other accessories.

[0031] The multifunctional decontamination chamber facility includes a control room 201 arranged in the multifunctional decontamination chamber 2, radiation-proof glass 202, a movable decontamination operating table 203, a robot operating system 204, an exhaust gas filtering and exhausting device 205, a slide rail 206, an operating glove hole 207, and an airtight sliding door 208.

[0032] The ultrasonic generator module includes a main pump decontamination facility ultrasonic generator 401, an integrated decontamination device ultrasonic generator 402, and a long workpiece decontamination box ultrasonic generator 403.

[0033] The above-mentioned various decontamination devices, equipment and facilities are all modularly designed, manufactured and assembled, and have decontamination functions that can be used independently. They can be used as independent decontamination units or in combination.

[0034] The main pump decontamination facility 5, the reagent preparation module 601, the integrated decontamination device 7 and the decontamination solution sampling module 11 are all modularly designed and installed combination modules, which include corresponding equipment, pipelines, valves, instruments, supporting structures, etc. Each module in the combination module is assembled and debugged in the factory and can be used separately. After being transported as a whole to the decontamination workshop of the nuclear power plant, the connection and positioning between the modules are completed.

[0035] The decontamination waste liquid collection facility includes a chemical waste liquid pretreatment device 131, a delivery pump, and a waste liquid drain tank arranged in the decontamination waste liquid collection chamber 13; wherein the delivery pump includes a delivery pump A132 and a delivery pump B136, and the waste liquid drain tank includes a mechanical waste liquid drain tank A133, a mechanical waste liquid drain tank B134, a mechanical waste liquid drain tank C135, a chemical waste liquid drain tank A137, and a chemical waste liquid drain tank B138. The mechanical waste liquid drain tank A133, the mechanical waste liquid drain tank B134, the mechanical waste liquid drain tank C135, the chemical waste liquid drain tank A137, and the chemical waste liquid drain tank B138 are cylindrical vertical containers with the same structure and the same volume (the effective volume of each drain tank is not less than 8.5m 3 ) and press Figure 2 The mechanical waste liquid drain tank A133, mechanical waste liquid drain tank B134, and mechanical waste liquid drain tank C135 discharge waste liquid into the corresponding waste liquid treatment system or directly through the delivery pump A132; the chemical waste liquid drain tank A137 and chemical waste liquid drain tank B138 discharge waste liquid into the corresponding waste liquid treatment system through the delivery pump B136. In this embodiment, the mechanical waste liquid drain tank A133 is provided with two discharge outlets, which flow to the delivery pump A132 and the delivery pump B136 respectively.

[0036] The chemical waste liquid pretreatment device 131 is modularly designed and installed. The modules include equipment, pipelines, valves, instruments, supporting structures, etc. They are assembled and debugged in the factory and can be used separately. The module is positioned after being transported as a whole to the decontaminated waste liquid collection room 13 of the nuclear power plant. This module can be connected to the mechanical waste liquid drain tank A133, mechanical waste liquid drain tank B134, mechanical waste liquid drain tank C135 or chemical waste liquid drain tank A137, chemical waste liquid drain tank B138 through a flexible connection device as needed to filter and adsorb the decontaminated waste liquid therein. The treatment capacity of the chemical waste liquid pretreatment device 131 is not less than 1m 3 / h, the decomposition rate of organic matter is greater than 90%, and the radioactivity is less than 50Bq / L.

[0037] like Figures 1 to 3 As shown, this embodiment also provides a process layout structure of a radioactive decontamination system for a pressurized water reactor nuclear power plant, wherein the decontamination system is reasonably arranged in a multifunctional decontamination chamber 2, an ultrasonic control chamber 4, a reagent preparation room 6, a decontamination area 1 and a decontamination waste liquid collection chamber 13. The decontamination workshop where the decontamination system is located is mainly divided into a radiation control area 12 (about 30m 2 )、Ultrasonic control area 4 (about 28m 2 )、Reagent preparation room 6 (about 22m 2 )、Decontamination Area 1 (about 350m 2 )、Multi-function decontamination chamber 2 (about 40m 2 ), the decontamination waste liquid collection chamber 13 is arranged below the decontamination area; each area is Figure 1 The total construction area of ​​the entire decontamination workshop does not exceed 470m 2 The ultrasonic control room 4 and the reagent preparation room 6 are both arranged on one side of the decontamination area 1 and are arranged adjacent to each other; the control console 3 and the ultrasonic generator module are arranged in the ultrasonic control room 4 as a control center for remote operation of personnel; except for the disassembly and cleaning table 101 and the small decontamination platform 102, other decontamination equipment are connected to the control console 3 through cables or communication networks and transmit signals to realize remote monitoring and operation.

[0038] According to different decontamination methods, the physical decontamination equipment (disassembly and cleaning table 101, multifunctional decontamination chamber facilities, small decontamination platform 102) are dispersed in different areas of the decontamination workshop. Among them, the disassembly and cleaning table 101 and the small decontamination platform 102 are surrounded by at least two concrete walls and are far apart so that they do not interfere with each other during operation. The chemical decontamination equipment (main pump decontamination facility 5, integrated decontamination device 7, long workpiece decontamination box 8) is dispersed in different areas of the decontamination workshop. Figure 1 The positions shown are arranged adjacently in the decontamination area 1, and only a personnel passage, necessary maintenance space or partition wall are left between the chemical decontamination equipment.

[0039] The multifunctional decontamination chamber 2 is an independent sealed decontamination unit with a separate control room 201. Personnel can monitor through the radiation-proof glass 202 in the independent control room 201. The control room 201 can observe the movable decontamination operation table 203 and the manipulator operation system 204 through the light-transmitting radiation-proof glass 202; the equipment interface of dry ice decontamination and laser decontamination is reserved in the chamber, and the decontamination equipment is placed on the movable decontamination operation table 203 for decontamination. A manipulator operation system 204 and an independent exhaust gas filtering and exhausting device 205 are provided. Personnel can complete decontamination in a fully automatic manner through the manipulator operation system 204 in the control room 201. The movable decontamination operation table 203 can be moved on the slide rail 206 provided at its lower part, and personnel can also perform manual operation on the movable decontamination operation table 203 through the operating glove hole 207 on the wall. By adopting the airtight sliding door 208 structure, the entire multifunctional decontamination chamber 2 is kept in a dry and sealed environment, and basically no waste liquid is generated during the decontamination process. The independently configured waste gas filtering and discharging device 205 can discharge the waste gas after treatment into the pipeline of the decontamination ventilation system. The operation status signal of the waste gas filtering and discharging device 205 can be sent to the control room 201 for monitoring.

[0040] like Figure 1 As shown, the integrated decontamination device 7 and the long workpiece decontamination box 8 are arranged adjacent to each other, a passage for personnel inspection and on-site operation is set in the middle, and a steel platform 801 is set below. All cables and pipelines are arranged below the steel platform 801, which does not affect the decontamination operation and ensures the safety of personnel. All operating valves are set at positions above the steel platform 801 that are easily accessible to personnel. The integrated decontamination device 7 can realize the joint decontamination function of multiple single decontamination facilities that constitute the integrated decontamination device, and is equipped with independent transmission, hoisting positioning, decontamination, cleaning, drying and dosage detection functions to complete the process-based one-stop decontamination operation. The main monitoring parameters (temperature, liquid level, radioactive activity, operating status) can be monitored in real time on the centralized control console 3.

[0041] The main pump decontamination facility 5, the integrated decontamination device 7 and the long workpiece decontamination box 8 are all arranged adjacent to each other and adjacent to the ultrasonic control room 4, which reduces the length of the ultrasonic cable arrangement. The chemical decontamination facility (mainly including the main pump decontamination facility 5, the integrated decontamination device 7 and the long workpiece decontamination box 8) is arranged adjacent to the reagent preparation room 6, which reduces the transportation path and arrangement length of the chemical decontamination liquid pipeline.

[0042] like Figure 1As shown, a layout structure of a radioactive decontamination system for a pressurized water reactor nuclear power plant, wherein a centralized control console 3, a main pump decontamination facility ultrasonic generator 401, an integrated decontamination device ultrasonic generator 402, and a long workpiece decontamination box ultrasonic generator 403 are arranged in an ultrasonic control room 4 on the ground floor, serving as a centralized control unit for the entire decontamination system; during the decontamination operation, personnel only need to monitor in the ultrasonic control room 4, and do not need to stay around the decontamination equipment.

[0043] The reagent preparation module 601 (one set of acid and alkali solution each) is separately arranged in the reagent preparation room 6 and requires human operation; an eyewash 9 is provided in the reagent preparation room 6, and if the reagent accidentally splashes into the operator's eyes during operation, the eyewash operation can be performed in time; the reagent preparation room 6 is adjacent to the ultrasonic control room 4, and the liquid level signal of the reagent preparation module 601 is sent to the control console 3 for display. The control console 3 can also control the start and stop of the dosing pump (on the reagent preparation module 601) to complete the online addition of the detergent.

[0044] The disassembly and cleaning station 101 and the small decontamination platform 102 are both used for surface decontamination and disassembly of equipment with low radioactivity levels. The two devices have similar functions and are suitable for equipment to be decontaminated of different sizes. Due to the relatively high frequency of use, the two devices are arranged in different areas of the decontamination area 1 to avoid mutual interference and cross contamination during use. Both devices have two adjacent walls to improve the effect of radiation protection, and the disassembly and cleaning station 101 is adjacent to the radiation control area 12. After the equipment is decontaminated, it can be placed in the radiation control area 12 nearby to prevent secondary contamination, and the transportation path is also minimized. At the same time, an eyewash 9 is provided in the decontamination area 1. If the reagent accidentally splashes into the operator's eyes during the operation, the eyewash operation can be performed in time.

[0045] The main pump decontamination facility 5 is used less frequently and is specifically used for decontamination of the hydraulic components of the reactor coolant pump (hereinafter referred to as the main pump); it has many supporting facilities for decontamination, and the decontamination area is large, requiring a certain amount of site space. In addition, since the main pump hydraulic components need to be transported with shielding containers, transportation is difficult, so the transportation path needs to be shortened as much as possible. Based on the above factors, the main pump decontamination facility 5 is arranged at the entrance of the decontamination area 1, close to the transportation channel and adjacent to the walls on both sides, which not only improves the effect of radiation protection, but also provides structural support for the arrangement of pipelines and valves. A shielding container storage area 501 is also arranged on the right side of the main pump decontamination facility 5 to temporarily store the shielding containers after decontamination.

[0046] The integrated decontamination device 7 and the long workpiece decontamination box 8 are arranged in a relatively independent area below the main pump decontamination facility 5 in the decontamination area 1. Both of these devices are universal chemical decontamination units, with similar decontamination processes to the main pump decontamination facility 5, and are equipped with ultrasonic assisted decontamination devices, but they are used more frequently than the main pump decontamination facility 5. Since the decontamination can be monitored by the remote control console 3, the two devices are concentrated in a relatively independent area in terms of layout, and a steel platform 801 is laid. Personnel can work on the steel platform 801 before and after decontamination. All pipelines and cables are arranged under the steel platform 801 to avoid contact between personnel and equipment and pipelines. In addition, the main pump decontamination facility 5, the integrated decontamination device 7 and the long workpiece decontamination box 8 are all adjacent to the ultrasonic control room 4 and the reagent preparation room 6, so that the layout of pipelines and cables is minimized, saving a lot of space and materials.

[0047] As attached Figure 2 As shown, this embodiment provides a process layout structure of a decontamination waste liquid collection chamber 13 for a radioactive decontamination workshop. Mechanical waste liquid drain tank A133, mechanical waste liquid drain tank B134, mechanical waste liquid drain tank C135 and chemical waste liquid drain tank A137, chemical waste liquid drain tank B138 adopt the same structural form, adopting a two-row arrangement scheme, each row is equipped with a delivery pump, the overflow ports between the mechanical waste liquid drain tank A133, mechanical waste liquid drain tank B134, and mechanical waste liquid drain tank C135 can be connected, and similarly, the overflow ports between the chemical waste liquid drain tank A137 and chemical waste liquid drain tank B138 are also connected.

[0048] The waste liquid drain tanks are all equipped with liquid level transmitters, and are configured with high liquid level interlock alarm switches, high-high liquid level interlock alarm switches, low liquid level interlock alarm switches, and low-low liquid level interlock alarm switches; when different types of decontamination waste liquid are discharged, the number of waste liquid drain tanks to be used can be selected according to the amount of different types of decontamination waste liquid. This layout scheme not only increases the temporary storage capacity of waste liquid, but also saves layout space, and can more conveniently monitor the waste liquid discharge volume, thereby speeding up the discharge and treatment speed.

[0049] The mechanical waste liquid drain tank A133, mechanical waste liquid drain tank B134, mechanical waste liquid drain tank C135 and chemical waste liquid drain tank A137, chemical waste liquid drain tank B138 in the decontamination waste liquid collection chamber 13 are completely the same in structure, all of which are arranged vertically and connected to each other by pipes, which can reduce the equipment design and manufacturing costs and meet the needs of temporary storage and discharge of waste liquid. Sampling interfaces are set on all waste liquid drain tanks, and manual sampling can be used to measure the radioactive activity of waste liquid. Delivery pump A132 and delivery pump B136 can not only discharge waste liquid, but also be used for mixing and stirring waste liquid.

[0050] A chemical waste liquid pretreatment device 131 is also provided in the decontamination waste liquid collection chamber 13. The chemical waste liquid pretreatment device 131 is a modular movable facility that mainly uses membrane treatment technology to pretreat chemical waste liquid to meet discharge requirements. When necessary, the waste liquid collection system is connected to pre-filter and degrade organic matter and macromolecular chemicals in the waste liquid to further reduce the radioactivity and salt content of the waste liquid. The chemical waste liquid pretreatment device 131 can be connected to the chemical waste liquid drain tank A137 through a flexible connecting pipe according to the sampling results, completing the rapid assembly and commissioning of temporary pretreatment facilities.

[0051] All decontamination equipment discharges waste liquid into the waste liquid drain tank by gravity, among which the waste liquid from the disassembly and cleaning table 101, the multifunctional decontamination chamber 2, the eyewash 9, and the small decontamination platform 102 can be discharged into the mechanical waste liquid drain tank A133, the mechanical waste liquid drain tank B134, and the mechanical waste liquid drain tank C135, and the waste liquid from the main pump decontamination facility 5, the reagent preparation module 6, the integrated decontamination device 7, and the long workpiece decontamination tank 8 can be discharged into the chemical waste liquid drain tank A137 and the chemical waste liquid drain tank B138. In this embodiment, when the chemical waste liquid drain tank A137 and the chemical waste liquid drain tank B138 are full, the high liquid level interlock alarm switch alarms, and the waste liquid from the main pump decontamination facility 5 can also be discharged into the mechanical waste liquid drain tank A133.

[0052] Mechanical waste liquid drain tank A133, mechanical waste liquid drain tank B134, and mechanical waste liquid drain tank C135 are connected by an overflow port, and the waste liquid discharged into the mechanical waste liquid drain tank first enters the mechanical waste liquid drain tank C135, and then enters the mechanical waste liquid drain tank B134 and mechanical waste liquid drain tank A133 in sequence; similarly, chemical waste liquid drain tank A137 and chemical waste liquid drain tank B138 are connected by an overflow port, and the waste liquid discharged into the chemical waste liquid drain tank first enters the chemical waste liquid drain tank A137, and then enters the chemical waste liquid drain tank B138.

[0053] As attached Figure 3As shown, the embodiment of the present invention provides a process layout structure of a decontamination system. The reagent preparation module 601 (one set of acid and alkali solution) is configured with acidic or alkaline decontamination liquid, which is distributed to each decontamination facility through a dosing pump and a pipeline; the desalted water is distributed to each decontamination facility through a main pipe entering the decontamination workshop. The main pipe is provided with a flow meter and a heater 10 branch. In some chemical decontamination processes, the desalted water needs to be preheated to shorten the heating time during water replenishment. The multifunctional decontamination chamber 2 is provided with an interface for dry ice and a laser decontamination device, which is generally a dry and sealed environment. If there is a small amount of waste liquid, it can be directly discharged into the mechanical waste liquid drain tank. The waste liquid of the chemical decontamination facility needs to be discharged separately to the chemical waste liquid drain tank. In particular, since the main pump decontamination facility 5 in this embodiment adopts an oxidation-reduction method for decontamination, the amount of waste liquid is large. When the chemical waste liquid drain tank has no capacity, it can be discharged to the mechanical waste liquid drain tank A133 according to the situation, and the delivery pump B136 can be neutralized and stirred to reduce the salt content in the waste liquid.

[0054] The above embodiments are merely illustrative of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A radioactive decontamination system for a pressurized water reactor nuclear power plant, characterized in that: It includes a disassembly and cleaning table (101), a multifunctional decontamination chamber facility, a centralized control table (3), an ultrasonic generator module, a main pump decontamination facility (5), a reagent preparation module (601), an integrated decontamination device (7), a long workpiece decontamination box (8), an eyewash station (9), a small decontamination platform (102), a heater (10), a decontamination solution sampling module (11), a decontamination waste liquid collection facility, and connecting pipes and valve accessories between the modules, devices, and facilities; The process layout structure of the decontamination system is as follows: the decontamination system is mainly arranged in the ultrasonic control room (4), the reagent preparation room (6), the decontamination area (1), the multifunctional decontamination room (2) and the decontamination waste liquid collection room (13) of the decontamination workshop; wherein the ultrasonic control room (4) and the reagent preparation room (6) are both arranged on one side of the decontamination area (1) and arranged adjacently; the decontamination waste liquid collection room (13) is arranged below the decontamination area (1); The centralized control station (3) and the ultrasonic generator module are arranged in the ultrasonic control room (4) as a control center for remote operation by personnel; except for the disassembly and cleaning table (101) and the small decontamination platform (102), other decontamination equipment are connected to the centralized control station (3) through cables and / or communication networks and transmit signals to realize remote monitoring operation; The chemical decontamination equipment is arranged adjacent to each other in the decontamination area (1), and the chemical decontamination equipment includes a main pump decontamination facility (5), an integrated decontamination device (7), and a long workpiece decontamination box (8); the chemical decontamination equipment is adjacent to the ultrasonic control room (4) to reduce the length of the ultrasonic cable arrangement; the chemical decontamination equipment is arranged adjacent to the reagent preparation room (6) to reduce the transportation path and arrangement length of the chemical decontamination liquid pipeline; only a personnel passage path, maintenance space or partition wall is reserved between the chemical decontamination equipment; The decontamination waste liquid collection facility comprises a chemical waste liquid pretreatment device (131), a delivery pump, and a waste liquid drain tank arranged in the decontamination waste liquid collection chamber (13); the chemical waste liquid pretreatment device (131) mainly uses membrane treatment technology to pre-treat the chemical waste liquid to meet the discharge requirements; when necessary, it is connected to the waste liquid collection system to pre-filter and degrade organic matter and macromolecular chemical substances in the waste liquid, thereby further reducing the radioactivity and salt content of the waste liquid; All decontamination equipment discharges waste liquid into the waste liquid drain tank by gravity.

2. A radioactive decontamination system for a pressurized water reactor nuclear power plant according to claim 1, characterized in that: The ultrasonic generator module comprises a main pump decontamination facility ultrasonic generator (401), an integrated decontamination device ultrasonic generator (402), and a long workpiece decontamination box ultrasonic generator (403); The delivery pump includes a delivery pump A (132) and a delivery pump B (136), and the waste liquid drain tank includes a mechanical waste liquid drain tank A (133), a mechanical waste liquid drain tank B (134), a mechanical waste liquid drain tank C (135), a chemical waste liquid drain tank A (137), and a chemical waste liquid drain tank B (138).

3. A radioactive decontamination system for a pressurized water reactor nuclear power plant according to claim 2, characterized in that: The main pump decontamination facility (5), reagent preparation module (601), integrated decontamination device (7), decontamination solution sampling module (11) and chemical waste liquid pretreatment device (131) are all modularly designed and installed combination modules, and the combination modules include corresponding equipment, pipelines, valves, instruments, and supporting structures. Each module in the combination module is assembled and debugged in the factory, and the connection and positioning between modules are completed after the entire module is transported to the decontamination workshop of the nuclear power plant.

4. A radioactive decontamination system for a pressurized water reactor nuclear power plant according to claim 1, characterized in that: The integrated decontamination device (7) realizes the combined decontamination function of the multiple individual decontamination facilities constituting the integrated decontamination device (7), and is equipped with independent transmission, hoisting positioning, decontamination, cleaning, drying and dosage detection functions, thereby completing a streamlined one-stop decontamination operation; The main monitoring parameters of the integrated decontamination device (7) are monitored in real time on the centralized control console (3), and the main monitoring parameters include temperature, liquid level, surface dose rate, and operating status.

5. A radioactive decontamination system for a pressurized water reactor nuclear power plant according to any one of claims 1 to 4, characterized in that: The multifunctional decontamination chamber (2) is an independent sealed decontamination unit, which is provided with a separate control room (201), radiation-proof glass (202) for monitoring, an airtight sliding door (208), an operating glove hole (207), a movable decontamination operation table (203), a manipulator operating system (204), an exhaust gas filtering and exhausting device (205), and equipment interfaces for dry ice decontamination and laser decontamination. The decontamination equipment is placed on the movable decontamination operation table (203) for decontamination. A slide rail (206) is provided at the bottom of the movable decontamination operation table (203), and the movable decontamination operation table (203) can be moved on the slide rail (206); the operating status signal of the exhaust gas filtering and exhausting device (205) is sent to the control room (201) for monitoring.

6. A radioactive decontamination system for a pressurized water reactor nuclear power plant according to claim 5, characterized in that: The physical decontamination equipment is dispersedly arranged in different areas of the decontamination workshop, and the physical decontamination equipment includes a disassembly and cleaning table (101), a multifunctional decontamination chamber facility, and a small decontamination platform (102); wherein the disassembly and cleaning table (101) and the small decontamination platform (102) are surrounded by at least two concrete walls, and the disassembly and cleaning table (101) and the small decontamination platform (102) do not interfere with each other during operation; A steel platform (801) is arranged below the integrated decontamination device (7) and the long workpiece decontamination box (8), and all cables and pipelines are arranged below the steel platform (801) so as not to affect the decontamination operation and ensure the safety of personnel. All operating valves are arranged above the steel platform (801) in a position that is easily accessible to personnel.

7. A radioactive decontamination system for a pressurized water reactor nuclear power plant according to claim 2 or 3, characterized in that: The mechanical waste liquid drain tank A (133), mechanical waste liquid drain tank B (134), and mechanical waste liquid drain tank C (135) discharge waste liquid into a corresponding waste liquid treatment system or directly discharge it through the delivery pump A (132); the chemical waste liquid drain tank A (137) and chemical waste liquid drain tank B (138) discharge waste liquid into a corresponding waste liquid treatment system through the delivery pump B (136); The mechanical waste liquid drain tank A (133), mechanical waste liquid drain tank B (134), mechanical waste liquid drain tank C (135) and the chemical waste liquid drain tank A (137), chemical waste liquid drain tank B (138) are cylindrical vertical containers with the same structure and the same volume; the mechanical waste liquid drain tank A (133), mechanical waste liquid drain tank B (134), mechanical waste liquid drain tank C (135) are connected through an overflow port, and the chemical waste liquid drain tank A (137) and chemical waste liquid drain tank B (138) are connected through an overflow port; The waste liquid drain tanks are all equipped with liquid level transmitters, and are equipped with high liquid level interlock alarm switches, high-high liquid level interlock alarm switches, low liquid level interlock alarm switches, and low-low liquid level interlock alarm switches; The mechanical waste liquid drain tank A (133) is provided with two discharge outlets, which flow to the delivery pump A (132) and the delivery pump B (136) respectively.

8. A radioactive decontamination system for a pressurized water reactor nuclear power plant according to claim 7, characterized in that: The chemical waste liquid pretreatment device (131) is connected to the mechanical waste liquid drain tank A (133), the mechanical waste liquid drain tank B (134), the mechanical waste liquid drain tank C (135) or the chemical waste liquid drain tank A (137), the chemical waste liquid drain tank B (138) through a flexible connection device to filter and adsorb the decontaminated waste liquid therein; the treatment capacity of the chemical waste liquid pretreatment device (131) is not less than 1m 3 / h, the decomposition rate of organic matter is greater than 90%, and the radioactivity is less than 50Bq / L.

9. A radioactive decontamination system for a pressurized water reactor nuclear power plant according to claim 7, characterized in that: All decontamination equipment discharges waste liquid into the mechanical waste liquid drain tank A (133), mechanical waste liquid drain tank B (134), mechanical waste liquid drain tank C (135) or chemical waste liquid drain tank A (137), chemical waste liquid drain tank B (138) by gravity; wherein the waste liquid of the disassembly and cleaning station (101), the multifunctional decontamination chamber (2), the eyewash station (9), and the small decontamination platform (102) is discharged into the mechanical waste liquid drain tank A (133), mechanical waste liquid drain tank B (134), mechanical waste liquid drain tank C (135) or chemical waste liquid drain tank A (137), chemical waste liquid drain tank B (138). The waste liquid first enters the mechanical waste liquid drain tank C (135), and then enters the mechanical waste liquid drain tank B (134) and the mechanical waste liquid drain tank A (133) in sequence; the waste liquid of the main pump decontamination facility (5), the reagent preparation module (601), the integrated decontamination device (7), and the long workpiece decontamination tank (8) is discharged into the chemical waste liquid drain tank A (137) and the chemical waste liquid drain tank B (138), and the waste liquid first enters the chemical waste liquid drain tank A, and then enters the chemical waste liquid drain tank B.

10. A radioactive decontamination system for a pressurized water reactor nuclear power plant according to claim 7, characterized in that: When the chemical waste liquid drain tank A (137) and the chemical waste liquid drain tank B (138) are full, the high liquid level interlock alarm switch alarms, and the waste liquid of the main pump decontamination facility (5) is discharged into the mechanical waste liquid drain tank A (133).

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