CN114951898B - Radioactive metal waste thermal cutting device and thermal cutting method - Google Patents

Abstract

The invention discloses a radioactive metal waste thermal cutting device which comprises a negative pressure station body module, a negative pressure system and a cutting and collecting module, wherein the negative pressure system is used for providing negative pressure for the negative pressure station body module and filtering particles, dust and radioactive aerosol generated by thermal cutting of radioactive metal waste, the cutting and collecting module comprises a thermal cutting device, and the negative pressure station body module is used for placing the radioactive metal waste to be cut and the thermal cutting device. According to the radioactive metal waste thermal cutting device, radioactivity is contained in the negative pressure station body through the cooperation of the negative pressure station body module and the negative pressure system, leakage cannot occur, environmental safety and personnel safety are guaranteed, the cutting efficiency is high, and the secondary waste amount is small.

Description

Thermal cutting device and thermal cutting method for radioactive metal waste

technical field

The invention belongs to the technical field of nuclear engineering, and in particular relates to a thermal cutting device and a thermal cutting method for radioactive metal waste.

Background technique

In nuclear power projects, the main radioactive large-scale nuclear island equipment such as reactor pressure vessel top cover, steam generator, and voltage stabilizer has the characteristics of large volume, heavy weight, and thick wall thickness. In order to reduce the radioactive solid waste after decommissioning The volume reduces the cost of disposal, and these devices need to be cut and reconditioned in situ when they are decommissioned.

The top cover of the reactor pressure vessel has a total weight of 58 tons, an outer diameter of 4.7 meters, and a total height of nearly 3 meters. The thickness of the head part reaches 170mm, and the thickness of the flange part reaches 850mm. The shape of the steam generator is a vertical storage tank structure, with an inner diameter of up to 1.5 meters, a wall thickness of 46mm, and a total equipment height of 6 meters. According to the decommissioning requirements of nuclear power projects, cutting equipment is required for the U-shaped tubes and some shells inside. The shape of the voltage stabilizer is a vertical storage tank structure with an inner diameter of up to 1.2 meters and a wall thickness of up to 63mm. Generally, it is cut and prepared as a whole.

At present, diamond wire saw or water jet technology is generally used to cut radioactive thick and large pieces at home and abroad. There are two disadvantages in these two processes: 1. Slow cutting speed: thermal cutting (flame cutting, plasma cutting) is 10 to 50 times faster than diamond wire saw and water jet cutting speed for thick and large pieces with the same thickness. 2. Cutting produces a large amount of secondary waste: After the diamond wire saw cuts radioactive equipment, its overall mechanical structure is polluted and turned into radioactive pollutants; the waterjet cutting process needs to add a large amount of solid abrasives to the water, and the abrasives are converted into radioactive pollutants.

Overall, the amount of secondary waste from thermal cutting (flame cutting, plasma cutting) is only about 5% of that of diamond wire saw and waterjet cutting. However, thermal cutting of radioactive thick and large pieces will produce a large number of air pollutants such as radioactive particles, radioactive dust, aerosols, etc., which will not only pollute the environment, but also threaten the safety of personnel.

Contents of the invention

In view of this, in order to overcome the defects of the prior art, the object of the present invention is to provide a thermal cutting device for radioactive metal waste, which can safely use flame cutting or plasma cutting to carry out cutting preparations for radioactive thick and large pieces, which improves cutting efficiency and reduces The amount of secondary waste is reduced, and the problem of radioactive particles, dust, and aerosols produced by thermal cutting is also solved to ensure the safety of the environment and personnel.

In order to achieve the above object, the present invention adopts the following technical solutions:

A thermal cutting device for radioactive metal waste, comprising a negative pressure station body module, a negative pressure system and a cutting collection module, the negative pressure system is used to provide negative pressure for the negative pressure station body module and to filter thermally cut radioactive metal Particles, dust and radioactive aerosol produced by waste, the cutting collection module includes a thermal cutting device, and the negative pressure station body module is used to place the radioactive metal waste to be cut and the thermal cutting device. The thermal cutting device and the radioactive metal waste to be cut are placed in the main module of the negative pressure station. The negative pressure station system provides negative pressure for the main module of the negative pressure station and absorbs the particles, dust and radioactive aerosol generated by thermal cutting. The collection module cuts and collects the radioactive metal waste to be cut.

In the above technical solution, preferably, the negative pressure station body module includes a negative pressure station body, an air intake window, a viewing window and a soft curtain, and the bottom of the negative pressure station body is provided with a traction guide rail, and the traction guide rail runs through the The negative pressure station body, the traction guide rail is provided with a collection and transport trolley, the air intake window and the viewing window are arranged on the side of the negative pressure station body, and the soft curtain is installed on the negative pressure station body for all The traction guide rail and the part where the collection transport trolley passes through. The air intake window is a shutter, and the main module of the negative pressure station is equipped with a soft curtain. On the one hand, the air intake window is used for air intake, and the soft curtain is used for the entry and exit of the traction guide rail and the collection and transportation trolley. On the other hand, it is confirmed by observation that the shutter is inward. The air intake and the soft curtain drifting inward are one of the characteristics of whether the negative pressure system is successfully activated. Specifically, when the negative pressure system is working, the louvers are opened inward to take in the wind, and the soft curtain drifts inward. When the negative pressure system is not working , the shutters and curtains are drawn shut.

In the above technical solution, it is further preferred that the body of the negative pressure station is in the shape of a cuboid, and the body of the negative pressure station includes a top cover plate and four side plates, and two adjacent side plates are bonded by a sealant , the top cover plate is also provided with lifting lugs, the negative pressure station body is provided with a thermal cutting area for cutting radioactive metal waste, the radioactive metal waste to be cut and the thermal cutting device are placed in the thermal cutting district. The main body of the negative pressure station is in the shape of a cuboid, and the surrounding side panels are made of color steel plates, and the joints are glued with sealant to ensure airtight sealing. Air intake louvers are set on the upper part of one side, and the number can be flexibly set according to the size. Recommended 2-4 For the fan, a window glass is set on the color steel plate on this side. The size depends on the actual situation. It is recommended to use no less than 1.2M×1.2M. It is used for personnel to observe the working conditions in the negative pressure station body from the outside. In addition, the negative pressure There are two lifting lugs on the top cover of the station body. When necessary, the top cover can be removed, and large items can be lifted in and out of the negative pressure station body from the top.

In the above technical solution, it is further preferred that the negative pressure system includes a main exhaust fan, a dust filter, a radioactive aerosol filter and an air outlet located outside the negative pressure station body and connected in sequence through an air duct, and located outside the negative pressure station body. The air inlet, air supply fan, exhaust fan, air suction port and a plurality of pressure gauges in the negative pressure station body, the air inlet is located at the air inlet window, and the air supply fan is used to send air to the thermal cutting area. The wind blows the particles, dust and radioactive aerosols produced by the thermal cutting of radioactive metal waste to the inlet of the exhaust fan, and the exhaust fan is used to receive the particles, dust and radioactive aerosols produced in the thermal cutting area and for Air is supplied to the air duct, and the exhaust fan and the suction port are respectively communicated with the main exhaust fan through the air duct, and the main exhaust fan is used to receive the particles, dust and radioactive particles received by the exhaust fan. Aerosol and the air in the negative pressure station body absorbed by the suction port, one of the three pressure gauges is located in the thermal cutting area, and the other two pressure gauges in the three pressure gauges The gauges are respectively close to the air inlet and the air suction port. Among them, the air supply fan and the exhaust fan jointly establish a good negative pressure space for the thermal cutting area; the air supply source of the main exhaust fan includes two parts: the air supply of the exhaust fan; absorbing the air in the negative pressure station body from the suction port; The dust filter is used to filter the particles and dust generated by thermal cutting in the ventilation system, and the radioactive aerosol filter is used to filter the radioactive aerosol in the air to ensure no radioactive leakage and ensure the external environment and personnel safety of the negative pressure station. Multiple pressure gauges are used to observe and confirm whether the readings are negative pressure, and only the main exhaust fan, supply fan, and exhaust fan are turned on; observe and confirm that the louvers are opened inward to take in air, and the soft curtains drift inward; observe and confirm the readings of each pressure gauge Negative pressure; the completion of the above three tasks indicates that negative pressure has been formed in the negative pressure workstation body.

In the above technical solution, further preferably, the negative pressure system further includes a combustible gas concentration monitor, a radiation dose monitor and a plurality of monitoring cameras arranged in the negative pressure station body. Among them, the monitoring camera is recommended to install 8 to 10 channels to ensure that the air supply fan, exhaust fan, shutter, traction guide rail, cutting device and other equipment in the negative pressure station body can be observed; the combustible gas concentration monitor is used to monitor the negative pressure station Once the concentration of the gas used for thermal cutting in the main body is detected to reach the set threshold, a concentration alarm will be triggered, and the chain cutting equipment will stop working immediately, and the gas supply pipeline will be closed; the radioactive dose monitor will continuously monitor the air in the negative pressure station. The radioactive dose radiation level is transmitted to the personnel centralized control platform in real time. Once the monitoring value exceeds the threshold, an alarm signal is issued immediately.

In the above technical solution, it is further preferred that the cutting and collecting module includes a collecting device and the thermal cutting device, and the thermal cutting device includes a gantry frame, an execution head set on the gantry frame, and a The thermal cutting head on the execution head and the supporting platform for supporting the radioactive metal waste to be cut, the gantry can move along the Y-axis direction, the execution head can shrink up and down and can move in the X-axis direction The gantry moves, and the collecting device includes the collecting and transporting trolley and the traction guide rail, and the collecting and transporting trolley is used to receive the cutting blocks of the radioactive metal waste to be cut. Among them, the executive head can realize up and down expansion and contraction, cooperate with the gantry to realize the thermal cutting head to walk in the XYZ three-axis space, and the supporting platform is used to support the parts to be cut. For large components such as parts, the thermal cutting head selects a reasonable thermal cutting process and corresponding cutting head according to the shape, thickness and material of the part to be cut.

In the above technical solution, and further preferably, the middle part of the support platform is left empty to form a discharge opening, and the cutting blocks are dropped from the discharge opening to the collecting and transporting trolley. The middle part of the support platform is left blank, and the cut material can be directly dropped to the collection and transportation trolley at the bottom. The width of the collection and transportation trolley covers the hollow area of the support platform, and the traction guide rails then pull the collection and transportation trolley to walk, and can be sent to the collection and transportation trolley Enter the main body of the negative pressure station, and the cutting material can also be transported out of the main body of the negative pressure station.

In the above technical solution, further preferably, the thermal cutting head is a flame cutting head or a plasma cutting head. Choose a reasonable thermal cutting process and cutting path according to the shape, thickness and material of the piece to be cut. Generally speaking, for carbon steel parts with a thickness of more than 60mm, flame cutting process can be selected; for stainless steel and carbon steel with a thickness of less than 60mm parts, you can choose the plasma cutting process, and then choose the thermal cutting head of the corresponding specification.

In addition, all the above equipment control systems are integrated into the centralized control platform outside the negative pressure station body to realize remote operation and control of personnel.

The present invention also provides a method for thermal cutting of radioactive metal waste, comprising the following steps:

Place the thermal cutting head and the radioactive metal waste to be cut; start the negative pressure system to form a negative pressure in the negative pressure station body; cut the radioactive metal waste to be cut, transport and collect the falling cutting pieces.

Among the above technical solutions, preferably:

Starting the negative pressure system includes the following steps: turn on the main exhaust fan, the air supply fan and the exhaust fan; observe and confirm that the air intake window opens into the negative pressure station body, and the soft curtain drifts to the inside of the negative pressure station body; observe and confirm that each The pressure gauge reads negative pressure.

Due to the adoption of the above technical solution, compared with the prior art, the present invention is beneficial in that: the radioactive metal waste thermal cutting device of the present invention, through the cooperation of the negative pressure station body module and the negative pressure system, can ensure that the radioactivity is contained in the In the negative pressure station, there will be no leakage, ensuring the safety of the environment and personnel; with the help of the video monitoring system and centralized control system, operations such as cutting and transportation can be performed remotely manually or automatically, without the need for personnel to work manually at close range, thus greatly reducing Personnel exposure to radiation dose; adapt to a variety of thermal cutting heads, can be applied to flame cutting, plasma cutting; the whole set of devices can cut radioactive thick and large pieces, including: evaporators, voltage stabilizers, reactor pressure vessel top covers and other large nuclear power equipment .

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort.

Fig. 1 is a top view of a radioactive metal waste thermal cutting device in a preferred embodiment of the present invention;

Fig. 2 is the front view of the radioactive metal waste thermal cutting device in the preferred embodiment of the present invention;

Fig. 3 is a front view of the thermal cutting device for radioactive metal waste in a preferred embodiment of the present invention (cutting the top cover of the reactor pressure vessel).

Among them: negative pressure station body-10, shutters-11, window-12, soft curtain-13, lifting lug-14, main ventilation fan-20, air duct-21, dust filter-22A, radioactive aerosol filter- 22B, monitoring camera-23, combustible gas concentration monitor-24, air supply fan-25A, exhaust fan-25B, radioactive dose monitor-26, first pressure gauge-27A, second pressure gauge-27B, third pressure Meter-27C, air outlet-28, air suction port-29, gantry-30, executive head-31, support stand-32, thermal cutting head-33, collecting and transporting trolley-34, traction guide rail-35, thermal cutting Zone-40, Reactor Pressure Vessel Head-50.

Detailed ways

In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described implementation Examples are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

Embodiment 1 A kind of thermal cutting device for radioactive metal waste

Referring to accompanying drawings 1 and 2, the radioactive metal waste thermal cutting device of this embodiment includes a negative pressure station body module, a negative pressure system and a cutting collection module. Wherein, the cutting and collecting module includes a thermal cutting device and a collecting device.

The negative pressure station body module includes a negative pressure station body 10, shutters 11, windows 12, soft curtains 13 and lifting lugs 14. The negative pressure station body 10 is a rectangular parallelepiped, including a top cover and four surrounding side panels. The negative pressure station The body 10 is provided with a thermal cutting area 40 for cutting radioactive metal waste. The radioactive metal waste to be cut and the thermal cutting device are placed in the thermal cutting area 40, wherein the body 10 of the negative pressure station is formed by splicing four colored steel plates around it. The joints between two adjacent side panels are bonded with sealant to ensure airtight sealing. Two louvers 11 are arranged on the upper side of one side panel. Of course, the number of louvers 11 can be flexibly set according to the size. Recommended 2- 4 leaves. The color steel plate on this side is provided with a window 12, the size of which depends on the actual situation. It is recommended to use no less than 1.2M×1.2M for personnel to observe the working conditions in the negative pressure station body 10 from the outside. The bottom of the negative pressure station body 10 is provided with a traction guide rail 35 that runs through, and the collection and transportation trolley 34 is installed on the traction guide rail 35. A lifting lug 14 is arranged on the top cover plate, and when necessary, it can be transferred away from the top cover plate, and large parts can be lifted in and out of the negative pressure station body 10 from the top. The negative pressure station body 10 is provided with louvers 11 and soft curtains 13. On the one hand, the louvers 11 are used for air intake, and the soft curtains 13 are used for the entry and exit of the traction guide rail 35 and the collection and transportation trolley 34. On the other hand, the orientation of the louvers 11 is confirmed by observation. Inward air intake and soft curtain 13 drifting inward are one of the characteristics of whether the negative pressure system is successfully activated. Specifically, when the negative pressure system is working, the louvers 11 are opened inward to enter the air, and the soft curtain 13 drifts inward. When the negative pressure When the system was not working, the blinds 11 and soft curtains 13 were closed down.

The negative pressure system includes: exhaust main fan 20, air duct 21, dust filter 22A, radioactive aerosol filter 22B, surveillance camera 23, combustible gas concentration monitor 24, air inlet, air supply fan 25A, exhaust fan 25B, radioactive Dose monitor 26 , first pressure gauge 27A, second pressure gauge 27B, third pressure gauge 27C, air outlet 28 , air suction outlet 29 . Wherein, the exhaust main fan 20, the dust filter 22A, the radioactive aerosol filter 22B, and the air outlet 28 are arranged outside the negative pressure station body 10 and the exhaust main fan 20, the dust filter 22A, the radioactive aerosol filter 22B, and the air outlet 28 is connected in turn through the air pipe 21, the monitoring camera 23, the combustible gas concentration monitor 24, the air inlet, the air supply fan 25A, the exhaust fan 25B, the radioactive dose monitor 26, the air suction port 29, the first pressure gauge 27A, the second pressure gauge The gauge 27B and the third pressure gauge 27C are arranged in the negative pressure station body 10 , wherein the first pressure gauge 27A is located in the thermal cutting area 40 , the second pressure gauge 27B is close to the air inlet, and the third pressure gauge 27C is close to the air suction port 29 .

The air supply fan 25A directly supplies air to the thermal cutting area 40, and the particles, dust and radioactive aerosol produced by cutting are forced to be blown to the inlet of the exhaust fan 25B, and the exhaust fan 25B receives the air supply from the air supply fan 25A and the thermal cutting area 40 produces particles, dust and radioactive aerosols, and sends air to the ventilation duct 21. The blower fan 25A and the exhaust fan 25B jointly establish a good negative pressure space for the thermal cutting zone 40 . The air supply source of the exhaust main fan 20 comprises two parts: (1) the air supply of the exhaust fan 25B; (2) absorbing the air in the negative pressure station body 10 from the suction port 29 . The dust filter 22A is used to filter particles and dust generated by thermal cutting, and the radioactive aerosol filter 22B is used to filter radioactive aerosols in the air to ensure no radioactive leakage and ensure the external environment and personnel safety of the negative pressure station. It is recommended to install 8 to 10 monitoring cameras 23 to ensure that the air supply fan 25A, exhaust fan 25B, shutters 11, traction guide rail 35, cutting device, radioactive metal waste to be cut, etc. of the negative pressure station body 10 can be observed. The combustible gas concentration monitor 24 is used to monitor the concentration of the gas used for thermal cutting in the negative pressure station body 10. Once it is detected that the concentration reaches the set threshold, a concentration alarm can be triggered, and the chain cutting equipment will stop working immediately, and the gas supply pipeline will be closed. The radioactive dose monitor 26 continuously monitors the radioactive dose radiation level in the air in the negative pressure station body 10, and transmits it to the personnel centralized control platform in real time. Once the monitored value exceeds the threshold, an alarm signal is sent immediately.

The start-up method of the negative pressure system is as follows: (1) Turn on the exhaust main fan 20, the air supply fan 25A, and the exhaust fan 25B; (2) Observe and confirm that the louver 11 is opened inward to take in the air, and the soft curtain 13 drifts inward; (3) Observe and confirm The readings of the first pressure gauge 27A, the second pressure gauge 27B and the third pressure gauge 27C are negative pressure. The completion of the above three tasks indicates that a negative pressure has been formed in the negative pressure workstation body 10. It is recommended that the pressure in the negative pressure station body 10 be lower than the atmospheric pressure by more than 3000Pa, and the air circulation times in the negative pressure station body 10 be 10 times/hour.

The cutting and collecting module includes a collecting device and a thermal cutting device. Specifically, the thermal cutting device includes a gantry 30, an execution head 31 arranged on the gantry 30, a thermal cutting head 33 arranged on the execution head 31, and a support for supporting The support stand 32 for the radioactive metal waste to be cut, and the collection device includes a collection transport trolley 34 and a traction guide rail 35 . The gantry 30 is a walking mechanism for the thermal cutting head 33 to perform cutting. The gantry 30 can move along the Y-axis direction. The execution head 31 can shrink up and down and move on the gantry 30 along the X-axis direction. The execution head 31 can Realize up and down expansion and contraction, cooperate with the gantry 30 to realize the thermal cutting head 33 walking in the XYZ three-axis space, the supporting platform 32 is used to support the parts to be cut, the recommended design load is 70 tons, and can carry large components such as round, square, and plate pieces , and the middle part of the support stand 32 is left blank, and the cut pieces of radioactive metal waste are directly dropped to the collection and transportation trolley 34 at the bottom, wherein, a reasonable thermal cutting process and a corresponding thermal cutting process are selected according to the shape, thickness, and material of the piece to be cut Thermal cutting head 33, specifically, for carbon steel parts with a thickness of more than 60mm, you can choose a flame cutting process, and then choose a flame cutting head; for stainless steel and carbon steel parts with a thickness below 60mm, you can choose a plasma cutting process, and then choose a plasma cutting head. cutting head. The collecting and transporting trolley 34 is used to accept the cut material block, and its breadth envelops the hollow area of the support stand 32, and the traction guide rail 35 pulls the collecting and transporting trolley 34 to walk, and the collecting and transporting trolley 34 can be sent into the negative pressure station body 10, and the The cutting block is transported out of the negative pressure station body 10 . All the above equipment control systems are integrated into the centralized control platform outside the negative pressure station to realize remote operation and control of personnel.

Referring to Fig. 3, it is the front view that the thermal cutting device for radioactive metal waste of the present embodiment is used to cut the reactor pressure vessel top cover 50, because the reactor pressure vessel top cover, its total weight reaches 58 tons, and outer diameter is 4.7 meters, and overall height Nearly 3 meters, the thickness of the head part reaches 170mm, and the thickness of the flange part reaches 850mm. When cutting it, the flame cutting process is selected, and then the thermal cutting head 33 selects the flame cutting head.

Embodiment 2 A kind of thermal cutting method of radioactive metal waste

This embodiment provides a thermal cutting method for radioactive metal waste according to Embodiment 1, including: placing the thermal cutting head and the radioactive metal waste to be cut; starting the negative pressure system to form a negative pressure in the negative pressure station body. Pressing; cutting radioactive metal waste to be cut, transporting and collecting falling cut pieces.

Specifically, the following steps are included:

(1) Formulate the cutting process and cutting path of radioactive metal parts: choose a reasonable thermal cutting process and cutting path according to the shape, thickness, material, etc. of the piece to be cut. Generally speaking, for carbon steel parts with a thickness of more than 60mm, you can choose flame Cutting process; for stainless steel and carbon steel parts with thickness less than 60mm, plasma cutting process can be selected.

(2) Install the corresponding thermal cutting head, set the cutting head walking program according to the path: select the thermal cutting head (flame cutting head or plasma cutting head) of the corresponding specification, install it on the executive head 31, and cut according to the preset path, the gantry 30 is set in the centralized control system and the running program of the head 31 is executed. This embodiment is used for cutting the top cover of the reactor pressure vessel, and the flame cutting head is selected to be installed on the actuator head 31 .

(3) Place the radioactive metal parts to be cut on the support platform 32: lift the radioactive metal waste to be cut (the top cover of the reactor pressure vessel in this embodiment) to the support platform 32, and lift the negative pressure station body 10 The top cover plate is in place, and the negative pressure station body 10 is closed.

(4) Start the negative pressure system to form a negative pressure in the workstation: start the negative pressure system as required, turn on the exhaust main fan 20, the air supply fan 25A, and the exhaust fan 25B; observe that the louvers 11 are opened inward to enter the air, and the soft curtain 13 is turned inward Drift; the readings of the first pressure gauge 27A, the second pressure gauge 27B, and the third pressure gauge 27C are negative pressure. Confirm that negative pressure has developed in the station.

(5) Carry out cutting according to a predetermined path: the personnel remotely operate and start the thermal cutting head 33, and operate the gantry 30 and the execution head 31 to carry out cutting according to a predetermined path.

(6) Carrying out and collecting cut and dropped cutting pieces: the bottom collecting and transporting trolley 34 undertakes the corresponding cutting pieces, and transports out the negative pressure station body 10 in good time.

The thermal cutting method of radioactive metal waste in this embodiment solves the problem of radioactive particles, dust, and aerosols, and can safely use flame cutting or plasma cutting to carry out cutting and preparation of radioactive thick and large pieces, which improves cutting efficiency and reduces secondary waste production volume.

In order to further understand the scheme of the present application, the following are illustrated with specific application implementation cases and comparative cases:

Application case: For the top cover of the reactor pressure vessel, the total weight is 58 tons, the outer diameter is 4.7 meters, the total height is nearly 3 meters, the thickness of the head part reaches 170mm, and the thickness of the flange part reaches 850mm. The thermal cutting device for radioactive metal waste in Example 1 is used in conjunction with the thermal cutting method for radioactive metal waste in Example 2 for cutting, and the thermal cutting head is a flame thermal cutting head.

Comparative case 1: For the top cover of the reactor pressure vessel, the total weight is 58 tons, the outer diameter is 4.7 meters, the total height is nearly 3 meters, the thickness of the head part reaches 170mm, and the thickness of the flange part reaches 850mm. Use the traditional diamond wire saw cutting method for cutting.

Comparative case 2: For the top cover of the reactor pressure vessel, the total weight is 58 tons, the outer diameter is 4.7 meters, the total height is nearly 3 meters, the thickness of the head part reaches 170mm, and the thickness of the flange part reaches 850mm. Cut using traditional waterjet cutting methods.

Table 1 Parameters and test results of application cases and comparison cases

cutting time Secondary Waste Production Applications 300 hours 5 tons Comparative case 1 1500 hours 20 tons Comparative case 2 2500 hours 300 tons

The test results in Table 1 show that the cutting time in the application case is greatly shortened and the cutting efficiency is high, only 1/5-1/8 of the comparison case, and the output of secondary waste is very low, only 1/4-1/60 of the comparison case.

The radioactive metal waste thermal cutting device of the present invention, through the cooperation of the negative pressure station body module and the negative pressure system, ensures that the radioactivity is contained in the negative pressure station without leakage, and ensures the safety of the environment and personnel; by means of the video monitoring system and Centralized control system, cutting, transportation and other operations can be operated remotely manually or automatically, without the need for personnel to work manually at close range, so the radiation dose to personnel is greatly reduced; it is suitable for a variety of thermal cutting heads, and can be applied to flame cutting and plasma cutting; a complete set The device can cut radioactive thick and large pieces, including large nuclear power equipment such as evaporators, voltage stabilizers, and reactor pressure vessel top covers.

The above-mentioned embodiments are only to illustrate the technical concept and characteristics of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention shall fall within the protection scope of the present invention.

Claims (7)

1. The radioactive metal waste thermal cutting device is characterized by comprising a negative pressure station body module, a negative pressure system and a cutting and collecting module, wherein the negative pressure system is used for providing negative pressure for the negative pressure station body module and filtering particles, dust and radioactive aerosol generated by thermal cutting of the radioactive metal waste, the cutting and collecting module comprises a thermal cutting device, and the negative pressure station body module is used for placing the radioactive metal waste to be cut and the thermal cutting device;

the negative pressure station body module comprises a negative pressure station body, an air inlet window, a window and a soft curtain, wherein a traction guide rail is arranged at the bottom of the negative pressure station body and penetrates through the negative pressure station body, a collection transportation trolley is arranged on the traction guide rail, the air inlet window and the window are arranged on the side face of the negative pressure station body, and the soft curtain is arranged at the part of the negative pressure station body, through which the traction guide rail and the collection transportation trolley penetrate;

the negative pressure station body is of a cuboid type, the negative pressure station body comprises a top cover plate and four side plates, two adjacent side plates are bonded through sealant, a lifting lug is further arranged on the top cover plate, a thermal cutting area for cutting radioactive metal waste is arranged in the negative pressure station body, and the radioactive metal waste to be cut and the thermal cutting device are arranged in the thermal cutting area;

the negative pressure system comprises an air draft main fan, a dust filter, a radioactive aerosol filter and an air outlet which are sequentially communicated with each other through an air pipe and are arranged outside a negative pressure station body, an air inlet, an air supply fan, an air draft fan, an air suction opening and three pressure gauges which are arranged in the negative pressure station body, wherein the air inlet is arranged at the air inlet window, the air supply fan is used for supplying air to a hot cutting area so that particles, dust and radioactive aerosol generated by hot cutting radioactive metal wastes are blown to the inlet of the air draft fan, the air draft fan is used for receiving the particles, dust and radioactive aerosol generated by the hot cutting area and supplying air to the air pipe, the air draft fan and the air suction opening are respectively communicated with the air draft main fan through the air pipe, the air draft main fan is used for receiving the particles, the dust and the radioactive aerosol received by the air draft fan and the air suction opening which are absorbed by the negative pressure station body, one pressure gauge among the three pressure gauges is arranged in the cutting area, and two pressure gauges are respectively close to the air suction opening and the air suction opening which are respectively arranged in the cutting area.

2. The radioactive metal waste thermal cutting apparatus of claim 1, wherein the negative pressure system further comprises a combustible gas concentration monitor, a radioactive dose monitor, and a plurality of monitoring cameras disposed within the negative pressure station body.

3. The radioactive metal waste thermal cutting apparatus according to claim 2, wherein the cutting and collecting module includes a collecting device and the thermal cutting device, the thermal cutting device includes a gantry, an actuator head provided on the gantry, a thermal cutting head provided on the actuator head, and a support stand for supporting radioactive metal waste to be cut, the gantry is movable in a Y-axis direction, the actuator head is retractable up and down and movable in an X-axis direction on the gantry, the collecting device includes the collecting and transporting carriage and the traction rail, and the collecting and transporting carriage is for receiving a cut block of radioactive metal waste to be cut.

4. The radioactive metal waste thermal cutting apparatus of claim 3, wherein a blanking port is formed in a central portion of the support frame, and the cut material block falls from the blanking port to the collection and transportation cart.

5. The radioactive metal waste thermal cutting apparatus of claim 4, wherein the thermal cutting head is a flame cutting head or a plasma cutting head.

6. A method of hot cutting radioactive metal waste according to any one of claims 1 to 5, comprising the steps of:

placing a thermal cutting head and radioactive metal waste to be cut; starting a negative pressure system to enable negative pressure to be formed in the negative pressure station body; cutting radioactive metal waste to be cut, transporting and collecting the dropped cut pieces.

7. The method of thermal cutting of radioactive metal waste of claim 6, wherein activating the negative pressure system comprises the steps of: starting an air draft main fan, an air supply fan and an air draft fan; observing and confirming that the air inlet window opens air inlet into the negative pressure station body, and the soft curtain drifts towards the inner side of the negative pressure station body; the pressure gauge readings were observed and confirmed to be negative.

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