Automatic loading system and method for new fuel of pebble bed high temperature reactor

Abstract

The present invention proposes an automatic loading system and method for new fuel of a pebble bed high temperature reactor. The system includes a loading subsystem, a pipeline monitoring subsystem, a purge subsystem and a lifting subsystem. The loading subsystem includes a loader, a surface quality detection device and a reversing conveying device which are sequentially connected through a ball-dropping pipeline. The outlets of the reversing conveying device are respectively connected to a fuel operating system and a broken ball storage tank. The reversing conveying device determines the conveying direction of the new fuel according to the detection results of the surface quality detection device and the control instructions. The present invention realizes fully automatic single loading of new fuel and improves the efficiency of new fuel loading. The present invention is equipped with a pipeline monitoring subsystem, which can monitor the isolation effect of the fuel operating system and the new fuel loading subsystem in real time. Once radioactive substances leak out, the boundary isolation valve of the new fuel loading subsystem can be closed in real time to prevent the leakage of radioactive substances and protect the safety of operators.

Description

Technical Field

[0001] The invention relates to the field of reactor engineering technology, and in particular to an automatic loading system and method for new fuel of a pebble bed type high temperature reactor. Background Art

[0002] The pebble bed high temperature gas-cooled reactor is an advanced nuclear reactor with good inherent safety, which can be used for efficient power generation and high temperature heating. It is one of the preferred reactor types in the fourth generation nuclear energy system in the international nuclear energy field. By utilizing the favorable geometric shape of spherical fuel elements, the pebble bed high temperature gas-cooled reactor can realize the non-stop refueling function of the reactor. According to the operation requirements of the reactor, the new fuel supply system needs to replenish a certain number of new fuel elements to the core every day to maintain sufficient backup reactivity of the reactor. According to the existing technology, the new fuel elements are generally discretely stacked or tandemly bagged in the new fuel storage tank. When loading the new fuel, the new fuel elements are mainly taken out from the new fuel storage tank by manual methods, and then loaded into the new fuel supply system, and then loaded into the reactor core. This loading method is inefficient, requires a lot of manpower and material resources, and is not economical. In addition, the new fuel may be mixed with unqualified fuel, or the fuel may carry dust or debris. If it is selected or dusted by manual methods, the efficiency will be lower. Therefore, it is necessary to develop a new fuel automatic loading system and method suitable for a pebble bed high temperature reactor to solve the problem of low efficiency of new fuel loading under the existing technology. Summary of the invention

[0003] The purpose of the present invention is to provide a new fuel automatic loading system and method for a pebble bed high temperature reactor, so as to overcome the problem of low new fuel loading efficiency in the prior art.

[0004] On the one hand, the present application proposes an automatic loading system for new fuel of a pebble bed high-temperature reactor, including: a loading subsystem and a pipeline monitoring subsystem, the loading subsystem includes a loader, a surface quality detection device and a reversing conveying device which are connected in sequence through a ball-dropping pipeline, the outlet of the reversing conveying device is respectively connected to a fuel operating system and a broken ball storage tank, the reversing conveying device determines the conveying direction of the new fuel according to the detection result of the surface quality detection device and the control instruction, and a main isolation valve is connected between the loading subsystem and the fuel operating system.

[0005] The pipeline monitoring subsystem includes a helium mass spectrometer leak detector connected through a monitoring pipeline, one end of the monitoring pipeline is connected to the ball-dropping pipeline between the loader and the surface quality detection device, and the helium mass spectrometer leak detector is connected through a control system and controls the opening and closing of the main isolation valve and the loader.

[0006] The present invention realizes fully automatic single loading of new fuel by setting up a loading subsystem, thereby improving the overall new fuel loading efficiency.

[0007] The present invention is equipped with a new fuel surface quality detection device and a reversing conveying device, which can realize automatic detection and directional distribution of the new fuel surface quality, avoid unqualified fuel elements from entering the fuel operating system and the reactor core, and is beneficial to improving the operating stability of the fuel operating system and the safety of the reactor.

[0008] The present invention is equipped with a new fuel pipeline monitoring subsystem, which can monitor the isolation effect of the fuel operating system and the new fuel loading subsystem in real time. Once radioactive substances leak out, the boundary isolation valve of the new fuel loading subsystem can be closed in real time to prevent the leakage of radioactive substances and protect the safety of operators.

[0009] In some embodiments, the feed port of the loader is connected to a new fuel storage tank via a quick-connect structure, and a ball flow baffle for controlling material falling is provided in the new fuel storage tank.

[0010] In some embodiments, the loader is provided with a fuel outlet and a dust outlet. The fuel outlet is connected to the surface quality detection device through a ball-dropping pipeline, and the dust outlet is connected to a dust tank for collecting dust or debris of the fuel balls.

[0011] In some embodiments, a purge subsystem is also included, and the purge subsystem includes a main purge pipeline and an auxiliary purge pipeline. One end of the main purge pipeline is connected to the gas source, and the other end of the main purge pipeline is connected to the pipeline between the charging subsystem and the main isolation valve. Both ends of the auxiliary purge pipeline are respectively connected to the pipelines at both ends of the helium mass spectrometer leak detector, and the other end of the monitoring pipeline is the atmospheric environment. The front and rear ends of the helium mass spectrometer leak detector are respectively connected to the monitoring isolation valve, and the monitoring isolation valve is located between the connection between the auxiliary purge pipeline and the monitoring pipeline and the helium mass spectrometer leak detector.

[0012] The present invention is equipped with a new fuel pipeline purge system, which can regularly perform dust purge of the new fuel loading subsystem to prevent the deposited graphite dust and debris from affecting the normal delivery of the new fuel elements.

[0013] In some embodiments, a first pipeline filter and an air compressor are connected to the main purge pipeline, the first pipeline filter is connected between the air source and the air compressor, and a second pipeline filter is connected to the auxiliary purge pipeline.

[0014] In some embodiments, when the height of the fuel operating system is greater than the height of the charging subsystem, a lifting subsystem for lifting the fuel balls from a lower position to a higher position is connected between the charging subsystem and the fuel operating system.

[0015] In some embodiments, the lifting subsystem is connected in parallel to the pipeline between the loading subsystem and the fuel operating system. The lifting subsystem includes a fan, a third pipeline filter and a ball-gas separator connected in sequence through the lifting pipeline. The ball-gas separator is arranged on the side close to the fuel operating system. The fan lifts the fuel balls into the ball-gas separator through positive pressure delivery or negative pressure suction, and then transports them to the fuel operating system. A check mechanism is connected between the lifting subsystem and the loading subsystem to prevent the fuel balls from flowing back.

[0016] In some embodiments, the charging subsystem is provided with two ball-dropping pipelines, which are commonly connected to a dust tank, and the charging subsystem is provided with two monitoring pipelines, which are commonly connected to a helium mass spectrometer leak detector.

[0017] On the other hand, the present application proposes a method for automatically loading new fuel into a pebble bed high temperature reactor, using the above-mentioned automatic loading system for new fuel into a pebble bed high temperature reactor, comprising the following steps:

[0018] Loading process: the ball-dropping pipeline is in an open state, and the fuel balls fall from the new fuel storage tank into the loader. The loader conveys the fuel balls to the surface quality detection device on the one hand, and discharges the dust or debris carried by the fuel balls into the dust tank on the other hand; the surface quality detection device performs quality detection on the fuel balls, and the fuel balls after detection are conveyed to the reversing conveying device, and the detection result information is sent to the reversing conveying device. After receiving the detection result information, the reversing conveying device converts it into an action instruction for the fuel balls. The reversing conveying device conveys qualified fuel balls to the fuel operating system, and conveys unqualified fuel balls to the damaged ball storage tank;

[0019] Monitoring process: The monitoring pipeline is in the open state, the purge pipeline is in the closed state, and the helium mass spectrometer leak detector monitors the gas sucked by the charging subsystem in real time. When the helium leak rate exceeds the standard, the helium mass spectrometer leak detector sends a feedback signal, and the control system closes the main isolation valve and stops charging at the same time; when the fault is handled, the helium mass spectrometer leak detector sends a feedback signal, and the control system opens the main isolation valve and resumes charging at the same time;

[0020] Purge process: the main purge pipeline and the auxiliary purge pipeline are in the open state, the main isolation valve, the monitoring isolation valve and the loader fuel outlet are all in the closed state, the air compressor is started, and the purge gas is filtered by the second pipeline filter and then discharged into the atmosphere after purging.

[0021] In some embodiments, during the loading process, when the height of the fuel operating system is greater than the height of the loading subsystem, the qualified fuel balls transported by the reversing conveying device are transported to the ball-gas separator by the positive pressure delivery or negative pressure suction of the fan, and the fuel balls after gas-solid separation in the ball-gas separator are transported to the fuel operating system.

[0022] The beneficial effects of the present invention are:

[0023] (1) The present invention realizes fully automatic single-fuel loading of new fuel by setting up a loading subsystem, thereby improving the overall new fuel loading efficiency;

[0024] (2) The present invention is equipped with a new fuel surface quality detection device and a reversing conveying device, which can realize automatic detection of the surface quality of the new fuel and directional distribution, thereby preventing unqualified fuel elements from entering the fuel operating system and the reactor core, which is beneficial to improving the operating stability of the fuel operating system and the safety of the reactor;

[0025] (3) All pipelines and equipment of the present invention work under air atmosphere, which solves the technical problem of the need for pressure relief to handle equipment failure when using a single-loop high-pressure helium gas to transport new fuel elements in the prior art;

[0026] (4) The present invention is equipped with a new fuel pipeline monitoring subsystem, which can monitor the isolation effect of the fuel operating system and the new fuel loading subsystem in real time. Once radioactive substances leak out, the boundary isolation valve of the new fuel loading subsystem can be closed in real time to prevent the leakage of radioactive substances and protect the safety of operators;

[0027] (5) The present invention is equipped with a new fuel pipeline purge system, which can regularly perform dust purge of the new fuel loading subsystem to prevent the deposited graphite dust and debris from affecting the normal delivery of the new fuel elements.

[0028] (6) The present invention is equipped with a new fuel lifting subsystem, which can lift the new fuel elements from the lower loading subsystem to the higher fuel operating system through the negative pressure suction or positive pressure delivery of the fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings.

[0030] in:

[0031] Figure 1 It is a structural schematic diagram of the automatic new fuel loading system for a pebble bed high temperature reactor when the height of the loading subsystem is higher than the fuel operating system;

[0032] Figure 2 It is a structural schematic diagram of the automatic new fuel loading system for a pebble bed high temperature reactor when the height of the loading subsystem is lower than the fuel operation system;

[0033] Reference numerals:

[0034] 101-new fuel storage tank, 102-loading machine, 103-the first isolation valve of the ball circuit, 104-the second isolation valve of the ball circuit, 105-dust tank, 106-surface quality detection device, 107-reversing conveying device, 108-main isolation valve, 109-the third isolation valve of the ball circuit, 110-broken ball storage tank, 111-check mechanism;

[0035] 201-monitoring the first isolation valve, 202-monitoring the second isolation valve, 203-helium mass spectrometer leak detector, 204-monitoring the third isolation valve;

[0036] 301-first pipeline filter, 302-air compressor, 303-purge first isolation valve, 304-purge second isolation valve, 305-second pipeline filter;

[0037] 401- fan, 402- cooler, 403- third pipeline filter, 404- lift first isolation valve, 405- ball-gas separator, 406- lift second isolation valve, 407- lift section pipeline. DETAILED DESCRIPTION

[0038] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0039] The following describes an automatic new fuel loading system for a pebble bed high temperature reactor according to an embodiment of the present invention with reference to the accompanying drawings.

[0040] like Figure 1 As shown, an embodiment of the present application provides, on the one hand, an automatic loading system for new fuel of a pebble bed high temperature reactor, comprising: a loading subsystem, a pipeline monitoring subsystem and a purge subsystem.

[0041] The loading subsystem includes a new fuel storage tank 101, a loading machine 102, a surface quality detection device 106 and a reversing conveying device 107, wherein the new fuel storage tank 101 is connected to the loading machine 102 via a quick-connect structure, and a ball flow baffle for controlling the falling of the fuel is provided in the new fuel storage tank 101. After the new fuel storage tank 101 is connected to the loading machine 102, the ball flow baffle is opened, and the new fuel element (i.e., the fuel ball) enters the loading machine 102 by gravity.

[0042] The loader 102 is an automatic loader 102, and is provided with a fuel outlet and a dust outlet. The fuel outlet is connected to the surface quality detection device 106 through a ball drop pipeline, and the dust outlet is connected to a dust tank 105 for collecting dust or debris generated by the fuel balls during the loading process. The loader 102 can achieve the function of removing dust or debris by setting a screen or other structure, which is a prior art and will not be described in detail here.

[0043] The loader 102, the surface quality detection device 106 and the reversing conveying device 107 are connected in sequence through the ball-dropping pipeline. The loader 102 performs the unified conveying function of the new fuel, and conveys the fuel balls stored in the new fuel storage tank 101 to the downstream ball-dropping pipeline one by one.

[0044] The downstream of the loader 102 is connected to a surface quality detection device 106, which uses a three-dimensional visual scanning technology to identify scratches and defects on the surface of the fuel ball and determine whether the acceptance criteria are met. This technology is an existing technology and will not be described in detail here.

[0045] The downstream of the surface quality detection device 106 is connected to the reversing conveying device 107, and the outlet of the reversing conveying device 107 is respectively connected to the fuel operating system and the broken ball storage tank 110. The reversing conveying device 107 determines the conveying direction of the new fuel according to the detection result of the surface quality detection device 106 and the control instruction. Unqualified new fuel elements are conveyed to the broken ball storage tank 110, and qualified and intact new fuel elements are conveyed to the fuel operating system.

[0046] In some specific embodiments, the loading subsystem can be designed as one row of ball-dropping pipelines, or can be designed as two or more rows of ball-dropping pipelines according to the loading requirements. Considering the principle of redundant design, it is preferred to design two rows of ball-dropping pipelines to ensure the reliability of automatic loading.

[0047] When two rows of ball-dropping pipelines are designed, the two ball-dropping pipelines share a dust tank 105, that is, the dust outlets of the two loaders 102 are connected to the same dust tank 105 through pipelines, and the first ball circuit isolation valve 103 is respectively connected to the pipeline to control the falling of dust. For example, when the dust tank 105 is fully loaded, the first ball circuit isolation valve 103 needs to be closed, and the dust tank 105 is emptied before the first ball circuit isolation valve 103 is opened; for another example, the loader 102 can accumulate dust to a certain extent before opening the first ball circuit isolation valve 103 to discharge dust.

[0048] A second ball circuit isolation valve 104 is connected between the loader 102 and the surface quality detection device 106 to control the on-off of the ball dropping pipeline.

[0049] A main isolation valve 108 is connected between the loading subsystem and the fuel operating system. Specifically, the main isolation valve 108 is connected between the reversing conveying device 107 and the fuel operating system. The main isolation valve 108 is used to control whether new fuel elements continue to be introduced into the fuel operating system.

[0050] A third ball circuit isolation valve 109 is connected to the pipeline between the reversing conveying device 107 and the damaged ball storage tank 110 to control the drop of unqualified new fuel elements.

[0051] The pipeline monitoring subsystem includes a helium mass spectrometer leak detector 203 connected through a monitoring pipeline. One end of the monitoring pipeline is connected to the ball-dropping pipeline between the loader 102 and the surface quality detection device 106 through a tee. The helium mass spectrometer leak detector 203 is connected through a control system and controls the opening and closing of the main isolation valve 108 and the loader 102. The main function of the pipeline monitoring subsystem is to monitor whether there is helium leakage in the fuel operating system. Once helium leakage is detected, the main isolation valve 108 between the loading subsystem and the fuel operating system will be closed in time to prevent the leakage of radioactive substances and protect the safety of operators.

[0052] In some specific embodiments, the monitoring pipeline includes a monitoring main pipeline and monitoring branch pipelines. The number of columns of the monitoring branch pipelines is matched with the number of columns of the ball-dropping pipelines of the charging subsystem. If two columns of ball-dropping pipelines are provided, each column of ball-dropping pipelines is connected to a monitoring branch pipeline. The two monitoring branch pipelines are provided in parallel and are connected to a monitoring main pipeline. The helium mass spectrometer leak detector 203 is connected to the monitoring main pipeline. Each monitoring branch pipeline is connected to a first monitoring isolation valve 201. The second monitoring isolation valve 202 and the third monitoring isolation valve 204 are connected to the front and rear ends of the helium mass spectrometer leak detector 203 on the monitoring main pipeline. One end of the monitoring main pipeline is connected to the atmospheric environment.

[0053] The purge subsystem includes a main purge pipeline and an auxiliary purge pipeline. One end of the main purge pipeline is connected to the gas source, and the other end of the main purge pipeline is connected to the pipeline between the charging subsystem and the main isolation valve 108. Specifically, the other end of the main purge pipeline is connected to the ball-dropping pipeline between the reversing conveying device 107 and the main isolation valve 108. The main purge pipeline is connected with the first pipeline filter 301, the air compressor 302 and the first purge isolation valve 303 in sequence starting from the gas source. The first pipeline filter 301 is used to filter out impurities in the air to prevent impurities from being brought into the system. The air compressor 302 is used to convert air into a high-pressure gas source. The first purge isolation valve 303 is used to control the start or stop of the purge action.

[0054] The two ends of the auxiliary purge pipeline are respectively connected to the monitoring main pipeline at both ends of the helium mass spectrometer leak detector 203 through three-way connections. The monitoring second isolation valve 202 is located on the left side of the helium mass spectrometer leak detector 203, and the monitoring third isolation valve 204 is located on the right side of the helium mass spectrometer leak detector 203. The two ends of the auxiliary purge pipeline are respectively connected to the left side of the monitoring second isolation valve 202 and the right side of the monitoring third isolation valve 204. The auxiliary purge pipeline is connected with the purge second isolation valve 304 and the second pipeline filter 305. One end of the second pipeline filter 305 is connected to the purge second isolation valve 304, and the other end is connected to the atmospheric environment. The second pipeline filter 305 is used to filter the impurities after the purge so that the air discharged to the atmosphere is not contaminated by impurities.

[0055] The function of the pipeline purge subsystem is to regularly purge the ball drop pipeline of the loading subsystem to prevent graphite dust and debris deposited in the pipeline from affecting the normal delivery of new fuel elements.

[0056] In some specific embodiments, if two rows of ball-dropping pipelines are provided, a branch is connected in parallel on the main purge pipeline, and the branch is connected to the second ball-dropping pipeline. One end of the branch is connected to the pipeline downstream of the air compressor 302, and the other end of the branch is connected between the reversing conveying device 107 and the main isolation valve 108 on the second ball-dropping pipeline. A first purge isolation valve 303 is also connected to the branch. This is equivalent to connecting two parallel branches downstream of the air compressor 302, each branch being connected to a first purge isolation valve 303, and the two branches being connected to two ball-dropping pipelines respectively. If the ball-dropping pipeline is provided with multiple rows, the number of branches is equal to the number of rows of the ball-dropping pipelines.

[0057] The above-mentioned loading subsystem mainly relies on gravity to transport new fuel elements. The connected ball-dropping pipeline is arranged to be tilted downward or vertically arranged from the inlet end to the outlet end, so that the fuel balls can roll from the upstream device to the downstream device by their own gravity.

[0058] In some specific embodiments, the system includes two situations, one is that the height of the loading subsystem is higher than the fuel operating system and its interface, and the other is that the height of the loading subsystem is lower than the fuel operating system and its interface. If the height of the loading subsystem is higher than the fuel operating system and its interface, the fuel balls can be transported from the new fuel storage tank 101 to the fuel operating system by their own gravity throughout the whole process. If the height of the loading subsystem is lower than the fuel operating system and its interface, a lifting subsystem is further connected between the loading subsystem and the fuel operating system to lift the fuel balls from the loading subsystem located at a lower position to the fuel operating system located at a higher position.

[0059] In some specific embodiments, Figure 2 As shown, the lifting subsystem is connected in parallel to the pipeline between the loading subsystem and the fuel operating system. The lifting subsystem includes a fan 401, a cooler 402, a third pipeline filter 403, a lifting first isolation valve 404 and a ball-gas separator 405 connected in sequence through the lifting pipeline. The ball-gas separator 405 is arranged on the side close to the fuel operating system. The fan 401 lifts the fuel balls into the ball-gas separator 405 through positive pressure delivery or negative pressure suction, and then transports them to the fuel operating system. The cooler 402 is used to cool the fan 401. If the fan 401 has its own cooling device, the cooler 402 does not need to be connected additionally. The third pipeline filter 403 is used to filter impurities in the positive pressure or negative pressure wind to prevent impurities from being brought into the system.

[0060] Specifically, the ball-gas separator 405 is provided with an air outlet, a ball inlet and a ball outlet. The air outlet is connected to the first isolation valve 404 of the lifting pipeline, the ball inlet is connected to the main isolation valve 108 of the ball-dropping pipeline, and the ball outlet is connected to the fuel operating system. The specific structure of the ball-gas separator 405 can refer to the gas-solid separator, that is, the fuel ball is sucked into the separator from the ball inlet through the fan 401, falls on the outward-inclined conveying channel in the separator, and can then be output from the ball outlet by the fuel ball's own gravity. This structure is a prior art and will not be described in detail here.

[0061] The lifting section pipeline 407 of the lifting subsystem and the loading subsystem constitutes a closed gas-solid two-phase flow conveying loop. The main function of the lifting subsystem is to suck the new fuel element from a low place under negative pressure or pressurize it under positive pressure to a high place. Specifically, the lifting section pipeline 407 is connected between the main isolation valve 108 and the ball-gas separator 405. The fan 401 conveys the fuel ball to the ball inlet of the ball-gas separator 405 through the lifting section pipeline 407.

[0062] In some specific embodiments, the blower 401 is a Roots blower. When the lifting subsystem lifts the new fuel element by positive pressure delivery, the Roots blower is a positive pressure blower; when the lifting subsystem lifts the new fuel element by negative pressure suction, the Roots blower is a negative pressure blower.

[0063] In some specific embodiments, a check mechanism 111 is connected between the lifting subsystem and the loading subsystem to prevent the fuel balls from flowing back. When the lifting subsystem uses positive pressure to lift new fuel elements, the wind sent out may blow the fuel balls back along the original path of the ball-dropping pipeline, so the check mechanism 111 is set to prevent this from happening. The principle of the check mechanism 111 is equivalent to that of a check valve, and the fuel balls can only be transported in one direction.

[0064] Specifically, the non-return mechanism 111 is located between the connection between the main purge pipeline and the ball drop pipeline and the connection between the lift pipeline and the ball drop pipeline.

[0065] In some specific embodiments, if two rows of ball-dropping pipelines are provided, one end of the lifting pipeline is respectively connected to two parallel branches, each branch is connected to a corresponding ball-dropping pipeline, and each branch is connected to a lifting second isolation valve 406. The other end of the lifting pipeline is also respectively connected to two parallel branches, each branch is connected to a lifting first isolation valve 404 and a ball-gas separator 405, and the corresponding ball-gas separator 405 on each branch is respectively connected to a ball-dropping pipeline through a lifting section pipeline 407. The two ball-dropping pipelines share a set of fans 401, coolers 402 and third pipeline filters 403.

[0066] In some specific embodiments, a check mechanism may also be connected to the fuel operating system to prevent the fuel balls in the fuel operating system from being sucked back by the fan 401 .

[0067] All the process flows of the present invention are carried out in an air atmosphere environment, that is, the working medium of the system is new fuel elements and air.

[0068] On the other hand, the embodiment of the present application provides a method for automatically loading new fuel for a pebble bed high temperature reactor, using the above-mentioned automatic loading system for new fuel for a pebble bed high temperature reactor. There are two situations, one is that the height of the loading subsystem is higher than the fuel operating system and its interface, and the other is that the height of the loading subsystem is lower than the fuel operating system and its interface.

[0069] (1) Figure 1 As shown, when the height of the loading subsystem is higher than the fuel operating system and its interface, the automatic loading method includes the following steps:

[0070] Loading process: During normal operation, the ball drop pipeline is in an open state, that is, the first isolation valve 103, the second isolation valve 104, the third isolation valve 109 and the main isolation valve 108 of the ball circuit are opened, the new fuel storage tank 101 is docked with the loader 102, and automatic loading begins according to the requirements of the fuel operating system. The fuel balls fall from the new fuel storage tank 101 into the loader 102, and the loader 102 unloads the new fuel elements in a single unit. The loader 102 transports the fuel balls to the surface quality detection device 106 on the one hand, and discharges the dust or debris carried by the fuel balls into the dust tank 105 for storage on the other hand. The surface quality detection device 106 performs quality detection on the fuel balls. The detected fuel balls are transported to the reversing conveying device 107, and the detection result information is sent to the reversing conveying device 107 to determine the conveying direction of the fuel balls. The reversing conveying device 107 receives the detection result information and converts it into action instructions for the fuel balls. The reversing conveying device 107 transports qualified fuel balls to the fuel operating system, and transports unqualified fuel balls to the broken ball storage tank 110.

[0071] Monitoring process: During normal operation, the monitoring pipeline is in an open state, that is, the first isolation valve 201, the second isolation valve 202 and the third isolation valve 204 are open. The purge pipeline is in a closed state, that is, the first isolation valve 303 and the second isolation valve 304 are closed. The helium mass spectrometer leak detector 203 uses a negative pressure suction gun method to monitor the gas sucked from the ball drop pipeline of the charging subsystem in real time. When the helium leak rate exceeds the standard, the helium mass spectrometer leak detector 203 sends a feedback signal, and the control system closes the main isolation valve 108 and stops charging; when the fault is handled, the helium mass spectrometer leak detector 203 sends a feedback signal, and the control system opens the main isolation valve 108 and resumes charging.

[0072] Purge process: During normal operation, the main purge pipeline, auxiliary purge pipeline and monitoring branch pipeline are in an open state, that is, the first purge isolation valve 303, the second purge isolation valve 304, and the first monitoring isolation valve 201 are opened, and the second ball circuit isolation valve 104, the main isolation valve 108, the second monitoring isolation valve 202, and the third monitoring isolation valve 204 are closed. The air compressor 302 is started, and the purge gas purges the ball drop pipeline and is then discharged to the atmosphere after being filtered by the second pipeline filter 305.

[0073] (2) Figure 2 As shown, when the height of the loading subsystem is lower than the fuel operating system and its interface, the automatic loading method includes the following steps:

[0074] Loading process: During normal operation, the ball drop pipeline and the lifting pipeline are in an open state, that is, the first isolation valve 103 of the ball circuit, the second isolation valve 104 of the ball circuit, the third isolation valve 109 of the ball circuit, the main isolation valve 108, the first isolation valve 404 of the lifting, and the second isolation valve 406 of the lifting are opened, and the new fuel storage tank 101 is docked with the loader 102, and automatic loading begins according to the requirements of the fuel operating system. The fuel ball falls from the new fuel storage tank 101 into the loader 102, and the loader 102 unloads the new fuel element singly. On the one hand, the loader 102 transports the fuel ball to the surface quality detection device 106, and on the other hand, it discharges the dust or debris carried by the fuel ball into the dust tank 105 for storage. The surface quality detection device 106 performs quality detection on the fuel balls. The detected fuel balls are transported to the reversing conveying device 107, and the detection result information is sent to the reversing conveying device 107 to determine the conveying direction of the fuel balls. The reversing conveying device 107 receives the detection result information and converts it into an action instruction for the fuel balls. The reversing conveying device 107 transports the qualified fuel balls to the starting end of the lifting section pipeline 407. The fuel balls are lifted to the top of the lifting section pipeline 407 by the air force delivered by the fan 401, and the gas-solid two-phase separation is carried out in the ball-gas separator 405. The fuel balls enter the fuel operating system by their own gravity. The reversing conveying device 107 transports the unqualified fuel balls to the broken ball storage tank 110.

[0075] Monitoring process: During normal operation, the monitoring pipeline is in an open state, that is, the first isolation valve 201, the second isolation valve 202 and the third isolation valve 204 are open. The purge pipeline is in a closed state, that is, the first isolation valve 303 and the second isolation valve 304 are closed. The helium mass spectrometer leak detector 203 uses a negative pressure suction gun method to monitor the gas sucked from the ball drop pipeline of the charging subsystem in real time. When the helium leak rate exceeds the standard, the helium mass spectrometer leak detector 203 sends a feedback signal, and the control system closes the main isolation valve 108 and stops charging; when the fault is handled, the helium mass spectrometer leak detector 203 sends a feedback signal, and the control system opens the main isolation valve 108 and resumes charging.

[0076] Purge process: During normal operation, the main purge pipeline, auxiliary purge pipeline and monitoring branch pipeline are in an open state, that is, the first purge isolation valve 303, the second purge isolation valve 304, the monitoring first isolation valve 201 are opened, the second ball circuit isolation valve 104, the main isolation valve 108, the monitoring second isolation valve 202, the monitoring third isolation valve 204 are closed, and the second isolation valve 406 is lifted. The air compressor 302 is started, and the purge gas purges the ball drop pipeline and is then filtered by the second pipeline filter 305 and discharged to the atmosphere.

[0077] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0078] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0079] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0080] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0081] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0082] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An automatic loading system for new fuel of a pebble bed high temperature reactor, characterized in that: include: A charging subsystem, wherein the charging subsystem comprises a charging machine, a surface quality detection device and a reversing conveying device which are sequentially connected through a ball-dropping pipeline, wherein the outlet of the reversing conveying device is respectively connected to a fuel operating system and a broken ball storage tank, and the reversing conveying device determines the conveying direction of new fuel according to the detection result of the surface quality detection device and the control instruction, and a main isolation valve is connected between the charging subsystem and the fuel operating system; A pipeline monitoring subsystem, the pipeline monitoring subsystem includes a helium mass spectrometer leak detector connected via a monitoring pipeline, one end of the monitoring pipeline is connected to the ball drop pipeline between the loader and the surface quality detection device, and the helium mass spectrometer leak detector is connected via a control system and controls the opening and closing of the main isolation valve and the loader; It also includes a purge subsystem, which includes a main purge pipeline and an auxiliary purge pipeline, one end of the main purge pipeline is connected to the gas source, the other end of the main purge pipeline is connected to the pipeline between the charging subsystem and the main isolation valve, the two ends of the auxiliary purge pipeline are respectively connected to the pipelines at the two ends of the helium mass spectrometer leak detector, the other end of the monitoring pipeline is the atmospheric environment, the front and rear ends of the helium mass spectrometer leak detector are respectively connected to the monitoring isolation valve, and the monitoring isolation valve is located between the connection between the auxiliary purge pipeline and the monitoring pipeline and the helium mass spectrometer leak detector; The main purge pipeline is connected with a first pipeline filter and an air compressor, the first pipeline filter is connected between the air source and the air compressor, and the auxiliary purge pipeline is connected with a second pipeline filter.

2. The automatic new fuel loading system for pebble bed high temperature reactor according to claim 1 is characterized in that: The feed port of the loader is connected to a new fuel storage tank via a quick-connect structure, and a ball flow baffle for controlling material falling is arranged in the new fuel storage tank.

3. The automatic new fuel loading system for pebble bed high temperature reactor according to claim 1 is characterized in that: The loader is provided with a fuel outlet and a dust outlet. The fuel outlet is connected to a surface quality detection device through a ball-dropping pipeline, and the dust outlet is connected to a dust tank for collecting dust or debris of the fuel balls.

4. The automatic new fuel loading system for pebble bed high temperature reactor according to claim 1 is characterized in that: When the height of the fuel operating system is greater than that of the charging subsystem, a lifting subsystem for lifting the fuel balls from a lower position to a higher position is connected between the charging subsystem and the fuel operating system.

5. The automatic new fuel loading system for pebble bed high temperature reactor according to claim 4 is characterized in that: The lifting subsystem is connected in parallel to the pipeline between the loading subsystem and the fuel operating system. The lifting subsystem includes a fan, a third pipeline filter and a ball-gas separator which are connected in sequence through the lifting pipeline. The ball-gas separator is arranged on the side close to the fuel operating system. The fan lifts the fuel balls into the ball-gas separator through positive pressure delivery or negative pressure suction, and then transports them to the fuel operating system. A check mechanism is connected between the lifting subsystem and the loading subsystem to prevent the fuel balls from flowing back.

6. The automatic new fuel loading system for a pebble bed high temperature reactor according to any one of claims 1 to 5, characterized in that: The charging subsystem is provided with two ball-dropping pipelines, which are commonly connected to a dust tank; and the charging subsystem is provided with two monitoring pipelines, which are commonly connected to a helium mass spectrometer leak detector.

7. A method for automatically loading new fuel into a pebble bed high temperature reactor, characterized in that: The automatic new fuel loading system for a pebble bed high temperature reactor according to any one of claims 1 to 6 comprises the following steps: Loading process: the ball-dropping pipeline is in an open state, and the fuel balls fall from the new fuel storage tank into the loader. The loader conveys the fuel balls to the surface quality detection device on the one hand, and discharges the dust or debris carried by the fuel balls into the dust tank on the other hand; the surface quality detection device performs quality detection on the fuel balls, and the fuel balls after detection are conveyed to the reversing conveying device, and the detection result information is sent to the reversing conveying device. After receiving the detection result information, the reversing conveying device converts it into an action instruction for the fuel balls. The reversing conveying device conveys qualified fuel balls to the fuel operating system, and conveys unqualified fuel balls to the damaged ball storage tank; Monitoring process: The monitoring pipeline is in the open state, the purge pipeline is in the closed state, and the helium mass spectrometer leak detector monitors the gas sucked by the charging subsystem in real time. When the helium leak rate exceeds the standard, the helium mass spectrometer leak detector sends a feedback signal, and the control system closes the main isolation valve and stops charging at the same time; when the fault is handled, the helium mass spectrometer leak detector sends a feedback signal, and the control system opens the main isolation valve and resumes charging at the same time; Purge process: the main purge pipeline and the auxiliary purge pipeline are in the open state, the main isolation valve, the monitoring isolation valve and the loader fuel outlet are all in the closed state, the air compressor is started, and the purge gas is filtered by the second pipeline filter and then discharged into the atmosphere after purging.

8. The method for automatically loading new fuel for a pebble bed high temperature reactor according to claim 7, characterized in that: During the loading process, when the height of the fuel operating system is greater than the height of the loading subsystem, the qualified fuel balls transported by the reversing conveying device are transported to the ball-gas separator by the positive pressure delivery or negative pressure suction of the fan, and the fuel balls after gas-solid separation in the ball-gas separator are transported to the fuel operating system.

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