Filtering and cleaning system and method for nuclear power station

Abstract

The invention relates to a filtering and cleaning system and method for a nuclear power plant, the filtering and cleaning system comprises a water pool, a circulating pipeline, a seawater filter, a water pump, a shellfish trap and a jet device, two ends of the circulating pipeline are respectively connected to a water outlet and a water inlet of the water pool; the seawater filter, the water pump and the shellfish trap are sequentially arranged on the circulating pipeline in the flowing direction of fluid; the jet device is provided with a first inlet, a second inlet and a liquid outlet, the first inlet is connected with an outlet of the water pump, the second inlet is connected with a drain outlet of the seawater filter, and the liquid outlet is connected with a water inlet of the pool; the filtering and cleaning system has a filtering state and a jet flow backwashing state, and when the filtering and cleaning system is in the jet flow backwashing state, pressurized fluid flowing through the water pump partially flows into the jet device and generates negative pressure in the jet device; and the fluid flowing through the seawater filter returns to the seawater filter and carries dirt to be discharged to the water tank through the drain outlet, the second inlet and the liquid outlet in sequence.

Description

Technical Field

[0001] This application relates to the field of nuclear power plant technology, and in particular to a filtration and cleaning system and method for nuclear power plants. Background Technology

[0002] The safety of the cold source in a nuclear power plant is one of the key aspects of ensuring its stable operation, and the filtration of impurities such as marine organisms at the intake is particularly important. Currently, nuclear power plants generally install primary filtration equipment such as skimmers and rotary filters at the intake to perform preliminary filtration of seawater, followed by fine filtration through secondary filtration equipment such as seawater filters and shellfish traps to prevent impurities from entering the critical cooling system.

[0003] Existing filtration equipment relies on an additional high-pressure water source. The pressure difference between the filtration equipment and the backwash valve is used to flush and clean the filtration equipment, thus removing the dirt from the cylinder.

[0004] However, for small modular reactor (SMR) nuclear power plants with compact structures and limited space, it is difficult to install traditional backwashing devices (such as adding backwash water pumps), resulting in insufficient backwashing pressure differential for equipment such as seawater filters, thus hindering the effective completion of automatic backwashing operations. Over long-term operation, seawater filters are prone to clogging, affecting not only filtration efficiency but also potentially threatening the safety of the cooling source. Summary of the Invention

[0005] Therefore, it is necessary to provide a filtration and cleaning system and method for nuclear power plants to address the problem of backwashing seawater filters in small modular reactor nuclear power plants with compact structures and limited space.

[0006] This application provides a filtration and cleaning system for a nuclear power plant, the filtration and cleaning system comprising:

[0007] A water tank and a circulation pipeline, wherein the two ends of the circulation pipeline are respectively connected to the outlet and inlet of the water tank;

[0008] Seawater filters, water pumps, and shellfish traps are sequentially installed on the circulation pipeline along the direction of fluid flow;

[0009] The jet ejector has a first inlet, a second inlet, and a liquid outlet. The first inlet is connected to the outlet of the water pump, the second inlet is connected to the drain outlet of the seawater filter, and the liquid outlet is connected to the inlet of the water tank.

[0010] The filtration and cleaning system has a filtration state and a jet backwashing state. When in the filtration state, the fluid in the pool flows back into the pool after being filtered by the seawater filter, the water pump and the shellfish trap in sequence.

[0011] When in the jet backwashing state, part of the pressurized fluid flowing through the water pump flows into the jet injector and generates negative pressure in the jet injector, so that the fluid flowing through the seawater filter returns to the seawater filter and carries the dirt through the drain outlet, the second inlet and the liquid outlet to the water tank in sequence.

[0012] In one embodiment, a first electric valve is provided on the pipeline connecting the outlet of the water pump and the first inlet. The first electric valve is controlled to open or close to switch the state of the filtration and cleaning system.

[0013] In one embodiment, a check valve is provided on the pipeline connecting the inlet and outlet of the water tank.

[0014] In one embodiment, the filtration and cleaning system further includes a drain pipe and a second electric valve, the two ends of which are respectively connected to the outlet of the shellfish trap and the inlet of the pool, and the second electric valve is located on the drain pipe;

[0015] When in the filtration state or the jet backwash state, the second electric valve is configured to be closed;

[0016] The filtration and cleaning system also has a trap backwashing state, in which the second electric valve is configured to open.

[0017] In one embodiment, the jet ejector includes a venturi tube with openings at both ends along the axial direction, namely the first inlet and the outlet. The venturi tube has a through hole on its wall that connects the outside to the internal space of the venturi tube, and the through hole is the second inlet.

[0018] In one embodiment, the filtration and cleaning system further includes a pressure detection component disposed on the seawater filter, the pressure detection component being used to detect the actual pressure difference between the inlet and outlet of the seawater filter.

[0019] In one embodiment, the filtration and cleaning system further includes a flow detection component disposed on the circulation pipeline, the flow detection component being used to detect the fluid flow rate of the circulation pipeline.

[0020] This application also provides a filtration and cleaning method for a nuclear power plant, used in the filtration and cleaning system described in any of the above claims, the filtration and cleaning method comprising:

[0021] Connect the components of the water tank, the circulation pipeline, the seawater filter, the water pump, the shellfish trap, and the jet generator;

[0022] When fluid filtration is required, the fluid is circulated in the circulation pipeline, passing through the seawater filter, the water pump, and the shellfish trap in sequence before flowing back into the pool.

[0023] When the seawater filter needs to be backwashed, a portion of the pressurized fluid flowing through the water pump flows into the jet injector and generates negative pressure within the jet injector, creating a pressure difference between the drain outlet and the second inlet. This causes the fluid within the seawater filter to carry contaminants through the drain outlet, the second inlet, and the liquid outlet sequentially to be discharged into the water tank.

[0024] In one embodiment, a pressure detection component is used to detect the actual pressure difference between the inlet and outlet of the seawater filter;

[0025] When the actual pressure difference is greater than or equal to the preset pressure value, the filtration and cleaning system is controlled to switch from the filtration state to the jet backwashing state.

[0026] In one embodiment, the filtration and cleaning method further includes:

[0027] The first electric valve and the controller are electrically connected. The controller is used to receive the pressure value detected by the pressure detection component and calculate the actual pressure difference. The controller determines the magnitude of the actual pressure difference and the preset pressure value.

[0028] If the pressure difference is greater than or equal to the preset pressure value, the controller controls the first electric valve to open, switching from the filtration state to the jet backwashing state;

[0029] After the jet backwashing state is maintained for a preset time, the controller controls the first electric valve to close, ending the backwashing operation.

[0030] The aforementioned filtration and cleaning system for nuclear power plants connects the two ends of the circulation pipeline to the outlet and inlet of the water tank, respectively. A seawater filter, water pump, and shellfish trap are sequentially installed along the fluid flow direction within the circulation pipeline. In filtration mode, the fluid in the water tank passes sequentially through the seawater filter, water pump, and shellfish trap before returning to the water tank, thus filtering impurities such as marine organisms. The jet jet's first inlet is connected to the water pump outlet, the second inlet to the seawater filter's drain outlet, and the outlet to the water tank inlet. During jet backwashing, a portion of the pressurized fluid flowing after the water pump flows into the jet jet, creating a negative pressure within it. This creates a pressure difference between the seawater filter's drain outlet and the jet jet's second inlet, causing the fluid that has passed through the seawater filter to return to the filter and carry contaminants in the reverse direction, sequentially through the drain outlet, second inlet, and outlet to the water tank.

[0031] The filtration and cleaning system for nuclear power plants proposed in this application does not require additional high-pressure water sources or backwash pumps, which solves the problem that it is difficult to install traditional backwash devices in small modular reactor nuclear power plants with compact structures and limited space. It not only ensures the safety of the cold source of the nuclear power plant, but also eliminates the need for nuclear-grade high-pressure pump sets, simplifies the system structure, and saves equipment layout space and costs. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of a filtration and cleaning system for a nuclear power plant provided in an embodiment of this application.

[0033] Figure 2 A flowchart illustrating a filtration and cleaning method for a nuclear power plant, provided as an embodiment of this application.

[0034] Figure label:

[0035] 100. Pool;

[0036] 200. Circulation pipeline;

[0037] 300. Seawater filter; 310. Third electric valve;

[0038] 400. Water pump;

[0039] 500. Shellfish traps;

[0040] 600. Ejector;

[0041] 700, First electric valve;

[0042] 800. Check valve;

[0043] 900. Sewage pipe; 910. Second electric valve. Detailed Implementation

[0044] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0045] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0046] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0047] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0048] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0049] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0050] This application provides a filtration and cleaning system, such as... Figure 1 As shown, the filtration and cleaning system includes a water tank 100, a circulation pipeline 200, a seawater filter 300, a water pump 400, a shellfish trap 500, and an ejector 600. The two ends of the circulation pipeline 200 are connected to the outlet and inlet of the water tank 100, respectively. The seawater filter 300, the water pump 400, and the shellfish trap 500 are arranged sequentially on the circulation pipeline 200 along the flow direction of the fluid. The ejector 600 has a first inlet, a second inlet, and a liquid outlet. The first inlet is connected to the outlet of the water pump 400, the second inlet is connected to the drain outlet of the seawater filter 300, and the liquid outlet is connected to the inlet of the water tank 100.

[0051] The filtration and cleaning system has a filtration state and a jet backwash state. When in the filtration state, the fluid in the pool 100 flows back into the pool 100 after being filtered by the seawater filter 300, the water pump 400, and the shellfish trap 500. When in the jet backwash state, part of the pressurized fluid flowing through the water pump 400 flows into the jet ejector 600 and generates negative pressure in the jet ejector 600, so that the fluid flowing through the seawater filter 300 returns to the seawater filter 300 and carries the dirt through the drain outlet, the second inlet, and the liquid outlet to the pool 100.

[0052] The aforementioned filtration and cleaning system for nuclear power plants connects the two ends of the circulation pipeline 200 to the outlet and inlet of the water tank 100, respectively, and arranges the seawater filter 300, water pump 400, and shellfish trap 500 sequentially along the fluid flow direction in the circulation pipeline 200. In filtration mode, the fluid in pool 100 flows back to pool 100 after passing through seawater filter 300, water pump 400, and shellfish trap 500 in sequence, thereby filtering impurities such as marine organisms. The first inlet of jet jet 600 is connected to the outlet of water pump 400, the second inlet is connected to the drain outlet of seawater filter 300, and the liquid outlet is connected to the inlet of pool 100. In jet backwashing mode, part of the pressurized fluid after passing through water pump 400 flows into jet jet 600, creating a negative pressure in jet jet 600. That is, a pressure difference is formed between the drain outlet of seawater filter 300 and the second inlet of jet jet 600, so that the fluid after passing through seawater filter 300 returns to seawater filter 300 and carries the dirt back through the drain outlet, the second inlet, and the liquid outlet to pool 100 in sequence.

[0053] The filtration and cleaning system for nuclear power plants proposed in this application does not require additional high-pressure water sources or backwash water pumps 400. It solves the problem that traditional backwashing devices are difficult to install in small modular reactor nuclear power plants with compact structures and limited space. It not only ensures the safety of the cold source of the nuclear power plant, but also eliminates the need for nuclear-grade high-pressure pump sets, simplifies the system structure, and saves equipment layout space and costs.

[0054] It should be noted that during filtration, the fluid in pool 100 sequentially passes through seawater filter 300, water pump 400, and shellfish trap 500 before returning to pool 100. Figure 1 From a visual perspective, the fluid flows from left to right through the seawater filter 300 and the water pump 400. At this point, the impurities filtered by the seawater filter 300 are located on the left side of the filter screen. During jet backwashing, due to negative pressure, the fluid flowing through the seawater filter 300 reverses direction, i.e., in... Figure 1 From a visual perspective, the fluid flows from right to left, backwashing the filter screen of the seawater filter 300. That is, the fluid flows from the right side of the filter screen of the seawater filter 300 to the left side, thus washing the filter screen of the seawater filter 300. Under negative pressure, the flushed fluid carries the dirt into the jet injector 600.

[0055] In one embodiment, such as Figure 1As shown, a first electric valve 700 is installed on the pipeline connecting the outlet of the water pump 400 and the first inlet. The first electric valve 700 is controlled to open or close to switch the state of the filtration and cleaning system. By setting the first electric valve 700, the state switching of the filtration and cleaning system can be achieved by controlling the opening or closing of the first electric valve 700. When the first electric valve 700 is closed, all the pressurized fluid output by the water pump 400 enters the shellfish trap 500, and the system maintains the filtration state. The fluid passes through the seawater filter 300, the water pump 400, and the shellfish trap 500 in sequence to complete the filtration and return. When the first electric valve 700 is open, part of the pressurized fluid flows into the jet injector 600 and generates negative pressure. The system switches to the jet backwashing state, realizing the discharge of dirt from the seawater filter 300.

[0056] In one embodiment, such as Figure 1 As shown, a check valve 800 is installed on the pipeline connecting the inlet and outlet of the water tank 100. By installing the check valve 800, when the system is in filtration mode, the check valve 800 can prevent the fluid in the water tank 100 or the fluid filtered by the shellfish trap 500 from flowing back into the jet injector 600; when the system is in jet backwashing mode, the check valve 800 can prevent the fluid carrying dirt discharged from the outlet of the jet injector 600 from flowing back into the jet injector 600 or the seawater filter 300 due to pressure fluctuations, thereby ensuring that the dirty fluid generated by backwashing can be smoothly discharged into the water tank 100, avoiding dirt retention or secondary pollution of the equipment.

[0057] In this embodiment, the filtration and cleaning system also includes a drain bag. The check valve 800 is connected to the inlet of the water tank 100 through a drain pipe. The drain bag is located at the connection between the drain pipe and the inlet of the water tank 100 and is used to collect waste.

[0058] In other embodiments, the filtration and cleaning system also includes a sludge tank, and a check valve 800 is connected to the sludge tank through a drain pipe. The fluid that has been filtered through the sludge tank flows back to the water tank 100 to participate in the circulation.

[0059] In one embodiment, the filtration and cleaning system further includes a controller electrically connected to a first electric valve 700 and a check valve 800, the controller being used to control the opening or closing of the first electric valve 700 and the check valve 800.

[0060] In one embodiment, such as Figure 1As shown, the filtration and cleaning system also includes a drain pipe 900 and a second electric valve 910. The two ends of the drain pipe 900 are connected to the outlet of the shellfish trap 500 and the inlet of the pool 100, respectively. The second electric valve 910 is installed on the drain pipe 900. When in filtration mode or jet backwashing mode, the second electric valve 910 is configured to be closed. The filtration and cleaning system also includes a trap backwashing mode. When in trap backwashing mode, the second electric valve 910 is configured to be open.

[0061] By adding a sewage discharge pipe 900 and installing a second electric valve 910 on the sewage discharge pipe 900, when the system is in filtration or jet backwashing mode, the second electric valve 910 is closed, ensuring that the fluid completes filtration or backwashing of the seawater filter 300 according to the preset path; when it is necessary to backwash the shellfish trap 500, the second electric valve 910 is opened, and the fluid in the shellfish trap 500 can carry the dirt directly back to the water tank 100 through the sewage discharge pipe 900, so that the shellfish trap 500 can be cleaned without the need for additional backwashing equipment.

[0062] In one embodiment, such as Figure 1 As shown, the filtration and cleaning system also includes a third electric valve 310. The third electric valve 310 is located on the pipeline connecting the second inlet and the drain outlet of the seawater filter 300. When in filtration mode, the third electric valve 310 is closed, and when in jet backwashing mode, the third electric valve 310 is open.

[0063] Specifically, both the second electric valve 910 and the third electric valve 310 are electrically connected to the controller.

[0064] In one embodiment, such as Figure 1 As shown, the jet ejector 600 includes a venturi tube with two axially oriented openings: a first inlet and a liquid outlet. The venturi tube wall has a through-hole connecting the outside to the internal space of the venturi tube, which serves as a second inlet. With the two axially oriented ends of the venturi tube serving as the first inlet and the liquid outlet, and the through-hole in the tube wall serving as the second inlet, when the pressurized fluid output from the water pump 400 flows into the venturi tube from the first inlet, the flow velocity changes along the axial direction due to the tube structure, creating a negative pressure at the through-hole (second inlet) in the tube wall, thus forming a pressure difference with the drain outlet of the seawater filter 300.

[0065] In one embodiment, the filtration and cleaning system further includes a pressure detection component disposed on the seawater filter 300. The pressure detection component is used to detect the pressure difference between the inlet and outlet of the seawater filter 300. As the amount of dirt trapped inside the seawater filter 300 gradually increases, the pressure difference between the inlet and outlet of the seawater filter 300 will increase accordingly. By installing a pressure detection component on the seawater filter 300, this pressure difference change can be captured, providing a basis for determining whether the seawater filter 300 needs to be backwashed.

[0066] In this embodiment, the pressure detection component includes at least two pressure gauges, with one pressure gauge at both the inlet and outlet of the seawater filter 300. In other embodiments, the pressure detection component may employ a structure that can detect changes in pressure differential.

[0067] In this embodiment, the pressure gauge is electrically connected to the controller, which receives the pressure data detected by the pressure gauge and makes a judgment.

[0068] In one embodiment, the filtration and cleaning system further includes a flow detection component disposed on the circulation pipeline 200, which is used to detect the fluid flow rate in the circulation pipeline 200. By installing a flow detection component on the circulation pipeline 200, the fluid flow state within the circulation pipeline 200 can be detected. In filtration mode, the flow detection component can provide timely feedback on the fluid filtration efficiency. If the flow rate drops abnormally, it can help determine whether there are problems such as blockage in the seawater filter 300 or the shellfish trap 500. In jet backwashing mode, the flow rate changes can be used to understand the fluid flow during backwashing and determine whether the backwashing operation has achieved the expected results.

[0069] In this embodiment, the flow detection component includes multiple flow meters, which are located in different areas of the circulation pipeline 200.

[0070] In this embodiment, the flow meter is electrically connected to the controller.

[0071] This application also provides a filtration and cleaning method for nuclear power plants, used in any of the filtration and cleaning systems described above, such as... Figure 1 and Figure 2 As shown, the filter cleaning method includes:

[0072] Connect the components of the water tank 100, circulation pipeline 200, seawater filter 300, water pump 400, shellfish trap 500, and jet generator 600.

[0073] When fluid needs to be filtered, the fluid is circulated in the circulation pipe 200, and after being filtered by the seawater filter 300, the water pump 400 and the shellfish trap 500, it flows back to the pool 100.

[0074] When the seawater filter 300 needs to be backwashed, part of the pressurized fluid flowing through the water pump 400 flows into the jet ejector 600 and generates negative pressure in the jet ejector 600, creating a pressure difference between the drain outlet and the second inlet, so that the fluid in the seawater filter 300 carrying the dirt is discharged into the water tank 100 in sequence through the drain outlet, the second inlet and the liquid outlet.

[0075] The aforementioned filtration and cleaning method for nuclear power plants, when fluid filtration is required, guides the fluid along the circulation pipeline 200, sequentially passing it through the seawater filter 300, water pump 400, and shellfish trap 500, effectively intercepting and filtering impurities in the fluid. When backwashing of the seawater filter 300 is required, a portion of the pressurized fluid output from the water pump 400 is guided into the ejector 600 to generate negative pressure. This pressure difference drives the discharge of contaminants from the seawater filter 300, completing the cleaning operation without the need for an additional high-pressure water source or backwash pump 400.

[0076] In one embodiment, such as Figure 1 and Figure 2 As shown, a pressure detection component is used to detect the actual pressure difference between the inlet and outlet of the seawater filter 300. When the pressure difference is greater than or equal to a preset pressure value, the filtration and cleaning system is switched from filtration mode to jet backwash mode. By using a pressure detection component to detect the actual pressure difference between the inlet and outlet of the seawater filter 300, when the actual pressure difference reaches the preset pressure value, it indicates that the accumulation of dirt inside the filter has affected the filtration efficiency. At this time, switching to jet backwash mode can remove dirt in time and avoid further clogging. Moreover, judging by pressure difference data eliminates the need for manual judgment, improving the accuracy of backwash timing control.

[0077] In one embodiment, the filtration and cleaning method further includes:

[0078] The first electric valve 700 is electrically connected to the controller. The controller is used to receive the pressure value detected by the pressure detection component and calculate the actual pressure difference. The controller determines the magnitude of the actual pressure difference and the preset pressure value.

[0079] If the pressure difference is greater than or equal to the preset pressure value, the controller controls the first electric valve 700 to open, switching from the filtration state to the jet backwashing state.

[0080] After the jet backwashing state is maintained for a preset time, the controller controls the first electric valve 700 to close, ending the backwashing operation.

[0081] By electrically connecting the first electric valve 700 to the controller, the controller receives the pressure value from the pressure detection component and calculates the actual pressure difference. Based on the comparison between the actual pressure difference and the preset pressure value, the controller automatically controls the opening and closing of the first electric valve 700, thus achieving automated control of system state switching. Simultaneously, by setting a preset time, the backwashing duration is controlled to ensure that the backwashing operation is sufficient and not excessive.

[0082] In this embodiment, the preset pressure value is 16 kPa and the preset time is 1 minute. In other embodiments, the preset pressure value and preset time are set according to the actual operation requirements.

[0083] It should be noted that during filtration, the controller closes the first electric valve 700, the second electric valve 910, the third electric valve 310, and the check valve 800. During jet backwashing, the controller simultaneously opens the first electric valve 700, the third electric valve 310, and the check valve 800, and closes the second electric valve 910. During trap backwashing, the controller simultaneously closes the first electric valve 700, the third electric valve 310, and the check valve 800, and opens the second electric valve 910.

[0084] In one embodiment, the filtration and cleaning method further includes:

[0085] After the first electric valve 700 is closed, parameters such as the inlet and outlet pressure difference of the seawater filter 300 and the flow rate of the circulation pipeline 200 are restored to their initial states. After backwashing, restoring the inlet and outlet pressure difference of the seawater filter 300 to its initial state indicates that the accumulated dirt inside the filter has been fully removed, and the filter's filtration capacity has returned to normal levels. Restoring the flow rate of the circulation pipeline 200 to its initial state indicates that the fluid flow in the circulation pipeline 200 is not obstructed by residual dirt, and the system has good flowability, providing a state guarantee for the system to stably perform its filtration function in the future.

[0086] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0087] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A filtration and cleaning system for nuclear power plants, characterized in that, The filtration and cleaning system includes: A water tank (100) and a circulation pipe (200), wherein the two ends of the circulation pipe (200) are respectively connected to the outlet and the inlet of the water tank (100); A seawater filter (300), a water pump (400), and a shellfish trap (500) are sequentially arranged on the circulation pipeline (200) along the direction of fluid flow; The jet ejector (600) has a first inlet, a second inlet and an outlet. The first inlet is connected to the outlet of the water pump (400), the second inlet is connected to the drain outlet of the seawater filter (300), and the outlet is connected to the inlet of the water tank (100). The filtration and cleaning system has a filtration state and a jet backwashing state. When in the filtration state, the fluid in the pool (100) flows back into the pool (100) after being filtered by the seawater filter (300), the water pump (400) and the shellfish trap (500). When in the jet backwashing state, part of the pressurized fluid flowing through the water pump (400) flows into the jet injector (600) and generates negative pressure in the jet injector (600), so that the fluid flowing through the seawater filter (300) returns to the seawater filter (300) and carries the dirt through the drain outlet, the second inlet and the liquid outlet to the water tank (100).

2. The filtration and cleaning system according to claim 1, characterized in that, A first electric valve (700) is provided on the pipeline connecting the outlet of the water pump (400) and the first inlet. The first electric valve (700) is controlled to open or close to switch the state of the filtration and cleaning system.

3. The filtration and cleaning system according to claim 1, characterized in that, A check valve (800) is installed on the pipeline connecting the inlet and outlet of the water tank (100).

4. The filtration and cleaning system according to claim 1, characterized in that, The filtration and cleaning system also includes a sewage pipe (900) and a second electric valve (910). The two ends of the sewage pipe (900) are respectively connected to the outlet of the shellfish trap (500) and the inlet of the pool (100). The second electric valve (910) is installed on the sewage pipe (900). When in the filtration state or the jet backwash state, the second electric valve (910) is configured to be closed; The filtration and cleaning system also has a trap backwash state, in which the second electric valve (910) is configured to open.

5. The filtration and cleaning system according to claim 1, characterized in that, The jet ejector (600) includes a venturi tube with two openings along the axial direction, namely the first inlet and the liquid outlet. The venturi tube has a through hole on its wall that connects the outside to the inside space of the venturi tube, and the through hole is the second inlet.

6. The filtration and cleaning system according to claim 1, characterized in that, The filtration and cleaning system also includes a pressure detection component installed on the seawater filter (300), which is used to detect the actual pressure difference between the inlet and outlet of the seawater filter (300).

7. The filtration and cleaning system according to claim 1, characterized in that, The filtration and cleaning system also includes a flow detection component disposed on the circulation pipeline (200), which is used to detect the fluid flow rate of the circulation pipeline (200).

8. A filtration and cleaning method for a nuclear power plant, used in the filtration and cleaning system as described in any one of claims 1-7, characterized in that, The filtration and cleaning method includes: Connect the components of the water tank (100), the circulation pipeline (200), the seawater filter (300), the water pump (400), the shellfish trap (500), and the jet generator (600); When fluid needs to be filtered, the fluid is circulated in the circulation pipeline (200), and after being filtered by the seawater filter (300), the water pump (400) and the shellfish trap (500), it flows back to the pool (100). When the seawater filter (300) needs to be backwashed, a portion of the pressurized fluid flowing through the water pump (400) flows into the jet injector (600) and generates a negative pressure in the jet injector (600), creating a pressure difference between the drain outlet and the second inlet, so that the fluid in the seawater filter (300) carrying dirt is discharged sequentially through the drain outlet, the second inlet and the liquid outlet to the water tank (100).

9. The filtration and cleaning method according to claim 8, characterized in that, The actual pressure difference between the inlet and outlet of the seawater filter (300) is detected using a pressure detection component; When the actual pressure difference is greater than or equal to the preset pressure value, the filtration and cleaning system for nuclear power plants is controlled to switch from the filtration state to the jet backwashing state.

10. The filtration and cleaning method according to claim 9, characterized in that, The filtration and cleaning method further includes: The first electric valve (700) is electrically connected to the controller. The controller is used to receive the pressure value detected by the pressure detection component and calculate the actual pressure difference. The controller determines the magnitude of the actual pressure difference and the preset pressure value. If the pressure difference is greater than or equal to the preset pressure value, the controller controls the first electric valve (700) to open, switching from the filtration state to the jet backwashing state; After the jet backwashing state is maintained for a preset time, the controller controls the first electric valve (700) to close, ending the backwashing operation.

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