Circulating water inlet system
A multi-stage filtration system with chemical treatment and automated cleaning addresses marine debris and organism blockages in nuclear power plant seawater intake, ensuring consistent water flow and reducing maintenance needs.
Patent Information
- Application Number
- CN202422358351.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-26
- Publication Date
- 2025-07-15
- Estimated Expiration
- 2034-09-26
AI Technical Summary
Marine organisms and debris are prone to accumulate at the water inlets of the open circulating water system, resulting in a decrease in the seawater flow and the inability to effectively take away the heat from the nuclear power plant, resulting in equipment damage and economic losses.
A circulating water inlet system is designed, including a sewage blocking net, a multi-stage sewage blocking gate and a reservoir. Combined with a sewage cleaner, a drum-shaped filter and a circulating water pump, it ensures the quality of seawater through multi-stage filtering and storing seawater, and provides emergency water sources when necessary to prevent clogging.
It effectively prevents marine organisms and debris from being blocked, maintains stable seawater flow, reduces equipment failures, reduces the risks of equipment damage and shutdown and maintenance, and improves the cooling efficiency and operating stability of nuclear power units.
Smart Images
Figure CN223096253U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of nuclear power, and particularly relates to a circulating water inlet system. Background Technique
[0002] Except for the part used for power generation by doing work, the heat generated by the nuclear power plant will be completely released into the surrounding water source and atmosphere. The circulating water system is a system that uses the water source around the nuclear power plant to take away the remaining heat, avoiding excessive heat accumulation inside the nuclear power plant. In the circulating water system, the open circulating water uses seawater as the cold source, supplies the seawater to the condenser and then discharges it into the water source. Currently, all the nuclear power plants built in China are coastal nuclear power plants, so the open circulating water system is mainly adopted.
[0003] However, due to the complex situation inside the ocean, there are many plankton and sundries inside the ocean. The plankton and sundries are easy to accumulate at the inlet of the open circulating water system, resulting in a small flow rate of seawater entering the open circulating water system, being unable to take away the heat generated by the nuclear power plant, causing failures in the nuclear power plant, ultimately leading to damage to the equipment of the nuclear power plant, requiring shutdown for maintenance, and causing economic losses. Content of the Utility Model
[0004] The purpose of the utility model is to provide a circulating water inlet system to solve the problem that marine organisms and sundries may cause blockage of the circulating water inlet system in the prior art.
[0005] To achieve this purpose, the utility model adopts the following technical solutions: The utility model provides a circulating water inlet system, including an inlet water flow channel. A trash screen is installed at the front end of the inlet water flow channel. A first trash rack and a second trash rack are sequentially installed on the inlet water flow channel. A water storage tank is connected to the rear end of the second trash rack. A gate is installed at the water outlet of the water storage tank. A third trash rack is installed on the inlet water flow channel behind the gate. A drum strainer is installed at the rear end of the inlet water flow channel. A circulating water pump is installed behind the drum strainer. A switch valve is installed behind the circulating water pump. The switch valve is connected to the nuclear power unit. The filtering gaps between the first trash rack and the second trash rack gradually decrease. The filtering gaps of the second trash rack and the third trash rack are the same. A dirt cleaning machine is installed on the first trash rack, the second trash rack, and the third trash rack, and the dirt cleaning machine can clean dirt; Sodium hypochlorite is added into the inlet water flow channel at the first trash rack.
[0006] Preferably, a differential pressure sensor is installed on the drum strainer. The differential pressure sensor is electrically connected to a controller, and the controller is electrically connected to the switch valve.
[0007] Preferably, a liquid level sensor is installed in the water storage tank. The liquid level sensor is electrically connected to the controller.
[0008] Preferably, the trash screen is a soft alloy mesh, and polyethylene floats are arranged on the trash screen.
[0009] Preferably, first bars are arranged at equal intervals in the first trash rack, the interval between the first bars is 200 mm, and the first bars are vertically inserted at the bottom of the water inlet channel.
[0010] Preferably, second bars are arranged at equal intervals in the second trash rack and the third trash rack, the interval between the second bars is 50 mm, and the second bars are vertically inserted at the bottom of the water inlet channel.
[0011] Preferably, the water inlet channel includes six groups, and adjacent two groups of the water inlet channels are connected to a group of the drum-shaped filter screen.
[0012] Preferably, the water inlet channel is communicated with the nuclear power unit through a guiding channel, the guiding channels are communicated through an auxiliary channel, and an isolation valve is installed on the auxiliary channel.
[0013] Preferably, a steel gate is installed between the first trash rack and the second trash rack.
[0014] Beneficial effects: By adding a reservoir in the water inlet channel, the sea waves can be eliminated, the impact of seawater on the components in the water inlet channel can be reduced, and seawater can be stored. When blockage occurs and shutdown maintenance is required, the reservoir can provide seawater for the nuclear power unit. Different sizes of impurities in seawater are filtered in a graded manner by the first trash rack, the second trash rack and the third trash rack. At the same time, the cleaning machine will remove the sundries on the first trash rack, the second trash rack and the third trash rack to keep the first trash rack, the second trash rack and the third trash rack clean, so that less impurities of the seawater entering the nuclear power unit can be avoided from being blocked. After the seawater is finally filtered by the drum-shaped filter screen, the seawater is filled into the nuclear power unit by the circulating water pump through the switching valve to cool the nuclear power unit. Description of the Drawings
[0015] Figure 1 is a schematic structural diagram of the circulating water inlet system of the present utility model.
[0016] In the figure: 1. Trash screen; 2. Water inlet channel; 3. First trash rack; 4. Second trash rack; 5. Third trash rack; 6. Reservoir; 7. Gate; 8. Drum-shaped filter screen; 9. Circulating water pump; 10. Switching valve; 11. Differential pressure sensor; 12. Liquid level sensor; 13. Guiding channel; 14. Auxiliary channel; 15. Isolation valve; 16. Steel gate; 17. Controller. Detailed Embodiment
[0017] The present utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present utility model, rather than limiting the present utility model. In addition, it should be noted that for the convenience of description, only the parts related to the present utility model are shown in the drawings, rather than all the structures.
[0018] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.
[0019] In the present utility model, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "above the", and "on the" of the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "below the", and "under the" of the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is lower than that of the second feature.
[0020] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "right", etc. are based on the orientation or positional relationships shown in the drawings. It is only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.
[0021] Under the prior art, seawater directly enters the nuclear power unit, and blockages often occur, resulting in a reduction in the seawater flow rate entering the nuclear power unit. Manual shutdown is required for cleaning, which will lead to insufficient seawater supply and further cause failures in the nuclear power unit.
[0022] To solve the above problems, as Figure 1As shown in the figure, the utility model provides a circulating water inlet system, which includes an inlet water flow channel 2. A trash screen 1 is installed at the front end of the inlet water flow channel 2. A first trash rack 3 and a second trash rack 4 are successively installed on the inlet water flow channel 2. A water storage tank 6 is connected to the rear end of the second trash rack 4. A gate 7 is installed at the water outlet of the water storage tank 6. A third trash rack 5 is installed on the inlet water flow channel 2 behind the gate 7. A drum filter 8 is installed at the rear end of the inlet water flow channel 2. A circulating water pump 9 is installed behind the drum filter 8. A switching valve 10 is installed behind the circulating water pump 9. The switching valve 10 is connected to the nuclear power unit. The filtering gaps between the first trash rack 3 and the second trash rack 4 gradually decrease. The filtering gaps of the second trash rack 4 and the third trash rack 5 are the same. A cleaning machine is installed on the first trash rack 3, the second trash rack 4 and the third trash rack 5. The cleaning machine can detect the pressure difference on both sides of the trash rack according to its own pressure sensor, and then perform automatic cleaning to clean the dirt on the first trash rack 3, the second trash rack 4 and the third trash rack 5. In order to reduce the attachment and reproduction of various marine organisms on the cooling water pipes and condensers in the nuclear power unit, increase the flow area to improve the water conveyance capacity, and improve the cooling efficiency of the condenser, sodium hypochlorite is added to the sea water at the first trash rack 3, and the continuous dosing method is adopted to kill the organisms in the sea water.
[0023] The sea water from the outside enters the inlet water flow channel 2 through the trash screen 1. The trash screen 1 can filter large-volume foreign objects. After the sea water enters the inlet water flow channel 2, it successively passes through the first trash rack 3 and the second trash rack 4. The first trash rack 3 and the second trash rack 4 can filter smaller-volume foreign objects in the sea water. Finally, they will all flow into the water storage tank 6. The water storage tank 6 can eliminate the waves of the sea water and reduce the impact of the sea water on the components of the circulating water inlet system. A third trash rack 5 is installed at the water outlet of the water storage tank 6, which can further filter fine particles. When the components on the inlet water flow channel 2 are blocked and the water flow is insufficient, the water in the water storage tank 6 can enter the nuclear power unit along the inlet water flow channel 2 as cooling water to make up for the problem of insufficient cooling water source.
[0024] In order to prevent debris or organisms from accumulating on the first trash rack 3, the second trash rack 4 and the third trash rack 5, a cleaning machine is installed. The main principle of the cleaning machine is to drive the inserting teeth to move through a chain. The inserting teeth move along the height direction of the first trash rack 3, the second trash rack 4 and the third trash rack 5, and at the same time lift the debris upward for easy cleaning by personnel. The inserting teeth move in a circular motion driven by the chain, and then the inserting teeth continue to return to the bottom of the water driven by the chain. The above working process of the cleaning machine is the prior art and will not be elaborated here. This can keep the first trash rack 3, the second trash rack 4 and the third trash rack 5 clean, avoid accumulation, and increase the sea water flow. The circulating water pump 9 continuously pumps the water in the water storage tank 6 into the pump group. The sea water in the middle needs to be finally filtered by the drum filter and then enters the nuclear power unit to reduce the probability of blockage.
[0025] A differential pressure sensor 11 is installed on the drum-shaped filter screen 8. The differential pressure sensor 11 is electrically connected to the controller 17, and the controller 17 is electrically connected to the switching valve 10.
[0026] A liquid level sensor 12 is installed in the reservoir 6. The liquid level sensor 12 is electrically connected to the controller 17, and the controller 17 is electrically connected to the switching valve 10. However, when the liquid level in the reservoir 6 is too low, the controller 17 controls the circulation water pump 9 to shut down to avoid idling. When the circulation water pump 9 stops, the reservoir 6 can be used as an emergency water source to gain time for removing blockages.
[0027] The trash rack 1 used in the present utility model is a soft net made of alloy material, which can prevent pollution, corrosion, and attachment of marine organisms. The diameter of the wire of the mesh is 5 mm, and the mesh size is 120 mm × 120 mm. Polyethylene floating balls are arranged on the trash rack 1, which can strengthen the support of the trash rack 1 and improve the strength of the trash rack 1.
[0028] First grid bars are arranged at equal intervals in the first trash rack 3. The spacing between the first grid bars is 200 mm. The first grid bars are vertically inserted at the bottom of the water inlet flow channel 2 to intercept large floating objects. Sacrificial anode blocks and coatings are used for combined anti-corrosion protection on the first grid bars to reduce the attachment and reproduction of various marine organisms on the cooling water pipes and condensers and increase the water flow capacity.
[0029] Second grid bars are arranged at equal intervals in the second trash rack 4. The spacing between the second grid bars is 50 mm. The second grid bars are vertically inserted at the bottom of the water inlet flow channel 2. A second cleaning machine is installed on the second trash rack 4, which can intercept small pieces of garbage or floating objects to improve the filtration degree of seawater.
[0030] The water inlet flow channel 2 of the present utility model includes six groups, and adjacent two groups of water inlet flow channels 2 are connected to a group of drum-shaped filter screens 8. Arranging multiple groups of water inlet flow channels 2 can quickly supplement the water in the reservoir 6 and prevent the liquid level in the reservoir 6 from dropping rapidly.
[0031] Every two groups of water inlet flow channels 2 are connected to the nuclear power unit through the guiding flow channel 13. The guiding flow channels 13 are connected to each other through the auxiliary flow channel 14. An isolation valve 15 is installed on the auxiliary flow channel 14. When the temperature of the nuclear power unit is too high, the isolation valve 15 therein will be opened, so that Figure 1 the circulating water pump 9 in the middle position is started, and water is supplemented into the guiding flow channel 13 through the auxiliary flow channel 14 to increase the water inlet flow rate and improve the cooling capacity. If the temperature of the nuclear power unit becomes lower, the circulating water pump 9 in the middle position in the figure is shut down, and the isolation valve 15 is closed to maintain low-flow operation.
[0032] A steel gate 16 is installed between the first trash rack 3 and the second trash rack 4, which can close the water inlet flow channel 2.
[0033] Obviously, the above embodiments of the present utility model are merely examples for clearly illustrating the present utility model, rather than limitations on the implementation manners of the present utility model. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present utility model. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present utility model shall be included within the protection scope of the claims of the present utility model.
Claims
1. A circulating water inlet system, characterized in that, It includes an inlet water passage (2), a trash rack (1) is installed at the front end of the inlet water passage (2), a first trash screen (3) and a second trash screen (4) are successively installed on the inlet water passage (2), a reservoir (6) is connected to the rear end of the second trash screen (4), a gate (7) is installed at the water outlet of the reservoir (6), a third trash screen (5) is installed on the inlet water passage (2) behind the gate (7), a drum filter (8) is installed at the rear end of the inlet water passage (2), a circulating water pump (9) is installed behind the drum filter (8), a switch valve (10) is installed behind the circulating water pump (9), the switch valve (10) is connected to a nuclear power unit, the filtering gap gradually decreases from the first trash screen (3) to the second trash screen (4), the filtering gaps of the second trash screen (4) and the third trash screen (5) are the same, a cleaning machine is installed on the first trash screen (3), the second trash screen (4) and the third trash screen (5), and the cleaning machine can clean dirt; sodium hypochlorite is added into the inlet water passage (2) at the first trash screen (3).
2. The circulating water inlet system according to claim 1, wherein A differential pressure sensor (11) is installed on the drum filter (8), the differential pressure sensor (11) is electrically connected to a controller (17), and the controller (17) is electrically connected to the switch valve (10).
3. The circulating water inlet system according to claim 2, characterized in that, A liquid level sensor (12) is installed in the reservoir (6), and the liquid level sensor (12) is electrically connected to the controller (17).
4. The circulating water inlet system according to claim 1, wherein The trash rack (1) is a soft net made of alloy material, and polyethylene floating balls are arranged on the trash rack (1).
5. The circulating water inlet system according to claim 1, characterized in that, First grid bars are arranged at equal intervals in the first trash screen (3), the spacing of the first grid bars is 200 mm, and the first grid bars are vertically inserted into the bottom of the inlet water passage (2).
6. The circulating water inlet system according to claim 1, characterized in that, Second grid bars are arranged at equal intervals in the second trash screen (4) and the third trash screen (5), the spacing of the second grid bars is 50 mm, and the second grid bars are vertically inserted into the bottom of the inlet water passage (2).
7. The circulating water inlet system according to claim 1, characterized in that The inlet water passage (2) includes six groups, and adjacent two groups of the inlet water passage (2) are connected to a group of drum filters (8).
8. The circulating water inlet system according to claim 7, wherein, The inlet water passage (2) is communicated with the nuclear power unit through a guiding water passage (13), the guiding water passages (13) are communicated with each other through an auxiliary water passage (14), and an isolation valve (15) is installed on the auxiliary water passage (14).
9. The circulating water inlet system according to claim 1, characterized in that, A steel gate (16) is installed between the first trash screen (3) and the second trash screen (4).