A conventional island closed loop cooling water system

Abstract

The utility model discloses a conventional island closed circuit cooling water system, including cooling water pipeline, heat exchange space and the heat exchanger of setting in heat exchange space, cooling water pipeline passes through heat exchanger, still include: first valve and second valve, the inlet end of first valve is connected to first water source, the inlet end of second valve is connected to second water source, and the outlet of first valve and second valve is all connected to the inlet of heat exchange space, third valve and fourth valve, and the inlet of third valve and fourth valve is all connected to the outlet of heat exchange space. The utility model embodiment through with first water source connection first valve and second water source connection second valve, when first water source can not supply during the overhaul of unit, can access second water source, and through third valve or fourth valve, the flowing first water source or second water source can take away the heat of conventional island closed circuit cooling water system, can ensure the water temperature stability of conventional island closed circuit cooling water system.

Description

Technical Field

[0001] This utility model relates to the technical field of closed-loop cooling water systems for conventional islands in nuclear power plants, and particularly to a closed-loop cooling water system for conventional islands. Background Technology

[0002] SRI is a conventional island closed-loop cooling water system. The main function of SRI is to cool equipment in the BOP and MX buildings that require cooling, such as pumps, motors, and heat exchangers. The SRI system transfers the heat absorbed from the equipment to the auxiliary cooling water system (SEN) through the heat exchanger. The seawater in the auxiliary cooling water system (SEN) absorbs the heat from the SRI system at the heat exchanger and releases the heat into the sea with the seawater flow.

[0003] During a generator unit overhaul, a crucial activity is the overall generator airtightness test. Before this test, it's essential to ensure the generator sealing oil system (GHE) is operational and the oil temperature is stable. This requires the SRI system to effectively dissipate the heat generated by the GHE. However, the auxiliary cooling water system (SEN) and its upstream CRF circulating water system (which supplies seawater to the SEN) are often not operational in a timely manner due to ongoing maintenance work. This necessitates waiting until the SEN and CRF systems are started before the overall generator airtightness test can be conducted, hindering the progress of the conventional island unit overhaul and extending the overhaul period. Utility Model Content

[0004] The purpose of this invention is to provide a conventional island closed-loop cooling water system, which aims to solve the problem that the existing SRI system cannot remove the heat generated by the generator sealing oil system in time, thus extending the overhaul period.

[0005] This utility model provides a conventional island closed-loop cooling water system, comprising: cooling water pipelines, a heat exchange space, and a heat exchanger disposed within the heat exchange space, wherein the cooling water pipelines pass through the heat exchanger. The conventional island closed-loop cooling water system further comprises: The first valve and the second valve are connected, with the inlet end of the first valve connected to the first water source and the inlet end of the second valve connected to the second water source. The outlet ends of both the first valve and the second valve are connected to the inlet of the heat exchange space. The inlet ends of the third valve and the fourth valve are both connected to the outlet of the heat exchange space.

[0006] Optionally, the first water source is a natural water body, and the second water source is an artificial water body.

[0007] Optionally, the inlet of the heat exchange space is located at the bottom of the heat exchange space, and the outlet of the heat exchange space is located at the top of the heat exchange space.

[0008] Optionally, it also includes a control valve and a connecting pipeline, wherein one end of the control valve is connected to the inlet end of the second valve through the connecting pipeline, and the other end of the control valve is connected to the second water source.

[0009] Optionally, the connecting pipe is a flexible metal hose.

[0010] Optionally, the control valve is an electrically controlled valve.

[0011] Optionally, the first valve and the fourth valve are electrically operated isolation valves.

[0012] Optionally, the second valve is a steam trap, and the third valve is an air vent valve.

[0013] Optionally, it also includes a differential pressure detection device, wherein the first sampling point of the differential pressure detection device is located between the inlet of the heat exchange space and the junction of the first valve and the second valve; and the second sampling point of the differential pressure detection device is located between the outlet of the heat exchange space and the junction of the third valve and the fourth valve.

[0014] Optionally, it also includes a water temperature measuring device for measuring the temperature of the cooling water pipe after passing through the heat exchanger.

[0015] This utility model discloses a conventional island closed-loop cooling water system, including cooling water pipelines, a heat exchange space, and a heat exchanger disposed within the heat exchange space. The cooling water pipelines pass through the heat exchanger. The conventional island closed-loop cooling water system further includes: a first valve and a second valve, the inlet end of the first valve being connected to a first water source, the inlet end of the second valve being connected to a second water source, and the outlet ends of both the first and second valves being connected to the inlet of the heat exchange space; a third valve and a fourth valve, the inlet ends of both the third and fourth valves being connected to the outlet of the heat exchange space. In this embodiment, by connecting the first valve to the first water source and the second valve to the second water source, when the first water source is unavailable during unit overhaul, the second water source can be connected; or, when the second water source is unavailable during unit overhaul, the first water source can be connected, and water can be discharged through the third or fourth valve. The flowing first or second water source can carry away the heat from the conventional island closed-loop cooling water system, ensuring stable water temperature. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of a conventional island closed-loop cooling water system provided by this utility model.

[0018] Explanation of the markings in the image: 10. Conventional island closed-loop cooling water system; 100. Heat exchange space; 1000. Heat exchanger; 101. First valve; 102. Second valve; 103. First water source; 104. Second water source; 105. Third valve; 106. Fourth valve; 107. Control valve; 108. Connecting pipeline; 109. Differential pressure detection device; 110. Water temperature measuring device. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0020] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0021] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0022] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0023] Please see Figure 1This utility model provides a conventional island closed-loop cooling water system 10, including a cooling water pipeline, a heat exchange space 100, and a heat exchanger 1000 disposed in the heat exchange space 100. The cooling water pipeline passes through the heat exchanger 1000. The conventional island closed-loop cooling water system 10 further includes: a first valve 101 and a second valve 102, the inlet end of the first valve 101 being connected to a first water source 103, the inlet end of the second valve 102 being connected to a second water source 104, and the outlet ends of the first valve 101 and the second valve 102 being connected to the inlet of the heat exchange space 100; a third valve 105 and a fourth valve 106, the inlet ends of the third valve 105 and the fourth valve 106 being connected to the outlet of the heat exchange space 100.

[0024] In this embodiment, the present invention connects the first valve 101 to the first water source 103 and the second valve 102 to the second water source 104. When the first water source 103 cannot supply water during the unit overhaul, the second water source 104 can be connected; or, when the second water source 104 cannot supply water during the unit overhaul, the first water source 103 can be connected, and water can be discharged through the third valve 105 or the fourth valve 106. The flowing first water source 103 or the second water source 104 can carry away the heat of the conventional island closed-loop cooling water system 10, which can ensure the stability of the water temperature of the conventional island closed-loop cooling water system 10.

[0025] In summary, the solution proposed in this embodiment is not affected by the maintenance work of the auxiliary cooling water system (SEN) and the CRF circulating water system. It can absorb the heat of the heat exchanger 1000 and ensure that the overall airtightness test of the generator can be performed in advance even if the CRF system and SEN system are not restored. If the airtightness test fails, there is also sufficient time to deal with the leak point, which greatly shortens the overhaul time of the conventional island unit.

[0026] In a specific embodiment, the first water source 103 is a natural water body, and the second water source 104 is an artificial water body. The first water source 103 is a natural water body, such as seawater or a river. Natural water bodies have advantages such as abundant water volume and relatively low water intake costs. When the unit is operating normally and the water quality and quantity of the natural water body meet the requirements, it can serve as the main cooling water source. The connection method of the first water source 103 is: the inlet end of the first valve 101 is connected to the natural water body through a pipe. The second water source 104 is an artificial water body, such as a reservoir built by the factory itself. Artificial water bodies have characteristics such as high fluidity, controllable water quality, and high water supply stability. When the natural water body cannot meet the system requirements (such as when the intake of natural water is limited during a major overhaul of the unit, or when the water quality deteriorates or the water volume is insufficient), it can serve as a backup cooling water source to replace the natural water body for cooling the heat exchanger 1000.

[0027] In addition, the conventional island closed-loop cooling water system 10 also includes a system high-level water tank and a water pump, combined with Figure 1 As shown, SRI001BA is the system high-level water tank, and SRI101 / 201 / 301PO is the water pump. The system high-level water tank can provide suction head for the water pump and fill and replenish water for the entire cooling water system.

[0028] Furthermore, the inlet of the heat exchange space 100 is located at the bottom of the heat exchange space 100, and the outlet of the heat exchange space 100 is located at the top of the heat exchange space 100. In this embodiment, taking the second water source 104 as an example, the second water source 104 is connected to the second valve 102 through a pipe, and the outlet end of the second valve 102 is connected to the inlet at the bottom of the heat exchange space 100. When the second water source 104 is needed, the second valve 102 is opened, and the second water source 104 will enter the heat exchange space 100 from the bottom of the heat exchanger 1000. A third valve 105 is provided at the top of the heat exchange space 100. After the cooling water completes heat exchange within the heat exchange space 100, it will flow out from the third valve 105 at the top.

[0029] Since the inlet of the heat exchange space 100 is at the bottom and the outlet is at the top, when the second water source 104 enters from the bottom, the water will naturally rise to fill the entire heat exchange space 100. Because water flows from low to high under the action of gravity until it fills the entire heat exchange space 100, this design can ensure that the heat exchanger 1000 is always in a state of being filled with water, thus ensuring the cooling efficiency of the heat exchanger 1000.

[0030] Furthermore, the conventional island closed-loop cooling water system 10 also includes a control valve 107 and a connecting pipe 108. One end of the control valve 107 is connected to the inlet end of the second valve 102 through the connecting pipe 108, and the other end of the control valve 107 is connected to the second water source 104.

[0031] In this embodiment, the second water source 104 is connected as follows: the other end of the control valve 107 is connected to an artificial water body via a pipe. One end of the control valve 107 is connected to the inlet end of the second valve 102 via a connecting pipe 108. The control valve 107 can regulate the access of the second water source 104. Under normal operating conditions, if the first water source 103 (natural water body) can meet the cooling requirements of the conventional island closed-loop cooling water system 10, the control valve 107 can be closed to prevent unnecessary access of the second water source 104. When the natural water body cannot be accessed, the operator can open the control valve 107 to allow the second water source 104 to smoothly enter the second valve 102 through the connecting pipe 108, and then access the heat exchange space 100 to provide cooling water for the heat exchange space.

[0032] In a specific embodiment, the connecting pipe 108 is a flexible metal hose. One end of the flexible metal hose is tightly connected to the outlet end of the control valve 107, and the other end is connected to the inlet end of the second valve 102. A quick-connect coupling is used at the connection point to ensure a secure and well-sealed connection, preventing cooling water leakage at the connection. The quick-connect coupling is matched to the interfaces of the flexible metal hose, control valve 107, and second valve 102, and is fixed by means of threaded connection or flange connection, ensuring the reliability and stability of the connection.

[0033] Furthermore, connect one end of the metal hose to the quick connector at one end of the control valve 107, slowly open the control valve 107 to flush the metal hose, and close the control valve 107 when the water flowing out from the second water source 104 is clear and free of impurities to prevent impurities in the metal hose from entering the heat exchanger 1000.

[0034] In a specific embodiment, the control valve 107 is an electrically controlled valve 107. The electrically controlled valve 107 includes an electrically driven actuator and a valve. The electrically driven actuator is the power source for the electrically controlled valve 107 and typically consists of a motor, a reducer, a position sensor, and a control circuit. The motor provides power, and the reducer converts the high-speed rotary motion into a low-speed, high-torque output to drive the opening and closing of the valve. The position sensor monitors the valve's opening position in real time and feeds the signal back to the control circuit. The control circuit then precisely controls the operation of the motor based on the received control signal and position feedback signal.

[0035] Furthermore, the first valve 101 and the fourth valve 106 are electrically operated isolation valves.

[0036] Electric isolation valves possess rapid response capabilities. During testing, when the fluid passage needs to be quickly shut off or opened, the electric drive unit can complete the action in a short time, effectively preventing production accidents caused by fluid leakage or supply interruption. Simultaneously, electric isolation valves offer precise control performance. Through an advanced control system, the valve opening can be precisely adjusted, achieving accurate control of parameters such as fluid flow rate and pressure.

[0037] In a specific embodiment, the first water source 103 is connected to the first valve 101 via a pipe, and the outlet end of the first valve 101 is connected to the inlet at the bottom of the heat exchange space 100. When the first water source 103 is used, the first valve 101 is opened, and the first water source 103 enters the heat exchange space 100 from the bottom of the heat exchanger 1000. A fourth valve 106 is provided at the top of the heat exchange space 100. After the cooling water completes heat exchange within the heat exchange space 100, it flows out from the fourth valve 106 at the top.

[0038] When heat exchange using the first water source 103 is required, the operator sends an opening command to the first valve 101 through the control system. The electric actuator drives the first valve 101 to gradually open, and the first water source 103 begins to flow into the heat exchange space 100 through the pipe. During the opening process, the opening degree of the first valve 101 can be adjusted according to actual needs to control the flow rate of the first water source 103. At the same time, the system monitors parameters such as pressure and temperature within the heat exchange space 100 in real time to ensure normal operation. After the heat exchange operation is completed, the operator closes the first valve 101 through the control system, cutting off the supply of the first water source 103. Subsequently, the fourth valve 106 will also automatically close after completing its drainage task, and the system returns to its initial state, ready for the next use.

[0039] Furthermore, the second valve 102 is a drain valve, and the third valve 105 is an air vent valve. In this embodiment, when the second water source 104 is not needed, the second valve 102 (drain valve) is in a closed state, isolating the second water source 104 from the heat exchange space 100, preventing the second water source 104 from entering the heat exchange space 100 when not needed; the third valve 105 (air vent valve) is also in a closed state, avoiding excessive gas exchange between the heat exchange space 100 and the outside, and maintaining a relatively stable environment inside the conventional island closed-loop cooling water system 10.

[0040] When the second water source 104 is needed for heat exchange, the operator will open the second valve 102 (steam trap). The steam trap can automatically adjust its opening degree according to factors such as pressure, temperature, and fluid state within the pipeline. Upon opening, due to the pressure on the second water source 104 side, the second water source 104 begins to flow into the heat exchange space 100 along the pipeline. The steam trap can gradually adjust its opening degree according to system requirements to ensure that the second water source 104 enters the heat exchange space 100 at an appropriate flow rate. For example, if the heat exchange space 100 has a small demand for the second water source 104, the steam trap will only open at a certain angle, limiting the flow rate of the second water source 104; if the demand is large, the opening degree will be increased accordingly to ensure sufficient second water source 104 enters.

[0041] The second water source 104 enters the heat exchange space 100 from the bottom of the heat exchanger 1000. Bottom-entry ensures the heat exchanger 1000 is always filled with water, improving heat exchange efficiency. After entering the heat exchange space 104, the second water source 104 exchanges heat with the heat medium within it. During this process, the second water source 104 absorbs heat from the heat medium, gradually increasing its own temperature; conversely, the heat medium releases heat, gradually decreasing its temperature. As the heat exchange continues, the cooling water (i.e., the second water source 104 after heat exchange) rises continuously within the heat exchange space 100. Because hot water is less dense than cold water, the cooling water gradually accumulates at the top of the heat exchange space 100. When the cooling water in the heat exchange space 100 reaches a certain volume, it needs to be drained to ensure the continuous operation of the heat exchange process.

[0042] At this time, the third valve 105 (exhaust valve) will open, and the cooling water will flow out of the heat exchange space 100 from the third valve 105 at the top under the action of its own gravity and system pressure.

[0043] Furthermore, the conventional island closed-loop cooling water system 10 also includes a differential pressure detection device 109. The first sampling point of the differential pressure detection device 109 is located between the inlet of the heat exchange space 100 and the junction of the first valve 101 and the second valve 102; the second sampling point of the differential pressure detection device 109 is located between the outlet of the heat exchange space 100 and the junction of the third valve 105 and the fourth valve 106.

[0044] In this embodiment, the differential pressure detection device 109 operates based on the fundamental principle of fluid pressure difference measurement. It collects cooling water pressure values ​​before the inlet and after the outlet of the heat exchange space 100 through a first sampling point and a second sampling point, respectively. The pressure signals collected at these two sampling points are transmitted to the sensor in the differential pressure detection device 109. The pressure sensing element inside the sensor converts the pressure signals into electrical signals. These electrical signals are amplified, filtered, and then transmitted to a microprocessor for analysis and calculation. The microprocessor calculates the pressure difference between the two sampling points, i.e., the differential pressure, according to a pre-set algorithm. This differential pressure reflects the resistance encountered by the cooling water during its flow within the heat exchange space 100, and the degree of influence of the heat exchange space 100 on the cooling water flow.

[0045] Furthermore, timely detection of pressure differential anomalies can prevent equipment failures. For example, if the pressure differential continues to increase and is not addressed promptly, it may damage the heat exchanger 1000 due to excessive pressure. In addition, pressure differential anomalies can also affect the normal operation of other equipment connected to the conventional island closed-loop cooling water system 10, such as water pumps potentially being damaged due to overload. Through the real-time monitoring and early warning functions of the pressure differential detection device 109, operators can take appropriate measures before equipment failure occurs, such as cleaning the heat exchanger 1000 or adjusting valve openings, thereby improving the reliability and safety of the system.

[0046] Furthermore, the conventional island closed-loop cooling water system 10 also includes a water temperature measuring device 110, which is used to measure the temperature of the cooling water pipes after passing through the heat exchanger 1000. In this embodiment, in the conventional island closed-loop cooling water system 10, it is crucial for the water temperature measuring device 110 to measure the temperature of the cooling water pipes after passing through the heat exchanger 1000. The core objective of the heat exchange process is to reduce the temperature of the heat medium to a suitable range through heat transfer between the cooling water and the heat medium, while the cooling water absorbs heat and its temperature rises. Accurately measuring the temperature of the cooling water after passing through the heat exchanger 1000 can directly reflect the effect of heat exchange. If the measured water temperature is too high, it indicates that the cooling water has not fully absorbed the heat of the heat medium, which may mean that the heat exchange efficiency of the heat exchanger 1000 has decreased. Further inspection of the heat exchanger 1000 is needed to check for problems such as scaling and blockage, so that cleaning or maintenance measures can be taken in time to ensure the heat exchange effect.

[0047] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section. It should be noted that those skilled in the art can make various improvements and modifications to this utility model without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of this utility model.

[0048] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusivity.

[0049] The term "comprises" implies that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprises a..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A conventional island closed-loop cooling water system, characterized in that, The conventional island closed-loop cooling water system includes cooling water piping, a heat exchange space, and a heat exchanger installed within the heat exchange space. The cooling water piping passes through the heat exchanger. The first valve and the second valve are connected, with the inlet end of the first valve connected to the first water source and the inlet end of the second valve connected to the second water source. The outlet ends of both the first valve and the second valve are connected to the inlet of the heat exchange space. The third valve and the fourth valve, the inlet ends of which are both connected to the outlet of the heat exchange space.

2. The conventional island closed-loop cooling water system according to claim 1, characterized in that, The first water source is a natural water body, and the second water source is an artificial water body.

3. The conventional island closed-loop cooling water system according to claim 1, characterized in that, The inlet of the heat exchange space is located at the bottom of the heat exchange space, and the outlet of the heat exchange space is located at the top of the heat exchange space.

4. The conventional island closed-loop cooling water system according to claim 1, characterized in that, It also includes a control valve and a connecting pipeline, one end of the control valve and the inlet end of the second valve are connected through the connecting pipeline, and the other end of the control valve is connected to the second water source.

5. The conventional island closed-loop cooling water system according to claim 4, characterized in that, The connecting pipe is a flexible metal hose.

6. The conventional island closed-loop cooling water system according to claim 4, characterized in that, The control valve is an electrically controlled valve.

7. The conventional island closed-loop cooling water system according to claim 1, characterized in that, The first valve and the fourth valve are electrically operated isolation valves.

8. The conventional island closed-loop cooling water system according to claim 2, characterized in that, The second valve is a steam trap, and the third valve is an air vent valve.

9. The conventional island closed-loop cooling water system according to claim 1, characterized in that, It also includes a differential pressure detection device, wherein the first sampling point of the differential pressure detection device is located between the inlet of the heat exchange space and the junction of the first valve and the second valve; and the second sampling point of the differential pressure detection device is located between the outlet of the heat exchange space and the junction of the third valve and the fourth valve.

10. The conventional island closed-loop cooling water system according to claim 1, characterized in that, It also includes a water temperature measuring device, which is used to measure the temperature of the cooling water pipe after passing through the heat exchanger.

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