Water level unpowered self-balancing system for circulating water tower of thermal power plant and using method thereof

Abstract

The invention discloses a water level unpowered self-balancing system for a circulating water tower of a thermal power plant and a use method of the water level unpowered self-balancing system, and relates to the technical field of water supply of the circulating water tower. The first pipeline extends to the bottom of the first water tower basin; the second pipeline extends to the bottom of the second water tower basin; when the liquid level of the first water tower basin is lower than that of the second water tower basin, condensate water of the second water tower basin flows into the first water tower basin through the first pipeline and the second pipeline. The self-balancing circulating water system not only ensures the continuous and stable operation of the water replenishing pump, but also greatly reduces the operation frequency of the external water replenishing valve of each unit; meanwhile, under the condition that a water supplementing system breaks down or a single unit is shut down for maintenance, rapid adjustment can be achieved, and the stability and reliability of the whole system are ensured.

Description

Technical Field

[0001] The invention relates to the field of circulating water tower water supply, in particular to an unpowered self-balancing system for water level of a circulating water tower in a thermal power plant and a use method thereof. Background Art

[0002] The circulating water tower in a thermal power plant, also known as a cooling tower, is a key equipment used to cool the hot water generated during the power generation process. In a thermal power plant, fuel combustion generates heat energy, which is used to convert water into steam. The steam drives the turbine to rotate and drive the generator to generate electricity. After this process, the steam needs to be condensed back into water for reuse, which is where the circulating water tower comes into play.

[0003] The existing circulating water system uses a main pipe to supply water. Each unit replenishes water into the circulating water tower basin through its own sub-pipe and electric butterfly valve. The water consumption of each unit is different during operation, and the water replenishment valve needs to be operated frequently to maintain the water level. This not only increases the risk of valve seal failure and leakage, but also requires operating personnel to closely monitor and continuously adjust the valve status of different units to ensure the consistency of water levels. This process is complicated and prone to errors. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is that the existing load differences of the units lead to uneven consumption of circulating water, and the valves of each unit need to be adjusted frequently manually to maintain the water level, which is complex and difficult to operate.

[0005] The above technical problem is solved by the following technical solution: The present invention proposes a non-powered self-balancing system for the water level of a circulating water tower in a thermal power plant, which comprises a self-balancing unit, comprising a first pipeline and a second pipeline, wherein the first pipeline is connected to the second pipeline;

[0006] The first pipe extends to the bottom of the first water tower basin, and the second pipe extends to the bottom of the second water tower basin;

[0007] When the liquid level in the first water tower basin is lower than the liquid level in the second water tower basin, condensed water in the second water tower basin flows into the interior of the first water tower basin through the first pipe and the second pipe.

[0008] In a preferred embodiment of the water level unpowered self-balancing system of the circulating water tower of a thermal power plant of the present invention: a first valve is arranged inside the first pipeline toward the first water tower basin, and the first valve controls the opening and closing state of the first pipeline;

[0009] A second valve is arranged inside the second pipeline toward the second water tower basin.

[0010] In a preferred embodiment of the water level unpowered self-balancing system of the circulating water tower of a thermal power plant of the present invention: the water replenishment unit comprises a main pipe and a sub-pipe connected to the main pipe;

[0011] The sub-pipes are in multiple groups, and the first water tower basin and the second water tower basin are connected to the main pipe through the sub-pipes.

[0012] In a preferred embodiment of the water level unpowered self-balancing system of the circulating water tower of a thermal power plant of the present invention: a water supply valve is installed inside the sub-pipe;

[0013] The opening and closing of the water supply valve can control the water supply to the water tower basin.

[0014] In a preferred embodiment of the water level unpowered self-balancing system for circulating water tower in thermal power plant of the present invention: one side of the second pipeline is connected with a diversion pipeline;

[0015] One end of the flow dividing pipeline away from the second pipeline is connected with a third pipeline and a fourth pipeline;

[0016] The third pipe extends to the bottom of the third water tower basin, and the fourth pipe extends to the bottom of the fourth water tower basin.

[0017] In a preferred embodiment of the unpowered self-balancing system for the water level of a circulating water tower in a thermal power plant of the present invention: the first pipeline and the second pipeline are connected to the third pipeline and the fourth pipeline through the diversion pipeline.

[0018] In a preferred embodiment of the water level unpowered self-balancing system of the circulating water tower of a thermal power plant of the present invention: a third valve is arranged inside the third pipeline toward the third water tower basin, and the third valve controls the opening and closing state of the third pipeline;

[0019] A fourth valve is arranged inside the fourth pipeline toward the fourth water tower basin.

[0020] In a preferred embodiment of the unpowered self-balancing system for the water level of a circulating water tower in a thermal power plant of the present invention: the fourth water tower basin and the third water tower basin are connected to the main pipe through the sub-pipe.

[0021] The beneficial effects of the present invention are as follows: the automatic balancing system can not only significantly reduce the problems of poor sealing and leakage caused by frequent operation of the water supply valve, but also accurately control the circulating water level of each unit, reducing the work difficulty of the operating personnel; at the same time, it can stabilize the pressure and flow of the water supply main pipe, avoid the problem of unstable water pump output, and thus extend the service life of the equipment.

[0022] In addition, the technical problem that the present invention needs to solve is that the existing unit load differences lead to uneven consumption of circulating water, and manual frequent adjustment of valves of each machine is required to maintain the water level, which is complex and difficult to operate.

[0023] The above technical problem is solved by the following technical solution: The present invention proposes a method for using a water level unpowered self-balancing system of a circulating water tower in a thermal power plant, which comprises: S1: filling the interior of a pipe of a self-balancing unit with water;

[0024] S2: Supply water to the water tower basins of different units through the water supply pump;

[0025] S3: When the liquid level of the water tower basin of any unit is lower than that of the water tower basins of other units, water is replenished to the low water level water tower basin through the self-balancing unit and the siphon principle.

[0026] The beneficial effects of the present invention are as follows: this method can ensure that the water levels of the water tower basins of all units are automatically kept consistent, without the need to frequently operate the water replenishment valves, thereby greatly reducing operational errors and equipment wear problems caused by manual intervention; secondly, the automatic water replenishment mechanism achieved through the self-balancing unit and the siphon effect can efficiently and stably supply water to the low-water-level water tower basin without relying on additional power, thereby further saving energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments of the present invention are briefly introduced below. Obviously, the drawings described below only relate to some embodiments of the present invention, but are not intended to limit the present invention. Among them:

[0028] Figure 1 The schematic diagram of the structure of the water level unpowered self-balancing system of the circulating water tower of a thermal power plant is shown;

[0029] Figure 2 It shows the schematic diagram of the structure of the self-balancing unit of the water level unpowered self-balancing system of the circulating water tower of a thermal power plant;

[0030] Figure 3 The schematic diagram of the height difference water replenishment operation of the unpowered self-balancing system of the circulating water tower of a thermal power plant is shown. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below in conjunction with specific implementation methods and drawings.

[0032] The terms used in the present invention are those general terms currently widely used in the art in consideration of the functions of the present invention, but these terms may vary according to the intention of a person of ordinary skill in the art, precedents, or new technologies in the art. In addition, specific terms may be selected by the applicant, and in this case, their detailed meanings will be described in the detailed description of the present invention. Therefore, the terms used in the specification should not be understood as simple names, but rather as a general description based on the meaning of the terms and the present invention.

[0033] Reference Figures 1 to 3 The present embodiment provides a non-powered self-balancing system for the water level of a circulating water tower in a thermal power plant, including a self-balancing unit 1, including a first pipe 11, and a second pipe 12 connected to the first pipe 11; the first pipe 11 extends to the bottom of the first water tower basin M1, and the second pipe 12 extends to the bottom of the second water tower basin M2.

[0034] Specifically, the bottom of the first pipe 11 is submerged below the liquid level of the first water tower basin M1, and the bottom of the second pipe 12 is also submerged below the liquid level of the second water tower basin M2; thereby ensuring that no air enters the first pipe 11 and the second pipe 12, thereby ensuring a more balanced and stable transportation of condensed water.

[0035] It should be noted that when the liquid level in the first water tower basin M1 is lower than the liquid level in the second water tower basin M2, a vacuum pump is used to discharge the air inside the first pipe 11 and the second pipe 12, and then under the action of atmospheric pressure, the water inside the water tower basin completely enters the first pipe 11 and the second pipe 12.

[0036] In this state, the pressures inside the second water tower basin M2, the first water tower basin M1, the first pipe 11 and the second pipe 12 are in equilibrium; however, the liquid level in the second water tower basin M2 is higher than that in the first water tower basin M1; the water in the second water tower basin M2 flows to the first water tower basin M1 due to gravity, and according to the siphon principle, the water flow will form a continuous flow in the connecting pipe, flowing from the high liquid level to the low liquid level, that is, from the second water tower basin M2 to the first water tower basin M1.

[0037] As water flows from the second water tower basin M2 to the first water tower basin M1, the liquid level in the second water tower basin M2 gradually decreases, and the liquid level in the first water tower basin M1 rises until the two reach the same level, at which time the siphon stops naturally; in this process, no additional power source is required, and it relies entirely on gravity and the siphon effect.

[0038] As an optional embodiment, a first valve 111 is arranged inside the first pipe 11 toward the first water basin M1, and the first valve 111 controls the opening and closing state of the first pipe 11; a second valve 121 is arranged inside the second pipe 12 toward the second water basin M2.

[0039] It should be noted that the first pipe 11 extends in the direction of the first water tower basin M1, and a first valve 111 is installed inside the first pipe 11; and the first valve 111 is an electric butterfly valve, and the opening and closing of the first valve 111 can be controlled by a remote controller.

[0040] The main function of the first valve 111 is to ensure that the pipeline inside the first pipeline 11 is in a closed or open state. When the unit corresponding to the first pipeline 11 needs to be repaired and is temporarily not in use, there is no need to add water to the first water tower basin M1. The first valve 111 can be closed to prevent water from flowing into the first water tower basin M1; so as to ensure that the staff can perform maintenance and repair on the shut down unit.

[0041] The second valve 121 is similar to the first valve 111 and will not be described in detail here; the main function of the second valve 121 is to control the opening and closing state of the second pipe 12, so as to be applicable to a variety of usage conditions, making the device more flexible during use.

[0042] In one embodiment provided in the present application, a water replenishment unit 2 is included, including a main pipe 21 and a sub-pipe 22 connected to the main pipe 21; the sub-pipes 22 are in multiple groups, and the first water tower basin M1 and the second water tower basin M2 are connected to the main pipe 21 through the sub-pipes 22.

[0043] It should be noted that the main pipe 21 is arranged parallel to the bottom surface, and a water supply pump is installed at the end of the main pipe 21; the water inside the reservoir can be transported to the inside of the main pipe 21 through the water supply pump; the water inside the main pipe 21 can flow to the first water tower basin M1 or the second water tower basin M2 through the sub-pipe 22 connected thereto.

[0044] When the water tower basin needs to be replenished with water, the water replenishment pump is started to pump condensed water into the main pipe 21, and then the water flows into the water tower basin along the sub-pipe 22 for use by the unit during operation.

[0045] As an optional embodiment, a water supply valve 221 is installed inside the sub-pipe 22; the opening and closing of the water supply valve 221 can control the water supply to the water tower basin.

[0046] It should be noted that under normal conditions, the main pipe 21 and the sub-pipe 22 are in a connected state, and the water flowing into the main pipe 21 can flow into the water tower along the sub-pipe 22 .

[0047] Specifically, during the actual operation of the unit, one of the units needs to be regularly inspected and maintained. However, in order to ensure that other units can work normally, it is necessary to ensure that there is no water in the water tower basin of the inspection unit, and then the operating unit can work normally. Therefore, it is necessary to close the passage inside the sub-pipe 22 through the water supply valve 221, so that the water tower basin is free of water, so that the staff can inspect and maintain the unit.

[0048] In some embodiments, one side of the second pipe 12 is connected to a diversion pipe 13; a fifth valve 131 is installed inside the diversion pipe 13; one end of the diversion pipe 13 away from the second pipe 12 is connected to a third pipe 14 and a fourth pipe 15; the third pipe 14 extends to the bottom of the third water tower basin M3, and the fourth pipe 15 extends to the bottom of the fourth water tower basin M4.

[0049] It should be noted that the shunt pipe 13 is connected to the second pipe 12, and the shunt pipe 13 mainly serves to connect other units, so that a plurality of units greater than two can be connected, thereby ensuring that the entire balancing system can be more stable and efficient.

[0050] The shunt pipe 13 is a three-way structure, a fifth valve 131 is installed inside the vertical section of the shunt pipe 13, and an air pump is installed at the end of the vertical section of the shunt pipe 13; starting the air pump can discharge the inside of the shunt pipe 13 and the residual air, so that the inside of the self-balancing unit pipe can be filled with condensed water, so that the connecting pipe can realize the siphon principle, and the high liquid level water can be transported to the low liquid level.

[0051] When the pipeline is filled with water and in a balanced state, the fifth valve 131 will be closed. At this time, the pipeline of the self-balancing system is in a balanced state. Due to the height difference between the liquid levels in the water tower basins, the high liquid level flows to the low liquid level.

[0052] The third pipe 14 and the fourth pipe 15 correspond to the water tower basins of other units respectively; and the third pipe 14 is connected to the shunt pipe 13, and an internally connected pipe is formed by the fourth pipe 15, the third pipe 14, the shunt pipe 13, the second pipe 12 and the first pipe 11, thereby achieving the purpose of replenishing water from a high liquid level water tower basin to a low liquid level water tower basin.

[0053] In some embodiments, a third valve 141 is disposed inside the third pipe 14 toward the third water basin M3, and the third valve 141 controls the opening and closing state of the third pipe 14; a fourth valve 151 is disposed inside the fourth pipe 15 toward the fourth water basin M4.

[0054] It should be noted that the third pipeline 14 is arranged inside the third valve 141, and the connectivity and closure of the third pipeline 14 can be ensured by opening and closing the third valve 141; when the third valve 141 is in an open state, when the liquid level of the water tower basin connected to the bottom of the third pipeline 14 is low, the liquid inside the high liquid level water tower basin can be transported to the inside of the water tower basin arranged at the bottom of the third pipeline 14 through the pipeline of the self-balancing system.

[0055] In some embodiments, the fourth water tower basin M4 and the third water tower basin M3 are connected to the main pipe 21 through the sub-pipe 22 .

[0056] It should be noted that the fourth water tower basin M4 and the third water tower basin M3 are also replenished with water through the sub-pipe 22. When water replenishment is needed, the water replenishment pump connected to the end of the main pipe 21 can quickly transport water to the inside of the water tower basin.

[0057] The deepest part of the forepool of the water tower basin of all units is connected with a connecting pipe, and a filter is installed at the end of the connecting pipe of each unit to prevent clogging by debris; before the first start of this system, the first valve, the second valve, the third valve and the fourth valve are opened, and the fifth valve is closed; then after the vacuum pump is started, the fifth valve is opened to pump air so that the inside of the pipeline is filled with water, and then the fifth valve, the third valve, the second valve, the fourth valve and the first valve are closed in sequence, and the connecting pipe is now completely filled with water; when all four units are running, the first valve, the second valve, the third valve and the fourth valve are all opened, and the water replenishment valve of any unit can be opened at this time. When the water level of any unit is lower than that of the other three units, the communicating device and the siphon principle work, and the water in the forepool with a high water level naturally replenishes water to the forepool of the unit with a low water level, and the water level of the four units is always kept consistent.

[0058] When one of the units is shut down for maintenance, such as unit #2, the second water tower basin needs to be drained. At this time, the second valve is closed, and the other units replenish water to maintain the water level. The system's external water replenishment can be switched to any of the other three units for replenishment, and the water replenishment for unit #2 is stopped; when the maintenance of unit #2 is completed and the water level is restored, the external water replenishment door of unit #2 is opened to replenish the water level to the normal level at one time, and the 2 valves are opened to resume normal operation.

[0059] Reference Figure 3 ,This embodiment provides a method for using a water level unpowered self-balancing system of a circulating water tower in a thermal power plant, including, S1: filling the interior of a pipe of a self-balancing unit with water;

[0060] Initial startup preparation: To ensure that the pipes of the self-balancing unit are completely filled with water during the initial startup, the following are detailed steps:

[0061] Open the valves at the ends of all connecting pipes: open the first valve, the second valve, the third valve and the fourth valve in sequence. Make sure these valves are fully open so that the connecting pipes between the circulating water forebays of each unit can flow freely.

[0062] Keep the fifth valve closed to prevent outside air from entering the system.

[0063] Correctly connect the vacuum pump to the dedicated vacuum port of the connecting pipe; ensure that the connection is tight and leak-free to avoid air infiltration during the vacuum process.

[0064] Start the vacuum pump and open the fifth valve to start extracting air from the connecting pipe. At this time, the vacuum pump will extract the air in the pipeline through the fifth valve, gradually forming a negative pressure environment, prompting water to flow into the connecting pipe.

[0065] Pay close attention to the working status and discharge of the vacuum pump; when the vacuum pump begins to discharge a continuous flow of water instead of air, it indicates that the air in the connecting pipe has been basically exhausted and the pipe is being filled with water.

[0066] Close the valves gradually in the following order:

[0067] Close the fifth valve: Once it is confirmed that the vacuum pump is discharging a continuous flow of water, immediately close the fifth valve and stop the vacuum pump to prevent excessive water from flowing into the vacuum pump and causing damage.

[0068] Close the third valve: Next, close the third valve to further restrict the water flow in and out of the path, helping to stabilize the water level in the system.

[0069] Close the second valve: Then close the second valve to continue to narrow the water flow channel to ensure that the water level in the pipe rises.

[0070] Close the first valve: Close the first valve immediately to further control the direction of water flow and ensure that all connecting pipes are filled with water.

[0071] Finally, close the fourth valve: Finally, close the fourth valve to complete the closure of the entire system, ensuring that the connecting pipe is completely filled with water and no air remains.

[0072] S2: Water is supplied to the water tower basins of different units through a water supply pump.

[0073] In order to ensure that the four units can have a stable water supply under normal operation and that the water level in the forebay of the circulating water of each unit is always consistent:

[0074] First, open the valves at the ends of all the connecting pipes: make sure that the first valve, the second valve, the third valve and the fourth valve are all in the fully open state; this will allow the connecting pipes between the units to flow freely, forming an interconnected water level balance system.

[0075] Start and manage the make-up water pump, and select any unit as the main make-up water source based on actual needs or convenience; for example, assume that unit #1 is selected as the main water supply unit.

[0076] It is only necessary to open the water supply valve of the selected unit, such as unit #1; at this time, the water supply pump will provide supplementary water to the entire system through the water supply pipeline of the unit.

[0077] Automatic water level balance is achieved by using the communicating vessel and siphon principle. Due to the communicating vessel principle, when the liquid level in the water tower basin of a unit is lower than that of other units, the water in the forepool with high water level will naturally flow to the forepool with low water level until the water levels of all units reach the same level.

[0078] The siphon effect further enhances this process, allowing water to flow from high water levels to low water levels even without additional power, ensuring that the water level is always balanced.

[0079] Use an automated monitoring system or regularly manually check the water level in the water tower basin of each unit to ensure that the water level remains within the set range; if the water level of a unit is found to be abnormally low or high, the cause should be investigated in a timely manner and appropriate measures should be taken.

[0080] If the water supply pump fails, the water supply can be switched to the water supply system of other units to continue to provide water for the entire system, ensuring the continuous and stable operation of the system.

[0081] When a unit needs to be shut down for maintenance, the relevant valves are closed according to specific operating procedures to stop the water supply to the unit, while ensuring that the water level balance between other units is not affected.

[0082] S3: When the liquid level of the water tower basin of any unit is lower than that of the water tower basins of other units, water is replenished to the low water level water tower basin through the self-balancing unit and the siphon principle.

[0083] To ensure that when the water tower basin liquid level of a unit is lower than that of other units, the system can automatically and efficiently guide the high water level water into the low water level forebay and maintain the water level balance among other units.

[0084] Furthermore, high-precision intelligent water level sensors are installed in the water tower basin of each unit to monitor the water level changes of each unit in real time; these sensors can accurately sense tiny water level differences and transmit data to the central control system.

[0085] A minimum water level threshold is set for each unit; once the water level of a unit drops below the threshold, the system will automatically start the water replenishment mechanism without manual intervention.

[0086] Since the circulating water forebays of all units are connected through connecting pipes, a large connecting system is formed; according to the connecting vessel principle, when the water level of one unit is low, other units with higher water levels will naturally supply water to it until the water levels of all units reach the same level.

[0087] The siphon effect further enhances this process, allowing water to flow more smoothly from high to low water levels. Even without additional power, water continues to flow, ensuring that water levels are quickly equalized.

[0088] Specifically, a one-way valve is installed at the inlet of the connecting pipe of each unit, which only allows water to flow from high water level to low water level to prevent backflow. This not only protects the safe operation of each unit, but also avoids over-supply problems caused by water flow fluctuations.

[0089] An adjustable flow control device is provided in the connecting pipe to adapt to the water replenishment demand under different working conditions; for example, when the water level difference is large, the flow rate can be appropriately increased to speed up the water replenishment; and when the water level is close to equilibrium, the flow rate is reduced to prevent excessive water replenishment.

[0090] In summary, the self-balancing circulating water system not only ensures the continuous and stable operation of the water supply pump, but also greatly reduces the operation frequency of the external water supply valves of each unit; at the same time, in the event of a water supply system failure or a single unit shutdown for maintenance, it can be quickly adjusted to ensure the stability and reliability of the entire system.

[0091] It is important to note that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A water level unpowered self-balancing system for a circulating water tower in a thermal power plant, characterized by: include, A self-balancing unit (1) comprises a first pipeline (11) and a second pipeline (12), wherein the first pipeline (11) and the second pipeline (12) are connected to each other; The first pipe (11) extends to the bottom of the first water tower basin (M1), and the second pipe (12) extends to the bottom of the second water tower basin (M2); When the liquid level of the first water tower basin (M1) is lower than the liquid level of the second water tower basin (M2), condensed water in the second water tower basin (M2) flows into the interior of the first water tower basin (M1) through the first pipe (11) and the second pipe (12).

2. The unpowered self-balancing system for water level in a circulating water tower of a thermal power plant according to claim 1 is characterized in that: A first valve (111) is provided inside the first pipeline (11) in the direction of the first water tower basin (M1), and the first valve (111) controls the opening and closing state of the first pipeline (11); A second valve (121) is provided inside the second pipeline (12) in the direction of the second water tower basin (M2).

3. The unpowered self-balancing system for water level in a circulating water tower of a thermal power plant according to claim 1 or 2, characterized in that: Also includes, A water replenishment unit (2), comprising a main pipe (21) and a sub-pipe (22) connected to the main pipe (21); The sub-pipes (22) are provided in a plurality of groups, and the first water tower basin (M1) and the second water tower basin (M2) are connected to the main pipe (21) via the sub-pipes (22).

4. The unpowered self-balancing system for water level in a circulating water tower of a thermal power plant according to claim 3 is characterized in that: A water supply valve (221) is installed inside the sub-pipe (22); The water supply valve (221) can be opened and closed to control the water supply to the water tower basin.

5. The unpowered self-balancing system for water level in a circulating water tower of a thermal power plant according to claim 4 is characterized in that: One side of the second pipeline (12) is connected to a diversion pipeline (13); A fifth valve (131) is installed inside the diversion pipeline (13); One end of the diversion pipeline (13) away from the second pipeline (12) is connected to a third pipeline (14) and a fourth pipeline (15); The third pipe (14) extends to the bottom of the third water tower basin (M3), and the fourth pipe (15) extends to the bottom of the fourth water tower basin (M4).

6. The unpowered self-balancing system for water level in a circulating water tower of a thermal power plant according to claim 5 is characterized in that: The first pipeline (11) and the second pipeline (12) are connected to the third pipeline (14) and the fourth pipeline (15) via the diversion pipeline (13).

7. The unpowered self-balancing system for water level in a circulating water tower of a thermal power plant according to claim 5 or 6, characterized in that: A third valve (141) is provided inside the third pipeline (14) in the direction of the third water tower basin (M3), and the third valve (141) controls the opening and closing state of the third pipeline (14); A fourth valve (151) is provided inside the fourth pipeline (15) toward the fourth water tower basin (M4).

8. The unpowered self-balancing system for water level in a circulating water tower of a thermal power plant according to claim 5 is characterized by: The fourth water tower basin (M4) and the third water tower basin (M3) are connected to the main pipe (21) through the sub-pipe (22).

9. A method for using a water level unpowered self-balancing system for a circulating water tower in a thermal power plant, characterized in that: include, S1: Fill the pipe of the self-balancing unit with water; S2: Supply water to the water tower basins of different units through the water supply pump; S3: When the liquid level of the water tower basin of any unit is lower than that of the water tower basins of other units, water is replenished to the low water level water tower basin through the self-balancing unit and the siphon principle.

Images