Dispersely-arranged adjustable heat dissipation type water seal

Abstract

The utility model belongs to the technical field of multi-stage water seal systems, and particularly relates to a dispersedly-arranged adjustable heat dissipation type water seal which comprises a shaft seal heater, a main pipeline, a fixed water seal assembly, an adjustable water seal assembly, a condenser and a DCS. A shaft seal heater, a shaft heater drain outlet valve, a fixed water seal assembly, an adjustable water seal inlet manual valve, an adjustable water seal assembly, an adjustable water seal outlet manual valve and a condenser are sequentially connected to a pipeline of the main pipeline. The fixed water seal assembly comprises a fixed first-stage water seal, a fixed second-stage water seal, a fixed third-stage water seal and a fixed fourth-stage water seal which are sequentially arranged on the main pipeline, and the adjustable water seal assembly is arranged, so that the height of the water seal can be effectively adjusted quickly, accurately and reliably according to the vacuum change of a unit during operation; the problem that vacuum of a unit is affected by air leakage of the water seal in operation is solved, vacuum of the condenser is effectively improved, coal consumption of the unit is reduced, and the device has important significance for safe and economical operation of the unit.

Description

Technical Field

[0001] This utility model relates to the field of multi-stage water seal systems, specifically a distributed adjustable heat dissipation water seal. Background Technology

[0002] The multi-stage water seal system utilizes a tiered overflow method for condensate drainage. Steam, air, and non-condensable gases within the shaft seal heater are trapped by the water column within the multi-stage water seal, preventing leakage into the condenser. The height of the water column depends on the pressure difference between the pressure inside the shaft seal heater and the condenser vacuum. The multi-stage water seal structure from the shaft seal heater to the condenser is designed to increase the resistance of the condensate drainage and isolate the air from the shaft seal heater. Theoretically, the condensate from the shaft seal heater passes through the multi-stage water seal and then returns to the steam side of the condenser at a certain height. The flow resistance plus the height difference equals the condenser vacuum, which is the most normal operating condition. Excessive water level in the shaft seal heater may overload the shaft seal fan, potentially causing motor burnout and cold-induced jamming of the turbine shaft seal. During normal operation, the condensate from the shaft seal heater forms a small water seal at the condensate outlet, maintaining visibility of the water level and allowing operators to assess the proper functioning of the multi-stage water seal system. If the water level is lower than the drain outlet, the height of the multi-stage water seal column will be insufficient, and the vacuum inside the condenser will be around -90 kPa. This will directly draw the steam-gas mixture in the shaft seal heater into the condenser, causing the vacuum of the condenser to deteriorate.

[0003] In existing power plants, most multi-stage water seal structures are fixed 10-meter water column structures. During operation, due to the rise in water temperature and changes in steam-water density, the 10-meter water seal cannot meet the 10-meter water column requirement, and the water column height cannot be adjusted. As a result, the multi-stage water seal cannot achieve air isolation and maintain the water-draining function, which affects the vacuum level of the unit's condenser and the optimal heat exchange performance of the shaft. Furthermore, it is difficult to perform online maintenance when the water seal fails. Utility Model Content

[0004] The purpose of this invention is to provide a distributed adjustable heat dissipation water seal to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a distributed adjustable heat dissipation water seal, comprising a shaft seal heater, a main pipeline, a fixed water seal assembly, an adjustable water seal assembly, a condenser, and a DCS system. The main pipeline is sequentially connected to a shaft seal heater, a shaft seal drain outlet valve, a fixed water seal assembly, an adjustable water seal inlet manual valve, an adjustable water seal assembly, an adjustable water seal outlet manual valve, and a condenser. The DCS system is electrically connected to the condenser and the adjustable water seal assembly. The fixed water seal assembly includes fixed... The system includes a primary water seal, a fixed secondary water seal, a fixed tertiary water seal, and a fixed quaternary water seal. The main pipeline is connected to a bypass pipeline. The connection points at both ends of the bypass pipeline are located on the main pipeline between the fixed secondary and fixed tertiary water seals, and on the main pipeline between the adjustable water seal outlet manual valve and the condenser, respectively. The bypass pipeline is connected to the main pipeline between the fixed quaternary water seal and the adjustable water seal inlet manual valve. A bypass manual valve and a bypass U-shaped water seal are installed at the connection point between the main pipeline between the fixed quaternary water seal and the adjustable water seal inlet manual valve and the bypass pipeline.

[0006] Preferably, the shaft seal heater is connected to a liquid level measuring tube, an electronic water level gauge is installed in the liquid level measuring tube, and an emergency drain electric valve is bolted to one end of the bypass pipe near the fixed secondary water seal. The DCS system is electrically connected to the electronic water level gauge and the emergency drain electric valve.

[0007] Preferably, the upper ends of the fixed primary water seal, fixed secondary water seal, fixed tertiary water seal, and fixed quaternary water seal are all equipped with water seal air release valves.

[0008] Preferably, the fixed primary water seal is connected to a water seal replenishment valve.

[0009] Preferably, cooling sleeves are installed on the outer sides of the fixed primary water seal, fixed secondary water seal, fixed tertiary water seal and fixed quaternary water seal. The cooling sleeves of the fixed primary water seal, fixed secondary water seal, fixed tertiary water seal and fixed quaternary water seal are connected in sequence. A water seal cooling inlet valve is provided above the cooling sleeve on the fixed primary water seal and a water seal cooling outlet valve is provided above the cooling sleeve on the fixed quaternary water seal.

[0010] Preferably, the lower end of the cooling jacket on the fixed primary water seal is connected to a water seal drain valve.

[0011] Preferably, the adjustable water seal assembly includes an adjustable water seal assembly shell, an upper seal, a guide ring, a tension rod, a lower seal, and an actuator. The tension rod is installed in the adjustable water seal assembly shell, and a guide ring is provided on the outer side of the tension rod. The guide ring is slidably connected to the inner cavity of the adjustable water seal assembly shell. The upper seal and the lower seal are respectively installed between the upper and lower sides of the tension rod and the inner cavity of the adjustable water seal assembly shell. The bottom of the adjustable water seal assembly shell is connected by bolts to an actuator that drives the tension rod to move up and down.

[0012] Preferably, the adjustable water seal assembly has a base bolted to its outer shell.

[0013] Preferably, a main U-shaped water seal is installed on the main pipeline of the shaft seal heater.

[0014] Compared with the prior art, the beneficial effects of this utility model are:

[0015] 1) By introducing cooling water into the cooling jacket, the flowing medium inside the fixed water seal assembly is effectively cooled, preventing changes in the density of the medium due to vaporization. This ensures the effective height of the designed water seal, improves the stability and economy of the system operation, and solves the problem of water seal effect caused by vaporization of the water seal medium.

[0016] 2) By setting an adjustable water seal component, the water seal height can be quickly, accurately and reliably adjusted according to the changes in unit vacuum during operation, solving the problem of water seal leakage affecting unit vacuum during operation, effectively improving condenser vacuum, reducing unit coal consumption, and is of great significance to the safe and economical operation of the unit.

[0017] 3) An emergency drain electric valve was designed. In case of internal leakage in the shaft heater or uncontrollable rise in the shaft heater water level, the emergency drain electric valve can be used in conjunction with the bypass pipe to effectively drain water, which improves the safety of unit operation, prevents water from entering the turbine shaft seal due to full water in the shaft heater, endangers the safe operation of the turbine, and avoids water damage to the shaft seal fan of the shaft heater.

[0018] 4) By adding a bypass manual valve, a bypass U-shaped water seal, an adjustable water seal inlet manual valve, and an adjustable water seal outlet manual valve to the bypass pipe and adjustable water seal assembly, the system can effectively isolate the system in case of an adjustable water seal failure, thus meeting the requirements for online maintenance of the adjustable water seal. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of this utility model.

[0020] In the diagram: 1. Water seal water supply valve; 2. Shaft seal heater; 3. Electronic water level gauge; 4. Liquid level measuring tube; 5. Main U-shaped water seal; 6. Shaft seal drain outlet valve; 7. Fixed primary water seal; 8. Fixed secondary water seal; 9. Fixed tertiary water seal; 10. Fixed quaternary water seal; 11. Bypass pipe; 12. Water seal air vent valve; 13. Emergency drain electric valve; 14. Water seal cooling inlet valve; 15. Water seal cooling outlet. 16. Bypass U-shaped water seal; 17. Adjustable water seal inlet manual valve; 18. Adjustable water seal outlet manual valve; 19. Condenser; 20. Water seal drain valve; 21. Water seal base plate; 22. Tension rod; 23. Lower seal; 24. Actuator; 25. Base; 26. Adjustable water seal assembly housing; 27. Main pipe; 28. Cooling jacket; 29. ​​Bypass manual valve; 30. Guide ring; 31. Upper seal. Detailed Implementation

[0021] 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, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model 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 utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0024] Example:

[0025] Please see Figure 1This utility model provides a technical solution: a distributed adjustable heat dissipation water seal, including a shaft seal heater 2, a main pipeline 27, a fixed water seal assembly, an adjustable water seal assembly, a condenser 19, and a DCS system. The DCS system is an existing system in the power plant. The main pipeline 27 is sequentially connected to the shaft seal heater 2, a shaft seal drain outlet valve 6, a fixed water seal assembly, an adjustable water seal inlet manual valve 17, an adjustable water seal assembly, an adjustable water seal outlet manual valve 18, and the condenser 19. The DCS system is electrically connected to the condenser 19 and the adjustable water seal assembly. The condenser 19 is connected to a vacuum pressure transmitter. The fixed water seal assembly includes components sequentially arranged on the main pipeline 27. The system includes a fixed primary water seal 7, a fixed secondary water seal 8, a fixed tertiary water seal 9, and a fixed quaternary water seal 10. The main pipeline 27 is connected to a bypass pipeline 11. The connection points at both ends of the bypass pipeline 11 are located on the main pipeline 27 between the fixed secondary water seal 8 and the fixed tertiary water seal 9, and on the main pipeline 27 between the adjustable water seal outlet manual valve 18 and the condenser 19, respectively. The bypass pipeline 11 is connected to the main pipeline 27 between the fixed quaternary water seal 10 and the adjustable water seal inlet manual valve 17. A bypass manual valve 29 and a bypass U-shaped water seal 16 are installed at the connection point between the main pipeline 27 between the fixed quaternary water seal 10 and the adjustable water seal inlet manual valve 17 and the bypass pipeline 11.

[0026] The shaft seal heater 2 is connected to the liquid level measuring tube 4, and the liquid level measuring tube 4 is equipped with an electronic water level gauge 3. The bypass pipe 11 is connected to the emergency drain electric valve 13 by bolts at one end near the fixed secondary water seal 8. The DCS system is electrically connected to the electronic water level gauge 3 and the emergency drain electric valve 13.

[0027] The upper ends of the fixed primary water seal 7, fixed secondary water seal 8, fixed tertiary water seal 9 and fixed quaternary water seal 10 are all equipped with water seal air release valves 12, which correspond to the primary water seal air release valve, secondary water seal air release valve, tertiary water seal air release valve and quaternary water seal air release valve respectively.

[0028] The fixed primary water seal 7 is connected to the water seal replenishment valve 1.

[0029] Cooling jackets 28 are installed on the outer sides of the fixed primary water seal 7, fixed secondary water seal 8, fixed tertiary water seal 9, and fixed quaternary water seal 10. The cooling jackets 28 of the fixed primary water seal 7, fixed secondary water seal 8, fixed tertiary water seal 9, and fixed quaternary water seal 10 are connected sequentially. A water seal cooling inlet valve 14 is installed above the cooling jacket 28 on the fixed primary water seal 7, and a water seal cooling outlet valve 15 is installed above the cooling jacket 28 on the fixed quaternary water seal 10. Before the system is put into operation, the water seal cooling inlet valve 14 and the water seal cooling outlet valve 15 can be opened. During operation, the valve opening can be adjusted according to the temperature of the medium inside the water seal to effectively reduce the temperature of the medium inside the water seal and prevent its vaporization.

[0030] A water seal drain valve 20 is connected to the lower end of the cooling jacket 28 on the fixed primary water seal 7.

[0031] The adjustable water seal assembly includes an adjustable water seal housing 26, an upper seal 31, a guide ring 30, a tension rod 22, a lower seal 23, and an actuator 24. The tension rod 22 is installed in the adjustable water seal housing 26. A guide ring 30 is provided on the outside of the tension rod 22. The guide ring 30 is slidably connected to the inner cavity of the adjustable water seal housing 26. The upper seal 31 and the lower seal 23 are respectively installed between the upper and lower sides of the tension rod 22 and the inner cavity of the adjustable water seal housing 26. The bottom of the adjustable water seal housing 26 is bolted to an actuator 24 that drives the tension rod 22 to move up and down. The actuator 24 only needs to be able to achieve the function of driving the tension rod 22 to move, such as an electric push rod.

[0032] The adjustable water seal assembly housing 26 is bolted to a base 25.

[0033] The bottoms of the base 25 and the cooling jacket 28 are both mounted on the water seal base plate 21.

[0034] A main U-shaped water seal 5 is installed on the main pipeline 27 of the shaft seal heater 2.

[0035] This solution eliminates the possibility of multi-stage water seal vacuum leakage, improves operational economy, reduces vacuum pump power consumption, and effectively maintains condenser vacuum. Due to its ability to maintain the effectiveness and timeliness of the water seal height, the condenser vacuum is increased by an average of over 0.5 kPa under the same conditions, resulting in an average coal saving of 1.0 g / kWh. Assuming 4000 hours of unit operation, a 600MW unit can save 6000 tons of standard coal annually. At 800 yuan per ton of standard coal, this translates to an annual saving of 1.68 million yuan, achieving significant energy savings. After implementation, the solution improves the heat exchange performance of the shaft heater and facilitates smoother drainage, which is of great significance for the safe and economical operation of the unit.

[0036] Working principle: The operation process of this device is as follows: Before operation, confirm that the actuator 24 in the adjustable water seal assembly is powered on and that the vacuum pressure transmitter on the condenser 19 is normal. Then, use the water seal water supply valve 1 to inject water and purge air from the water seal. Then, open the water seal cooling inlet valve 14 and the water seal cooling outlet valve 15. When the unit vacuum reaches -86Kpa (the vacuum value before the turbine starts), the adjustable water seal assembly will participate in the water seal height adjustment. For every 0.1Kpa increase in the unit vacuum, the adjustable water seal will move downward by 100mm (controlled by the actuator 24). The water seal height is adjusted at any time according to the changes in the unit vacuum to be slightly greater than the air isolation requirement, while ensuring smooth drainage. In addition, the principle of distributed water seal arrangement is also utilized. The main U-shaped water seal 5 is arranged according to the shaft water level requirement, so that the shaft water level is effectively controlled to ensure the heat exchange effect.

[0037] The vacuum pressure transmitter performs measurement and outputs signals. At the same time, the actuator 24 in the adjustable water seal assembly remains in the 0 position and does not operate. When the vacuum of the condenser 19 reaches -86 kPa, the signal is sent to the DCS system. The DCS system outputs a control signal to the actuator 24, which uses cooling water to effectively cool the medium in the water seal and maintain a constant density. The height of the water seal column of the adjustable water seal assembly is accurately controlled according to the vacuum of the condenser 19 to ensure the effective water seal height and prevent air from leaking into the condenser 19, which would increase the power consumption of the vacuum pump and affect the unit vacuum.

[0038] In the event of a failure of the adjustable water seal component, a bypass pipe 11 is added to ensure that online maintenance can be carried out under the condition that the adjustable water seal component is abnormal and without affecting the normal operation of the unit. When the adjustable water seal component is abnormal, the operator opens the bypass manual valve 29 on the spot, and then closes the adjustable water seal inlet manual valve 17 and the adjustable water seal outlet manual valve 18, and the bypass system is put into operation.

[0039] Main working drainage loop:

[0040] Drainage process: Main U-shaped water seal 5 → Shaft drain outlet valve 6 → Fixed primary water seal 7 → Fixed secondary water seal 8 → Fixed tertiary water seal 9 → Fixed quaternary water seal 10 → Adjustable water seal inlet manual valve 17 → Adjustable water seal assembly → Adjustable water seal outlet manual valve 18 → Condenser 19. (Emergency drain electric valve 13 is closed, bypass manual valve 29 is closed).

[0041] Control logic: The vacuum type pressure transmitter of condenser 19 measures the unit vacuum online → outputs the measurement signal to the DCS system → the power plant DCS system converts, calculates and compares the signal → when the unit vacuum is -86Kpa (vacuum value before turbine startup) → the DCS system outputs the execution command → the actuator 24 of the adjustable water seal assembly receives the command → the water seal height is adjusted, and the water seal is adjusted downward by 100mm for every 0.1Kpa increase in unit vacuum. The water seal height is adjusted to be slightly greater than the air isolation requirement according to the changes in unit vacuum, while ensuring smooth drainage.

[0042] Emergency drainage circuit:

[0043] Emergency drainage process: Main U-shaped water seal 5 → Shaft drainage outlet valve 6 → Fixed primary water seal 7 → Fixed secondary water seal 8 → Emergency drainage electric valve 13 → Bypass pipe 11 → Condenser 19.

[0044] Control logic: Electronic water level gauge 3 measures water level → outputs measurement signal to DCS system → power plant DCS system converts, calculates and compares → when the shaft water level reaches a certain alarm value → DCS system outputs execution command → emergency drain electric valve 13 receives command → emergency drain electric valve 13 opens for emergency water release.

[0045] bypass:

[0046] Bypass drainage process: Main U-shaped water seal 5 → Shaft drain outlet valve 6 → Fixed primary water seal 7 → Fixed secondary water seal 8 → Fixed tertiary water seal 9 → Fixed quaternary water seal 10 → Bypass manual valve 29 → Bypass pipe 11 → Condenser 19. (Adjustable water seal inlet manual valve 17 and adjustable water seal outlet manual valve 18 are closed).

[0047] Control logic: When the adjustable water seal malfunctions → manually open the bypass manual valve 29 → manually close the adjustable water seal inlet manual valve 17 → manually close the adjustable water seal outlet manual valve 18.

[0048] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. It is obvious to those skilled in the art that this utility model is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or basic characteristics of this utility model. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this utility model is defined by the appended claims rather than the foregoing description. Therefore, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this utility model, and no reference numerals in the claims should be considered as limiting the scope of the claims.

[0049] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A distributed adjustable heat dissipation water seal, comprising a shaft seal heater (2), a main line pipe (27), a fixed water seal assembly, an adjustable water seal assembly, a condenser (19) and a DCS system, characterized in that: The main pipe (27) is connected in sequence to a shaft seal heater (2), a shaft drain outlet valve (6), a fixed water seal assembly, an adjustable water seal inlet manual valve (17), an adjustable water seal assembly, an adjustable water seal outlet manual valve (18) and a condenser (19); the DCS system is electrically connected to the condenser (19) and the adjustable water seal assembly; the fixed water seal assembly comprises a fixed primary water seal (7), a fixed secondary water seal (8), a fixed tertiary water seal (9) and a fixed quaternary water seal (10) which are arranged in sequence on the main pipe (27); the main pipe (27) is connected to a bypass pipe (11); the bypass pipe The connection points at both ends of (11) are respectively located on the main pipeline (27) between the fixed secondary water seal (8) and the fixed tertiary water seal (9) and the main pipeline (27) between the adjustable water seal outlet manual valve (18) and the condenser (19), and the bypass pipeline (11) is connected to the main pipeline (27) between the fixed tertiary water seal (10) and the adjustable water seal inlet manual valve (17). A bypass manual valve (29) and a bypass U-shaped water seal (16) are installed at the connection point between the main pipeline (27) between the fixed tertiary water seal (10) and the adjustable water seal inlet manual valve (17) and the bypass pipeline (11).

2. The dispersedly arranged adjustable heat dissipation water seal according to claim 1, characterized in that: The shaft seal heater (2) is connected to a liquid level measuring tube (4), an electronic water level gauge (3) is installed in the liquid level measuring tube (4), one end of the bypass tube (11) close to the fixed secondary water seal (8) is connected to an emergency drain electric valve (13) via bolts, and the DCS system is electrically connected to the electronic water level gauge (3) and the emergency drain electric valve (13).

3. The dispersedly arranged adjustable heat dissipation water seal according to claim 1, characterized in that: Water seal air release valves (12) are installed on the upper ends of the fixed first-level water seal (7), the fixed second-level water seal (8), the fixed third-level water seal (9) and the fixed fourth-level water seal (10).

4. The dispersedly arranged adjustable heat dissipation water seal according to claim 1, characterized in that: The fixed primary water seal (7) is connected to a water seal water replenishment valve (1).

5. The dispersedly arranged adjustable heat dissipation water seal according to claim 1 is characterized in that: Cooling jackets (28) are installed on the outside of the fixed primary water seal (7), the fixed secondary water seal (8), the fixed tertiary water seal (9) and the fixed quaternary water seal (10); the cooling jackets (28) between the fixed primary water seal (7), the fixed secondary water seal (8), the fixed tertiary water seal (9) and the fixed quaternary water seal (10) are connected in sequence; a water seal cooling water inlet valve (14) is arranged above the cooling jacket (28) on the fixed primary water seal (7); and a water seal cooling water outlet valve (15) is arranged above the cooling jacket (28) on the fixed quaternary water seal (10).

6. The dispersedly arranged adjustable heat dissipation water seal according to claim 5, characterized in that: The lower end of the cooling jacket (28) on the fixed primary water seal (7) is connected to a water seal drain valve (20).

7. The dispersedly arranged adjustable heat dissipation water seal according to claim 1, characterized in that: The adjustable water seal assembly comprises an adjustable water seal assembly housing (26), an upper seal (31), a guide ring (30), a stretching rod (22), a lower seal (23), and an actuator (24); a stretching rod (22) is installed in the adjustable water seal assembly housing (26); a guide ring (30) is arranged outside the stretching rod (22); the guide ring (30) is slidably connected to the inner cavity of the adjustable water seal assembly housing (26); an upper seal (31) and a lower seal (23) are respectively installed between the upper and lower sides of the stretching rod (22) and the inner cavity of the adjustable water seal assembly housing (26); and an actuator (24) for driving the stretching rod (22) to move up and down is connected to the bottom of the adjustable water seal assembly housing (26) through bolts.

8. The dispersedly arranged adjustable heat dissipation water seal according to claim 7, characterized in that: The outer side of the adjustable water seal assembly housing (26) is connected to a base (25) via bolts.

9. The dispersedly arranged adjustable heat dissipation water seal according to claim 1, characterized in that: A main line U-shaped water seal (5) is installed on the main line pipe (27) of the shaft seal heater (2).

Images