Steam turbine regenerative efficiency-increasing system with zero output of low-pressure cylinder
By adding a steam source and a condensate drain unit to the low-pressure cylinder zero-output turbine regenerative efficiency improvement system, the overload problem caused by the low inlet water temperature of the low-pressure heater was solved, achieving safe operation and efficiency improvement.
Patent Information
- Application Number
- CN202423236098.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-11-18
- Estimated Expiration
- 2034-12-27
AI Technical Summary
In existing technologies, the low inlet water temperature of the low-pressure heater leads to overload, resulting in overspeed and vibration. Furthermore, the low steam intake of the low-pressure cylinder causes significant heat loss, making it impossible to achieve staged gravity flow. Consequently, the heat network condensate cooler cannot fully absorb the heat from the condensate.
A turbine regenerative efficiency improvement system with zero output in the low-pressure cylinder was designed. By connecting the deaerator, the first and second low-pressure heaters, the extraction unit, the condensing unit, and the condensate drain unit, the system increases the steam source, controls the temperature rise, increases the condensate volume, absorbs heat from the condensate drain, prevents overspeed and vibration, and increases the inlet water temperature.
This avoids high-temperature condensate from directly entering the condenser, reduces the condenser's heat load, ensures the safe operation of the low-pressure rotor, recovers the heat from the condensate, and improves the efficiency of the unit's regenerative system.
Smart Images
Figure CN223562877U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the heat recovery system technical field of thermal power plant, concretely relates to low pressure cylinder zero output's steam turbine heat recovery efficiency system. BACKGROUND
[0002] The average utilization hours of coal-fired units of most enterprises are low, and the combined heat and power units need to participate in deep peak shaving, but it is required to take measures from the load side, power supply side and power grid side, and fully tap the peak shaving capacity of the existing system. Since the existing system has been put into operation, the five-stage steam extraction has exceeded the speed of the inlet pipeline of the No. 5 low-pressure heater, the maximum temperature rise of the No. 5 low-pressure heater reaches nearly 70℃, and the heater body vibrates, which brings safety hazards. The low-pressure heater cannot realize step-by-step self-flowing, the heat loss is large, and the heat drain cooler of the heat supply network in operation cannot fully absorb the heat drain. Due to the small steam inlet amount of the low-pressure cylinder, the corresponding low-pressure heater has no steam source, the condensate temperature drops sharply, the water inlet temperature of the heater corresponding to the medium-pressure cylinder is low, and the low-pressure heater is overloaded. SUMMARY
[0003] The utility model discloses a low pressure cylinder zero output's steam turbine heat recovery efficiency system, solve the problem that the heater water inlet temperature is low in prior art and cause low pressure heater overload.
[0004] The utility model discloses a low pressure cylinder zero output's steam turbine heat recovery efficiency system, solve the problem that the heater water inlet temperature is low in prior art and cause low pressure heater overload.
[0005] The utility model discloses a low pressure cylinder zero output's steam turbine heat recovery efficiency system, solve the problem that the heater water inlet temperature is low in prior art and cause low pressure heater overload.
[0006] The first steam extraction unit comprises a first steam extraction pipe, the first steam extraction pipe is connected with the first low-pressure heater, the pipe body of the first steam extraction pipe is sequentially connected with a five-stage steam extraction electric valve, a five-stage steam extraction check valve and a five-stage steam inlet electric adjustment valve, and the five-stage steam inlet electric adjustment valve is arranged close to the first low-pressure heater.
[0007] The second steam extraction unit comprises a second steam extraction pipe, the second steam extraction pipe is connected with the second low-pressure heater, the pipe body of the second steam extraction pipe is sequentially connected with a six-stage steam extraction electric valve and a six-stage steam extraction check valve, and the six-stage steam extraction check valve is arranged close to the second low-pressure heater.
[0008] The condensing unit comprises a condensing pipe, two condensing pipes are connected with the first low-pressure heater and the second low-pressure heater respectively, the end of the condensing pipe is connected with a condenser, the pipe body of the condensing pipe is sequentially connected with a first low-pressure heater emergency drain hand valve, a low-pressure heater emergency drain valve and a second low-pressure heater emergency drain hand valve, and the second low-pressure heater emergency drain hand valve is arranged close to the condenser.
[0009] The drain unit comprises a drain pipe, two ends of the drain pipe are connected with a water removal pipe and a water connection pipe respectively, the pipe body of the drain pipe is connected with a low-pressure heater drain pump, the pipe body of the drain pipe is connected with a low-pressure heater drain pump inlet hand valve, the low-pressure heater drain pump inlet hand valve is arranged between the low-pressure heater drain pump and the connection point of the drain pipe and the water removal pipe, and the pipe body of the drain pipe is sequentially connected with a low-pressure heater drain pump outlet check valve and a low-pressure heater drain pump outlet electric valve.
[0010] The pipe body of the water removal pipe is sequentially connected with a second low-pressure heater normal drain valve front hand valve, a second low-pressure heater normal drain valve and a second low-pressure heater normal drain valve rear hand valve, the second low-pressure heater normal drain valve front hand valve is arranged close to the second low-pressure heater, and the connection point of the drain pipe and the water removal pipe is arranged between the second low-pressure heater normal drain valve front hand valve and the second low-pressure heater normal drain valve.
[0011] The pipe body of the connection pipe is sequentially connected with a first low-pressure heater normal drain valve front hand valve, a first low-pressure heater normal drain valve and a first low-pressure heater normal drain valve rear hand valve, and the first low-pressure heater normal drain valve front hand valve is arranged close to the first low-pressure heater.
[0012] The pipe body of the pipeline is connected with a deaerator water inlet check valve and a low-pressure heater water outlet electric valve, the deaerator water inlet check valve is arranged close to the deaerator, the pipe body of the pipeline is connected with a condensate pipe, the connection point of the condensate pipe and the pipeline is arranged between the deaerator water inlet check valve and the first low-pressure heater water outlet electric valve, the pipe body of the condensate pipe is connected with a low-pressure heater water side bypass electric valve, and the low-pressure heater water side bypass electric valve is arranged close to the pipeline.
[0013] The pipe body of the condensate pipe is connected with a branch pipe, the branch pipe is connected with the second low-pressure heater away from the pipe body of the condensate pipe, and the pipe body of the branch pipe is connected with a second low-pressure heater water inlet electric valve.
[0014] The steam turbine regenerative efficiency system of the low-pressure cylinder zero output can avoid that high-temperature drain of two low-pressure heaters directly enters the condenser, reduces the heat load of the condenser, can obtain higher vacuum, is favorable for safe operation of the low-pressure rotor under the zero output working condition, recovers the heat of high-temperature drain, and improves the efficiency of the regenerative system of the unit.
[0015] The steam turbine regenerative efficiency system of the low-pressure cylinder zero output can avoid that high-temperature drain of two low-pressure heaters directly enters the condenser, reduces the heat load of the condenser, can obtain higher vacuum, is favorable for safe operation of the low-pressure rotor under the zero output working condition, recovers the heat of high-temperature drain, and improves the efficiency of the regenerative system of the unit. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1The utility model discloses a low-pressure cylinder zero output steam turbine regenerative efficiency system structure diagram.
[0017] In the drawing: 1. five section steam extraction electric valve, 2. five section steam check valve, 3. five section admission electric regulating valve, 4. six section steam extraction electric valve, 5. six section steam check valve, 6. deaerator water inlet check valve, 7. first low pressure heater outlet electric valve, 8. first low pressure heater normal drain valve front manual valve, 9. first low pressure heater normal drain valve, 10. first low pressure heater normal drain valve rear manual valve, 11. first low pressure heater emergency drain hand valve, 12. low pressure heater emergency drain regulating valve, 13. second low pressure heater emergency drain hand valve, 14. second low pressure heater normal drain valve front manual valve, 15. second low pressure heater normal drain valve, 16. second low pressure heater normal drain valve rear manual valve, 17. deaerator, 18. first low pressure heater, 19. second low pressure heater, 20. second low pressure heater water inlet electric valve, 21. low pressure heater drain pump inlet hand valve, 22. low pressure heater drain pump, 23. low pressure heater drain pump outlet check valve, 24. low pressure heater drain pump outlet electric valve, 25. low pressure heater water side bypass electric valve, 26. pipeline, 27. connecting pipe, 28. water removal pipe, 29. water connection pipe, 30. first steam extraction pipe, 31. second steam extraction pipe, 32. condensing pipe, 33. drain pipe, 34. condensate pipe, 35. branch pipe. DETAILED DESCRIPTION
[0018] The utility model will be explained in detail below in connection with the drawings and specific embodiment.
[0019] The utility model provides a low-pressure cylinder zero output steam turbine regenerative efficiency system, as Figure 1 As shown, the deaerator 17 is connected with the first low-pressure heater 18 through the pipeline 26, the first low-pressure heater 18 is connected with the second low-pressure heater 19 through the connecting pipe 27, the second low-pressure heater 19 is connected with the water removal pipe 28, the first low-pressure heater 18 and the second low-pressure heater 19 are connected with the first steam extraction unit and the second steam extraction unit respectively, the first low-pressure heater 18 and the second low-pressure heater 19 are all connected with the condensing unit, the water removal pipe 28 and the water connection pipe 29 are connected with the drain unit between them. Connecting the first steam extraction unit and the second steam extraction unit to the first low-pressure heater 18 and the second low-pressure heater 19 respectively, adding steam source to the two heaters, then controlling temperature rise, preventing five extraction overspeed, improving condensate quantity by setting the drain unit, absorbing drain heat, improving the water inlet temperature of the second low-pressure heater 19, then improving the water inlet temperature of the first low-pressure heater 18, reducing the load of the first low-pressure heater 18, solving the problem of overspeed and vibration.
[0020] Example 1
[0021] The low-pressure cylinder zero-power steam turbine heat recovery efficiency system comprises a deaerator 17, the deaerator 17 is connected with a first low-pressure heater 18 through a pipeline 26, the first low-pressure heater 18 is connected with a second low-pressure heater 19 through a connecting pipe 27, the second low-pressure heater 19 is connected with a water removal pipe 28, the first low-pressure heater 18 and the second low-pressure heater 19 are respectively connected with a first steam extraction unit and a second steam extraction unit, the first low-pressure heater 18 and the second low-pressure heater 19 are both connected with a condensing unit, and the first low-pressure heater 18 and the second low-pressure heater 19 are also connected with a water connection pipe 29, and the water removal pipe 28 and the water connection pipe 29 are connected with a drain unit.
[0022] The first steam extraction unit comprises a first steam extraction pipe 30, the first steam extraction pipe 30 is connected with the first low-pressure heater 18, the pipe body of the first steam extraction pipe 30 is sequentially connected with a five-stage steam extraction electric valve 1, a five-stage steam extraction check valve 2 and a five-stage steam inlet electric adjustment valve 3, and the five-stage steam inlet electric adjustment valve 3 is arranged close to the first low-pressure heater 18.
[0023] The second steam extraction unit comprises a second steam extraction pipe 31, the second steam extraction pipe 31 is connected with the second low-pressure heater 19, the pipe body of the second steam extraction pipe 31 is sequentially connected with a six-stage steam extraction electric valve 4 and a six-stage steam extraction check valve 5, and the six-stage steam extraction check valve 5 is arranged close to the second low-pressure heater 19. The second steam extraction pipe 31 is steam-inlet, and is steam source of the second low-pressure heater 19.
[0024] Embodiment 2
[0025] The low-pressure cylinder zero-power steam turbine heat recovery efficiency system comprises a deaerator 17, the deaerator 17 is connected with a first low-pressure heater 18 through a pipeline 26, the first low-pressure heater 18 is connected with a second low-pressure heater 19 through a connecting pipe 27, the second low-pressure heater 19 is connected with a water removal pipe 28, the first low-pressure heater 18 and the second low-pressure heater 19 are respectively connected with a first steam extraction unit and a second steam extraction unit, the first low-pressure heater 18 and the second low-pressure heater 19 are both connected with a condensing unit, and the first low-pressure heater 18 and the second low-pressure heater 19 are also connected with a water connection pipe 29, and the water removal pipe 28 and the water connection pipe 29 are connected with a drain unit.
[0026] The condensing unit comprises a condensing pipe 32, two condensing pipes 32 are respectively connected with the first low-pressure heater 18 and the second low-pressure heater 19, the end of the condensing pipe 32 is connected with a condenser, the pipe body of the condensing pipe 32 is sequentially connected with a first low-pressure heater emergency drain hand valve 11, a low-pressure heater emergency drain valve 12 and a second low-pressure heater emergency drain hand valve 13, and the second low-pressure heater emergency drain hand valve 13 is arranged close to the condenser. The two heaters are connected through the condensing pipe, and the condensing is connected with the condenser.
[0027] Embodiment 3
[0028] The low-pressure cylinder zero-power steam turbine heat recovery system includes a deaerator 17, the deaerator 17 is connected with a first low-pressure heater 18 through a pipeline 26, the first low-pressure heater 18 is connected with a second low-pressure heater 19 through a connecting pipe 27, the second low-pressure heater 19 is connected with a water removal pipe 28, the first low-pressure heater 18 and the second low-pressure heater 19 are respectively connected with a first steam extraction unit and a second steam extraction unit, the first low-pressure heater 18 and the second low-pressure heater 19 are both connected with a condensing unit, the first low-pressure heater 18 and the second low-pressure heater 19 are further connected with a water connection pipe 29, and the water removal pipe 28 and the water connection pipe 29 are connected with a drain unit.
[0029] The drain unit includes a drain pipe 33, both ends of the drain pipe 33 are respectively connected with the water removal pipe 28 and the water connection pipe 29, the drain pipe 33 is connected with a low-pressure heater drain pump 22, the drain pipe 33 is connected with a low-pressure heater drain pump inlet hand valve 21, the low-pressure heater drain pump inlet hand valve 21 is arranged between the low-pressure heater drain pump 22 and the connection point of the drain pipe 33 and the water removal pipe 28, and the drain pipe 33 is sequentially connected with a low-pressure heater drain pump outlet check valve 23 and a low-pressure heater drain pump outlet electric valve 24, and the low-pressure heater drain pump outlet check valve 23 is arranged close to the low-pressure heater drain pump 22. The drain unit is used for heat recovery, the low-pressure heater drain pump inlet hand valve 21 is arranged on the drain pipe 33, so that the system can be isolated for maintenance, the low-pressure heater drain pump 22 adopts a variable frequency regulation mode, and the variable frequency automatic regulation control of the low-pressure heater liquid level is realized through DCS configuration.
[0030] Embodiment 4
[0031] The low-pressure cylinder zero-power steam turbine heat recovery system includes a deaerator 17, the deaerator 17 is connected with a first low-pressure heater 18 through a pipeline 26, the first low-pressure heater 18 is connected with a second low-pressure heater 19 through a connecting pipe 27, the second low-pressure heater 19 is connected with a water removal pipe 28, the first low-pressure heater 18 and the second low-pressure heater 19 are respectively connected with a first steam extraction unit and a second steam extraction unit, the first low-pressure heater 18 and the second low-pressure heater 19 are both connected with a condensing unit, the first low-pressure heater 18 and the second low-pressure heater 19 are further connected with a water connection pipe 29, and the water removal pipe 28 and the water connection pipe 29 are connected with a drain unit.
[0032] The pipe body of the water removal pipe 28 is sequentially connected with a second low-pressure heater normal drain valve front hand valve 14, a second low-pressure heater normal drain valve 15 and a second low-pressure heater normal drain valve rear hand valve 16, the second low-pressure heater normal drain valve front hand valve 14 is arranged close to the second low-pressure heater 19, and the connection point of the drain pipe 33 and the water removal pipe 28 is arranged between the second low-pressure heater normal drain valve front hand valve 14 and the second low-pressure heater normal drain valve 15. The water removal pipe is connected with the next low-pressure heater, and plays a connecting role for the entire network.
[0033] The pipe body of the connecting pipe 27 is sequentially connected with a first low-pressure heater normal drain valve front manual valve 8, a first low-pressure heater normal drain valve 9 and a first low-pressure heater normal drain valve rear manual valve 10, and the first low-pressure heater normal drain valve front manual valve 8 is arranged close to the first low-pressure heater 18.
[0034] The pipe body of the pipe 26 is connected with a deaerator water inlet check valve 6 and a first low-pressure heater water outlet electric valve 7, the deaerator water inlet check valve 6 is arranged close to the deaerator 17, the pipe body of the pipe 26 is connected with a condensate water pipe 34, the connecting point of the condensate water pipe 34 and the pipe is arranged between the deaerator water inlet check valve 6 and the first low-pressure heater water outlet electric valve 7, and the pipe body of the condensate water pipe 34 is connected with a low-pressure heater water side bypass electric valve 25, and the low-pressure heater water side bypass electric valve 25 is arranged close to the pipe 26. The deaerator water inlet check valve 6 prevents water from entering the deaerator 17.
[0035] The pipe body of the condensate water pipe 34 is connected with a branch pipe 35, the branch pipe 35 is connected with a second low-pressure heater 19 away from the pipe body of the condensate water pipe 34, and the pipe body of the branch pipe 35 is connected with a second low-pressure heater water inlet electric valve 20. Through the branch pipe 35, condensate water enters the second low-pressure heater 19.
[0036] The working process of the low-pressure cylinder zero output steam turbine regenerative efficiency improving system is as follows:
[0037] When the zero output mode under the unit heating mode is put into operation, the low-pressure heater drain pump inlet hand valve 21 is opened, the low-pressure heater drain pump 22 is started in frequency conversion, the low-pressure heater drain pump outlet electric valve 24 is opened, the frequency of the low-pressure heater drain pump 22 is increased, and the outlet pressure of the low-pressure heater drain pump 22 is checked; when the outlet pressure of the low-pressure heater drain pump 22 is close to the condensate water pressure, the second low-pressure heater normal drain valve 15 is slowly closed, the frequency of the low-pressure heater drain pump 22 is increased, the water level of the second low-pressure heater 19 is kept unchanged, until the second low-pressure heater normal drain valve 15 is fully closed, the low-pressure heater drain pump 22 is checked to be in normal operation, the liquid level of the second low-pressure heater 19 is stable, and the low-pressure heater drain pump 22 frequency conversion automatic control is put into the liquid level of the second low-pressure heater 19. When the zero output mode under the unit heating mode is withdrawn from operation, the second low-pressure heater 19 normal drain and the low-pressure heater drain pump 22 can be switched to the reverse direction.
[0038] The low-pressure cylinder zero output steam turbine regenerative efficiency improving system avoids that high-temperature drain directly enters the condenser due to the fact that the first low-pressure heater and the second low-pressure heater drain cannot be gradually self-flowing because of the removal of the low-pressure cylinder drain, thereby causing the unit efficiency to decrease.
Claims
1. A low-pressure cylinder zero-out regenerative efficiency improvement system for a steam turbine, characterized in that, The device comprises a deaerator (17), the deaerator (17) is connected with a first low-pressure heater (18) through a pipeline (26), the first low-pressure heater (18) is connected with a second low-pressure heater (19) through a connecting pipeline (27), the second low-pressure heater (19) is connected with a water removal pipeline (28), the first low-pressure heater (18) and the second low-pressure heater (19) are respectively connected with a first steam extraction unit and a second steam extraction unit, the first low-pressure heater (18) and the second low-pressure heater (19) are both connected with a condensing unit, a water connection pipeline (29) is further connected between the first low-pressure heater (18) and the second low-pressure heater (19), and a drain unit is connected between the water removal pipeline (28) and the water connection pipeline (29).
2. The low-pressure cylinder zero-output steam turbine heat recovery efficiency improvement system according to claim 1, characterized by, The first steam extraction unit comprises a first steam extraction pipeline (30), the first steam extraction pipeline (30) is connected with the first low-pressure heater (18), and the pipeline body of the first steam extraction pipeline (30) is sequentially connected with five steam extraction electric valves (1), five steam extraction check valves (2) and five steam inlet electric adjusting valves (3); the five steam inlet electric adjusting valves (3) are arranged close to the first low-pressure heater (18).
3. The low-pressure cylinder zero-output steam turbine heat recovery efficiency improvement system according to claim 1, characterized by, The second steam extraction unit comprises a second steam extraction pipeline (31), the second steam extraction pipeline (31) is connected with the second low-pressure heater (19), and the pipeline body of the second steam extraction pipeline (31) is sequentially connected with six steam extraction electric valves (4) and six steam extraction check valves (5); the six steam extraction check valves (5) are arranged close to the second low-pressure heater (19).
4. The low-pressure cylinder zero-output steam turbine heat recovery efficiency improvement system according to claim 1, characterized by, The condensing unit comprises a condensing pipeline (32), two condensing pipelines (32) are respectively connected with the first low-pressure heater (18) and the second low-pressure heater (19), the end of the condensing pipeline (32) is connected with a condenser, and the pipeline body of the condensing pipeline (32) is sequentially connected with a first low-pressure heater emergency drain hand valve (11), a low-pressure heater emergency drain regulating valve (12) and a second low-pressure heater emergency drain hand valve (13); the second low-pressure heater emergency drain hand valve (13) is arranged close to the condenser.
5. The low-pressure cylinder zero-output steam turbine heat recovery efficiency improvement system according to claim 1, characterized by, The drain unit comprises a drain pipeline (33), two ends of the drain pipeline (33) are respectively connected with the water removal pipeline (28) and the water connection pipeline (29), the pipeline body of the drain pipeline (33) is connected with a low-pressure heater drain pump (22), the pipeline body of the drain pipeline (33) is connected with a low-pressure heater drain pump inlet hand valve (21), the low-pressure heater drain pump inlet hand valve (21) is arranged between the low-pressure heater drain pump (22) and the connection point of the drain pipeline (33) and the water removal pipeline (28), the pipeline body of the drain pipeline (33) is sequentially connected with a low-pressure heater drain pump outlet check valve (23) and a low-pressure heater drain pump outlet electric valve (24); the low-pressure heater drain pump outlet check valve (23) is arranged close to the low-pressure heater drain pump (22).
6. The low-pressure cylinder zero-output steam turbine heat recovery efficiency improvement system according to claim 5, characterized by, The pipe body of the drain pipe (28) is sequentially connected with a second low-pressure heater normal drain valve front manual valve (14), a second low-pressure heater normal drain valve (15) and a second low-pressure heater normal drain valve rear manual valve (16), the second low-pressure heater normal drain valve front manual valve (14) is arranged close to the second low-pressure heater (19), and the connection point of the drain pipe (33) and the drain pipe (28) is arranged between the second low-pressure heater normal drain valve front manual valve (14) and the second low-pressure heater normal drain valve (15).
7. The low-pressure cylinder zero-output steam turbine heat recovery efficiency improvement system according to claim 1, characterized by, The pipe body of the connecting pipe (27) is sequentially connected with a first low-pressure heater normal drain valve front manual valve (8), a first low-pressure heater normal drain valve (9) and a first low-pressure heater normal drain valve rear manual valve (10), and the first low-pressure heater normal drain valve front manual valve (8) is arranged close to the first low-pressure heater (18).
8. The low-pressure cylinder zero-output steam turbine heat recovery efficiency improvement system according to claim 1, characterized by, The pipe body of the pipeline (26) is connected with a deaerator water inlet check valve (6) and a first low-pressure heater water outlet electric valve (7), the deaerator water inlet check valve (6) is arranged close to the deaerator (17), the pipe body of the pipeline (26) is connected with a condensate pipe (34), the connection point of the condensate pipe (34) and the pipeline is arranged between the deaerator water inlet check valve (6) and the first low-pressure heater water outlet electric valve (7), the pipe body of the condensate pipe (34) is connected with a low-pressure heater water side bypass electric valve (25), and the low-pressure heater water side bypass electric valve (25) is arranged close to the pipeline (26).
9. The low-pressure cylinder zero-output steam turbine heat recovery efficiency improvement system according to claim 8, characterized by, The pipe body of the condensate pipe (34) is connected with a branch pipe (35), the pipe body of the branch pipe (35) is connected with the second low-pressure heater (19) away from the pipe body of the condensate pipe (34), and the pipe body of the branch pipe (35) is connected with a second low-pressure heater water inlet electric valve (20).