JP5188607B2 - Isolation method for maintenance in power generation facilities - Google Patents

Description

  The present invention relates to an isolation method during maintenance in a power generation facility having a steam turbine system.

  Before explaining the isolation method at the time of maintenance in a power generation facility, a general power generation facility will be described taking a thermal power generation facility as an example. As shown in FIG. 1, the thermal power generation facility includes a boiler 10 that heats water to make steam, steam turbines 20, 21, 22, 23 that are driven by steam generated in the boiler 10, and the steam turbine A generator 30 that generates power by being driven by 20 to 23; a condenser 40 that cools steam discharged from the steam turbines 20 to 23 into water (saturated water); and the condenser 40 Water supply means (a booster water supply pump 51 and a boiler water supply pump 52) 50 for supplying the obtained water to the boiler 10 is provided.

  In the thermal power generation facility, when performing regular maintenance (maintenance, inspection, or repair), it is necessary to stop a predetermined pump from a plurality of water supply pumps that supply high pressure heating water to the boiler 10 or the like. In this case, an operation of isolating (separating) the piping system connected to the pump from the water supply pump of another system in a process flow is performed.

  For example, when maintaining the booster feed pump 51 that supplies the boiler 10 with the condensate from the condenser 40 together with the boiler feed pump 52, first, the steam system and the water system of the boiler feed pump 52 are stopped, and the boiler is turned off. The feed water pump 52 is isolated from the steam system and the water system of the boiler feed pump 52, and the booster feed pump 51 is maintained after the isolation is completed. At the time of isolation, there is no partition valve between the boiler feed pump 52 and the booster feed pump 51 arranged upstream of the boiler feed pump 52, so that the booster feed pump 51 to the boiler feed pump 52 are arranged in a wide range. Each valve is opened and closed according to the procedure.

  In addition, as an isolation system when maintaining the boiler feed pump 52, for example, the boiler feed pump 52 is turned to cool the turbine T of the boiler feed pump 52 that is at a high temperature to a predetermined temperature. A shaft seal water supply system for supplying low temperature flush water (cooling water) to the through-flow portion so that the high temperature water inside the casing does not leak to the outside by the isolating means after being supplied to the rotor of the boiler feed pump 52 and cooled. Therefore, it is known that the boiler feed water pump 52 is separated and the boiler feed water pump 52 is drained (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2007-100597

  However, as described above, the isolation rate for maintaining the booster feed pump 51 has a wide operation range from the boiler feed pump 52 to the booster feed pump 51, and opens and closes many valves. Is needed.

  Further, during maintenance, the steam system and the water system of the boiler feed pump 52 are stopped (as a result, a vacuum drop occurs inside the turbine of the boiler feed pump 52). Although it is necessary to return the inside of the turbine of the pump 52 to a vacuum, this may take time.

  That is, when the exhaust chamber of the turbine T of the boiler feed water pump 52 is vacuum-increased (decompressed), after the vacuum increase (decompression) of the condenser 40 is completed, the air in the exhaust chamber of the turbine T of the boiler feed pump 52 is removed. The exhaust valve X disposed in the pipe connecting the turbine of the boiler feed pump 52 and the condenser 40 is opened, and air is extracted by the condenser 40. If there is (inhalation of the atmosphere to the boiler feed pump 52 side), the air inflow from the turbine T of the boiler feed pump 52 to the condenser 40 is reduced, and it takes time to raise the vacuum.

  When the exhaust valve X is opened in advance without reducing the vacuum difference between the exhaust chamber of the turbine T of the boiler feed pump 52 and the condenser 40, the degree of vacuum of the condenser 40 is increased. It may be greatly reduced. In particular, when maintenance is performed during operation of the steam turbines 20 to 23, the vacuum in the exhaust chamber of the turbine T of the boiler feed pump 52 is broken (pressure is increased from a vacuum state to atmospheric pressure), and then the vacuum is increased (reduced pressure). There is a possibility that the degree of vacuum reduction of the condenser 40 will increase, causing a temperature increase in the exhaust chamber of the condenser 40, and the steam turbines 20 to 23 to stop (unit trip). For this reason, it is necessary to constantly monitor the vacuum value of the condenser 40.

  Therefore, the present invention provides an isolation method during maintenance in a power generation facility that reduces the operation range of the boiler water pump isolation when performing maintenance of the booster water pump and reduces time and work personnel. The issue is to provide.

  The isolation method during maintenance in the power generation facility according to the present invention is a condensate / water supply system for supplying steam to the boiler 10 with the condensate condensed by the condenser 40 after working the steam generated in the boiler 10. WLa, WLb, and a shaft seal water supply system WLc that supplies a part of the condensate as shaft seal water of the water supply means 50 disposed in the condensate / water supply systems WLa, WLb, and the water supply means 50 includes: In a power generation facility having a booster water supply pump 51 and a boiler water supply pump 52, and a connection pipe 500 that connects the outlet side of the booster water supply pump 51 and the inlet side of the boiler water supply pump 52 from above, the boiler water supply pump 52 is While turning, steam-sealing, and then supplying the sealed water from the condenser 40 into the boiler feed pump 52, the outlet of the boiler feed pump 52 In addition, the flow of water from the inlet side of the boiler feed pump 52 is blocked, and then, in the booster feed pump 51, it is confirmed that there is no flow of water from the boiler feed pump 52, and then the booster feed pump 51 It is characterized by the fact that maintenance is performed.

  According to this configuration, only the water system of the boiler feed pump 52 is turned by turning the boiler feed pump 52 (stopping the turbine of the boiler feed pump 52 and rotating the turbine rotor at a low speed) and steam sealing. Will be isolated. Therefore, since there is no isolation for the booster feed pump 51, the work process and personnel can be reduced, and workability can be greatly improved. On the other hand, since the steam system of the boiler feed pump 52 is utilized, it is possible to prevent a vacuum drop in the condenser 40 and to prevent a unit trip due to the vacuum drop. That is, it is not necessary to constantly monitor the vacuum value of the condenser 40, and the burden on the operator is reduced.

  Further, since the flow of water from the outlet side of the boiler feed pump 52 is blocked and the flow of water from the entrance side of the boiler feed pump 52 is blocked, there is no flow from the boiler feed pump 52 to the booster feed pump 51, and the booster feed pump 51 can be easily maintained. Moreover, the boiler feed water pump 52 can be efficiently cooled by utilizing sealing from the shaft seal water supply system WLc as cooling water for the boiler feed water pump 52. Furthermore, since the steam system of the boiler feed pump 52 is utilized at the time of restoration, there is no vacuum drop of the condenser 40. That is, the recovery time can be shortened because there is no vacuum difference between the exhaust chamber of the turbine of the boiler feed pump 52 and the condenser 40.

  In addition, according to the present invention, it is possible to adopt a configuration in which the inside of the boiler feed pump 52 is filled with sealed water after blocking the flowing water on the outlet side and the inlet side of the boiler feed pump 52. .

  According to such a configuration, after the outlet side and the inlet side of the boiler feed pump 52 are isolated, that is, the boiler feed pump 52 is separated from the condensate / water feed systems WLa and WLb, and the boiler feed pump is sealed by sealing water. By making the inside of 52 full, the inside of the boiler feed pump 52 can be efficiently cooled. That is, cooling is effectively performed by continuing cooling until the inside of the boiler feed pump 52 becomes full.

  In addition, according to the present invention, it is possible to adopt a configuration in which the casing of the boiler feed pump 52 is vented after the outlet water and the inlet side of the boiler feed pump 52 are blocked.

  According to such a configuration, the casing of the boiler feed pump 52 is efficiently cooled by removing the air from the casing of the boiler feed pump 52 with the boiler feed pump 52 disconnected from the condensate / feed systems WLa and WLb. be able to.

  Further, according to the present invention, the connection pipe 500 is connected to a rotor balance pipe 501 that maintains the balance of the rotor of the boiler feed pump 52, and a blow hose 502 is connected to the rotor balance pipe 501. By confirming the flowing water from the blow hose 502, it is possible to adopt a configuration in which it is confirmed that the boiler feed pump 52 is filled with sealed water.

  According to such a configuration, the rotor balance pipe 501 connected to the boiler feed pump 52 and the blow hose 502 connected to the rotor balance pipe 501 are used as means for checking the full water state inside the boiler feed pump 52. Therefore, it can be confirmed with a simple configuration without significant changes in the configuration.

  In addition, according to the present invention, after the inside of the boiler feed pump 52 is maintained in a full state with sealed water, after blowing the section that blocks the flowing water on the outlet side and the inlet side of the boiler feed pump 52, The structure which performs the maintenance of the booster feed pump 51 can be adopted.

  According to such a configuration, since the boiler feed pump 52 is cooled using the sealed water and only the section in which the flowing water on the outlet side and the inlet side of the boiler feed pump 52 is blocked is blown, maintenance of the booster feed pump 51 is performed. The work up to is greatly improved.

  According to the present invention, the boiler feed water pump can be cooled by turning the steam of the boiler feed pump turbine and steam-sealed, while the steam system in the boiler feed pump is not isolated and only the water system is Since it is isolated, the operation range of the boiler feed pump isolation can be reduced, and time and labor can be reduced. Furthermore, since the steam system in the boiler feed pump is not isolated, it is not necessary to constantly monitor the vacuum value of the condenser, thereby reducing the burden on the operator.

  Moreover, at the time of restoration, it is only necessary to restore the water system of the boiler feed pump, that is, it is only necessary to operate each valve in the section where the outlet water and the inlet side of the boiler feed pump are blocked. Furthermore, since the steam system of the boiler feed pump is utilized, the vacuum value of the condenser does not decrease. That is, there is no difference in the degree of vacuum between the condenser and the exhaust chamber of the turbine of the boiler feed pump, and the recovery time can be greatly shortened.

The figure which shows schematic structure of the power generation equipment which concerns on one Embodiment of this invention. Schematic which shows the principal part of FIG. Schematic which showed the principal part of FIG. 1 in three dimensions.

  One embodiment of an isolation method at the time of maintenance in a power generation facility according to the present invention will be described with reference to FIGS. First, as a power generation facility, a thermal power generation facility in which a booster feed water pump and a boiler feed water pump are installed will be described as an example. As shown in FIG. 1, the thermal power generation facility 1 includes a boiler 10 that heats water to make steam, steam turbines 20, 21, 22, 23 that are driven by steam generated in the boiler 10, and the steam turbine From generator 30 which receives power of 20-23, and generates electricity, condenser 40 for cooling the steam discharged from steam turbines 20-23 into water (saturated water), and steam turbines 20-23 A low-pressure feed water heater 59 that heats the condensate obtained in the condenser 40, and a deaerator 60 that directly heats the water by steam and physically separates and removes dissolved gas contained in the water. And a high-pressure feed water heater 70 that heats water deaerated by the deaerator 60 by extraction from the steam turbines 20 to 23. Note that the low-pressure feed water heater 59 and the high-pressure feed water heater 70 have a plurality of heaters (not shown).

  Furthermore, the thermal power generation facility 1 includes a circulation pump 80 that supplies cooling water to the condenser 40, a condensate pump 53 that supplies the condensate obtained by the condenser 40 to the low-pressure feed water heater 59, and the boiler 10. A booster water supply pump 51 and a boiler water supply pump 52 are provided as water supply means 50 for supplying to the boiler.

  The thermal power generation facility 1 then supplies a condensate line WLa that connects the condenser 40 and the booster feed pump 51 to the water obtained by the condenser 40 to the booster feed pump 51 and the boiler feed pump 52; In order to supply water from the water system WLa to the boiler 10, the booster water supply pump 51, the water supply system WLb that connects the boiler water supply pump 52 and the boiler 10, and steam generated in the boiler 10 are steam turbines 20, 21, 22. The steam system SL is connected to the boiler 10 and the condenser 40 via the steam turbines 20 to 23 in order to supply the steam discharged from the steam turbines 20 to 23 to the condenser 40. .

  The boiler 10 includes an evaporator 11 that evaporates water supplied from the water supply system WLb, a superheater 12 that superheats the saturated steam evaporated by the evaporator 11, and an exhaust (from a high-pressure turbine described later) 20 ( And a reheater 13 that superheats (steam). And the boiler 10 which concerns on this embodiment supplies the steam superheated by the superheater 12 to the steam turbine (high pressure turbine) 20, and the steam superheated by the reheater 13 is another steam turbine (intermediate pressure turbine mentioned later). 21 is supplied.

  Specifically, the steam turbines 20, 21, 22, and 23 include a high-pressure turbine 20, an intermediate-pressure turbine 21, and a low-pressure turbine 22, 23. The high-pressure turbine 20 and the intermediate-pressure turbine 21 are provided one by one. Two low-pressure turbines 22 and 23 are provided.

  These steam turbines 20, 21, 22, and 23 are arranged in parallel so that the respective output shafts are coaxial in the order of the high-pressure turbine 20, the intermediate-pressure turbine 21, and the low-pressure turbines 22 and 23. It connects with the output shaft of the adjacent steam turbines 20-23. The generator 30 is disposed side by side with respect to the steam turbines 20 to 23, and the input shaft is connected to the output shaft of the low-pressure turbine 23. Thereby, the generator 30 receives the drive of the high pressure turbine 20, the intermediate pressure turbine 21, and the low pressure turbines 22 and 23 to generate power.

  The condenser 40 cools the exhaust (steam) of the steam turbines 22 and 23 into water, and in the present embodiment, steam from the steam turbines 22 and 23 (low-pressure turbines 22 and 23) is introduced. A housing 400 defining an internal space and a cooling pipe (not shown) disposed in the housing 400 for circulating cooling water from the circulation system RL, and cooling the steam introduced into the housing 400 It cools indirectly with the cooling water in a pipe | tube, and this condenses a vapor | steam to water.

  The booster feed pump 51 is provided to ensure the pushing pressure of the boiler feed pump 52, and is configured by an electric pump P that is driven by an electric motor. The booster water supply pump 51 employs a water seal system as a sealing method (shaft seal) between the casing and the shaft through-flow portion. This water sealing method is performed by a shaft cooling system WLd (see FIG. 2) that supplies low-temperature flush water (cooling water) to the flow-through portion so that high-temperature water inside the casing does not leak outside.

  The boiler feed water pump 52 is disposed on the downstream side of the booster feed water pump 51, and includes an electric pump P driven by an electric motor and a steam turbine pump T driven by steam. And in order to supply high pressure water to the boiler 10, the water supply pressurized by the booster water supply pump 51 is put into the casing and the impeller is rotated, and the water supply and the impeller pressed against the inner wall of the casing by centrifugal force Suction and discharge are performed using changes in the space surrounded by. Moreover, since the boiler feed pump 52 handles high-temperature water, a water seal system is adopted as a sealing method (shaft seal) between the casing and the shaft flow-through portion. This water-sealing method is performed by a sealed water supply system that supplies low-temperature pressure water (sealed water) to the flow-through portion so that high-temperature water inside the casing does not leak to the outside. The water is collected in the condenser 40 via the sealed water communication pipe 531 (see FIG. 2) and the sealed water collection tank (not shown) of the system WLc (see FIG. 2). The sealed water is also used as cooling water for the boiler feed pump 52.

  The feed water system WLb includes a high-pressure feed water heater 70 that heats the water fed by the booster feed water pump 51 and the boiler feed water pump 52 by extraction from the steam turbines 20, 21, 22, and 23.

  The steam system SL is based on the assumption that the steam turbines 20, 21, 22, and 23 are arranged as described above, the first steam line SL 1 that connects the boiler 10 and the intake side of the high-pressure turbine 20, and the high-pressure turbine 20. The second steam line SL2 connecting the exhaust side of the boiler 10 and the reheater 13 in the boiler 10, the third steam line SL3 connecting the reheater 13 and the intake side of the intermediate pressure turbine 21, and the intermediate pressure turbine 21 The fourth steam line SL4 connecting the exhaust side of the low-pressure turbines 22 and 23 and the intake side of the low-pressure turbines 22 and 23, and the fifth steam line SL5 connecting the exhaust side of the low-pressure turbines 22 and 23 and the condenser 40 are provided. .

  In addition, the steam system SL of the thermal power generation facility 1 according to the present embodiment is connected to the steam line SL1 to SL5 and the valve B from the first steam line SL1 that connects the boiler 10 and the high-pressure turbine 20. A bypass pipe SL6 that branches and connects to the condenser 40 is provided.

  The circulation system RL includes a water intake path 81 connected to a water source (the sea in this embodiment), a circulation pump 80 that supplies cooling water taken from the water source to the water intake path 81 to the condenser 40, and a condenser 40. And a water discharge passage 82 for returning the cooling water used for heat exchange (steam cooling) to the water source. In this embodiment, the water source of the circulation system RL is the sea. However, depending on the location conditions of the power generation facility 1, the river may be used as the water source of the circulation system RL.

  Here, the configuration of piping (hereinafter referred to as a piping group) connected to the booster feed pump 51 and the boiler feed pump 52 will be described with reference to FIGS. 2 and 3. The piping group is connected to the discharge side of the booster feed pump 51 and the suction side of the boiler feed pump 52 so as to straddle the discharge side of the booster feed pump 51 and the suction side of the boiler feed pump 52 from above. A suction pipe 511 connected to the deaerator 60 and the suction port of the booster feed pump 51, and a discharge pipe 521 connected to the discharge port of the boiler feed pump 52 and the high-pressure feed water heater 70. .

  A rotor balance pipe 501 that maintains the balance of the rotor of the boiler feed pump 52 is connected to a midway portion of the connection pipe 500 positioned above the booster feed pump 51 and the boiler feed pump 52 and the suction side of the boiler feed pump 52. Has been. In addition, a pair of sealed water supply pipes 530 and 530 that supply sealed water from the condenser 40 to the boiler feed pump 52 are connected to the boiler feed pump 52. In addition, the piping group includes a sealed water communication pipe 531 that collects the sealed water supplied to the boiler feed pump 52 in the condenser 40.

  The suction pipe 511 includes an inlet valve 511a that opens and closes the flow path from the deaerator 60, and a strainer S that removes impurities such as marine products and drifting foreign matter in front of the suction port of the booster feed pump 51. Yes. A strainer air vent pipe 5110 having a strainer air vent valve 5110a is connected to the suction pipe 511, and a strainer blow pipe 5111 having a strainer blow valve 5111a is connected to the strainer S.

  Pipes connected to the booster feed pump 51 include a casing air vent pipe 5112 having a casing air vent valve 5112a and a casing blow pipe 5113 having a casing blow valve 5113a. The mechanical seal flushing water inlet pipe 540 of the shaft cooling system WLd described above is provided with a mechanical seal flushing water inlet valve 540a, and the mechanical seal flushing water outlet pipe 541 is provided with a mechanical seal flushing water outlet valve 541a. The seal flushing air vent pipe 542 is provided with a mechanical seal flushing air vent valve 542a. The mechanical seal flushing water inlet pipe 540, the mechanical seal flushing water outlet pipe 541, and the mechanical seal flushing water air vent pipe 542 are connected to the mechanical cooler 55. Although not shown, the booster feed pump 51 is provided with a shaft cold water supply source valve and a shaft cold water return source valve.

  The boiler feed pump 52 has a discharge pipe 521 connected thereto, and an outlet valve pre-bleed pipe 5210, an outlet pipe drain pipe 5211, and an overheat prevention pipe 5212 are connected to the discharge pipe 521. The discharge pipe 521 is provided with an outlet valve 521a for supplying water to the high-pressure feed water heater 70, the outlet valve pre-bleeding pipe 5210 is provided with an outlet valve pre-bleeding valve 5210a, and the outlet pipe drain pipe 5211 is provided with an outlet. A pipe drain valve 5211a is provided. In addition, when the boiler feed pump 52 is shut off, the overheat prevention pipe 5212 prevents the power loss from flowing into heat, and the feed water temperature inside the boiler feed pump 52 rises. ing. The overheat prevention pipe 5212 is provided with an overheat prevention valve front valve 5212 a that prevents the high temperature water from the overheat prevention pipe 5210 from flowing back to the boiler feed pump 52. The overheat prevention pipe 5212 is provided with an overheat prevention pipe drain valve 5212b that discharges internal high-temperature water.

  The boiler feed pump 52 is connected with a warming pipe 5213 for warming up the hot water of the boiler feed pump 52 during operation in order to start quickly with respect to the boiler feed pump of the standby machine that is stopped. In addition, a casing air vent pipe 5214 is connected. The warming pipe 5213 is provided with a warming valve 5213a, and the casing air vent pipe 5214 is provided with a casing air vent valve 5214a. A casing blow pipe 5215 is connected to the warming pipe 5213, and a casing blow valve 5215 a is provided in the casing blow pipe 5215.

  Further, a rotor balance pipe 501 for maintaining the balance of the rotor is connected to the boiler feed pump 52, a pair of sealed water supply pipes 530 and 530 are connected, and a sealed water communication pipe 531 is connected to the connecting pipe 500. ing. The rotor balance pipe 501 has a rotor balance pipe pressure gauge detection pipe 5010, and confirms that the sealed water supplied to the boiler feed pump 52 is full in the rotor balance pipe pressure gauge detection pipe 5010. The blow water confirmation hose 502 is connected. The rotor balance piping pressure gauge detection piping 5010 includes a rotor balance piping pressure gauge detection piping original valve 5010a. In addition, a pair of seal water adjustment valve bypass valves 530a and 530a are arranged in the seal water supply pipes 530 and 530, and a pair of seal water minimum flow rate adjustment valves 530b and 530b are arranged in the bypass path. The sealed water communication pipe 531 is provided with a sealed water communication pipe blow valve 531a and a sealed water communication pipe blow valve front valve 531b.

  Next, an isolation method during maintenance in the booster feed pump 51 will be described. First, the turbine of the boiler feed water pump 52 is turned, and ground steam is supplied and steam sealed. Thereby, the vacuum drop of the condenser 40 is prevented, and monitoring of the vacuum value of the condenser 40 becomes unnecessary.

  Next, it is confirmed that the outlet valve 521a of the boiler feed pump 52 is fully closed, and water flowing from the outlet side is blocked. Then, the circuit breaker of the load center, which is electrically connected to the booster feed pump 51, is set to the “off” state (E lock), and the circuit breaker is removed from the power supply circuit (not shown). Then, the electromagnetic switch in the power circuit of the control center, which is electrically connected to the outlet valve 521a of the boiler feed pump 52, is opened (E lock), and the wiring circuit breaker is operated to “OFF”. (Not shown).

  Next, the warming valve 5213a that supplies high-temperature water from the boiler feed water pump 52 in operation to the boiler feed pump (not shown) of the standby machine that is stopped is fully closed. Then, the overheat prevention valve front valve 5212a for preventing the backflow of the high temperature water from the overheat prevention pipe 5212 is fully closed.

  Thereafter, the sealing water adjustment valve bypass valve (coupling side: suction side of the boiler feed pump 52) 530a and the sealing water adjustment valve bypass valve (anti-coupling side: discharge side of the boiler feed pump 52) 530a are adjusted and opened. Then, water is supplied to cool the boiler feed pump 52. By supplying this sealed water, the shaft of the boiler feed pump 52 is sealed, and cooling of the boiler feed pump 52 is started.

  Next, the inlet valve 511a of the boiler feed pump 52 is fully closed by a control switch (not shown), and a circuit breaker (not shown) electrically connected to the inlet valve 511a of the boiler feed pump 52 is provided. In the closed state, water flowing from the inlet side of the booster feed pump 51 is blocked. In addition, when fully closing the inlet valve 511a of the boiler feed pump 52, attention should be paid to flushing (water hammer).

  It is confirmed that the blow valve 531a of the sealed water communication pipe 531 located above the boiler feed pump 52 is fully open. On the other hand, the booster feed pump 51 is opened while adjusting the strainer blow valve 5111a to start cooling the booster feed pump 51. Then, the sealing water adjusting valve bypass valves 530a and 530a and the respective sealing water minimum flow rate adjusting valves 530b and 530b are adjusted to be opened to continue cooling the boiler feed pump 52. The temperature drop at this time was about 25 hours to 30 degrees per hour and took about 4 hours to drop to 143 degrees to 42 degrees.

  Thereafter, the detection pipe main valve 5010a for the rotor balance pipe pressure gauge of the boiler feed pump 52 is fully closed to connect the blow hose 502. On the other hand, the inside of the boiler feed pump 52 is opened by adjusting the minimum sealed water flow rate adjustment valve (coupling side) 530b and the minimum sealed water flow rate adjustment valve (anti-coupling side) 530b of the boiler feed pump 52. Fill up with water. At this time, it is confirmed that there is no running water from the sealed water communication pipe 531.

  Then, the overheat prevention pipe drain valve 5212b of the boiler feed pump 52 is fully opened, the outlet pipe drain valve 5211a of the boiler feed pump 52 is fully opened, and the casing air vent valve 5214a of the boiler feed pump 52 is fully opened. Further cooling of the boiler feed water pump 52 is continued. On the other hand, the rotor balance piping pressure gauge detection piping original valve 5010a is fully opened to confirm that there is no flowing water (back flow) from the boiler feed pump 52 to the booster feed pump 51.

  Next, the strainer air vent valve 5110a of the booster feed pump 51 is fully opened, and the strainer blow valve 5111a, the casing air vent valve 5112a, and the casing blow valve 5113a are each fully opened to continue cooling the booster feed pump 51. It is confirmed that there is no running water from the casing blow valve 5113a.

  And the outlet valve front air vent valve 5210a of the boiler feed pump 52 is fully opened to complete the cooling of the boiler feed pump 52.

  Finally, the booster feed pump 51 is isolated from the shaft cooling system of the booster feed pump 51. That is, the shaft cold water supply source valve (not shown) of the booster feed pump 51 is fully closed, and the shaft cold water return source valve (not shown) of the booster feed pump 51 is fully closed. The mechanical seal flushing water inlet valve 540a of the booster feed pump 51 is fully closed, and the mechanical seal flushing water outlet valve 541a of the booster feed pump 51 is fully closed. Finally, the mechanical seal flushing water air vent valve 542a of the booster feed pump 51 is fully opened. And the booster feed pump 51 is maintained.

  Next, the recovery operation will be described. First, the shaft cold water supply source valve (not shown) of the booster feed pump 51 is fully opened from fully closed, and the shaft cold water return source valve (not shown) of the booster feed pump 51 is fully opened from fully closed, The mechanical seal flushing water inlet valve 540a of the booster feed pump 51 is fully opened from fully closed, and the mechanical seal flushing water outlet valve 541a of the booster feed pump 51 is fully opened from fully closed. Thereafter, the mechanical seal flushing water air vent valve 542a of the booster feed pump 51 is fully closed to fully closed. At this time, the air is completely closed after the air is exhausted. That is, while flushing water (cooling water) is circulated through the booster feed pump 51, the air is shut off. That is, a standby state for restoring the shaft cooling system of the booster feed pump 51 is secured.

  Next, the seal water connection pipe blow valve 531a of the boiler feed pump 52 is confirmed to be fully opened, and the seal water connection pipe blow valve front valve 531b of the boiler feed pump 52 is confirmed to be fully opened. That is, a flow path for returning the sealed water supplied to the boiler feed water pump 52 to the condenser 40 is secured. On the other hand, after removing the blow hose 502 from the detection pipe 5010 for the rotor balance pipe pressure gauge, the detection pipe original valve 5010a for the rotor balance pipe pressure gauge is kept fully open to balance the rotation of the rotor of the boiler feed pump 52. Be able to hold. And it confirms that the casing blow valve 5215a of the boiler feed pump 52 is fully closed, and ensures the standby state of the recovery of the boiler feed pump 52.

  Next, the casing blow valve 5113a of the booster water supply pump 51 is fully closed from the fully open state, and the strainer blow valve 5111a of the booster water supply pump 51 is fully closed. That is, a standby state for restoring the booster feed pump 51 is secured.

  Then, the overheat prevention pipe drain valve 5212b of the boiler feed water pump 52 is fully closed and the outlet pipe drain valve 5211a of the boiler feed pump 52 is fully closed to ensure the standby state of the recovery of the water system of the boiler feed pump 52. To do.

  Next, the casing air vent valve 5112a of the booster feed pump 51 is operated to be adjusted open, and the strainer air vent valve 5110a of the booster feed pump 51 is operated to be adjusted open.

  Next, the casing air vent valve 5214a of the boiler feed water pump 52 is operated to be adjusted open, and the outlet air vent valve 5210a of the boiler feed water pump 52 is operated to be adjusted open.

Next, the seal water minimum flow rate adjustment valve (coupling side) 530b of the boiler feed water pump 52 is fully opened, and the seal water minimum flow rate adjustment valve (counter coupling side) 530b of the boiler feed pump 52 is fully opened. That is, sealing water is supplied to the shaft portion of the boiler feed pump 52 (shaft seal).

  Next, the casing air vent valve 5214a of the boiler feed pump 52 is fully closed. On the other hand, the casing air vent valve 5112a of the booster feed pump 51 is fully closed, and the strainer air vent valve 5110a of the booster feed pump 51 is fully closed to fully close the outlet air vent valve 5210a of the boiler feed pump 52. At the same time, the minimum sealing water flow rate adjustment valve (coupling side) 530b of the boiler feed pump 52 is adjusted to open, and the minimum sealed flow rate adjustment valve (anti-coupling side) 530b of the boiler feed pump 52 is adjusted to open. To do.

  Thereafter, the overheat prevention valve front valve 5212a of the boiler feed water pump 52 is fully opened. On the other hand, the E lock of the inlet valve 511a of the boiler feed pump 52 is released (not shown). The central operation is performed while the inlet valve 511a of the boiler feed pump 52 is adjusted open. At this time, pay attention to the water hammer. And the outlet valve front air vent valve 5210a of the boiler feed pump 52 is operated from closing to opening. Vent air from the water supply line.

  Next, the instrument is vented. First, the central operation is performed so that the inlet valve 511a of the booster feed pump 51 is fully opened, and the warming valve 5213a of the boiler feed pump 52 is fully opened. At this time, when opening the warming valve 5213a, the opening operation is gradually performed while confirming the temperature rise of the boiler feed pump 52.

  The E lock of the outlet valve 521a of the boiler feed pump 52 is released. That is, the electromagnetic switch (not shown) is closed, and the E lock of the booster feed pump 51 is released (not shown). That is, the circuit breaker is connected to the power supply circuit (not shown), and the wiring circuit breaker is turned on (not shown). That is, trial operation of the booster feed pump 51 and the boiler feed pump 52 is started. In this case, since the sealing water is full in the boiler feed pump 52, the recovery time is shortened.

  As described above, the isolation method at the time of maintenance in the power generation facility according to the present embodiment is such that only the water system of the boiler feed pump 52 is isolated so that water flows from the boiler feed pump 52 to the booster feed pump 51 side. In this way, the booster feed pump 51 can be repaired. And since there is no isolation of the steam system of the boiler feed pump 52, the burden on the operator is reduced as much as monitoring of the vacuum reduction of the condenser 40 is eliminated. Since there is no isolation between the steam system and the water system as in the prior art, the time required for the operation of opening and closing each valve in the wide range from the boiler feed pump 52 to the booster feed pump 51 is greatly reduced. Further, at the time of restoration, it is only necessary to restore the water system of the boiler feed pump 52, that is, it is only necessary to operate each valve in the section where the outlet water and the inlet side of the boiler feed pump 52 are blocked. Furthermore, since the steam system of the boiler feed pump 52 is utilized, the vacuum value of the condenser 40 does not decrease. That is, there is no difference in the degree of vacuum between the condenser 40 and the exhaust chamber of the turbine T of the boiler feed pump 52, and the recovery time can be greatly shortened.

  In addition, the electric power generation equipment which concerns on this invention can be variously changed without limiting to the said embodiment.

  For example, in the case of the above-described embodiment, the present invention is applied to a thermal power generation facility, but needless to say, it can also be applied to a nuclear power generation facility having a steam turbine system.

DESCRIPTION OF SYMBOLS 10 ... Boiler, 40 ... Condenser, 50 ... Water supply means, 51 ... Booster feed pump, 52 ... Boiler feed pump, 500 ... Connection piping, 501 ... Rotor balance piping, 502 ... Blow hose, WLa ... Condensate system, WLb: Water supply system, WLc: Shaft seal water supply system, WLd: Shaft cooling system

Claims (5)

A condensate / water supply system (WLa, WLb) for supplying the boiler (10) with the condensate condensed by the condenser (40) after working the steam generated in the boiler (10); A shaft seal water supply system (WLc) that supplies a part of the shaft as seal water for the water supply means (50) disposed in the condensate / water supply system (WLa, WLb), the water supply means (50) A booster feed pump (51) and a boiler feed pump (52), and a connecting pipe (500) for connecting the outlet side of the booster feed pump (51) and the inlet side of the boiler feed pump (52) from above. In a power generation facility having
While turning the boiler feed pump (52) and steam sealing,
Next, while supplying the sealed water from the condenser (40) to the inside of the boiler feed pump (52), while blocking the flowing water from the exit side of the boiler feed pump (52), the boiler feed pump (52 ) To prevent running water from the entrance side,
Next, in the booster feed pump (51), after confirming that there is no running water from the boiler feed pump (52), maintenance of the booster feed pump (51) is performed. Isolation method of time.   2. The boiler feed pump (52) is filled with sealed water after blocking water flowing on the outlet side and the inlet side of the boiler feed pump (52). Isolation method for maintenance of power generation facilities in Japan.   3. The power generation according to claim 1, wherein after the flowing water on the outlet side and the inlet side of the boiler feed pump (52) is blocked, the casing of the boiler feed pump (52) is vented. Isolation method for maintenance in equipment.   The connection pipe (500) is connected to a rotor balance pipe (501) for maintaining the balance of the rotor of the boiler feed pump (52), and a blow hose (502) is connected to the rotor balance pipe (501). The boiler feed pump (52) is confirmed to be filled with sealed water by confirming the flowing water from the blow hose (502). The isolation method at the time of the maintenance in the power generation facility of any one of thru | or 3.   While the inside of the boiler feed pump (52) is kept filled with sealed water, the section for blocking the flowing water on the outlet side and the inlet side of the boiler feed pump (52) is blown, and then the booster feed pump ( The isolation method at the time of maintenance in the power generation facility according to any one of claims 1 to 4, wherein the maintenance of (51) is performed.

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