JP5489771B2 - Gas extraction system for steam turbine plant, gas extraction operation method and construction method of gas extraction system - Google Patents

Description

  The present invention relates to a gas extraction system, a gas extraction operation method, and a gas extraction system construction method for extracting non-condensable gas from a condenser of a steam turbine plant including a steam turbine and a condenser.

In a turbine plant equipped with a steam turbine such as a geothermal power generation facility, the exhaust steam exhausted from the steam turbine is introduced into a condenser, where it is directly contacted with cooling water for heat exchange to be condensed. The The natural steam supplied to the steam turbine or the saturated steam separated from the hot water is often mixed with non-condensable gas of about 10 ⁻² to 10 ⁻¹ % by weight. If this non-condensable gas stays in the condenser, the degree of vacuum is reduced and the performance of the condenser is greatly affected. Therefore, the non-condensable gas is extracted from the condenser by a gas extraction device. .

As this gas extraction apparatus, for example, an apparatus provided with a multistage steam ejector for discharging non-condensable gas from a condenser is known (for example, see Patent Document 1). Here, the steam and the non-condensable gas are sucked from the condenser by the first stage steam ejector and supplied to the intercooler. The intercooler separates condensed water and non-condensable gas, collects condensed water in a condenser, and the non-condensed gas is sucked by the second-stage steam ejector and guided to the aftercooler together with the steam. In this after cooler, the condensed water and the non-condensable gas are separated again, the condensed water is collected in the condenser, and the non-condensable gas is released to the atmosphere.
As another gas extraction device, the non-compressible gas of the condenser is sucked by a screw-type gas compressor, is bitten by a screw portion, is continuously compressed, and is discharged to the outside in an atmospheric pressure state. Such a configuration is known (for example, see Patent Document 2).

Japanese Patent No. 3638329 JP 60-56184 A

  However, in the conventional example described in Patent Document 1, steam ejectors are connected in multiple stages so as to suck the incompressible gas of the condenser. In the geothermal power generation system, a part of the steam supplied to the steam turbine is supplied to the steam ejector as driving steam, and the amount of steam supplied to the steam turbine is reduced by this amount. There is an unresolved issue of reduced efficiency.

  On the other hand, in the conventional example described in Patent Document 2, hot water generated from a geothermal well is separated into saturated steam and saturated water by a steam-water separator, and the saturated steam is converted into a steam turbine. By supplying and supplying saturated water to the screw-type hot water turbine to drive the hot water turbine, and driving the gas compressor that extracts the incompressible gas from the condenser with the power generated by this hot water turbine The saturated steam separated by the steam separator can be all supplied to the steam turbine, and there is an advantage that the efficiency of the steam turbine can be improved.

  However, even if the steam well is attenuated and only low-load operation can be performed, if the gas flow rate of the gas compressor is insufficient, surging may occur and the drive may be stopped. In order to maintain the gas flow rate, the discharge gas must be recirculated to the condenser to operate, the auxiliary power cannot be reduced, and it cannot be improved beyond the planned degree of vacuum. Although the gas compressor is highly efficient in the rated output state, in a part-load operation plant, even in high vacuum conditions where the cooling water temperature is low, such as in winter, the condenser is There is an unsolved problem that high vacuum operation is not possible.

  Therefore, the present invention has been made paying attention to the unsolved problems of the conventional example described above, and by using a steam ejector and a gas compressor together when extracting the non-condensable gas of the condenser. An object of the present invention is to provide a gas extraction system, a gas extraction operation method, and a gas extraction system construction method for a steam turbine plant that can maintain the high vacuum of the condenser and increase the output of the steam turbine.

To achieve the above object, a gas extraction system of the turbine plant according to one of the shape state is condensate to the condensate and steam turbine steam is supplied from the steam supply source, the steam discharged from the steam turbine A steam turbine plant gas extraction system for extracting a non-condensable gas from the condenser in a steam turbine plant comprising a condenser, wherein a gas extraction device for extracting the non-condensable gas is connected to the condenser. , 該Ga scan extraction apparatus and initial suction multistage steam ejector for exhausting by suction the condenser of the steam by the driving steam supplied from the steam supply source to the initial start of the steam turbine plant, the steam supply a normal suction steam ejector which sucks vapor containing non-condensable gases from the condenser by a driving steam supplied from being sucked in the normal suction steam ejector vapor And the intercooler but supplied, a mist eliminator for removing particles of the steam output from the intercooler, a gas compressor noncondensable gas separated by the mist eliminator is supplied, at the start of the steam turbine plant After the condenser vacuum is increased by the initial suction multistage steam ejector, the condenser is opened and the exhaust gas from the gas compressor is returned to the condenser, and is closed when the normal suction steam ejector is started. The first gas circulation path and the exhaust gas of the gas compressor are controlled to be opened after the gas compressor is started and water is supplied to the intercooler when the steam turbine plant is started. And at least a second gas circulation path for returning the exhaust gas of the machine to the intercooler .

A gas extraction operation method for a steam turbine plant according to an aspect of the present invention includes a steam turbine to which steam is supplied from a steam supply source, and a condenser for condensing steam discharged from the steam turbine. a gas extraction method of operating a steam turbine plant for extracting non-condensable gases from the condenser of the steam turbine plant, to connect the gas extraction device for extracting non-condensable gas into the condenser, 該Ga scan The extraction device includes an initial suction multi-stage steam ejector that sucks steam from the condenser by driving steam supplied from the steam supply source in the initial stage of startup of the steam turbine plant, and driving steam supplied from the steam supply source. A normal suction steam ejector for sucking steam containing non-condensable gas from the condenser; an intercooler to which the steam sucked by the normal suction steam ejector is supplied; and A mist eliminator for removing fine particles of steam output from an intercooler, a gas compressor to which a non-condensable gas separated by the mist eliminator is supplied, and a multistage steam ejector for initial suction when the steam turbine plant is started A first gas circulation path which is opened after the vacuum degree of the condenser is raised, returns exhaust gas from the gas compressor to the condenser, and is closed at the start of operation of the normal suction steam ejector. And when the steam turbine plant is started, the gas compressor is started and water is supplied to the intercooler, and then the exhaust gas is discharged from the gas compressor to the intercooler. And a second gas circulation path to be returned.

The gas extraction operation method for a steam turbine plant according to another aspect of the present invention controls the drive steam supply to the normal suction steam ejector at the start of the normal operation process with the drive steam valve, and opens the drive steam valve at an initial stage. degree increases up to a predetermined opening drive dynamic steam flow rate does not change at low growth rate, after reaching the predetermined degree of opening is characterized in that a fully open state by increasing the degree of opening in pressure ratio high multiplication.

  A construction method of a gas extraction system for a steam turbine plant according to an aspect of the present invention includes a steam turbine to which steam is supplied from a steam supply source, and a condenser for condensing steam discharged from the steam turbine. A steam turbine plant in which a steam ejector and an intercooler are newly installed between the condenser and the mist eliminator in a gas extraction system for extracting non-condensable gas from the condenser of the steam turbine plant equipped with the gas compressor through a mist eliminator A gas extraction system construction method in which a steam pipe connecting between the condenser and a mist eliminator disposed in the vicinity of the condenser is cut by a predetermined length, and A first external connection pipe is connected to the water tank side, a second external connection pipe is connected to the mist eliminator side of the cutting portion, and the first and second pipes are connected. When connecting the connecting pipe connecting the other end to the other end of the pipe for connecting the section to secure a steam passage between the condenser and the mist eliminator, and when the installation of the steam ejector and the intercooler is completed The communication pipe is removed, an inlet side pipe of a steam ejector is connected to the first external connection pipe, and an outlet side pipe of the intercooler is connected to the second external connection pipe.

According to the present invention, the gas extraction device of the condenser has a configuration in which the steam ejector and the gas compressor are used in combination, so that the amount of steam supplied to the steam turbine is reduced and the condenser of the gas compressor is reduced. When the vacuum level drops, the steam ejector sucks the steam containing the non-condensable gas of the condenser, thereby ensuring the condenser vacuum level and increasing the output of the steam turbine. It is done.
Further, according to the operation method of the present invention, when starting the steam ejector for the gas compressor that is greatly affected by the fluctuation of the gas discharge amount, it is started without changing the gas discharge amount of the gas compressor, The effect that the stable gas extraction from a condenser can be performed is acquired.
Furthermore, according to the construction method of the present invention, when a steam ejector and an intercooler are newly installed for a gas extraction apparatus using an existing gas compressor, there is an effect that the downtime of the steam plant can be shortened. can get.

It is a system distribution diagram showing one embodiment of the present invention. It is a time chart which shows the control state of each control valve at the time of starting. It is a time chart which shows the control state of each control valve at the time of an operation stop. It is a characteristic diagram which shows the opening degree control of an ejector drive steam valve. It is a system system figure which shows the state before and behind construction of a gas extraction system. It is a top view which shows the system configuration | structure of the construction state of a gas extraction system. It is a top view which shows the system configuration | structure after construction of a gas extraction system. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a system diagram showing an embodiment when the present invention is applied to a geothermal power generation system.
In FIG. 1, reference numeral 10 denotes a steam supply source. Although not shown, geothermal steam ejected from a production well excavated in the ground is separated into steam and hot water by a high-pressure separator, and the separated steam is output.
The steam output from the steam supply source 10 is supplied to the steam turbine 11 and converted into a rotational force to drive the generator 12 to rotate.

The steam discharged from the steam turbine 11 is supplied to a condenser 13 to condense and condense the steam, and the condensed water is pressurized by a pumping pump 14 and supplied to a chilled water tower (not shown) for cooling. Is done.
A gas extraction device 15 is connected to the upper side of the condenser 13. The gas extraction device 15 includes an initial suction multistage steam ejector 17, a normal suction steam ejector 32, an intercooler 34, a mist eliminator 37, and a gas compressor 41.

  A gas extraction port 13a is provided in the upper part of the condenser 13, and this gas extraction port 13a is connected to a multistage steam ejector 17 for initial suction through a gas pipe 16 having an ejector inlet valve MV1 interposed therebetween. In this initial suction multistage steam ejector 17, a part of the steam supplied from the steam supply source 10 is supplied as driving steam through the auxiliary steam inlet valve MV <b> 2, and sucks steam containing non-condensable gas in the condenser 13. The first steam ejector 18, the gas cooler 19 that is supplied with the steam including the non-condensable gas output from the first steam ejector 18, is cooled, and is supplied as driving steam through the auxiliary steam inlet valve MV 2. And a second steam ejector 20 that sucks the steam containing the non-condensable gas cooled in 19. The noncondensable gas sucked by the second steam ejector 20 is supplied to a cooling tower (not shown) through the gas pipe 21.

  A branch pipe 31 having a compressor inlet valve MV3 is disposed on the condenser 13 side of the ejector inlet valve MV1 of the gas pipe 16, and this branch pipe 31 is connected to the suction port 32a of the normal suction steam ejector 32. It is connected. The normal suction steam ejector 32 is supplied with driving steam through a branch pipe 33 connected to the steam supply source 10 side of the auxiliary steam inlet valve MV2, and contains the non-condensable gas of the condenser 13 by this driving steam. Aspirate vapor. In the branch pipe 33, an ejector-driven steam source valve V1 and an ejector-driven steam valve MV4 are inserted.

  Then, the steam containing the non-condensable gas sucked by the normal suction steam ejector 32 is supplied to the intercooler 34 and cooled. The intercooler 34 is supplied with cooling water from a cooling water pump (not shown) via a cooling water pipe 35 having a cooling water inlet valve V2 inserted into the cooling water inlet 34a at the top, and a lower drain port 34b. A drain pipe 34f with a drain valve V3 interposed therebetween is connected to it. In addition, a second gas circulation pipe 44 (to be described later) inserted through a gas compressor minimum flow receiving valve V4 is connected to the gas circulation port 34c in the intermediate portion of the intercooler 34.

  A gas discharge port 34d at the upper part of the intercooler 34 is connected to a mist eliminator 37 for removing particulates in the gas via a gas pipe 36. The non-condensed gas from which the fine particles have been removed by the mist eliminator 37 is supplied to the two-stage gas compressor 41 via the gas pipe 38 and compressed. The gas compressor 41 includes two-stage screw compressors 41a and 41b, and these screw compressors 41a and 41b are connected to and driven by an electric motor 41d via a power transmission member 41c. The compressed gas output from the screw compressor 41a is cooled by the intercooler 41e and then input to the screw compressor 41b to be further compressed.

The compressed gas output from the screw compressor 41 b of the gas compressor 41 is supplied to the cooling tower through the gas discharge pipe 42, and part of the compressed gas is returned to the condenser 13 through the first gas circulation pipe 43. . In this first gas circulation pipe 43, a gas compressor circulation valve V7 is inserted in the vicinity of the gas circulation port 13b of the condenser 13.
Further, a second gas circulation pipe 44 is branched from between the gas compressor circulation valve V 7 and the gas discharge pipe 42 of the first gas circulation pipe 43, and this second gas circulation pipe 44 is connected to the gas circulation of the intercooler 34. It is connected to the mouth 34c. The flow rate of the non-condensable gas circulated in the first gas circulation pipe 43 is determined by the opening degrees of the electric valve MV5 and the bypass valve MV6 arranged in parallel near the gas discharge pipe 42. In addition, a compressor outlet valve MV7 is disposed at a connecting portion between the gas pipe 21 from the multistage steam ejector 17 and the gas discharge pipe 42 from the gas compressor 41.
Next, the operation method of the above embodiment will be described with reference to FIGS.

  First, in order to start the steam turbine plant, the drain line of the intercooler 34 inserted between the normal suction steam ejector 32 and the mist eliminator 37 is filled. This water filling causes the intercooler drain valve V3 to be fully closed, and then causes the original valves V5 and V6 of the level sensor 34e provided in the intercooler 34 to be fully open. At this time, it is confirmed that the level sensor 34e is not operating.

  Next, the intercooler cooling water inlet valve V2 is slightly opened, and water filling of the intercooler 34 is started. Thereby, when the water level of the intercooler 34 rises and the level sensor 34e is activated, the intercooler cooling water inlet valve V2 is fully closed. Next, the intercooler drain valve V3 is opened, and after the level sensor 34e returns to the non-operating state, the intercooler drain valve V3 is fully closed to complete the filling of the intercooler 34.

  Next, the valve open / closed state is confirmed before the vacuum of the condenser 13 is increased. This confirmation is made by checking that the ejector inlet valve MV1 is closed, the auxiliary steam inlet valve MV2 is closed, the compressor inlet valve MV3 is closed, the ejector drive steam valve MV4 is closed, the compressor outlet valve MV7 is closed, and the ejector is driven. The steam source valve V1 is open, the gas compressor minimum flow receiving valve V4 is closed, the intercooler cooling water inlet valve V2 is closed, the intercooler drain valve V3 is closed, and the gas compressor circulation valve V7 is closed. Make sure.

  Thereafter, the condenser 13 is started to be boosted to a vacuum. By opening the ejector inlet valve MV1 and opening the auxiliary steam inlet valve MV2, the multistage steam ejector 17 is activated, and the gas in the condenser 13 is supplied to the first steam ejector 18 and the second steam ejector 18. The steam ejector 20 is used to raise the vacuum degree of the condenser 13, and when the predetermined vacuum degree is reached, the steam turbine 11 is started to increase the load.

  After confirming that the degree of vacuum of the condenser 13 is stable, the gas compressor circulation valve V7 is fully opened, and the motorized valve MV5 is opened 25%. Next, as shown in FIG. 2, at the time t1, the compressor inlet valve MV3 is opened, and the compressor outlet valve MV7 is opened. Next, the bypass valve MV6 is opened at a time t2 delayed from the time t1, and the opening of the ejector inlet valve MV1 is shifted to a closed state at a relatively high speed at a time t3 delayed by a predetermined time from the time t2. The electric motor 41d of the compressor 41 is driven to start the gas compressor 41.

At time t4 when the ejector inlet valve MV1 is fully closed, the opening degree of the auxiliary steam inlet valve MV2 is shifted to the closed state at a relatively high speed.
Thereafter, the flow of the cooling water to the intercooler 34 is started at time t5. In order to start water flow to the intercooler 34, first, the intercooler drain valve V3 is gradually opened to be fully opened. At this time, it is confirmed that there is no abnormality after the valve operating process and full opening of the intercooler drain valve V3.

  Next, the intercooler cooling water inlet valve V2 is gradually opened, and is fully opened after the water flow is confirmed. Also at this time, it is confirmed that there is no abnormality after the valve operation process of the intercooler cooling water inlet valve V2 and fully open. After fully opening the intercooler drain valve V3 and the intercooler cooling water inlet valve V2, it is confirmed that no problem has occurred in each device, and the water flow start processing of the intercooler 34 is terminated.

  Thereafter, the operation of the normal suction steam ejector 32 is started. At this time, first, it is confirmed that the gas compressor 41 is in a normal operation state. Next, the gas compressor minimum flow receiving valve V4 is gradually opened and fully opened so that the discharge flow rate of the gas compressor 41 does not fluctuate. In this state, the compressed gas compressed by the gas compressor 41 is gas discharge pipe 42, bypass valve MV6, first circulation pipe 43, second circulation pipe 44, intercooler 34, gas pipe 36 and mist eliminator 37, gas. A circulation path returning to the gas compressor 41 through the pipe 38 is formed. For this reason, driving is continued in a state in which the discharge flow rate fluctuation of the gas compressor 41 hardly occurs.

Next, the gas compressor circulation valve V7 is gradually closed so as not to fluctuate the discharge flow rate of the gas compressor 41, and is fully closed. It is confirmed that the gas compressor 41 is in a normal operation state when the gas compressor circulation valve V7 is fully closed.
Subsequently, the ejector drive steam valve MV4 is automatically controlled to be fully opened. In the automatic control of the ejector-driven steam valve MV4, as shown in FIG. 4, at the initial stage, a characteristic line L1 for gradually increasing the opening degree θ with time from the fully closed state is set. Reaches a predetermined opening θs (for example, 15%) at which the change in the steam flow rate (pressure) hardly occurs, the opening increase is continued at the characteristic line L2 having a larger gradient than the characteristic line L1, and the state is shifted to the fully open state.

  As described above, in the initial state, the opening is increased by the characteristic line L1 having a gentle gradient, and when the opening θ is equal to or larger than the predetermined opening θs, the opening is increased by the characteristic line L2 having a steep gradient. It is possible to start the normal suction steam ejector 32 without greatly changing the internal pressure of the water heater 13, to suppress the discharge pressure fluctuation of the gas compressor 41, and to generate surging in the gas compressor 41. Can be reliably prevented.

  Incidentally, when an experiment was performed to increase the opening θ of the ejector-driven steam valve MV4 with a gradient that is, for example, about twice as large as the gradient of the characteristic line L1, the internal pressure of the condenser 13 is large when performing the open side control. Although it does not fluctuate, when close side control is performed with the same gradient, the internal pressure of the condenser 13 fluctuates greatly (decrease in vacuum), fluctuates to the alarm level, and surging occurs in the gas compressor 41 The possibility of stopping was increased.

Therefore, by automatically controlling the opening degree of the ejector-driven steam valve MV4 using the characteristic lines L1 and L2, the internal pressure of the condenser 13 is increased both when the normal suction steam ejector 32 is started and when the operation is finished. It is possible to reliably prevent the fluctuation.
On the other hand, when stopping the steam turbine plant, as shown in FIG. 3, at time t11, the gas compressor 41 is stopped and the bypass valve MV6 is shifted from the open state to the fully closed state with a relatively steep slope. . At the same time, the auxiliary steam inlet valve MV2 is gradually opened to be fully opened.

Next, at time t12, the ejector inlet valve MV1 is gradually opened to be fully opened. Thereby, it will be in the state similar to the initial state where the vapor | steam containing the non-condensable gas of the condenser 13 is attracted | sucked by the multistage steam ejector 17. FIG.
Next, at time t13, the compressor inlet valve MV3 is gradually closed to be fully closed, and the ejector drive steam valve MV4 is gradually closed to be fully closed. As a result, the normal suction steam ejector 32 is stopped.

  Subsequently, at time t14, the compressor outlet valve MV7 is gradually closed to be fully closed, and then the gas compressor 41 is stopped at time t15 delayed for a predetermined time. Next, the supply of the cooling water is stopped at time t16, and after that, the operation state of the multistage steam ejector 17 is continued for a while, then the auxiliary steam inlet valve MV2 and the ejector inlet valve MV1 are closed, and the operation of the multistage steam ejector 17 is stopped. .

  Thus, according to the above embodiment, a part of the steam of the steam supply source 10 is consumed by the normal suction steam ejector 32, but the steam containing the non-condensable gas of the condenser 13 is one stage. Of the condenser 13 is cooled by the intercooler 34, removed by the mist eliminator 37 and then compressed by the gas compressor 41, thereby increasing the internal pressure of the condenser 13 to a high vacuum level. For example, the output of the steam turbine 11 can be increased by 10% as compared with the case where the output is sucked only by the gas compressor 41.

  Moreover, in order to increase the vacuum degree of the internal pressure of the condenser 13, either the multistage steam ejector with good operability or the high efficiency gas compressor is applied, as described in the conventional example. However, if efficiency is emphasized, a gas compressor is generally adopted. However, in order to operate this gas compressor with high efficiency, it is necessary to keep the internal pressure of the condenser 13 stable at a high degree of vacuum. For this reason, the amount of steam supplied from the steam supply source 10 is reduced. In this case, since the gas circulation amount through the first circulation path 43 of the gas compressor 41 is increased, the internal pressure of the condenser 13 is lowered and the efficiency is lowered. The gas compressor 41 can be operated with high efficiency by compensating for the decrease in the internal pressure by the normal suction steam ejector 32, and the efficiency of the entire gas extraction system can be increased. Can be increased.

Next, a gas extraction system construction method for constructing the above-described steam turbine system using an existing steam turbine system will be described.
In the existing steam turbine system in this case, as shown in FIG. 5, the branch pipe 31 is directly connected to the mist eliminator 37, and the steam containing the non-condensable gas in the condenser 13 is removed by the mist eliminator 37. After that, the gas compressor 41 is supplied. According to this configuration, since the steam including the non-condensable gas is sucked from the condenser 13 by the gas compressor 41, the steam supply source is compared with the case where the gas extraction system configured by the multistage steam ejector is configured. The steam containing the non-condensed gas can be sucked from the condenser 13 with high efficiency without consuming the steam supplied from 10.

  However, when the gas flow rate also decreases as the flow rate of the steam ejected from the production well constituting the steam supply source 10 decreases in a state where the performance of the gas compressor 41 is not deteriorated, the gas compression is performed as described above. In order to prevent surging of the machine 41, it is necessary to recirculate the discharge gas discharged from the gas compressor 41 to the condenser 13 so as to maintain the gas flow rate. At this time, due to the characteristic of the gas compressor that must maintain the minimum gas flow rate, the gas flow rate is reduced, but a high vacuum cannot be obtained in the turbine exhaust. For this reason, the output of the steam turbine 11 is lowered and the power generation efficiency is lowered.

For this reason, as in the embodiment described above, the internal suction steam ejector 32 and the intercooler 34 are inserted between the condenser 13 and the mist eliminator 37 so that the internal pressure of the condenser 13 is in a high vacuum state. The output of the steam turbine 11 can be increased.
For this purpose, it is necessary to newly install and connect a normal suction steam ejector 32 and an intercooler 34 to an existing steam turbine plant. In this case, in the system diagram of FIG. 5, with the normal suction steam ejector 32 and the intercooler 34 newly installed, the intermediate portion 31a of the branch pipe 31 connected to the mist eliminator 37 is cut off, and the ejector inlet of the branch pipe 31 is removed. The valve MV1 side is connected to the normal suction steam ejector 32, and the mist eliminator 37 side of the branch pipe 31 is connected to the gas pipe 36 connected to the intercooler 34.

However, the steam turbine plant must be stopped for a long time in order to connect the newly installed steam ejector 32 and the intercooler 34 for normal suction and the cut portion of the branch pipe 31, and geothermal power generation cannot be performed during this period. Loss occurs.
For this reason, in this invention, in order to shorten the stop period of a steam turbine plant, first, as shown in FIG.6 and FIG.9, the cutting | disconnection assumption position of the branch piping 31 which connects the condenser 13 and the mist eliminator 37 first. The first external connection pipe 51 connected to the cutting section on the condenser 13 side and the second external connection connected to the cutting section on the mist eliminator 37 side (the steam input port 37a of the mist eliminator 37 in this embodiment). A connecting member 54 including a connection pipe 52 and a U-shaped communication pipe 53 connected to the other ends of the first and second external connection pipes 51 and 52 is manufactured. Here, the other ends of the first and second external connection pipes 51 and 52 are connected to the cutting part of the branch pipe 31 and are parallel to each other at a predetermined distance and further the same at the same height position. It is formed so as to be positioned on a vertical plane. Further, connecting flanges 55 are formed at both ends of the first and second external connection pipes 51 and 52, respectively, and similarly, connecting flanges 56 are formed at both ends of the communication pipe 53.

  Then, in a state where the steam turbine plant is stopped, the branch pipe 31 is cut, a connecting flange 57 is welded to the cut portion, and the first external connecting pipe 51 of the connecting member 54 is connected to the connecting flange 57. At the same time, the second external connection pipe 52 of the connecting member 54 is connected to the steam input port 34 g of the mist eliminator 37. The connecting member 54 can be mounted in a short time that does not take a day, and when the connecting member 54 is mounted, the connecting member 54 can be attached from the gas pipe 16 connected to the condenser 13 via the connecting member 54. Since the state where the branched branch pipe 31 and the mist eliminator 37 are directly connected is maintained, the operation of the steam turbine plant can be resumed.

  In this state, as shown in FIGS. 7 to 9, the normal suction steam ejector 32 and the intercooler 34 are installed on the side of the condenser 13, for example, for 1 to 2 months, and the pipe connection between them is made. Do. When the installation of the normal suction steam ejector 32 and the intercooler 34 is completed, the communication pipe 53 of the connecting member 54 is removed while the steam turbine plant is stopped again. Next, as shown in FIG. 7, the connection pipe 61 connected to the suction port 32 a of the normal suction steam ejector 32 is connected to the first external connection pipe 51, and the intercooler 34 is connected to the second external connection pipe 52. The connecting pipe 62 connected to the gas discharge port 34d is connected. As a result, a gas passage is formed from the condenser 13 to the normal suction steam ejector 32 through the gas pipe 16, the branch pipe 31, the first external connection pipe 51, and the connection pipe 61, and from the intercooler 34. A gas passage reaching the mist eliminator 37 is formed through the connection pipe 62 and the second external connection pipe 52. In this state, the steam turbine plant is started according to the procedure described above.

In this way, by connecting the normal suction steam ejector 32 and the intercooler 34 using the connecting member 54, the normal suction steam ejector 32 and the intercooler 34 are connected to an existing steam turbine plant in a short period of time. It is possible to shorten the downtime of the steam turbine plant and minimize the loss due to the stop of geothermal power generation.
Note that the attachment timing of the connecting member 54 to the branch pipe 31 is not limited to the above, and the connecting member 54 is connected to the branch pipe 31 until the installation of the normal suction steam ejector 32 and the intercooler 34 is completed. It should be installed.

Further, the position of the end portion connecting the communication pipe 53 of the first external connection pipe 51 and the second external connection pipe 52 is not limited to the above position, but by changing the shape of the communication pipe 53. Any position can be arranged at the end, and can be arbitrarily set according to the positions of the connection pipes 61 and 62 of the normal suction steam ejector 32 and the intercooler 34.
Moreover, in the said embodiment, although the case where this invention was applied to a geothermal power plant was demonstrated, it is not limited to this, It can apply to the steam turbine plant which uses a steam turbine and a condenser. .

  DESCRIPTION OF SYMBOLS 10 ... Steam supply source, 11 ... Steam turbine, 12 ... Generator, 13 ... Condenser, 16 ... Gas piping, 17 ... Multistage steam ejector for initial suction, 18, 20 ... Steam ejector, 32 ... Steam ejector for normal suction 34 ... Intercooler, 37 ... Mist eliminator, 41 ... Gas compressor, 43 ... First circulation pipe, 44 ... Second circulation pipe, 51 ... First external connection pipe, 52 ... Second external connection Piping 53 ... Communication piping 54 ... Connection member 61,62 ... Connection piping

Claims (4)

A steam turbine for extracting non-condensable gas from the condenser in a steam turbine plant comprising a steam turbine to which steam is supplied from a steam supply source and a condenser for condensing steam discharged from the steam turbine A gas extraction system for a plant,
Connecting a gas extraction device for extracting non-condensable gas to the condenser;
該Ga to extract device,
A multistage steam ejector for initial suction for sucking and exhausting steam of the condenser by driving steam supplied from the steam supply source in the initial stage of startup of the steam turbine plant;
A normal suction steam ejector for sucking steam containing non-condensable gas from the condenser by driving steam supplied from the steam supply source;
An intercooler to which steam sucked by the normal suction steam ejector is supplied ;
A mist eliminator that removes vapor particulates output from the intercooler;
A gas compressor to which the non-condensable gas separated by the mist eliminator is supplied;
When starting up the steam turbine plant, the initial suction multistage steam ejector is opened after the vacuum level of the condenser is increased, and the exhaust gas of the gas compressor is returned to the condenser, and the normal suction steam ejector A first gas circuit that is closed at the start of operation of
When the steam turbine plant is started up, the gas compressor is started and water is supplied to the intercooler, and then the exhaust gas of the gas compressor is controlled to be opened to return the exhaust gas of the gas compressor to the intercooler. A gas extraction system for a steam turbine plant, comprising at least two gas circulation paths . A steam turbine for extracting noncondensable gas from the condenser of a steam turbine plant comprising a steam turbine to which steam is supplied from a steam supply source and a condenser for condensing steam discharged from the steam turbine A gas extraction operation method for a plant,
Connect the gas extraction device for extracting non-condensable gas into the condenser, 該Ga scan extraction device, the condenser of the steam by the driving steam supplied from the steam supply source to the initial start of the steam turbine plant A multi-stage steam ejector for initial suction for sucking in, a steam ejector for normal suction for sucking steam containing non-condensable gas from a condenser by driving steam supplied from the steam supply source, and a steam ejector for normal suction An intercooler to which the sucked steam is supplied, a mist eliminator for removing fine particles of steam output from the intercooler, a non-condensable gas separated by the mist eliminator, and an exhaust gas to the condenser And at least a gas compressor having first and second gas circulation paths individually returned to the intercooler,
When the steam turbine plant is started, first, the condenser gas is extracted by the multistage steam ejector for initial suction, and the first gas circulation path is opened after the vacuum degree of the condenser is increased. An initial startup process to start
A gas compressor starting step of starting the gas compressor after the vacuum degree of the condenser is stabilized;
An intercooler water flow start step for starting water flow to the intercooler;
A normal operation in which the second gas circulation path is fully opened while being gradually opened, and then the first circulation path is gradually closed to be fully closed, and then driving steam is supplied to the normal suction steam ejector to perform a normal operation. A gas extraction operation method for a steam turbine plant, comprising: a process. The normal the normal controls motive steam supply to the suction steam ejector with drive steam valve at the start of the operation process, a predetermined dynamic steam flow driving the opening of the driving steam valve at a low growth rate at the initial stage does not change the open increased to every said after a predetermined opening degree gas extraction method of operating a steam turbine plant according to claim 2, characterized in that a fully open state by increasing the degree of opening in pressure ratio high multiplication. A non-condensable gas is extracted from the condenser of the steam turbine plant having a steam turbine to which steam is supplied from a steam supply source and a condenser for condensing the steam discharged from the steam turbine by a gas compressor. A method for constructing a gas extraction system in a steam turbine plant in which a steam ejector and an intercooler are newly installed between the condenser and the mist eliminator in the gas extraction system for extracting via a mist eliminator,
A steam pipe connecting between the condenser and a mist eliminator disposed in the vicinity of the condenser is cut by a predetermined length,
Connecting the first external connection pipe to the condenser side of the cutting part, connecting the second external connection pipe to the mist eliminator side of the cutting part,
Connecting a communication pipe that communicates both to the other end of the first and second external connection pipes to secure a steam passage between the condenser and the mist eliminator;
When the installation of the steam ejector and the intercooler is completed, the communication pipe is removed, the inlet pipe of the steam ejector is connected to the first external connection pipe, and the intercooler is connected to the second external connection pipe. A method for constructing a gas extraction system in a steam gas turbine plan, characterized by connecting outlet piping.

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