Exhaust steam cooling system of water feed pump turbine

Abstract

The utility model provides a water feed pump turbine exhaust steam cooling system which comprises a water feed pump turbine, a tee joint and a bypass mechanism, the water feed pump turbine comprises a steam exhaust hole, and the steam exhaust hole is connected with one end of a steam exhaust pipeline; the tee joint comprises an inlet and a first outlet, and the other end of the steam exhaust pipeline is communicated with the inlet of the tee joint; one end of the bypass mechanism is connected with the first outlet of the tee joint, and the other end of the bypass mechanism is connected with a main machine condenser, so that the feed pump turbine is directly connected to the main machine condenser, and exhaust steam of the feed pump turbine is directly cooled; a tee joint is installed on an original steam exhaust pipeline, steam exhaust of a water feeding pump turbine is directly connected to a main machine condenser through a bypass mechanism, the water feeding pump turbine is cooled, and a large amount of circulating cooling water of a mechanical ventilation wet type cooling tower is saved.

Description

Technical Field

[0001] This application belongs to the technical field of direct air-cooled unit cooling, and specifically relates to an exhaust steam cooling system for a feed water pump steam turbine. Background Art

[0002] The exhaust steam cooling system for a feed water pump steam turbine adopts a circulating cooling water system with a mechanical draft wet cooling tower. Usually, the exhaust steam of each unit's feed water pump steam turbine is an independent exhaust system. That is to say, the exhaust steam condensate of the feed water pump steam turbine is boosted by the condensate pump of the feed water pump steam turbine or the condensate water is discharged into the main condenser through the condensate water gravity flow valve. Since the exhaust steam cooling system of the feed water pump steam turbine adopts an open circulating cooling water system, a large amount of cooling water needs to be evaporated and lost every year. Summary of the Utility Model

[0003] Therefore, the technical problem to be solved by this application is to provide an exhaust steam cooling system for a feed water pump steam turbine to solve at least one of the above problems existing in the prior art.

[0004] To solve the above problems, this application provides an exhaust steam cooling system for a feed water pump steam turbine, including a feed water pump steam turbine, a three-way joint and a bypass mechanism. The feed water pump steam turbine includes an exhaust hole, and the exhaust hole is connected to one end of an exhaust pipe; the three-way joint includes an inlet and a first outlet, and the other end of the exhaust pipe is communicated with the inlet of the three-way joint; one end of the bypass mechanism is connected to the first outlet of the three-way joint, and the other end of the bypass mechanism is connected to the main condenser, so that the feed water pump steam turbine is directly connected to the main condenser to directly cool the exhaust steam of the feed water pump steam turbine.

[0005] Optionally, the bypass mechanism includes a bypass pipe. One end of the bypass pipe is connected to the first outlet of the three-way joint, and the other end is connected to the main condenser. A first valve is provided on the bypass pipe.

[0006] Optionally, the bypass mechanism further includes a branch pipe. The branch pipe is arranged in parallel with the first valve. Both ends of the branch pipe are communicated with the bypass pipe, and a second valve is provided on the branch pipe.

[0007] Optionally, the first valve adopts an electric isolating valve, and the second valve adopts a manual stop valve.

[0008] Optionally, the exhaust steam cooling system for the feed water pump steam turbine further includes a condenser for the feed water pump steam turbine. The three-way joint further includes a second outlet, and the condenser for the feed water pump steam turbine is communicated with the second outlet of the three-way joint.

[0009] Optionally, when the back pressure of the main condenser is not greater than 12 KPa, the first valve of the bypass mechanism is opened so that the exhaust steam of the feed water pump steam turbine is connected into the main condenser;

[0010] When the back pressure of the main condenser is greater than 12 KPa throughout the day, the first valve of the bypass mechanism is closed so that the exhaust steam of the feed water pump steam turbine is connected to the condenser of the feed water pump steam turbine.

[0011] Optionally, the feed water pump steam turbines are arranged in a one - used - one - standby manner, namely the first feed water pump steam turbine and the second feed water pump steam turbine.

[0012] Optionally, the condensers of the feed water pump steam turbines are arranged in a one - used - one - standby manner, namely the first condenser of the feed water pump steam turbine and the second condenser of the feed water pump steam turbine.

[0013] Optionally, the bypass mechanisms are arranged in a one - used - one - standby manner, namely the first bypass mechanism and the second bypass mechanism.

[0014] Optionally, the tee includes a first tee and a second tee. The exhaust hole of the first feed water pump steam turbine is connected to the inlet of the first tee. The first outlet and the second outlet of the first tee are respectively connected to the first bypass mechanism and the first condenser of the feed water pump steam turbine;

[0015] The exhaust hole of the second feed water pump steam turbine is connected to the inlet of the second tee. The first outlet and the second outlet of the second tee are respectively connected to the second bypass mechanism and the second condenser of the feed water pump steam turbine;

[0016] Both the first bypass mechanism and the second bypass mechanism are connected to the main condenser.

[0017] Beneficial effects

[0018] A feed water pump steam turbine exhaust cooling system provided by the present application installs a tee on the original exhaust pipe, directly connects the exhaust steam of the feed water pump steam turbine to the main condenser through a bypass mechanism to cool the feed water pump steam turbine, saving a large amount of circulating cooling water of the mechanical draft wet cooling tower. Description of the drawings

[0019] Figure 1 It is a schematic diagram of the feed water pump steam turbine exhaust cooling system according to the embodiment of the present application.

[0020] The reference numerals are shown as:

[0021] 101 - The first feed water pump steam turbine; 102 - The second feed water pump steam turbine;

[0022] 201 - First feed water pump steam turbine condenser; 202 - Second feed water pump steam turbine condenser;

[0023] 301 - Bypass pipeline; 302 - First valve body; 303 - Second valve body; 304 - Branch pipeline;

[0024] 6 - Main engine condenser. Detailed implementation manner

[0025] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0026] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, "a plurality" means two or more unless otherwise specifically defined.

[0027] In the present application, unless otherwise clearly specified and defined, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0028] The following describes the preferred embodiments of the present utility model with reference to the drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present utility model and are not used to limit the present utility model.

[0029] Combined with reference to Figure 1 As shown, according to an embodiment of the present application, a steam exhaust cooling system for a feed water pump steam turbine is provided, including:

[0030] A feed water pump steam turbine, the feed water pump steam turbine includes an exhaust hole, and the exhaust hole is connected to one end of an exhaust pipeline;

[0031] A three-way pipe, the three-way pipe includes an inlet and a first outlet, and the other end of the exhaust pipe is communicated with the inlet of the three-way pipe;

[0032] A bypass mechanism, one end of the bypass mechanism is connected to the first outlet of the three-way pipe, and the other end of the bypass mechanism is connected to the main condenser 4 of the host, so that the feed water pump steam turbine is directly connected to the main condenser 4 of the host to directly cool the exhaust steam of the feed water pump steam turbine.

[0033] Install a three-way pipe on the original exhaust pipe, connect the exhaust steam of the feed water pump steam turbine directly to the main condenser 4 through the bypass mechanism, cool the feed water pump steam turbine, and save a large amount of circulating cooling water for the mechanical draft wet cooling tower.

[0034] Taking the 2×300MW supercritical indirect cooling unit of Inner Mongolia Jingtai Power Generation Co., Ltd. as an example, it is obtained from the analysis of past operation data that from June to October every year, when the unit is generating electricity at full load, the back pressure of the main condenser 4 is greater than 12KPa, while in the remaining time periods, the back pressure of the main condenser 4 is not greater than 12KPa. Therefore, in the water-scarce areas in the north, thermal power plants retain the condenser of the feed water pump steam turbine and the mechanical draft tower according to the existing equipment on site, and minimize the water consumption of the unit by switching the exhaust steam mode of the feed water pump steam turbine in winter and summer. It saves the annual water consumption of the unit, improves the operation economy, saves the manpower equipment maintenance cost, and is convenient for operation.

[0035] There are two sources of makeup water for the circulating cooling water of the feed water pump steam turbine. One is the Yellow River water, which is used as the makeup water for the circulating water of the feed water pump steam turbine, and the other is the dewatered water.

[0036] The bypass mechanism includes a bypass pipe 301. One end of the bypass pipe 301 is connected to the first outlet of the three-way pipe, and the other end is connected to the main condenser 4 of the host. A first valve 302 is provided on the bypass pipe 301.

[0037] Among them, by opening or closing the first valve 302, the feed water pump steam turbine is connected or closed to the main condenser 4; thereby enabling the feed water pump steam turbine to be directly connected to the main condenser 4 for cooling. Greatly reduce the water consumption of the unit.

[0038] The bypass mechanism further includes a branch pipe 304. The branch pipe 304 is arranged in parallel with the first valve 302. Both ends of the branch pipe 304 are respectively communicated with the bypass pipe 301. A second valve 303 is provided on the branch pipe 304.

[0039] Among them, a large butterfly valve is provided on the main pipe of the unit, and a second valve 303 is provided on the branch pipe 304. That is to say, when the large butterfly valve is opened, by opening the second valve 303, the function of balancing the differential pressure before and after can be achieved.

[0040] The first valve 302 adopts an electric isolation valve, and the second valve 303 adopts a manual stop valve.

[0041] Among them, the first valve 302 adopts an electric isolating valve. That is to say, according to the specific working conditions, it is necessary to select to open or close the electric isolating valve multiple times, and it is not necessary for the operator to go to the site to open it, reducing the labor intensity of the operator.

[0042] Among them, the second valve 303 adopts a manual globe valve. Only when the large butterfly valve set on the main pipeline of the unit is opened will the second valve 303 be opened. Since it does not need to be switched frequently, a manual globe valve is selected.

[0043] The exhaust cooling system of the feed water pump steam turbine further includes a feed water pump steam turbine condenser. The three-way also includes a second outlet, and the feed water pump steam turbine condenser is connected to the second outlet of the three-way.

[0044] Among them, according to the specific working conditions, it is necessary to select whether to connect the feed water pump steam turbine to the feed water pump steam turbine condenser or to connect the feed water pump steam turbine to the main condenser 4 to cool the feed water pump steam turbine. Under the condition of ensuring the normal operation of the unit, by switching whether to connect the feed water pump steam turbine to the feed water pump steam turbine condenser or to connect the feed water pump steam turbine to the main condenser 4, the water consumption of the unit is greatly reduced and water resources are saved.

[0045] When the back pressure of the main condenser 4 is not greater than 12 KPa, the first valve 302 of the bypass mechanism is opened so that the exhaust of the feed water pump steam turbine is connected into the main condenser 4;

[0046] When the back pressure of the main condenser 4 is greater than 15 KPa throughout the day, the first valve 302 of the bypass mechanism is closed so that the exhaust of the feed water pump steam turbine is connected to the feed water pump steam turbine condenser.

[0047] Among them, by adding a three-way and a bypass mechanism, it is used to realize the switching of the feed water pump steam turbine under different back pressures of the main condenser 4, ensuring the safe and economic operation of the feed water pump steam turbine.

[0048] The feed water pump steam turbines are in a one - used - one - standby mode, namely the first feed water pump steam turbine 101 and the second feed water pump steam turbine 102.

[0049] Among them, by adopting the one - used - one - standby operation mode of the first feed water pump steam turbine 101 and the second feed water pump steam turbine 102, when the feed water pump steam turbine in one of the systems fails, it can be switched to the other system to ensure the smooth operation of the system without the need for shutdown maintenance.

[0050] The feed water pump steam turbine condensers are in a one - used - one - standby mode, namely the first feed water pump steam turbine condenser 201 and the second feed water pump steam turbine condenser 202.

[0051] Among them, by adopting the operation mode of one in use and one standby for the first feed pump steam turbine condenser 201 and the second feed pump steam turbine condenser 202, when a failure occurs in the feed pump steam turbine condenser in one of the systems, it can be switched to the other system to ensure the smooth operation of the system without the need for shutdown maintenance.

[0052] The bypass mechanism adopts the mode of one in use and one standby, namely the first bypass mechanism and the second bypass mechanism respectively.

[0053] Among them, by adopting the operation mode of one in use and one standby for the first bypass mechanism and the second bypass mechanism, when a failure occurs in the bypass mechanism in one of the systems, it can be switched to the other system to ensure the smooth operation of the system without the need for shutdown maintenance.

[0054] The three-way includes the first three-way and the second three-way. The exhaust hole of the first feed pump steam turbine 101 is connected to the inlet of the first three-way, and the first outlet and the second outlet of the first three-way are respectively connected to the first bypass mechanism and the first feed pump steam turbine condenser 201;

[0055] The exhaust hole of the second feed pump steam turbine 102 is connected to the inlet of the second three-way, and the first outlet and the second outlet of the second three-way are respectively connected to the second bypass mechanism and the second feed pump steam turbine condenser 202;

[0056] Both the first bypass mechanism and the second bypass mechanism are connected to the main condenser 4.

[0057] Among them, the first feed pump steam turbine 101, the first three-way, the first bypass mechanism, and the first feed pump steam turbine condenser 201 form a set of systems; the second feed pump steam turbine 102, the second three-way, the second bypass mechanism, and the second feed pump steam turbine condenser 202 form a set of systems; when a failure occurs in one of the systems, it can be switched to the other system to ensure the stable operation of the unit.

[0058] The specific implementation process is as follows:

[0059] When the ambient temperature drops and the back pressure of the main condenser 4 is not greater than 12 kPa, open the first valve 302 on the bypass pipeline 301 between the feed pump steam turbine and the main condenser 4, connect the exhaust of the feed pump steam turbine to the main condenser 4, stop the operation of all equipment in the original feed pump steam turbine circulating water system, small turbine vacuum system, and condensate water system, and adjust the back pressure of the main condenser 4 and carry out anti-freezing of the indirect cooling tower by adjusting the louvers of the main engine indirect cooling tower.

[0060] As the ambient temperature rises, when the back pressure of the main condenser 4 is greater than 12 KPa (that is, from the analysis of the operation data of previous units: from June to October every year, when the unit generates electricity at full load, the back pressure of the main condenser 4 will be greater than 12 KPa), in order to reduce the heat load of the main condenser 4, the first valve 302 on the bypass pipeline 301 between the feed water pump steam turbine and the main condenser 4 is closed, and the exhaust steam of the feed water pump steam turbine is directly discharged into the condenser of the feed water pump steam turbine to reduce the back pressure of the main condenser 4 and ensure that the unit can operate at full load. And start all the equipment of the original circulating water system, vacuum system and condensate system of the feed water pump steam turbine.

[0061] It is easy for those skilled in the art to understand that, on the premise of no conflict, the above advantageous ways can be freely combined and superimposed.

[0062] The above are only the preferred embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above is only the preferred implementation manner of the present application. It should be pointed out that for those of ordinary skill in the art in the technical field of the present application, several improvements and modifications can be made without departing from the technical principle of the present application, and these improvements and modifications should also be regarded as the protection scope of the present application.

Claims

1. A feedwater pump steam turbine exhaust cooling system, characterized in that, Comprising: A feed water pump steam turbine, the feed water pump steam turbine including an exhaust hole, the exhaust hole being connected to one end of an exhaust pipe; A three-way joint, the three-way joint including an inlet and a first outlet, the other end of the exhaust pipe being communicated with the inlet of the three-way joint; A bypass mechanism, one end of the bypass mechanism being connected to the first outlet of the three-way joint, the other end of the bypass mechanism being connected to a main condenser (4), so that the feed water pump steam turbine is directly connected to the main condenser (4) to directly cool the exhaust steam of the feed water pump steam turbine.

2. The steam exhaust cooling system of a feed water pump steam turbine according to claim 1, wherein The bypass mechanism includes a bypass pipe (301), one end of the bypass pipe (301) being connected to the first outlet of the three-way joint, the other end being connected to the main condenser (4), and a first valve (302) being provided on the bypass pipe (301).

3. The steam exhaust cooling system of a feedwater pump steam turbine according to claim 2, wherein The bypass mechanism further includes a branch pipe (304), the branch pipe (304) being arranged in parallel with the first valve (302), both ends of the branch pipe (304) being communicated with the bypass pipe (301), and a second valve (303) being provided on the branch pipe (304).

4. The exhaust steam cooling system of a feed water pump steam turbine according to claim 3, characterized in that, The first valve (302) is an electric isolation valve, and the second valve (303) is a manual stop valve.

5. A steam extraction cooling system for a boiler feed pump steam turbine according to claim 1, characterized in that, The exhaust steam cooling system of the feed water pump steam turbine further includes a feed water pump steam turbine condenser, the three-way joint further includes a second outlet, and the feed water pump steam turbine condenser is communicated with the second outlet of the three-way joint.

6. A feed water pump steam turbine exhaust steam cooling system according to claim 3, wherein When the back pressure of the main condenser (4) is not greater than 12 KPa, the first valve (302) of the bypass mechanism is opened so that the exhaust steam of the feed water pump steam turbine is connected into the main condenser (4); When the back pressure of the main condenser (4) is greater than 15 KPa throughout the day, the first valve (302) of the bypass mechanism is closed so that the exhaust steam of the feed water pump steam turbine is connected to the feed water pump steam turbine condenser.

7. The exhaust steam cooling system of a feed water pump steam turbine according to claim 5, characterized in that, The feed water pump steam turbines are in a one - used - one - standby mode, namely a first feed water pump steam turbine (101) and a second feed water pump steam turbine (102).

8. The exhaust steam cooling system of a feed water pump steam turbine according to claim 7, characterized in that, The feed water pump steam turbine condensers are in a one - used - one - standby mode, namely a first feed water pump steam turbine condenser (201) and a second feed water pump steam turbine condenser (202).

9. The exhaust steam cooling system of a feed water pump steam turbine according to claim 8, wherein, The bypass mechanisms are in a one - used - one - standby mode, namely a first bypass mechanism and a second bypass mechanism.

10. A steam exhaust cooling system for a feed water pump steam turbine according to claim 9, characterized in that, The three - way joint includes a first three - way joint and a second three - way joint. The exhaust hole of the first feed water pump steam turbine (101) is connected to the inlet of the first three - way joint, and the first outlet and the second outlet of the first three - way joint are respectively connected to the first bypass mechanism and the first feed water pump steam turbine condenser (201); The exhaust hole of the second feed water pump steam turbine (102) is connected to the inlet of the second three - way joint, and the first outlet and the second outlet of the second three - way joint are respectively connected to the second bypass mechanism and the second feed water pump steam turbine condenser (202); Both the first bypass mechanism and the second bypass mechanism are connected to the main condenser (4).

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