CN219654752U - Steam turbine system - Google Patents

Steam turbine system Download PDF

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Publication number
CN219654752U
CN219654752U CN202320636099.9U CN202320636099U CN219654752U CN 219654752 U CN219654752 U CN 219654752U CN 202320636099 U CN202320636099 U CN 202320636099U CN 219654752 U CN219654752 U CN 219654752U
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China
Prior art keywords
pressure heater
steam
low
steam turbine
pressure
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CN202320636099.9U
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Chinese (zh)
Inventor
贺旭杰
谢天
尹俊杰
王一男
高兴
何宁
王文彬
刘明
严俊杰
高满达
王昕�
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Guodian Construction Investment Inner Mongolia Energy Co ltd
Xian Jiaotong University
National Energy Group New Energy Technology Research Institute Co Ltd
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Guodian Construction Investment Inner Mongolia Energy Co ltd
Xian Jiaotong University
National Energy Group New Energy Technology Research Institute Co Ltd
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Abstract

The utility model relates to the technical field of steam turbines and discloses a steam turbine system, which comprises a main steam turbine connected with a boiler (1), a hot well (7) connected with an outlet of the main steam turbine, a condenser (6) connected between the main steam turbine and the hot well (7) and a steam ejector (5) connected on the main steam turbine by-pass, wherein the hot well (7) is connected with the boiler (1) through condensation water and a water supply pipeline. Through the technical scheme, the steam ejector is connected to the main steam turbine, and when the short-term regulation operation load is reached under the power grid, the ejection quantity of the steam ejector can be changed, so that the steam flow of the main steam turbine is changed, and the flexible regulation and quick response of the output of the steam turbine are realized.

Description

Steam turbine system
Technical Field
The utility model relates to the technical field of steam turbines, in particular to a steam turbine system.
Background
Renewable energy sources such as solar energy and wind energy have strong time-varying characteristics, and large-scale photovoltaic and wind energy grid-connected power generation at present causes certain impact on a power grid, and is not beneficial to stable operation of the power grid. The thermal power generating unit needs to improve flexibility and economy, is suitable for the operation environment with frequent peak regulation, and can finish the load change process as soon as possible when a power grid instruction is issued.
When grid commands are issued, if the operation of the steam turbine is adjusted by adjusting the inlet amount of the main steam, unstable steam temperature can be caused, and even safety problems in the boiler can be caused, so that the required adjustment work can be more complicated.
At present, the patent with the application number of CN201711498480.9 discloses a variable-frequency power generation and backheating integrated feed pump turbine system, which comprises a main turbine, a small turbine, a second generator, a converter, a feed pump and a pre-steam pump, wherein the variable-load adjustment is realized by changing the feed water flow through the frequency conversion of the small turbine, but the change of the load adjustment system in this way has large delay and slower reaction.
Disclosure of Invention
The utility model aims to solve the problems of large delay and slow effect response of a load regulating system in the prior art, and provides a steam turbine system which is provided with a steam ejector and can regulate the output power of a unit more quickly.
In order to achieve the above purpose, the utility model provides a steam turbine system, which comprises a main steam turbine connected with a boiler, a hot well connected with an outlet of the main steam turbine, a condenser connected between the main steam turbine and the hot well, and a steam ejector connected on the main steam turbine, wherein the hot well is connected with the boiler through condensed water and a water supply pipeline.
Optionally, the main steam turbine includes the high-pressure cylinder, middling pressure jar and the low pressure jar that link to each other in proper order, the steam ejector bystander in on the middling pressure jar, the steam outlet of steam ejector with the hot well links to each other, the steam ejector with be equipped with a plurality of coolers between the hot well, a plurality of the cooler sets up on condensate water and the water supply pipeline.
Optionally, the device also comprises a backheating component arranged on the condensation water and water supply pipeline.
Optionally, the backheating assembly comprises a low pressure heater group connected with low pressure steam in the main turbine and a high pressure heater group connected with high pressure steam in the main turbine.
Optionally, the low pressure heater group includes first low pressure heater, second low pressure heater and the third low pressure heater that link to each other step by step, the high pressure heater group includes first high pressure heater, second high pressure heater and the third high pressure heater that link to each other step by step, the entry of first low pressure heater pass through first pressure piece with the hot well links to each other, the export of low pressure heater with the entry of first high pressure heater links to each other, the export of third high pressure heater with the boiler links to each other.
Optionally, the number of the coolers is three, and the three coolers are respectively arranged between the first low-pressure heater and the second low-pressure heater, between the second low-pressure heater and the third low-pressure heater, and between the third low-pressure heater and the first high-pressure heater.
Optionally, the first low-pressure heater and the second low-pressure heater are respectively connected with the end section and the middle section of the low-pressure cylinder in a bypass mode, the third low-pressure heater is connected with the end section of the medium-pressure cylinder in a bypass mode, the first high-pressure heater is connected with the head section of the medium-pressure cylinder in a bypass mode, and the second high-pressure heater and the third high-pressure heater are connected with the end section and the middle section of the high-pressure cylinder in a bypass mode respectively.
Optionally, a deaerator is also included that is disposed between the third low pressure heater and the first high pressure heater.
Optionally, the deaerator further comprises a second pressurizing piece arranged between the deaerator and the first high-pressure heater, and a driving piece is arranged on the second pressurizing piece.
Optionally, the high-pressure steam flows through the third high-pressure heater, the second high-pressure heater and the first high-pressure heater step by step and then flows into the deaerator, and the low-pressure steam flows through the third low-pressure heater, the second low-pressure heater and the first low-pressure heater step by step and then flows into the thermal well.
Through the technical scheme, the steam ejector is connected to the main steam turbine, and when the short-term regulation operation load is reached under the power grid, the ejection quantity of the steam ejector can be changed, so that the steam flow of the main steam turbine is changed, and the flexible regulation and quick response of the output of the steam turbine are realized.
Drawings
FIG. 1 is a schematic structural view of one embodiment of a steam turbine system in accordance with the present utility model.
Description of the reference numerals
1. The boiler, 2, the high pressure cylinder, 3, the medium pressure cylinder, 4, the low pressure cylinder, 5, the steam ejector, 6, the condenser, 7, the hot well, 8, the first pressure piece, 9, the first low pressure heater, 10, the second low pressure heater, 11, the third low pressure heater, 12, the deaerator, 13, the driving piece, 14, the second pressure piece, 15, the first high pressure heater, 16, the second high pressure heater, 17, the third high pressure heater, a, the main steam pipeline, b reheat steam pipeline.
Detailed Description
The following describes specific embodiments of the present utility model in detail with reference to the drawings. It should be understood that the detailed description and specific examples, while indicating and illustrating the utility model, are not intended to limit the utility model.
The utility model discloses a steam turbine system, which comprises a main steam turbine connected with a boiler 1, a thermal well 7 connected with an outlet of the main steam turbine, a condenser 6 connected between the main steam turbine and the thermal well 7, and a steam ejector 5 connected on the main steam turbine by-pass, wherein the thermal well 7 is connected with the boiler 1 through condensate water and a water supply pipeline.
As shown in fig. 1, the steam in the boiler 1 enters the main turbine to apply work, the steam after doing work is condensed into water through the condenser 6 and is collected into the hot well 7, the condensed water is conveyed to the combustion steam in the boiler to apply work and generate power in a circulating way, and a steam ejector 5 is connected to the main turbine, so that when the short-term regulation operation load is reached under the power grid, the ejection amount of the steam ejector 5 can be changed, the steam flow rate of the main turbine is changed, and the flexible regulation and quick response of the output force of the turbine are realized.
Further, the main steam turbine comprises a high-pressure cylinder 2, a medium-pressure cylinder 3 and a low-pressure cylinder 4 which are sequentially connected, a steam ejector 5 is connected to the medium-pressure cylinder 3, a steam outlet of the steam ejector 5 is connected with a hot well 7, a plurality of coolers are arranged between the steam ejector 5 and the hot well 7, and the coolers are arranged on condensate water and a water supply pipeline.
As shown in fig. 1, a steam inlet of a high-pressure cylinder 2 is connected with a main steam pipeline a of a boiler 1, a steam outlet of the high-pressure cylinder 2 is connected with an inlet of a reheat steam pipeline b of the boiler 1, a steam inlet of a medium-pressure cylinder 3 is connected with an outlet of the reheat steam pipeline b, a steam outlet of the medium-pressure cylinder is connected with a steam inlet of a low-pressure cylinder 4, a steam outlet of the low-pressure cylinder 4 is connected with a condenser 6, steam in the boiler 1 enters the high-pressure cylinder 2 through the main steam pipeline a, and after doing work, the steam in the high-pressure cylinder 2 returns to the boiler 1 through the reheat steam pipeline b to conduct non-contact heat transfer, so that the temperature of the steam in the reheat steam pipeline b rises, and then enters the medium-pressure cylinder 3, and the steam in the medium-pressure cylinder 3 continues to do work after doing work in the low-pressure cylinder 4; the steam ejected by the steam ejector 5 is converged with the condensed water in the hot well 7, meanwhile, the ejected steam can sequentially conduct non-contact heat transfer on the condensed water and the condensed water on the water supply pipeline through a plurality of coolers, energy cascade utilization is conducted, the temperature of the condensed water is continuously increased before the condensed water enters the boiler 1, the condensed water is preheated in advance, the working efficiency of the boiler 1 can be improved, and meanwhile, the ejected steam can be cooled and sent into the hot well 7 for recovery, so that higher economical efficiency is realized; in which the steam injector 5 is arranged on the medium pressure cylinder 3, for example on the high pressure cylinder 2, the higher the temperature of the steam in the high pressure cylinder 2, a large amount of available energy losses (also calledLoss), the range of the adjustment load becomes smaller if the hydraulic actuator is provided in the low-pressure cylinder 4.
The steam turbine system further comprises a heat regeneration assembly arranged on the condensed water and the water supply pipeline.
As shown in fig. 1, the condensed water is heated on the condensed water and the water supply pipeline through the heat recovery assembly, so that the condensed water can be effectively heated, the temperature of the condensed water is increased, the condensed water can be quickly evaporated into steam to continuously apply work after entering the boiler 1, the condensed water can reach a preset temperature before entering the boiler 1, and the working efficiency of the boiler 1 is greatly improved.
As an alternative embodiment, the recuperation assembly includes a low pressure heater group coupled to low pressure steam within the main turbine and a high pressure heater group coupled to high pressure steam within the main turbine.
As shown in fig. 1, the steam in the main steam turbine is divided into high-pressure steam and low-pressure steam, and part of the high-pressure steam is extracted into a high-pressure heater group and part of the low-pressure steam is extracted into a low-pressure heater group, the low-pressure heater group is used for primarily heating condensed water, the high-pressure heater group is used for further heating the condensed water, the high-pressure heater group and the low-pressure heater group are both self-flowing step by step in a drainage mode, namely, the drainage of the surface type heater utilizes the pressure difference between adjacent heaters, and the drainage is self-flowing step by step to the heater with lower pressure.
The low-pressure heater group comprises a first low-pressure heater 9, a second low-pressure heater 10 and a third low-pressure heater 11 which are connected step by step, the high-pressure heater group comprises a first high-pressure heater 15, a second high-pressure heater 16 and a third high-pressure heater 17 which are connected step by step, an inlet of the first low-pressure heater 9 is connected with the hot well 7 through a first pressure piece 8, an outlet of the low-pressure heater 11 is connected with an inlet of the first high-pressure heater 15, and an outlet of the third high-pressure heater 17 is connected with the boiler 1.
As shown in fig. 1, the number of the low-pressure heater groups and the high-pressure heater groups is three, so that condensed water in the thermal well 7 can be heated step by step, the condensed water in the thermal well 7 enters into the condensed water and the water supply pipeline through the first pressure piece 8, and the first pressure piece 8 is a water pump.
As an alternative embodiment, the number of coolers is three, and three coolers are respectively provided between the first low-pressure heater 9 and the second low-pressure heater 10, between the second low-pressure heater 10 and the third low-pressure heater 11, and between the third low-pressure heater 11 and the first high-pressure heater 15.
As shown in fig. 1, the first low-pressure heater 9, the second low-pressure heater 10 and the third low-pressure heater 11 are arranged along the flowing direction of the condensed water, so that the temperature of the first low-pressure heater 9 is lowest, the temperature of the third low-pressure heater 11 is highest, the three coolers comprise a cooler a, a cooler B and a cooler C, the temperature of steam in the cooler a is highest, the temperature of steam in the cooler C is lowest, the temperature of the injected steam is continuously reduced after passing through the three coolers, and the temperature of the condensed water is continuously increased after passing through the three coolers, so that the energy cascade utilization is realized.
Further, the first low-pressure heater 9 and the second low-pressure heater 10 are respectively connected with the tail section and the middle section of the low-pressure cylinder 4 in a bypass mode, the third low-pressure heater 11 is connected with the tail section of the medium-pressure cylinder 3 in a bypass mode, the first high-pressure heater 15 is connected with the head section of the medium-pressure cylinder 3 in a bypass mode, and the second high-pressure heater 16 and the third high-pressure heater 17 are respectively connected with the tail section and the middle section of the high-pressure cylinder 2 in a bypass mode.
As shown in fig. 1, after the high-pressure steam enters the high-pressure cylinder 2, the temperature of the steam is continuously reduced by continuously doing work, the pressure is also reduced along with the continuous reduction, the steam in the middle sections of the high-pressure cylinder 2 and the middle-pressure cylinder 3 is high-pressure steam, and the steam in the tail sections of the middle-pressure cylinder 3 and the low-pressure cylinder 4 is low-pressure steam; wherein, two pipelines are arranged in the heater and the cooler, and the steam pipeline and the condensed water pipeline are in non-contact heat transfer, so that the effects of condensed water heating and steam cooling are achieved.
In some embodiments, the turbine system further includes a deaerator 12 disposed between the third low pressure heater 11 and the first high pressure heater 15.
As shown in fig. 1, the deaerator 12 can deaerate condensed water in condensate water and water supply pipes, which include condensate pipes between the deaerator 12 and the hot well 7 and water supply pipes between the deaerator 12 and the boiler 1, and can prevent oxidation corrosion of pipe equipment and the like.
The steam turbine system further comprises a driving piece 13 arranged between the deaerator 12 and the first high-pressure heater 15, and a second pressurizing piece 14 is arranged on the driving piece 13.
As shown in fig. 1, the driving piece 13 can pump water in the deaerator 12 into the water supply pipe, the driving piece 13 is a water pump, the second pressing piece 14 can provide power for the driving piece 13, the second pressing piece 14 is a small turbine, steam of the small turbine is derived from partial steam in the medium pressure cylinder, and the small turbine provides a power source for the driving piece 13 through acting; and the steam injection quantity is changed, and simultaneously the steam inlet quantity of the small steam turbine can be synchronously changed, the water supply flow is adjusted, and the completion of the load changing process is accelerated. For example, when a load command is received and the unit is required to run under a load, the steam quantity of the cylinder is reduced, that is, a part of steam is led out from the steam ejector, after the steam is ejected, the whole steam quantity of the medium-pressure cylinder 3 is reduced, and the extraction steam used by the small steam turbine is reduced.
In some embodiments, the high pressure steam flows through the third high pressure heater 17, the second high pressure heater 16 and the first high pressure heater 16 in steps and then flows into the deaerator 12, and the low pressure steam flows through the third low pressure heater 11, the second low pressure heater 10 and the first low pressure heater 9 in steps and then flows into the thermal well 7.
As shown in fig. 1, the low-pressure steam carries out non-contact heat transfer on the water in the condensation water pipe step by step through the low-pressure heater group, and then flows into the thermal well 7 and merges with the condensed water; the high-pressure steam flows into the deaerator 12 after non-contact heat transfer with water in the water supply pipe through the high-pressure heater group and is combined with condensed water for deaeration, and the condensed water in the deaerator 12 flows into the boiler 1 after being heated through the cooler A and the high-pressure heater group.
The overall workflow of the turbine system:
the steam in the boiler 1 enters the high-pressure cylinder 2 through the main steam pipeline a to do work, wherein a small part of the steam enters the third high-pressure heater 17 and the second high-pressure heater 16, the steam after doing work enters the boiler 1 through the reheat steam pipeline b to be heated again and then enters the medium-pressure cylinder 3 to do work, a part of the steam enters the second pressurizing part 14 to do work and the third low-pressure heater 11 to do work, the steam after doing work enters the low-pressure cylinder 4 to do work, a small part of the steam enters the second low-pressure heater 10 and the first low-pressure heater 9 respectively, the steam after doing work enters the condenser 6 to be condensed into water and is collected into the hot well 7, the steam in the hot well 7 is heated through the low-pressure heater group, the high-pressure heater group and the cooler group respectively, and flows into the boiler 1 after heating is completed, and thus the cycle is realized; when the power grid gives an instruction, the work load in the main turbine can be quickly adjusted by adjusting the steam injection quantity of the steam injector 5, so that the steam flow rate of the turbine is changed, and the quick adjustment of the output of the turbine is realized. The steam injection quantity is changed, the steam inlet quantity of the small steam turbine of the feed pump can be synchronously changed, the feed water flow is adjusted, and the completion of the load changing process is accelerated.
The preferred embodiments of the present utility model have been described in detail above with reference to the accompanying drawings, but the present utility model is not limited thereto. Within the scope of the technical idea of the utility model, a number of simple variants of the technical solution of the utility model are possible, which simple variants and combinations should likewise be regarded as being disclosed by the utility model, all falling within the scope of protection of the utility model.
In addition, the specific features described in the above embodiments may be combined in any suitable manner without contradiction. The various possible combinations of the utility model are not described in detail in order to avoid unnecessary repetition.
Moreover, any combination of the various embodiments of the utility model can be made without departing from the spirit of the utility model, which should also be considered as disclosed herein.

Claims (10)

1. The steam turbine system is characterized by comprising a main steam turbine connected with a boiler (1), a hot well (7) connected with an outlet of the main steam turbine, a condenser (6) connected between the main steam turbine and the hot well (7) and a steam ejector (5) connected on the main steam turbine, wherein the hot well (7) is connected with the boiler (1) through condensation water and a water supply pipeline.
2. The steam turbine system of claim 1, wherein the main steam turbine comprises a high pressure cylinder (2), a medium pressure cylinder (3) and a low pressure cylinder (4) which are sequentially connected, the steam ejector (5) is connected to the medium pressure cylinder (3) by a side, a steam outlet of the steam ejector (5) is connected with the hot well (7), a plurality of coolers are arranged between the steam ejector (5) and the hot well (7), and the coolers are arranged on the condensate water and water supply pipeline.
3. The steam turbine system of claim 2, further comprising a regeneration assembly disposed on the condensate and feedwater line.
4. The steam turbine system of claim 3, wherein the regeneration assembly includes a low pressure heater bank coupled to low pressure steam within the main steam turbine and a high pressure heater bank coupled to high pressure steam within the main steam turbine.
5. The steam turbine system according to claim 4, wherein the low pressure heater group comprises a first low pressure heater (9), a second low pressure heater (10) and a third low pressure heater (11) connected in steps, the high pressure heater group comprises a first high pressure heater (15), a second high pressure heater (16) and a third high pressure heater (17) connected in steps, an inlet of the first low pressure heater (9) is connected with the hot well (7) through a first pressurizing member (8), an outlet of the low pressure heater (11) is connected with an inlet of the first high pressure heater (15), and an outlet of the third high pressure heater (17) is connected with the boiler (1).
6. The steam turbine system according to claim 5, wherein the number of coolers is three, three coolers being arranged between the first low-pressure heater (9) and the second low-pressure heater (10), between the second low-pressure heater (10) and the third low-pressure heater (11), between the third low-pressure heater (11) and the first high-pressure heater (15), respectively.
7. Turbine system according to claim 5, characterized in that the first low-pressure heater (9) and the second low-pressure heater (10) are respectively bypassed to the end and the middle section of the low-pressure cylinder (4), the third low-pressure heater (11) is bypassed to the end of the middle-pressure cylinder (3), the first high-pressure heater (15) is bypassed to the first section of the middle-pressure cylinder (3), and the second high-pressure heater (16) and the third high-pressure heater (17) are bypassed to the end and the middle section of the high-pressure cylinder (2), respectively.
8. The steam turbine system of claim 5, further comprising a deaerator (12) disposed between the third low pressure heater (11) and the first high pressure heater (15).
9. The steam turbine system of claim 8, further comprising a drive member (13) disposed between the deaerator (12) and the first high pressure heater (15), the drive member (13) having a second pressure member (14) disposed thereon.
10. The steam turbine system of claim 8, wherein the high pressure steam flows through the third high pressure heater (17), the second high pressure heater (16) and the first high pressure heater (15) in a stepwise manner and then flows into the deaerator (12), and the low pressure steam flows through the third low pressure heater (11), the second low pressure heater (10) and the first low pressure heater (9) in a stepwise manner and then flows into the thermal well (7).
CN202320636099.9U 2023-03-27 2023-03-27 Steam turbine system Active CN219654752U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202320636099.9U CN219654752U (en) 2023-03-27 2023-03-27 Steam turbine system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202320636099.9U CN219654752U (en) 2023-03-27 2023-03-27 Steam turbine system

Publications (1)

Publication Number Publication Date
CN219654752U true CN219654752U (en) 2023-09-08

Family

ID=87855666

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202320636099.9U Active CN219654752U (en) 2023-03-27 2023-03-27 Steam turbine system

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Country Link
CN (1) CN219654752U (en)

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