阅读说明：本技术 一种用于抽凝式改背压式空冷汽轮机组的疏水排汽结构 (A drainage steam exhaust structure for taking out condensing change back pressure formula air cooling steam turbine group ) 是由 侯佩印 吴玲玲 李清 张昊 高青 李洋 谢微 王婷婷 于 2020-07-07 设计创作，主要内容包括：本发明提供了一种用于抽凝式改背压式空冷汽轮机组的疏水排汽结构,属于空冷汽轮发电机组的疏水、排汽技术领域,以解决现有的汽轮机排汽结构,蒸汽在排出时容易出现低压缸返汽,通过通入空冷岛的蒸汽容易结冻损坏设备及系统,并影响汽轮机的安全运行的问题。本发明包括进汽管路组件、热井、排汽装置、堵板、导流板和回流管；排汽装置设有堵板、导流板、排汽口和低压蒸汽口,低压蒸汽口与汽轮机低压缸连通,堵板位于低压蒸汽口和排汽装置上的排汽口之间并将低压蒸汽口和排汽口隔断,进汽管路组件穿过堵板设置,导流板相对进汽管路组件蒸汽出口设置,使进汽管路组件排出的蒸汽能沿着导流板从排汽装置上的排汽口排出。本发明适用于汽轮机。(The invention provides a drainage steam exhaust structure for a steam extraction condensing type back pressure type air-cooled steam turbine unit, belongs to the technical field of drainage and steam exhaust of air-cooled steam turbine units, and aims to solve the problems that low-pressure cylinder steam return is easy to occur when steam is exhausted, equipment and a system are easy to freeze and damage through the steam introduced into an air cooling island, and the safe operation of a steam turbine is influenced in the existing steam turbine steam exhaust structure. The invention comprises a steam inlet pipeline component, a hot well, a steam exhaust device, a blocking plate, a flow guide plate and a return pipe; the steam exhaust device is provided with a blocking plate, a guide plate, a steam exhaust port and a low-pressure steam port, the low-pressure steam port is communicated with a low-pressure cylinder of the steam turbine, the blocking plate is located between the low-pressure steam port and the steam exhaust port on the steam exhaust device and separates the low-pressure steam port from the steam exhaust port, the steam inlet pipeline assembly penetrates through the blocking plate, the guide plate is arranged opposite to the steam outlet of the steam inlet pipeline assembly, and steam exhausted by the steam inlet pipeline assembly can be exhausted from the steam exhaust port on the steam exhaust device along the guide plate. The invention is suitable for steam turbines.)

1. A drainage steam exhaust structure for a steam extraction condensing back-pressure air-cooled steam turbine unit comprises a steam inlet pipeline assembly, a hot well (5), a steam exhaust device (4) and a return pipe (14), and is characterized by further comprising a blocking plate (11) and a guide plate (12);

the steam exhaust device (4) is provided with a blocking plate (11), a guide plate (12), a steam exhaust port (13) and a low-pressure steam port, the low-pressure steam port is communicated with a low-pressure cylinder of a steam turbine, the blocking plate (11) is located between the low-pressure steam port and the steam exhaust port (13) on the steam exhaust device (4) and separates the low-pressure steam port from the steam exhaust port (13), a steam inlet pipeline assembly penetrates through the blocking plate (11), the guide plate (12) is arranged opposite to a steam outlet of the steam inlet pipeline assembly, steam exhausted by the steam inlet pipeline assembly can be exhausted from the steam exhaust port (13) on the steam exhaust device (4) along the guide plate (12), and the steam exhaust device (4) is communicated with the hot well (5) through a return pipe (14).

2. The steam discharge structure of claim 1, wherein the guide plate (12) is formed in a circular arc shape, and the concave surface of the guide plate (12) is disposed toward the block plate (11) of the steam discharge pipe (9).

3. The steam-drainage steam-exhaust structure for the extraction-condensation back-pressure air-cooled steam turbine unit according to claim 1, wherein the steam-inlet pipeline assembly comprises a steam turbine steam-drainage pipeline (2), a steam-drainage flash tank (3) and a steam-exhaust pipe (9), the steam turbine steam-drainage pipeline (2) is communicated with the steam-drainage flash tank (3), a steam outlet on the steam-drainage flash tank (3) is communicated with the steam-exhaust device (4) through the steam-exhaust pipe (9), the steam-exhaust pipe (9) passes through the blocking plate (11), the steam-exhaust pipe (9) is arranged opposite to the flow guide plate (12), and the steam-drainage flash tank (3) is communicated with the hot well (5) through the water-exhaust pipe (16).

4. The steam drainage and exhaust structure for the extraction and condensation type back pressure air-cooled steam turbine unit as claimed in claim 3, wherein the steam inlet pipeline assembly further comprises a high pressure heater (17) and a high pressure heater steam exhaust pipeline (6), the high pressure heater is communicated with the steam exhaust device (4) through the high pressure heater steam exhaust pipeline (6), and the high pressure heater steam exhaust pipeline (6) is arranged to penetrate through the blocking plate (11).

5. The steam drainage and exhaust structure for the extraction and condensation type back pressure air-cooled steam turbine unit as claimed in claim 4, wherein the steam inlet pipeline assembly further comprises a low pressure heater (16) and a low pressure heater steam exhaust pipeline (7), the low pressure heater (16) is communicated with the steam exhaust device (4) through the low pressure heater steam exhaust pipeline (7), and the low pressure heater steam exhaust pipeline (7) is arranged to penetrate through the blocking plate (11).

6. The steam drainage and exhaust structure for the extraction and condensation type back pressure air-cooled steam turbine unit as claimed in claim 5, wherein the steam inlet pipeline assembly further comprises a heat net heater (18) and a heat net heater steam exhaust pipeline (8), the heat net heater is communicated with the steam exhaust device (4) through the heat net heater steam exhaust pipeline (8), and the heat net heater steam exhaust pipeline (8) is arranged through the blocking plate (11).

7. The steam discharge structure for an extraction-condensation back-pressure air-cooled steam turbine unit according to claim 6, wherein the steam intake line assembly further comprises a sealing water protection water pipe (10), and the sealing water protection water pipe (10) passes through the blocking plate (11) and communicates with the steam discharge device (4).

8. The steam-drainage structure for the extraction-condensation back-pressure air-cooled steam turbine unit according to claim 7, wherein the steam inlet pipeline assembly further comprises a shaft-added steam trap and a shaft-added steam trap pipe (15), and the shaft-added steam trap is communicated with the hot well (5) through the shaft-added steam trap pipe (15).

9. The steam trap structure of claim 7, wherein the inlet of the return pipe (14) is located on the steam-back side of the deflector (12).

Technical Field

The invention relates to a drainage and steam exhaust structure for a steam extraction and condensation type back pressure type air-cooled steam turbine unit, and belongs to the technical field of drainage and steam exhaust of air-cooled steam turbine units.

Background

In 2016, 3 and 22 months, the United states of the Ministry of development and improvement, the State energy agency, the department of finance, the department of construction and residential and environmental protection jointly printed the management method of cogeneration. The generated energy of the cogeneration unit is preferentially purchased by power grid enterprises according to the principle of 'fixing power by heat', and the back pressure type steam turbine generator unit is preferentially adopted in the heating type combined cycle project.

With the continuous emergence of 600MW, 1000MW heat supply unit, under the encouragement and the promotion of national energy saving and emission reduction policy, 200MW air cooling drainage condensing unit faces the danger of being eliminated, reforms transform into the necessary trend of backpressure unit constitution, reforms transform back heating power and promotes, and waste heat loss is zero, and energy saving and consumption reduction effect is outstanding.

After the air cooling condensing unit is transformed into a back pressure unit, the air cooling condensing unit is only put into operation in the winter heating season. The low pressure rotor is changed into an optical axis or a balance weight impeller is added, the upper part of the low pressure cylinder of the steam turbine is detached from an atmospheric valve, and the lower part of the low pressure cylinder of the steam turbine is still connected with a steam exhaust pipeline without being changed. The structure before improvement is shown in fig. 1, before improvement, wet steam generated by a low-pressure cylinder, a drain flash tank 3, a low-pressure heater 21, a high-pressure heater 17, a heating network heater 18 and a shaft heater 19 on a steam turbine 1 enters an exhaust device 4, enters an air cooling island, is condensed into water, flows back into a hot well 5 through a return pipe 14, and finally returns the water in the hot well 5 to a boiler for reuse.

The unit after backpressure transformation still needs to utilize exhaust pipe and hot-well when running, and the steam that has existed in the exhaust pipe and produces by each way drainage, and steam that these wet steam and low pressure jar produced all gets into exhaust apparatus, and the steam pressure imbalance in the steam pressure in each way drainage pipeline of wet steam that each way drainage produced, these wet steam partly lead to the air cooling island, and another part is then returned the low pressure jar. The steam leading to the air cooling island part is easy to freeze and damage equipment and a system in winter, and the steam returning to the low-pressure cylinder part enables the low-pressure cylinder to be in a high-temperature and humid state for a long time, so that the two phenomena have great influence on the safe operation of the unit. The existing common solution is to add a condenser, and two methods increase investment or operation cost and increase plant power consumption, and the system is complex and has freezing risk.

Disclosure of Invention

The invention provides a multi-degree-of-freedom transposition anti-seismic connecting piece, aiming at solving the problems that in the existing steam turbine steam exhaust structure, low-pressure cylinder steam return is easy to occur when steam is exhausted, equipment and a system are easy to freeze and damage through the steam introduced into an air cooling island, and the safe operation of a steam turbine is influenced.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a drainage steam exhaust structure for a steam extraction condensing type back pressure type air-cooled steam turbine unit comprises a steam inlet pipeline assembly, a hot well, a steam exhaust device, a blocking plate, a guide plate and a return pipe;

the steam exhaust device is provided with a blocking plate, a guide plate, a steam exhaust port and a low-pressure steam port, the low-pressure steam port is communicated with a low-pressure cylinder of the steam turbine, the blocking plate is located between the low-pressure steam port and the steam exhaust port on the steam exhaust device and separates the low-pressure steam port from the steam exhaust port, the steam inlet pipeline assembly penetrates through the blocking plate, the guide plate is arranged opposite to the steam outlet of the steam inlet pipeline assembly, steam exhausted by the steam inlet pipeline assembly can be exhausted from the steam exhaust port on the steam exhaust device along the guide plate, and the steam exhaust device is communicated with the hot well through a return pipe.

Preferably, the shape of the guide plate is circular arc, and the concave surface of the guide plate faces the steam exhaust pipe blocking plate.

Preferably, the steam inlet pipeline assembly comprises a steam turbine drain pipeline, a drain flash tank and a steam exhaust pipe, the steam turbine drain pipeline is communicated with the drain flash tank, a steam outlet on the drain flash tank is communicated with a steam exhaust device through the steam exhaust pipe, the steam exhaust pipe penetrates through the blocking plate, the steam exhaust pipe is arranged opposite to the guide plate, and the drain flash tank is communicated with the hot well through the water exhaust pipe.

Preferably, the steam inlet pipeline assembly further comprises a high-pressure heater and a high-pressure heater steam exhaust pipeline, the high-pressure heater is communicated with the steam exhaust device through the high-pressure heater steam exhaust pipeline, and the high-pressure heater steam exhaust pipeline penetrates through the blocking plate.

Preferably, the steam inlet pipeline assembly further comprises a low-pressure heater and a low-pressure heater steam exhaust pipeline, the low-pressure heater is communicated with the steam exhaust device through the low-pressure heater steam exhaust pipeline, and the low-pressure heater steam exhaust pipeline penetrates through the blocking plate.

Preferably, the steam inlet pipeline assembly further comprises a heat supply network heater and a heat supply network heater steam exhaust pipeline, the heat supply network heater is communicated with the steam exhaust device through the heat supply network heater steam exhaust pipeline, and the heat supply network heater steam exhaust pipeline penetrates through the blocking plate.

Preferably, the steam inlet pipeline assembly further comprises a sealing water protection water pipeline, and the sealing water protection water pipeline penetrates through the blocking plate and is communicated with the steam exhaust device.

Preferably, the steam inlet pipeline assembly further comprises a shaft-added steam trap and a shaft-added steam trap pipe, and the shaft-added steam trap is communicated with the hot well through the shaft-added steam trap pipe.

Preferably, the water inlet of the return pipe is positioned on the steam-back side of the deflector.

Compared with the prior art, the invention has the following beneficial effects:

1. the air cooling island is shut down, and a large amount of auxiliary electricity is saved. The unit runs stably, the air cooling island stops running, a large amount of service power is saved, energy conservation and emission reduction are realized, and the profitability of a power plant is enhanced.

2. And a condenser is not required to be additionally arranged, so that the investment is saved. The system is simple, a condensing system and equipment do not need to be additionally arranged, the space restriction is avoided, the investment and the operation cost are reduced, and the stable operation of the unit is ensured.

3. The steam return phenomenon of the low-pressure cylinder is not generated. After the air cooling unit backpressure is reformed transform, because steam still converges to exhaust apparatus, so newly increase the closure plate in exhaust apparatus, each exhaust steam pipeline passes the closure plate, and the closure plate blocks steam, and steam can't return low pressure cylinder chamber from the low pressure steam port, keeps the unit steady operation.

4. The air cooling tower has no freezing risk. After the air cooling unit is subjected to backpressure reformation, steam still converges to the steam exhaust device, and each drain still converges to the hot well, so a guide plate is additionally arranged at the steam exhaust port of the steam exhaust device, steam exhausted by the steam exhaust pipe and wet steam generated by the drain converging to the hot well are exhausted into the atmosphere through the steam exhaust port, a large amount of steam is prevented from entering the air cooling island, only a small amount of wet steam which is not exhausted enters the air cooling island and is condensed into water, and finally, the water is exhausted into the hot well through the return pipe. The air cooling island has no freezing risk, and the unit can keep stable operation.

Drawings

FIG. 1 is a schematic illustration of the present invention prior to modification;

FIG. 2 is a schematic view of a modification of the present invention;

FIG. 3 is a schematic view of a baffle;

reference numerals in the drawings: the steam turbine is characterized in that 1 is a steam turbine, 2 is a steam turbine drainage pipeline, 3 is a drainage flash tank, 4 is a steam exhaust device, 5 is a hot well, 6 is a high-pressure heater steam exhaust pipeline, 7 is a low-pressure heater steam exhaust pipeline, 8 is a heat supply network heater steam exhaust pipeline, 9 is a steam exhaust pipe, 10 is a sealing water protection water pipeline, 11 is a blocking plate, 12 is a guide plate, 13 is a steam exhaust port, 14 is a return pipe, 15 is a drainage pipeline, 16 is a drain pipe, 17 is a high-pressure heater, 18 is a heat supply network heater, 19 is a steam seal heater, 20 is a shaft steam trap, and 21 is a low-pressure heater.

Detailed Description

The invention will be described in further detail below with reference to the accompanying drawings: the present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation is given, but the scope of the present invention is not limited to the following embodiments.