Steam parameter adjusting device of CCPP steam turbine

Abstract

The utility model relates to the technical field of power generation equipment, in particular to a steam parameter adjusting device of a CCPP steam turbine. The utility model provides a steam parameter adjusting device of a CCPP steam turbine, and the steam parameter adjusting device comprises a main pipeline which is used for connecting a waste heat boiler and the steam turbine; the pressure regulating pipeline is provided with an air inlet and an air outlet, the air inlet is connected with the main pipeline, and the air outlet is communicated with the outside; and the pressure regulating valve is arranged on the pressure regulating pipeline and is used for regulating the gas flow in the pressure regulating pipeline. By implementing the technical scheme disclosed by the invention, a temperature and pressure reduction device from main steam to seawater desalination can be reduced, the system flexibility is improved, and the gas turbine and the waste heat boiler system can still operate stably when a part of the steam turbine breaks down.

Description

Technical Field

[0001] The present disclosure relates to the technical field of power generation equipment, and in particular to a steam parameter adjustment device for a CCPP steam turbine. Background Art

[0002] At present, CCPP (gas-steam combined cycle power generation unit) power generation technology has become a trend in domestic steel enterprises. In coastal areas, the efficient coupling production mode of CCPP units and seawater desalination has been applied, in which the gas turbine and steam turbine adopt a split-axis arrangement. The large amount of flue gas generated after the gas turbine generates electricity is efficiently utilized through the waste heat boiler to generate high-temperature and high-pressure steam to drive the steam turbine to work. The steam turbine is not equipped with a condenser. After working, the exhaust steam all enters the seawater desalination device for reuse, and the low-temperature multi-effect distillation technology is adopted to produce desalted water.

[0003] The entire system has a long flow and complex process. The startup method is a sequential control process of starting the gas turbine to generate electricity plus the waste heat boiler to feed water for heat exchange or starting the steam turbine to generate electricity plus seawater desalination to start water production; the normal stop method is a sequential control process of stopping the unit when the gas turbine plus the waste heat boiler reduce the load, the steam turbine plus seawater desalination reduce the load, or the load of the four major devices are reduced to the set load; the fault stop method is a fault in any of the four major devices, the gas turbine, waste heat boiler, steam turbine or seawater desalination, and the unit stops.

[0004] The gas turbine itself has the characteristics of fast start and stop, but it takes a certain amount of time for the steam in the waste heat boiler to heat up and increase pressure and cool down and reduce pressure. At the same time, the steam turbine is affected by factors such as expansion difference and cylinder temperature difference, and the starting and load adjustment are restricted. In particular, when the CCPP unit is started as a whole or stopped due to a fault, the waste heat boiler steam cannot enter the steam turbine. Under this condition, the remaining units will enter the condenser through the main steam bypass system for direct cooling. However, since this unit uses a seawater desalination device instead of a condenser, a large amount of steam cannot meet the parameter requirements for directly entering the seawater desalination during start and shutdown. Utility Model Content

[0005] The present disclosure aims to solve at least one of the technical problems existing in the prior art or related art.

[0006] To this end, a first aspect of the present disclosure provides a steam parameter adjustment device for a CCPP steam turbine, comprising: a main pipeline for connecting a waste heat boiler and a steam turbine; a pressure regulating pipeline, the pressure regulating pipeline having an air inlet and an air outlet, the air inlet being connected to the main pipeline, and the air outlet being connected to the outside; and a pressure regulating valve, the pressure regulating valve being arranged on the pressure regulating pipeline and being used to adjust the gas flow in the pressure regulating pipeline.

[0007] In a feasible implementation manner, it further includes: a first stop valve, which is arranged on the pressure regulating pipeline and is used to cut off the gas in the pressure regulating pipeline.

[0008] In a feasible implementation manner, the first stop valve is arranged at an end close to the air inlet, and the pressure regulating valve is arranged at an end close to the air outlet.

[0009] In a feasible implementation manner, it further includes: a muffler, wherein the muffler is arranged on the air outlet.

[0010] In a feasible implementation, it further includes: a drain device, the drain device includes a pipeline body and a second stop valve, the pipeline body is connected to the pressure regulating pipeline, and the second stop valve is arranged on the pipeline body for cutting off the pipeline body.

[0011] In a feasible implementation manner, a manual drain valve is also provided on the pipeline body.

[0012] In a feasible implementation manner, it further includes: a detection device, which is connected to the main pipeline and is used to detect the pressure and temperature of the main pipeline.

[0013] In a feasible implementation manner, the detection device includes a pressure gauge and a temperature gauge, and the pressure gauge and the temperature gauge are arranged near one end of the main pipeline connected to the steam turbine, and the temperature gauge is close to the steam turbine.

[0014] In a feasible implementation manner, a third stop valve is provided at one end of the main pipeline close to the steam turbine, and the third stop valve is used to stop the gas in the main pipeline from entering the steam turbine.

[0015] In a second aspect of the present disclosure, a CCPP steam turbine is provided, comprising the steam parameter adjustment device for the CCPP steam turbine described above.

[0016] Compared with the prior art, the present disclosure includes at least the following beneficial effects: the present disclosure sets a main pipeline for connecting the waste heat boiler and the steam turbine, sets a pressure regulating pipeline on the main pipeline, the pressure regulating pipeline has an air inlet and an air outlet, the air inlet is connected to the main pipeline, and the air outlet is connected to the outside to relieve the pressure of the main pipeline; a pressure regulating valve is set on the pressure regulating pipeline, and the pressure regulating valve is set on the pressure regulating pipeline to adjust the gas flow in the pressure regulating pipeline. By implementing the technical solution of the present disclosure, the temperature and pressure reduction devices from the main steam to the seawater desalination can be reduced, the system flexibility can be improved, and when the steam turbine part fails, the gas turbine and waste heat boiler system can still operate stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0019] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the exemplary embodiments below. The accompanying drawings are only for the purpose of illustrating exemplary embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0020] Figure 1 It is a schematic diagram of the structure of the present invention.

[0021] in, Figure 1 The corresponding relationship between the reference numerals and the component names is as follows:

[0022] 100-waste heat boiler; 200-steam turbine;

[0023] 1-main pipeline; 2-pressure regulating pipeline; 21-air inlet; 22-air outlet; 3-pressure regulating valve; 4-first stop valve; 5-muffler; 6-pipeline body; 7-second stop valve; 8-drain manual valve; 9-pressure gauge; 10-temperature gauge; 11-third stop valve. DETAILED DESCRIPTION

[0024] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0025] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0026] The entire system has a long flow and complex process. The startup method is a sequential control process of starting the gas turbine to generate electricity plus the waste heat boiler to feed water for heat exchange or starting the steam turbine to generate electricity plus seawater desalination to start water production; the normal stop method is a sequential control process of stopping the unit when the gas turbine plus the waste heat boiler reduce the load, the steam turbine plus seawater desalination reduce the load, or the load of the four major devices are reduced to the set load; the fault stop method is a fault in any of the four major devices, the gas turbine, waste heat boiler, steam turbine or seawater desalination, and the unit stops.

[0027] The gas turbine itself has the characteristics of fast start and stop, but it takes a certain amount of time for the steam in the waste heat boiler to heat up and increase pressure and cool down and reduce pressure. At the same time, the steam turbine is affected by factors such as expansion difference and cylinder temperature difference, and the starting and load adjustment are restricted. In particular, when the CCPP unit is started as a whole or stopped due to a fault, the waste heat boiler steam cannot enter the steam turbine. Under this condition, the remaining units will enter the condenser through the main steam bypass system for direct cooling. However, since this unit uses a seawater desalination device instead of a condenser, a large amount of steam cannot meet the parameter requirements for directly entering the seawater desalination during start and shutdown.

[0028] Based on this, an embodiment of the present disclosure provides a steam parameter adjustment device for a CCPP steam turbine. By implementing the technical solution of the present disclosure, the number of cooling and pressure reducing devices for main steam to seawater desalination can be reduced, thereby improving the flexibility of the system. When a partial failure of the steam turbine occurs, the gas turbine and waste heat boiler system can still operate stably.

[0029] The steam parameter adjustment device of the CCPP steam turbine is described in detail below through a specific embodiment:

[0030] Reference Figure 1 As shown, the present disclosure provides a steam parameter adjustment device for a CCPP steam turbine, comprising a main pipeline 1 for connecting a waste heat boiler 100 and a steam turbine 200; a pressure regulating pipeline 2, the pressure regulating pipeline 2 having an air inlet 21 and an air outlet 22, the air inlet 21 being connected to the main pipeline 1, and the air outlet 22 being connected to the outside; and a pressure regulating valve 3, the pressure regulating valve 3 being arranged on the pressure regulating pipeline 2, and being used for adjusting the gas flow in the pressure regulating pipeline 2.

[0031] The present disclosure reduces the pressure in the main pipeline 1 by setting a pressure regulating pipeline 2 on the main pipeline 1, so that the steam parameters during the start and stop of the steam turbine 200 meet the system requirements. The pressure regulating pipeline 2 of the present disclosure has an air inlet 21 and an air outlet 22, the air inlet 21 is connected to the main pipeline 1, and the air outlet 22 is connected to the outside for discharging gas to the outside. The specific setting method of the pressure regulating pipeline 2 of the present disclosure can be selected to be vertical to the pipeline body 1, so that the exhaust is more direct and smooth. When a fault occurs and the turbine is shut down during normal operation, the main steam valve protection action is closed, the pressure of the main pipeline 1 rises instantly, and the main steam parameters from the waste heat boiler to the turbine rise from 465-495℃, 7-8.7MPa to 495-505℃, 10MPa, exceeding the pipeline pressure safety value of 505℃, 9MPa. At this time, the gas flow to the outside in the pressure regulating pipeline 2 is adjusted by adjusting the opening and closing degree of the pressure regulating valve 3, thereby adjusting the pressure in the main pipeline 1 to a safe range.

[0032] In some embodiments, the present disclosure further includes a first stop valve 4 , which is disposed on the pressure regulating pipeline 2 and is used to stop the gas in the pressure regulating pipeline 2 .

[0033] In this embodiment, the first stop valve 4 is arranged on the pressure regulating pipeline 2. When the pressure regulating pipeline 2 needs maintenance or replacement of the pressure regulating valve 3, the first stop valve 4 can be used to stop the pressure regulating pipeline 2 so that the gas cannot be discharged; when the pressure regulating valve 3 fails, the first stop valve 4 can also be used as an emergency switch.

[0034] In some embodiments, the first stop valve 4 is disposed at an end close to the air inlet 21 , and the pressure regulating valve 3 is disposed at an end close to the air outlet 22 , so as to facilitate maintenance of the pressure regulating valve 3 .

[0035] In some embodiments of the present disclosure, a muffler 5 is further included, and the muffler 5 is arranged on the air outlet 22. In this embodiment, the muffler 5 is arranged to eliminate the noise generated by the air outlet 22 when the pressure is released, thereby preventing the noise from affecting some voice control devices.

[0036] In some embodiments, a hydrophobic device is also included, which includes a pipeline body 6 and a second stop valve 7. The pipeline body 6 is connected to the pressure regulating pipeline 2. The second stop valve 7 is arranged on the pipeline body 6 to cut off the pipeline body 6.

[0037] In this embodiment, the pipeline body 6 is connected to the pressure regulating pipeline. It can be understood that in order to achieve the purpose of draining, the pipeline body 6 should be lower than the pressure regulating pipeline 2, so that the condensed water in the pipeline body 6 can flow out of the pipeline body 6. Optionally, a drain device or a drain tank is provided at the end of the pipeline body 6 where the condensed water flows out. In order to ensure that the pressure pipeline body 6 of the pressure regulating pipeline 2 cannot be in a draining state all the time, a second stop valve 7 is provided on the pipeline body 6 to stop the pipeline body 6 when draining should be stopped.

[0038] In some embodiments, a manual drain valve 8 is further provided on the pipeline body 6 of the present disclosure, and the manual drain valve 8 can be used to drain water when the second stop valve 7 fails and water needs to be drained. Optionally, the manual drain valve 8 is provided on a side closer to the pressure regulating pipeline 2 to prevent the second stop valve 7 from failing in the stopped state, resulting in failure to effectively drain water.

[0039] In some embodiments, the present disclosure further includes a detection device, which is connected to the main pipeline 1 and is used to detect the pressure and temperature of the main pipeline 1 .

[0040] In some embodiments, the detection device of the present disclosure includes a pressure gauge 9 and a temperature gauge 10 , which are arranged near one end of the main pipeline 1 connected to the steam turbine 200 , and the temperature gauge 10 is close to the steam turbine 200 .

[0041] In some embodiments, a third stop valve 11 is provided at one end of the main pipeline 1 of the present disclosure close to the steam turbine 200, and the third stop valve 11 is used to stop the gas in the main pipeline 1 from entering the steam turbine 200, so as to achieve further pressure regulation and complete shutoff of the main pipeline 1 to the steam turbine 200.

[0042] It can be understood that the first stop valve 4, the second stop valve 7 and the third stop valve 11 of the present disclosure are all electric stop valves for easy control.

[0043] The following is an introduction to an embodiment of a specific use condition, which is a combination of one or more of the above embodiments, and is as follows:

[0044] See also Figure 1 When the unit is not started and is operating normally, the first stop valve 4, the pressure regulating valve 3 and the second stop valve 7 are kept in a fully closed state. The steam trap manual valve 8 is closed except when the second stop valve 7 fails and needs to be replaced, and is kept in an open state at other times.

[0045] When the unit is started, the engine is ignited, the first stop valve 4 and the pressure regulating valve 3 are fully opened, and after the engine reaches a stable operating condition, the first stop valve 4 is fully opened, and the pressure regulating valve 3 automatically adjusts the opening according to the main steam pressure, maintaining the main steam pressure P1 = 2.5MPa and the temperature T1 = 230℃-250℃ after the device, and the excess steam is discharged to the atmosphere through the muffler 5. The steam turbine is run, and after the gas turbine and the steam turbine both reach 3000rpm, they are connected to the grid for power generation. After the pressure regulating valve 3 is slowly closed, the first stop valve 4 is fully closed. The main steam enters the steam turbine, and the gas turbine and the steam turbine begin to increase the load. Among them, the second stop valve 7 is opened for 100s after the first stop valve 4 is closed, and the second stop valve 7 is closed after the drainage is completed.

[0046] When the unit stops (normal or faulty), after the control system receives the shutdown signal, the first stop valve 4 and the pressure regulating valve 3 are all interlocked and opened. When P1 is less than 1MPa, the pressure regulating valve 3 is slowly closed, and the first stop valve 4 is fully closed. Among them, the second stop valve 7 is opened for 100s after the first stop valve 4 is closed, and the second stop valve 7 is closed after the drainage is completed.

[0047] When the steam turbine 200 is abnormal and the steam inlet volume is reduced, the main steam pressure exceeds 9.0 MPa, the first stop valve 4 and the pressure regulating valve 3 are all interlocked and opened. When the main steam pressure is lower than 7.0 MPa, the pressure regulating valve 3 is slowly closed, and then the first stop valve 4 is fully closed. Among them, the second stop valve 7 is opened for 100 seconds after the first stop valve 4 is closed, and the second stop valve 7 is closed after the drainage is completed.

[0048] In a second aspect of the present disclosure, a CCPP steam turbine is provided, comprising the steam parameter adjustment device for the CCPP steam turbine described above.

[0049] In the present disclosure, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise expressly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood according to the specific circumstances.

[0050] In the description of the present disclosure, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "left", "right", "front", "back", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, should not be understood as a limitation on the present disclosure.

[0051] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0052] The above are only preferred embodiments of the present disclosure and are not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A steam parameter adjustment device for a CCPP steam turbine, It is characterized in that include: Main pipeline, used to connect the waste heat boiler and the steam turbine; A pressure regulating pipeline, the pressure regulating pipeline having an air inlet and an air outlet, the air inlet is connected to the main pipeline, and the air outlet is connected to the outside; A pressure regulating valve is arranged on the pressure regulating pipeline and is used to adjust the gas flow in the pressure regulating pipeline.

2. The steam parameter adjustment device for a CCPP steam turbine according to claim 1, It is characterized in that Also includes: A first stop valve is arranged on the pressure regulating pipeline and is used to stop the gas in the pressure regulating pipeline.

3. The steam parameter adjustment device for CCPP steam turbine according to claim 2, It is characterized in that The first stop valve is arranged at one end close to the air inlet, and the pressure regulating valve is arranged at one end close to the air outlet.

4. The steam parameter adjustment device for a CCPP steam turbine according to claim 1, It is characterized in that Also includes: A muffler is arranged on the air outlet.

5. The steam parameter adjustment device for a CCPP steam turbine according to claim 1, It is characterized in that Also includes: A drain device, the drain device includes a pipeline body and a second stop valve, the pipeline body is connected to the pressure regulating pipeline, and the second stop valve is arranged on the pipeline body and is used to cut off the pipeline body.

6. The steam parameter adjustment device for CCPP steam turbine according to claim 5, It is characterized in that The pipeline body is also provided with a manual drain valve.

7. The steam parameter adjustment device for a CCPP steam turbine according to claim 1, It is characterized in that Also includes: A detection device is connected to the main pipeline and is used to detect the pressure and temperature of the main pipeline.

8. The steam parameter adjustment device for a CCPP steam turbine according to claim 7, It is characterized in that The detection device comprises a pressure gauge and a temperature gauge, wherein the pressure gauge and the temperature gauge are arranged near one end of the main pipeline connected to the steam turbine, and the temperature gauge is close to the steam turbine.

9. The steam parameter adjustment device for a CCPP steam turbine according to claim 1, It is characterized in that A third stop valve is provided at one end of the main pipeline close to the steam turbine, and the third stop valve is used to stop the gas in the main pipeline from entering the steam turbine.

10. A CCPP steam turbine, It is characterized in that A steam parameter adjustment device for a CCPP steam turbine comprising any one of claims 1 to 9.

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