Steam-driven induced draft fan device coupled with steam source and system of steam-driven induced draft fan device

Abstract

The invention discloses a steam-driven induced draft fan device coupled with a steam source and a system of the steam-driven induced draft fan device. The steam-driven induced draft fan device comprises a small steam-driven induced draft fan, a pipeline unit, a valve unit, a secondary steam source pipeline unit and a secondary pipeline valve unit. The steam-driven induced draft fan device has the beneficial effects that by designing the steam-driven induced draft fan device coupled with the high-pressure standby steam source, the problem of insufficient conventional steam supply under deep peak regulation, low load and other special working conditions of the boiler is solved. And stable operation of the small turbine of the induced draft fan is ensured, so that operation interruption and equipment faults caused by insufficient pressure of a low-pressure steam source are avoided, the adaptability of a system can be effectively improved, the small turbine of the induced draft fan can obtain enough steam support under various complex working conditions, and stable output is ensured. Meanwhile, through reasonable steam regulation and control, the operation safety of the system is remarkably improved, risks caused by pressure fluctuation or overpressure are reduced, the service life of equipment is prolonged, and the overall operation reliability of the equipment is improved.

Description

Technical Field

[0001] The invention relates to the technical field of steam-driven induced draft fans, in particular to a steam-driven induced draft fan device coupled with a steam source and a system thereof. Background Art

[0002] During the process of reducing the output of the boiler, especially during deep peak regulation, the steam pressure of the first-stage reheater decreases, and the small steam turbine valve gradually opens or even fully opens. When the steam source parameters are too low, even if the valve is fully opened, the small induced draft fan cannot reach the corresponding output, and thus cannot meet the requirements of the induced draft fan to adjust the furnace negative pressure. At present, during deep peak regulation, the main method used is to manually open the high and low pressure bypass to control the steam pressure of the first-stage reheater at around 1.8-2.0MPa to ensure the normal operation of the small induced draft fan. The operation volume of controlling the reheat steam pressure through the high and low pressure bypass is large, and a dedicated person is required to monitor the steam pressure. Before the boiler is deeply adjusted to stop operation, the steam pressure at the outlet of the second-stage superheater can be maintained above 9MPa and the temperature is around 480℃. Therefore, the steam parameters at the outlet of the second-stage superheater need to meet the operating requirements of the small induced draft fan during deep peak regulation of the unit.

[0003] After the boiler is shut down and before purging, the high and medium pressure steam valves and high and low pressure bypasses of the steam turbine have been closed, the reheat steam source is interrupted and the remaining steam pressure is low, generally about 1MPa, which cannot meet the requirements of connecting the small steam source of the induced draft fan. When the boiler is shut down, the steam pressure at the outlet of the secondary superheater can be maintained at about 9MPa and the temperature is about 480℃. Therefore, the steam parameters at the outlet of the secondary superheater need to be reduced in pressure to meet the operating output requirements of the small induced draft fan during boiler purging and to ensure normal boiler shutdown purging.

[0004] After the boiler is ignited and starts to heat up and increase the pressure, generally when the rated load reaches 20-30% at the initial stage of the unit being connected to the grid, the steam pressure at the outlet of the main steam secondary superheater reaches 9.5MPa and the temperature is around 460℃, which can basically meet the steam supply parameter requirements of the small induced draft fan. The reheat steam parameters need to be connected to 40% of the rated load to meet the output requirements of the small induced draft fan. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0006] In view of the above problems or problems existing in the prior art, the present invention is proposed.

[0007] Therefore, the object of the present invention is to provide a steam-driven induced draft fan device and a system thereof coupled with a steam source, which can meet the output requirements of the boiler in different working states through pipeline coupling and can adaptively switch the pipeline steam source.

[0008] In order to solve the above technical problems, the present invention provides the following technical solutions: a steam-driven induced draft fan device coupled with a steam source, comprising a pipeline unit for introducing a high-pressure standby steam source;

[0009] The valve unit connected to the pipeline unit can regulate and control the steam source in the pipeline unit.

[0010] As a preferred solution of the steam-driven induced draft fan device coupled with a steam source of the present invention, the piping unit includes a secondary superheater outlet mother pipe, a main pipeline connected to the secondary superheater outlet mother pipe, a branch pipeline connected to the main pipeline to assist the normal operation of the main pipeline, and a steam-driven induced draft fan small unit steam supply mother pipe connected to the steam-driven induced draft fan small unit.

[0011] As a preferred solution of the steam-driven induced draft fan device coupled to the steam source of the present invention, the valve unit includes a manual steam supply door for manually closing when the high-pressure standby steam source is not needed, so as to isolate the standby steam source and prevent high-pressure steam from entering the low-pressure steam source pipeline due to misoperation.

[0012] As a preferred solution of the steam-driven induced draft fan device coupled with a steam source of the present invention, the valve unit includes a branch valve to discharge residual moisture in the pipeline to ensure that the steam enters the induced draft fan unit dry.

[0013] As a preferred solution of the steam-driven induced draft fan device coupled to a steam source of the present invention, the valve unit includes a steam supply electric shut-off valve for controlling the on-off of the high-pressure steam source.

[0014] As a preferred solution of the steam-driven induced draft fan device coupled with a steam source of the present invention, the valve unit includes a steam supply pneumatic pressure regulating valve for adjusting the steam supply pressure to the operating requirements of the small steam turbine of the induced draft fan;

[0015] The valve unit includes a steam supply check valve for preventing steam cross-flow between high-pressure and low-pressure steam sources;

[0016] The valve unit includes a steam supply check valve and a rear manual valve which are used to isolate the high-pressure steam source when necessary to prevent it from entering the low-pressure steam source.

[0017] As a preferred solution of the steam-driven induced draft fan device coupled with a steam source of the present invention, the branch pipeline includes two groups of drain branches and a pressure relief branch;

[0018] The two sets of drain branches are respectively located between the steam supply manual door and the steam supply electric stop door, and between the steam supply check valve and the manual door behind the steam supply check valve;

[0019] The branch valves include a drain electric door and a drain manual door connected to two sets of drain branches, and a safety door connected to the pressure relief branch;

[0020] The electric drain door and manual drain door can be started before the high-pressure standby steam source is switched to discharge the residual moisture in the pipeline to ensure that the steam enters the induced draft fan dry unit;

[0021] The safety door is used to protect the small steam turbine of the induced draft fan.

[0022] In order to solve the above technical problems, the present invention provides the following technical solutions: a steam source pipeline unit, which is provided with two groups of re-export headers connected to the two A / B sides respectively, and can be used to introduce the boiler re-export steam;

[0023] A repetitive pipeline valve unit, which is connected to a repetitive steam source pipeline unit and can be used to adjust the steam source in the repetitive steam source pipeline unit;

[0024] The steam source pipeline unit is connected to the pipeline unit;

[0025] The recirculating valve unit is used to control the steam source in the recirculating valve unit to assist in switching the steam source.

[0026] As a preferred solution of the high-pressure steam source switching system of the present invention, wherein: the one-way steam source pipeline unit includes two groups of one-way pipelines, and two groups of one-way drain pipes connected to the one-way pipelines;

[0027] The reciprocating pipeline valve unit includes a reciprocating steam supply electric stop valve arranged on the reciprocating pipeline, a reciprocating check valve along the reciprocating pipeline close to the induced draft fan, and a reciprocating drain electric door and a reciprocating drain manual door arranged on the reciprocating drain pipe.

[0028] As a preferred solution of the high-pressure steam source switching system of the present invention, the pipeline unit is provided with temperature measuring points and pressure measuring points for placing temperature sensors and pressure sensors, and temperature sensors and pressure sensors can be placed to monitor the steam temperature and pressure in the pipeline in real time to ensure that the steam parameters meet the operating requirements of the induced draft fan small steam turbine, and send out an alarm signal or automatically control the pneumatic pressure regulating valve for adjustment when an abnormality is detected.

[0029] Beneficial effects of the present invention: The present invention provides a flexible and safe backup steam supply path based on the original conventional low-pressure steam source by coupling the design of the high-pressure backup steam source, so that the original low-pressure steam source is converted into a high-pressure steam source. Therefore, the steam parameters at the outlet of the secondary superheater meet the operating output requirements of the induced draft fan during boiler purging after pressure reduction, and can ensure the normal purging of the boiler during shutdown, thus achieving the independence and stability of steam supply under different working conditions; by adjusting and controlling the backup high-pressure steam source, the stability and efficient use of steam parameters are guaranteed. On the whole, the present invention not only improves the safety and economy of the system, but also provides a more stable operation guarantee under special working conditions such as deep peak regulation, shutdown purging and startup of the boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0031] Figure 1 The figure is a schematic diagram of the overall process of a steam-driven induced draft fan device coupled with a steam source.

[0032] Figure 2 The figure is a schematic diagram of the overall process of a steam-driven induced draft fan device coupled with a steam source.

[0033] Figure 3 This is a schematic diagram of the high-pressure steam source switching system. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0035] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0036] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0037] Example 1

[0038] Reference Figure 1, which is the first embodiment of the present invention, provides a steam-driven induced draft fan device coupled with a steam source, which includes a pipeline unit 100 and a valve unit 200, which can realize the use of a high-pressure steam source in the pipeline and adjust the valve unit 200 to meet its output requirements.

[0039] The pipeline unit 100 is used to introduce a high-pressure standby steam source;

[0040] The valve unit 200 connected to the pipeline unit 100 can regulate and control the steam source in the pipeline unit 100 .

[0041] The pipeline unit 100 is mainly responsible for leading the high-pressure standby steam source from the outlet of the secondary superheater on the A / B side of the boiler, and delivering the high-pressure steam to the small steam turbine of the induced draft fan through the pipeline. The purpose of this pipeline design is to provide a high-pressure standby steam source. When the conventional low-pressure reheat steam cannot provide sufficient pressure under the deep peak regulation or low-load conditions of the boiler, the standby high-pressure steam enters the system through the pipeline to ensure that the small induced draft fan can still maintain normal operation.

[0042] The valve unit 200 is used to control the activation of the high-pressure steam source, adjust the pressure and ensure the safe operation of the system.

[0043] The valve unit 200 ensures the safety and flexibility of the use of the backup high-pressure steam source through multi-level control, making the start and stop operation of the backup steam source simple and safe; ensuring that the high-pressure steam source will not cause excessive pressure on the induced draft fan; and preventing equipment damage or system failure due to excessive pressure.

[0044] In summary, by designing a steam-driven induced draft fan device coupled with a high-pressure standby steam source, the problem of insufficient conventional steam supply under deep peak regulation of the boiler, low load and other special working conditions is solved. The stable operation of the induced draft fan small steam turbine is ensured, thereby avoiding operation interruptions and equipment failures caused by insufficient pressure of the low-pressure steam source. The adaptability of the system can be effectively improved, so that the induced draft fan small unit can obtain sufficient steam support under a variety of complex working conditions to ensure stable output. At the same time, through reasonable steam regulation and control, the operating safety of the system has been significantly improved, reducing the risks caused by pressure fluctuations or overpressure, and enhancing the service life of the equipment and the overall operational reliability.

[0045] Example 2

[0046] Reference Figures 1-2 , which is the second embodiment of the present invention, provides a steam-driven induced draft fan device coupled with a steam source, which includes a pipeline unit 100 and a valve unit 200, which can realize the use of a high-pressure steam source in the pipeline and adjust the valve unit 200 to meet its output requirements.

[0047] Specifically, the pipeline unit 100 is used to introduce a high-pressure standby steam source;

[0048] The valve unit 200 connected to the pipeline unit 100 can regulate and control the steam source in the pipeline unit 100 .

[0049] Furthermore, the piping unit 100 includes a secondary superheater outlet mother pipe 101, a main pipe 102 connected to the secondary superheater outlet mother pipe 101, and a branch pipe 103 connected to the main pipe to assist the normal operation of the main pipe 102, and a steam-driven induced draft fan small unit steam supply mother pipe 104 connected to the steam-driven induced draft fan small unit Z. The secondary superheater outlet mother pipe 101 provides steam input for the entire standby high-pressure steam source, ensuring that the high-pressure standby steam source can be supplemented into the induced draft fan small steam turbine system when the conventional reheat steam pressure is insufficient.

[0050] It should be noted that there are two groups of secondary superheater outlet mother pipes 101, which are respectively connected to the two outlet headers on the A / B side, and the two groups of secondary superheater outlet mother pipes 101 are connected through the main pipeline 102.

[0051] Furthermore, the valve unit 200 includes a manual steam supply door 201 for manually closing when the high-pressure standby steam source is not needed, so as to isolate the standby steam source and prevent high-pressure steam from entering the low-pressure steam source pipeline due to misoperation; it can prevent the high-pressure steam source from accidentally entering the system when not necessary, causing problems such as excessive steam supply pressure, provides operational flexibility, and ensures that the system can operate safely and stably under various operating conditions.

[0052] Furthermore, the valve unit 200 includes a branch valve 202 to discharge residual moisture in the pipeline, ensuring that the steam enters the induced draft fan dryly, and avoiding the steam containing liquid moisture causing steam-water two-phase flow in the pipeline.

[0053] Furthermore, the valve unit 200 includes a steam supply electric shut-off valve 203 for controlling the on and off of the high-pressure steam source. The steam supply electric shut-off valve 203 allows the high-pressure steam source to be enabled or disabled through remote or automatic control. When the high-pressure standby steam source needs to be enabled under conditions such as low boiler load or shutdown purge, the electric shut-off valve opens to allow high-pressure steam to enter the system, and closes when it is not needed, ensuring that the switching of the high-pressure steam source is safer, more reliable and more convenient.

[0054] Furthermore, the valve unit 200 includes a steam supply pneumatic pressure regulating valve 204 for adjusting the steam supply pressure to the operating requirements of the induced draft fan small steam turbine. The steam supply pneumatic pressure regulating valve 204 can adjust the pressure of the high-pressure steam to the working requirements of the induced draft fan small steam turbine. Under normal circumstances, the steam supply pneumatic pressure regulating valve 204 will adjust the high pressure of the steam at the outlet of the secondary superheater above 9MPa to about 2-5MPa that the induced draft fan small steam turbine can accept. The stable operation of the induced draft fan is ensured by pressure regulation to avoid damage to the equipment caused by the high-pressure steam source.

[0055] The valve unit 200 includes a steam supply check valve 205 for preventing steam cross-flow between high-pressure and low-pressure steam sources, thereby ensuring the independence of the two steam sources in the steam supply system. When the high-pressure steam source is enabled, the steam supply check valve 205 prevents the low-pressure steam source from flowing back to the high-pressure steam source, thereby ensuring the isolation and independent operation of different steam sources, further ensuring the stability and safety of system operation.

[0056] The valve unit 200 includes a manual valve 206 after the steam supply check valve, which is used to isolate the high-pressure steam source when necessary to prevent it from being connected to the low-pressure steam source.

[0057] Further, the branch pipeline 103 includes two sets of drain branches 103a and a pressure relief branch 103b;

[0058] The two sets of drain branches 103a are respectively located between the steam supply manual door 201 and the steam supply electric stop door 203, and between the steam supply check valve 205 and the manual door 206 behind the steam supply check valve;

[0059] The branch valve 202 includes a drain electric door 202a connected to the two sets of drain branches 103a, a drain manual door 202b, and a safety door 202c connected to the pressure relief branch 103b;

[0060] The drain electric door 202a and the drain manual door 202b can be started before the high-pressure standby steam source is switched to discharge the residual moisture in the pipeline to ensure that the steam enters the induced draft fan dryer;

[0061] The safety door 202c is used to protect the small steam turbine of the induced draft fan. It can prevent the pipeline pressure after the pneumatic regulating valve from exceeding the rated steam inlet pressure of the small induced draft fan. The set value is 5.3MPa. When the pressure exceeds 5.3MPa, the safety door will operate to release the pressure to prevent the pipeline from overpressure operation.

[0062] In summary, through the reasonable configuration of the pipeline unit and the valve unit, the present embodiment realizes the flexible access and precise control of the high-pressure standby steam source under various working conditions. The synergy between the various components ensures the stable operation of the system, especially under working conditions such as deep peak regulation and shutdown purge. Through the effective supply of the standby steam source, the output of the small induced draft fan is improved, and the safety and reliability of the boiler system are guaranteed.

[0063] Example 3

[0064] Reference Figure 3 , which is the third embodiment of the present invention, and this embodiment provides a high-pressure steam source switching system, which includes the above-mentioned steam-driven induced draft fan device coupled with the steam source and the high-pressure steam source switching system, which can switch the low-pressure steam source to the high-pressure steam source and ensure the safe and smooth operation of the steam-driven induced draft fan.

[0065] The specific re-steam source pipeline unit 300 is provided with two groups of re-export headers connected to the two A / B sides respectively, which can be used to introduce the re-export steam of the boiler;

[0066] A recirculating pipeline valve unit 400, which is connected to the recirculating steam source pipeline unit 300 and can be used to adjust the steam source in the recirculating steam source pipeline unit 300;

[0067] A steam source pipeline unit 300 is connected to the pipeline unit 100;

[0068] The recirculating valve unit 400 is used to control the steam source in the recirculating valve unit 400 to assist in switching the steam source.

[0069] Furthermore, the steam source pipeline unit 300 includes two sets of steam pipes 301 and two sets of steam drain pipes 302 connected to the steam pipes 301;

[0070] The recirculation pipeline valve unit 400 includes a recirculation steam supply electric stop valve 401 arranged on the recirculation pipeline 301, a recirculation check valve 402 along the recirculation pipeline 301 close to the induced draft fan, and a recirculation drain electric door 403 and a recirculation drain manual door 404 arranged on the recirculation drain pipe 302.

[0071] Furthermore, the pipeline unit 100 is provided with a temperature measuring point T and a pressure measuring point P on which temperature sensors and pressure sensors can be placed. The temperature sensors and pressure sensors can be placed to monitor the steam temperature and pressure in the pipeline in real time to ensure that the steam parameters meet the operating requirements of the induced draft fan small steam turbine, and to send out an alarm signal or automatically control the pneumatic pressure regulating valve for adjustment when an abnormality is detected.

[0072] It should be noted that the first and second drain pipes 302 are respectively located in the direction away from the induced draft fan relative to the first and second steam supply electric stop valve 401, and in the direction close to the induced draft fan relative to the first and second check valve 402. The first and second pipes 301 are respectively connected to the first and second outlet headers on the A / B side, the main pipe 102, and the induced draft fan.

[0073] During use, when the unit requires deep peak regulation, start-up and shutdown and other special working conditions, it is necessary to switch the steam source of the induced draft fan to the high-pressure steam source, gradually open the steam supply manual door 201 on site, and open the drain electric door 202a and the drain manual door 202b in the drain branch 103a between the steam supply manual door 201 and the steam supply electric stop door 203, and then open the steam supply electric stop door 203, the steam supply pneumatic pressure regulating door 204, and the drain electric door 202a and the drain manual door 202b in the drain branch 103a between the steam supply check valve 205 and the manual door 206 behind the steam supply check valve, and drain and warm the corresponding pipelines section by section, during which the manual door 206 behind the steam supply check valve is kept closed. The steam supply pneumatic regulating valve 204 is in a closed state to better drain and warm the pipes. When the drain temperature behind the steam supply pneumatic regulating valve 204 is basically the same as the temperature of the steam supply main pipe of the induced draft fan, the steam supply pneumatic regulating valve 204 is closed, and the manual door 206 behind the steam supply check valve to the steam-driven induced draft fan small unit is manually opened. Then, the steam supply pneumatic regulating valve 204 is set to set the pressure of the high-pressure steam source steam supply main pipe between 2-5MPa, control the pressure of the high-pressure steam source pipeline within the normal range, and gradually close the drain electric door 202a in the two sets of drain branches 103a, keep the drain manual door 202b normally open, and when the high-pressure steam source is put into operation normally, close the steam supply electric stop door 401 again to complete the switching of high and low pressure steam sources of the induced draft fan small unit.

[0074] During the startup phase, the use of high-pressure steam source can advance steam supply to improve the thermal efficiency of the unit, so that the boiler reheat steam parameters need to be connected to 40% of the rated load to meet the small-unit output requirements of the induced draft fan.

[0075] After the boiler is normally connected to a load of more than 40%, the steam source of the induced draft fan is promptly switched back to the steam source supply of the first-stage reheater, and the steam source at the outlet of the second-stage superheater is kept in normal standby to realize the dual-path steam source coupling function.

[0076] The embodiments of the present disclosure may include the following beneficial effects: real-time monitoring of temperature and pressure sensors ensures that the pressure of the standby steam source can be accurately controlled within the range required by the small steam turbine of the induced draft fan, thereby avoiding steam pressure fluctuations or overpressure problems. Through the coordination between the valve unit 200 and the pipeline unit 100, it is possible to adaptively switch between the low-pressure steam source and the high-pressure steam source under special working conditions and adjust the valve unit 200 to meet the operating output requirements of the small induced draft fan, thereby adapting to the use requirements of the boiler in different states.

[0077] Furthermore, the following data were obtained by testing before and after the transformation:

[0078] Deep tuning process

[0079]

[0080] From the table above, we can see that when the unit's deep peak load is lower, the primary steam pressure gradually decreases, and the induced draft fan small unit regulating valve opening gradually increases to full open, which causes the primary steam source to be unable to meet the induced draft fan small unit output requirements. When the steam source is switched to the secondary steam supply, the induced draft fan small unit steam supply regulating valve remains at a normal opening, which can meet the normal induced draft fan small unit output requirements.

[0081] Boiler purge process after shutdown

[0082]

[0083] From the table above, we can see that after the boiler is shut down and before the purge, the boiler purge time is insufficient because the primary steam pressure cannot meet the output requirements of the induced draft fan. After the steam source is switched to the secondary steam supply, the normal purge time requirements of the boiler can be met.

[0084] The load section where the steam source during the unit startup process meets the output requirements of the small induced draft fan

[0085] Rated load segment ratio to be achieved Re-steam source 40％ Secondary steam source 20-30％

[0086] It can be seen from the above table that during the unit startup process, when the unit load reaches 20-30% of the rated load, the secondary steam pressure and temperature will meet the output requirements of the small induced draft fan, and the primary steam needs to be loaded to 40% of the rated load to meet the requirements. Therefore, when using a high-pressure steam source, the steam source of the small induced draft fan can be switched from the temporary machine to the steam source of this unit in advance, which can effectively improve the thermal efficiency of the unit.

[0087] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of performing the function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to several modifications still falling within the scope of the appended claims.

[0088] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0089] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0090] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A steam-driven induced draft fan device coupled with a steam source, characterized in that: include, Small steam-driven induced draft fan (Z); The pipeline unit (100) is used to introduce a high-pressure standby steam source; The valve unit (200) connected to the pipeline unit (100) can regulate and control the steam source in the pipeline unit (100).

2. The steam-driven induced draft fan device coupled with a steam source as claimed in claim 1, characterized in that: The pipeline unit (100) comprises a secondary superheater outlet main pipe (101), a main pipeline (102) connected to the secondary superheater outlet main pipe (101), a branch pipeline (103) connected to the main pipeline to assist the normal operation of the main pipeline (102), and a steam-driven induced draft fan small unit steam supply main pipe (104) connected to the steam-driven induced draft fan small unit (Z).

3. The steam-driven induced draft fan device coupled with a steam source as claimed in claim 2, characterized in that: The valve unit (200) comprises a manual steam supply door (201) for manually closing when the high-pressure standby steam source is not needed, so as to isolate the standby steam source and prevent high-pressure steam from entering the low-pressure steam source pipeline due to misoperation.

4. The steam-driven induced draft fan device coupled to a steam source as claimed in claim 3, characterized in that: The valve unit (200) comprises a branch valve (202) for discharging residual moisture in the pipeline, thereby ensuring that the steam enters the induced draft fan in a dry state.

5. The steam-driven induced draft fan device coupled to a steam source as claimed in claim 4, characterized in that: The valve unit (200) comprises a steam supply electric stop valve (203) for controlling the on and off of the high-pressure steam source.

6. The steam-driven induced draft fan device coupled to a steam source as claimed in claim 5, characterized in that: The valve unit (200) comprises a steam supply pneumatic pressure regulating valve (204) for adjusting the steam supply pressure to the operating requirements of the induced draft fan small steam turbine; The valve unit (200) comprises a steam supply check valve (205) for preventing steam cross-flow between high-pressure and low-pressure steam sources; The valve unit (200) comprises a manual valve (206) after the steam supply check valve, which is used to isolate the high-pressure steam source when necessary to prevent it from being connected to the low-pressure steam source.

7. The steam-driven induced draft fan device coupled to a steam source as claimed in claim 6, characterized in that: The branch pipeline (103) includes two groups of drain branches (103a) and a pressure relief branch (103b); The two groups of drain branches (103a) are respectively located between the steam supply manual door (201) and the steam supply electric stop door (203), and between the steam supply check valve (205) and the steam supply check valve rear manual door (206); The branch valve (202) comprises a drain electric door (202a) connected to the two sets of drain branches (103a), a drain manual door (202b), and a safety door (202c) connected to the pressure relief branch (103b); The drain electric door (202a) and the drain manual door (202b) can be started before the high-pressure standby steam source is switched to discharge the residual moisture in the pipeline to ensure that the steam enters the induced draft fan in a dry state; The safety door (202c) is used to protect the small steam turbine of the induced draft fan.

8. A high-pressure steam source switching system, characterized in that: A steam-driven induced draft fan device coupled to a steam source as claimed in any one of claims 1 to 7; and A steam source pipeline unit (300) is provided with two groups of steam outlet headers connected to the two A / B sides respectively, and can be used to introduce steam from the boiler outlet; A recirculating pipeline valve unit (400), which is connected to the recirculating steam source pipeline unit (300) and can be used to adjust the steam source in the recirculating steam source pipeline unit (300); The steam source pipeline unit (300) is connected to the pipeline unit (100); The recirculating valve unit (400) is used to control the steam source in the recirculating valve unit (400) to assist in achieving steam source switching.

9. The high pressure steam source switching system according to claim 8, characterized in that: The one-way steam source pipeline unit (300) comprises two groups of one-way pipelines (301) and two groups of one-way drain pipes (302) connected to the one-way pipelines (301); The recirculation pipeline valve unit (400) comprises a recirculation steam supply electric stop valve (401) arranged on the recirculation pipeline (301), a recirculation check valve (402) along the recirculation pipeline (301) close to the induced draft fan, and a recirculation drain electric door (403) and a recirculation drain manual door (404) arranged on the recirculation drain pipe (302).

10. The high pressure steam source switching system according to claim 9, characterized in that: The pipeline unit (100) is provided with a temperature measuring point (T) and a pressure measuring point (P) where a temperature sensor and a pressure sensor can be placed. The temperature sensor and the pressure sensor can be placed to monitor the steam temperature and pressure in the pipeline in real time to ensure that the steam parameters meet the operation requirements of the induced draft fan small steam turbine, and to send out an alarm signal or automatically control the pneumatic pressure regulating valve for adjustment when an abnormality is detected.

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