Heater starting exhaust detection device

Abstract

The utility model relates to the technical field of power plant detection, in particular to a heater starting exhaust detection device. Comprising a turbine high-pressure cylinder connected with a boiler; a steam inlet of the heater is connected with the steam turbine high-pressure cylinder through a steam extraction pipeline; one end of the starting exhaust pipeline is connected with an exhaust port of the heater, and the other end is connected with atmosphere; the temperature / humidity detection device is arranged on the starting exhaust pipeline; the exhaust valve is arranged on the starting exhaust pipeline; the signal input end of the DCS control device is connected with the signal output end of the temperature / humidity detection device, and the signal output end of the DCS control device is connected with the signal output end of the exhaust valve. Remote automatic monitoring and control of the heater starting exhaust process are achieved, and the problems that remote automatic control of heater starting exhaust cannot be achieved at the present stage, the labor intensity of operators on duty is large, and a unit cannot complete one-key starting and stopping are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power plant detection, in particular to a heater start-up exhaust detection device. BACKGROUND

[0002] In the design of thermal power plants, the steam turbine is provided with multiple stages of non-regulated extraction steam to supply each stage of heater, and during the start-up of the unit, the steam is sequentially supplied to the corresponding heater from high pressure to low pressure according to the sliding parameter operation mode, and each stage of heater is provided with a start-up exhaust pipeline to the atmosphere. The purpose of the start-up exhaust is to gradually exhaust the air in the heater through the imported steam during the start-up of the unit until the requirement is met, so that the steam in the heater shell and the water medium in the internal pipeline of the heater are fully heat exchanged. During the start-up of the unit, the amount of steam extracted to each stage of heater is controlled, the start-up exhaust valve of the heater is opened by the auxiliary duty personnel on site, and it is observed on site whether the air in the heater is exhausted to meet the requirements, and the exhaust valve is closed after the air in the heater is exhausted to meet the requirements (the exhausted medium changes from air to water vapor), which requires a certain amount of time and manual operation by the on-site personnel. The number of heaters of a large unit is 7-12 and is scattered, and in the existing scheme, the auxiliary duty personnel need to manually exhaust one by one on site during the start-up stage, which requires a long on-site observation and waiting time and a large amount of manpower, and cannot meet the requirements of one-key start-stop control of the unit. SUMMARY

[0003] Therefore, the embodiments of the present application provide a heater start-up exhaust detection device to solve the problems that the start-up exhaust of the heater cannot be remotely and automatically controlled, the labor intensity of the operation duty personnel is large, and the unit cannot complete one-key start-stop.

[0004] The first aspect of the embodiments of the present application provides a heater start-up exhaust detection device, which comprises:

[0005] A steam turbine high-pressure cylinder connected to a boiler;

[0006] At least one heater, an inlet of the heater being connected to the steam turbine high-pressure cylinder through an extraction pipeline;

[0007] A start-up exhaust pipeline, one end of the start-up exhaust pipeline being connected to an exhaust port of the heater, and the other end of the start-up exhaust pipeline being connected to the atmosphere;

[0008] A temperature / humidity detection device arranged on the start-up exhaust pipeline;

[0009] An exhaust valve arranged on the start-up exhaust pipeline;

[0010] A DCS control device, a signal input end of the DCS control device being connected to a signal output end of the temperature / humidity detection device, and a signal output end of the DCS control device being connected to a signal output end of the exhaust valve.

[0011] In one embodiment, the steam extraction pipeline is provided with a steam extraction valve, and the signal output end of the DCS control device is further connected with the signal input end of the steam extraction valve.

[0012] The DCS control device is configured to control the opening and closing of the exhaust valve and the partial opening or full opening of the steam extraction valve according to the measurement value of the temperature / humidity detection device.

[0013] In one embodiment, the heater comprises a first heater and a second heater, the first heater is connected with the first steam outlet of the high-pressure cylinder of the steam turbine through a first-stage steam extraction pipeline, and the second heater is connected with the second steam outlet of the exhaust steam of the high-pressure cylinder of the steam turbine through a second-stage steam extraction pipeline.

[0014] In one embodiment, the steam extraction valve is formed by a combination of an electric valve and a check valve.

[0015] In one embodiment, a high-pressure cylinder exhaust check valve is arranged between the high-pressure cylinder of the steam turbine and the boiler.

[0016] In one embodiment, the temperature / humidity detection device is located downstream of the exhaust valve.

[0017] In one embodiment, the temperature / humidity detection device is a thermal resistance temperature measurement element or a steam humidity meter.

[0018] The embodiment of the present application connects a boiler with a high-pressure cylinder of a steam turbine, at least one heater, a start-up exhaust pipeline, a temperature / humidity detection device, an exhaust valve, and a DCS control device. The steam inlet of the heater is connected with the high-pressure cylinder of the steam turbine through a steam extraction pipeline. One end of the start-up exhaust pipeline is connected with the exhaust port of the heater, and the other end is connected with the atmosphere. The temperature / humidity detection device is arranged on the start-up exhaust pipeline. The exhaust valve is arranged on the start-up exhaust pipeline. The signal input end of the DCS control device is connected with the signal output end of the temperature / humidity detection device, and the signal output end of the DCS control device is connected with the signal output end of the exhaust valve. The DCS can detect the temperature or humidity of the medium discharged by the heater into the atmosphere through the temperature / humidity detection device to determine whether the air in the heater has been discharged to meet the requirements, and trigger the control of the exhaust valve and the steam extraction valve. The embodiment realizes remote automatic monitoring and control of the start-up exhaust process of the heater, solves the problem that the start-up exhaust of the heater cannot be remotely and automatically controlled at the present stage, and solves the problem that the operating staff has a large labor intensity and the unit cannot complete one-key start and stop. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without any creative effort.

[0020] Figure 1 Figure 1 is a structural schematic diagram of a heater start-up exhaust detection device provided by an embodiment of the present application.

[0021] Figure 1 is a structural schematic diagram of a heater start-up exhaust detection device provided by an embodiment of the present application. Specific implementation

[0022] In the following description, for the purpose of explanation and not limitation, specific details are set forth, such as particular system configurations, techniques, etc., in order to provide a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application can be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

[0023] It should also be understood that the term "and / or" as used herein refers to any combination of associated terms, including all possible combinations, and includes one or more of the associated terms.

[0024] In addition, in the description of the present application and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0025] In the present application, the reference "one embodiment" or "some embodiments" means that the specific features, structures or characteristics described in connection with the embodiment are included in one or more embodiments of the present application. Therefore, the statements "in one embodiment", "in some embodiments", "in other some embodiments", "in other some embodiments" and the like appearing in the present description are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized. The terms "include", "contain", "have" and their variants mean "include but not limited to", unless otherwise specifically emphasized.

[0026] As Figure 1 shown, the embodiment of the application provides a heater start-up exhaust detection device, comprising:

[0027] A high-pressure cylinder 1 of a steam turbine is connected to a boiler 11.

[0028] At least one heater is connected to the high-pressure cylinder 1 of the steam turbine through a steam extraction pipeline 10.

[0029] A start-up exhaust pipeline 12 is connected to an exhaust port of the heater at one end and to the atmosphere at the other end.

[0030] A temperature / humidity detection device 9 is arranged on the start-up exhaust pipeline 12.

[0031] An exhaust valve is arranged on the start-up exhaust pipeline 12.

[0032] A DCS control device is connected to a signal output end of the temperature / humidity detection device 9 and to a signal output end of the exhaust valve.

[0033] In application, each stage of steam extraction of the steam turbine provides steam to each heater, the DCS controls the opening degree of the steam extraction motorized door to maintain a certain steam flow to supply to the corresponding heater, the DCS synchronously opens the heater start-up exhaust motorized valve, as the amount of steam flowing into the heater increases, the air in the heater is gradually driven to the atmosphere, the DCS determines that the air in the heater has been exhausted to meet the requirements by detecting the temperature or humidity of the medium discharged by the heater to the atmosphere when the temperature or humidity of the discharged medium rises to a certain value (the temperature set value is 15℃ higher than the ambient temperature, and the humidity is 20 RH% higher than the ambient humidity), at this time, the DCS automatically closes the heater start-up exhaust motorized valve and places the steam extraction motorized valve in the fully open position.

[0034] In application, the DCS control system realizes one step of the uninterrupted self-starting and stopping control of the unit.

[0035] In application, the heater start-up exhaust is to the atmosphere, the heater start-up exhaust motorized valve is closed when the air in the heater is exhausted to meet the requirements, and the corresponding steam extraction motorized door is fully opened.

[0036] The embodiment of the application is characterized in that the turbine high-pressure cylinder is connected with a boiler; at least one heater is connected with the turbine high-pressure cylinder through a steam extraction pipeline; a starting exhaust pipeline is connected with an exhaust port of the heater at one end and connected with the atmosphere at the other end; a temperature / humidity detection device is arranged on the starting exhaust pipeline; an exhaust valve is arranged on the starting exhaust pipeline; and a DCS control device is connected with a signal output end of the temperature / humidity detection device and connected with a signal output end of the exhaust valve. The DCS can detect the temperature or humidity of the medium discharged by the heater into the atmosphere through the temperature / humidity detection device, determine whether the air in the heater has been discharged to meet the requirements, and trigger the control of the exhaust valve and the steam extraction valve, so as to realize the remote automatic monitoring and control of the starting exhaust process of the heater, solve the problem that the starting exhaust of the heater cannot be remotely and automatically controlled at the present stage, and solve the problem that the operation staff has a high labor intensity and the unit cannot complete one-key start and stop.

[0037] In one embodiment, a steam extraction valve is arranged on the steam extraction pipeline 10, and a signal output end of the DCS control device is further connected with a signal input end of the steam extraction valve.

[0038] The DCS control device is configured to control the opening and closing of the exhaust valve and the local opening or full opening of the steam extraction valve according to the measurement value of the temperature / humidity detection device 9, wherein the local opening refers to opening the steam extraction valve to a position near the intermediate opening degree.

[0039] In application, the steam extraction valve includes a first-stage steam extraction electric valve and a check valve 5 and a second-stage steam extraction electric valve and a check valve 6. The exhaust valve includes a first high-pressure heater starting exhaust electric valve 7 and a second high-pressure heater starting exhaust electric valve 8.

[0040] The embodiment of the application optimizes the steam flow distribution through the cooperative control strategy of the steam extraction valve and the exhaust valve, avoids excessive steam waste while ensuring that the air in the heater is fully discharged, and balances the contradiction between the steam supply stability and the exhaust efficiency during the start-up of the unit through the dynamic adjustment of the opening degree of the steam extraction electric valve.

[0041] In one embodiment, the heater includes a first heater 2 and a second heater 3, the first heater 2 is connected with a first steam outlet of the turbine high-pressure cylinder 1 through a first-stage steam extraction pipeline 10, and the second heater 3 is connected with a second steam outlet of the turbine high-pressure cylinder 1 through a second-stage steam extraction pipeline 10.

[0042] The embodiment of the application is designed in accordance with the operation characteristics of the multi-stage non-regulated steam extraction of the thermal power plant through the hierarchical steam extraction pipeline, avoids the interference of the high-pressure steam on the exhaust system of the low-pressure heater by independently controlling the exhaust of the heaters of different pressure grades, and meets the process requirements of the step-by-step steam supply during the sliding parameter start-up.

[0043] In one embodiment, the extraction valve is formed by a combination of an electric valve and a check valve.

[0044] The combination of the electric valve and the check valve in the embodiments of the present application can achieve remote and accurate control and prevent the medium in the heater from flowing back to the steam turbine to damage the turbine blades. Compared with the traditional single valve structure, the valve jamming risk and the medium backflow risk can be solved synchronously, and the system reliability is improved.

[0045] In one embodiment, a high-pressure cylinder exhaust check valve 4 is arranged between the high-pressure cylinder 1 of the steam turbine and the boiler 11.

[0046] In one embodiment, the exhaust valve is arranged upstream of the temperature / humidity detection device 9.

[0047] The arrangement downstream of the detection device in the embodiments of the present application can accurately capture the change in the medium state after the steam displaces the air, and avoid the misjudgment caused by the fluid disturbance in the valve opening and closing moment. At the same time, the layout reduces the direct impact of high-temperature steam on the sensor, and prolongs the service life of the detection device.

[0048] In one embodiment, the temperature / humidity detection device 9 is a thermal resistance temperature measurement element or a steam humidity meter.

[0049] In application, the temperature detection device adopts a thermal resistance temperature measurement element with excellent performance, and the humidity detection device adopts a 4-20 mADC remote steam humidity meter with excellent performance.

[0050] The working principle of the device is as follows:

[0051] The steam discharged from the high-pressure cylinder 1 of the steam turbine flows back to the boiler after passing through the high-pressure cylinder exhaust check valve 4, and is reheated. The steam discharged from the high-pressure cylinder 1 of the steam turbine is simultaneously divided into a part that passes through the second extraction electric valve and the check valve 6 to serve as the heating steam of the second heater 3. The steam extracted from the high-pressure cylinder passes through the first extraction electric valve and the check valve 5 to serve as the working steam source of the first heater 2. During the startup stage of the unit, the electric valves on the extraction pipelines are controlled to a certain opening degree, and when the steam enters the heaters in turn, the first heater 2 startup exhaust electric valve 7 and the second high-pressure heater startup exhaust electric valve 8 are opened synchronously. The temperature / humidity detection device 9 is arranged on the pipeline after the high-pressure heater startup exhaust electric valve. The temperature / humidity detection device 9 sends the detection signal to the DCS control system. When the medium temperature or humidity is detected to rise to a certain value, the DCS control system determines that the air in the heater has been exhausted to meet the requirements. At this time, the DCS control system automatically closes the exhaust electric valve of the corresponding heater, and automatically sets the extraction electric valve on the corresponding extraction pipeline to the fully open state.

[0052] The above examples are only used to illustrate the technical solutions of the present application, but not limit the same; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can be modified, or some technical features can be replaced by equivalent ones; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A heater start-up exhaust gas detection device characterized by comprising: The steam turbine high-pressure cylinder (1) is connected with the boiler (11); At least one heater, the steam inlet of which is connected with the steam turbine high-pressure cylinder (1) through the extraction pipe (10); A starting exhaust pipe (12) is connected at one end with the exhaust outlet of the heater and at the other end with the atmosphere; A temperature / humidity detection device (9) is arranged on the starting exhaust pipe (12); An exhaust valve is arranged on the starting exhaust pipe (12); A DCS control device is connected at the signal input end with the signal output end of the temperature / humidity detection device (9) and at the signal output end with the signal output end of the exhaust valve. An extraction valve is arranged on the extraction pipe (10), and the signal output end of the DCS control device is further connected with the signal input end of the extraction valve; 2. The heater start-up exhaust detection device of claim 1, wherein The DCS control device is configured to control the opening and closing of the exhaust valve and the partial opening or full opening of the extraction valve according to the measurement value of the temperature / humidity detection device (9). The heater comprises a first heater (2) and a second heater (3), the first heater (2) is connected with the first steam outlet of the steam turbine high-pressure cylinder (1) through the first extraction pipe (10), and the second heater (3) is connected with the second steam outlet of the steam turbine high-pressure cylinder (1) through the second extraction pipe (10).

3. The heater start-up exhaust detection device of claim 1, wherein The extraction valve is formed by the combination of an electric valve and a check valve.

4. The heater start-up exhaust detection device of claim 2, wherein A high-pressure cylinder exhaust check valve (4) is arranged between the steam turbine high-pressure cylinder (1) and the boiler (11).

5. The heater start-up exhaust detection device of claim 1, wherein The temperature / humidity detection device (9) is located downstream of the exhaust valve.

6. The heater start-up exhaust detection device of claim 1, wherein The temperature / humidity detection device (9) is a thermal resistance temperature measurement element or a steam humidity meter.

7. The heater start-up exhaust detection device of claim 1, wherein ​

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