High-pressure heater drain pipeline flushing device and method and thermal power generation system
By closing some valves in the high-pressure heater drainage pipeline and opening the auxiliary pipeline for hot flushing of the high-pressure heater, the problem of the inability to flush the drainage pipeline in traditional technology is solved, and the living water state of the entire section of the pipeline is realized, meeting the standard water supply standards.
Patent Information
- Application Number
- CN202411325794.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-23
- Publication Date
- 2024-12-20
AI Technical Summary
In the traditional high-pressure heater water drain pipeline flushing method, the normal water drain pipeline between the high-pressure heater and the deaerator cannot be flushed, resulting in the accumulation of sediment in the pipeline and the failure to meet the relevant standard water supply standards.
In the early stage of the start of the thermal power plant, by closing the second valve on the jeopardized pipeline and the third valve on the normal pipeline, opening the first valve and the fourth valve, using the normal drainage pipeline to perform hot flushing of the high-pressure heater, and setting up auxiliary pipelines to achieve the realization of Flushing of all pipes.
The stagnant water in the normal hydrophobic pipe between the high-pressure heater and the deaerator is turned into living water, solving the problem of rinsing dead corners in traditional technology and ensuring that the entire hydrophobic section meets the relevant standard water supply standards.
Smart Images
Figure CN119163948A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of thermal power plant startup, and in particular relates to a high-pressure heater drain pipeline flushing device and method and a thermal power generation system. Background Art
[0002] At the initial start-up of a thermal power plant, hot flushing of the high-pressure heater is required. The purpose of the flushing is to clean the normal drain pipes of the high-pressure heater until the quality reaches the relevant water supply standards, and then enter the deaerator for recovery.
[0003] The inventors found that in the traditional scheme, a normal drain pipeline and valve, as well as an emergency drain pipeline and valve are set on the last high-pressure heater. When flushing, the valve on the normal drain pipeline between the high-pressure heater and the deaerator is closed, and the valve on the emergency drain pipeline of the high-pressure heater is opened to drain water; however, in the traditional scheme, each time the flushing process is performed, the normal drain pipeline between the high-pressure heater and the deaerator is dead water, and this pipe section cannot be flushed. Long-term accumulation will cause the normal drain pipeline between the high-pressure heater and the deaerator to fail to meet the relevant standardized water supply standards. Summary of the invention
[0004] In order to solve the above-mentioned problems, the present invention proposes a high-pressure heater drain pipeline flushing device, method and thermal power generation system. At the initial start-up of the thermal power plant, when the preset conditions are met, the second valve on the endangered pipeline and the third valve on the normal pipeline are closed, the first valve and the fourth valve are opened, and the high-pressure heater is hot-flushed through the normal drain pipeline, so that the dead water in the normal drain pipeline between the high-pressure heater and the deaerator during the flushing stage is converted into living water that can be used for pipeline flushing, which solves the problem that in traditional technology, only the endangered pipeline is used for flushing, resulting in long-term accumulation of sediments in the normal drain pipeline between the high-pressure heater and the deaerator, and ensures that the entire normal drain section can meet the purpose of relevant standardized water supply standards.
[0005] In order to achieve the above-mentioned object, in a first aspect, the present invention provides a high-pressure heater drain pipe flushing device, which adopts the following technical solution:
[0006] A high-pressure heater drain pipe flushing device comprises a plurality of interconnected high-pressure heaters, a drain expansion tank and a deaerator;
[0007] The drain expansion tank is connected to the deaerator; one of the high-pressure heaters is connected to the deaerator through a normal drain pipeline; at least one high-pressure heater is connected to the drain expansion tank through a dangerous drain pipeline;
[0008] The normal drain pipe is provided with a first valve and a third valve at one end close to the deaerator, and the third valve is located between the first valve and the deaerator; the endangered drain pipe is provided with a second valve; an auxiliary pipe is provided between the normal drain pipe and the drain expansion tank, the inlet of the auxiliary pipe is located between the first valve and the third valve, and the auxiliary pipe is provided with a fourth valve;
[0009] At the initial start-up of the thermal power plant, when the preset conditions are met, the second valve and the third valve are closed, the first valve and the fourth valve are opened, and the high-pressure heater is hot-flushed through the normal drain pipe.
[0010] Furthermore, the deaerator is connected to a first high-pressure heater, a second high-pressure heater and a third high-pressure heater which are interconnected through the normal drain pipe; a fifth valve is provided on the normal drain pipe between the first high-pressure heater and the second high-pressure heater, a sixth valve is provided on the normal drain pipe between the second high-pressure heater and the third high-pressure heater, and the third high-pressure heater is connected to the deaerator through the normal drain pipe.
[0011] Furthermore, the first high-pressure heater, the second high-pressure heater and the third high-pressure heater are connected to the hydrophobic expansion tank through a hazardous hydrophobic pipeline and a second valve, respectively.
[0012] Furthermore, a seventh valve is provided on the pipeline between the hydrophobic expansion tank and the deaerator.
[0013] Furthermore, a pressure-release jellyfish pipe is connected to the pipeline between the seventh valve and the deaerator through the pipeline and the eighth valve.
[0014] Furthermore, the pipeline between the seventh valve and the hydrophobic expansion tank is connected to the overflow port of the deaerator through the pipeline and the ninth valve.
[0015] Furthermore, the deaerator is provided with a startup exhaust port and an operation exhaust port.
[0016] In order to achieve the above-mentioned purpose, in a second aspect, the present invention also provides a method for flushing a high-pressure heater drain pipe, which adopts the following technical solution:
[0017] A method for flushing a high-pressure heater drain pipe adopts the high-pressure heater drain pipe flushing device as described in the first aspect, comprising: at the initial start-up of a thermal power plant, when preset conditions are met, closing the second valve and the third valve, opening the first valve and the fourth valve, and hot flushing the high-pressure heater through the normal drain pipe.
[0018] Further, when the pressures on the water inlet pipes of the first high-pressure heater, the second high-pressure heater and the third high-pressure heater are respectively lower than the corresponding preset values, the second valve and the third valve are closed, the first valve and the fourth valve are opened, and the high-pressure heater is hot-flushed through the normal drain pipe; otherwise, the high-pressure heater is hot-flushed through the endangered drain pipe;
[0019] When the pressure on the water inlet pipe of the first high-pressure heater is higher than the preset first threshold value, the fifth valve is closed, and the first high-pressure heater is hot-flushed through the hazardous drain pipe on the first high-pressure heater; otherwise, the fifth valve is opened, and the second valve on the hazardous drain pipe between the first high-pressure heater and the deaerator is closed;
[0020] When the pressure on the water inlet pipe of the second high-pressure heater is higher than the preset second threshold value, the sixth valve is closed and the second high-pressure heater and the first high-pressure heater are hot-flushed through the hazardous drain pipe on the second high-pressure heater; otherwise, the sixth valve is opened and the second valve on the hazardous drain pipe between the second high-pressure heater and the deaerator is closed.
[0021] In order to achieve the above-mentioned purpose, in a third aspect, the present invention further provides a thermal power generation system, which adopts the following technical solution:
[0022] A thermal power generation system adopts the high-pressure heater drain pipe flushing device as described in the first aspect.
[0023] Compared with the prior art, the present invention has the following beneficial effects:
[0024] In the present invention, an auxiliary pipeline is arranged between the normal drain pipe and the drain expansion tank, the inlet of the auxiliary pipeline is located between the first valve and the third valve, and the fourth valve is arranged on the auxiliary pipeline; at the initial start-up of the thermal power plant, when the preset conditions are met, the second valve on the endangered pipeline and the third valve on the normal pipeline are closed, the first valve and the fourth valve are opened, and the high-pressure heater is hot-flushed through the normal drain pipeline, so that the dead water in the normal drain pipeline between the high-pressure heater and the deaerator during the flushing stage is converted into live water that can be used for pipeline flushing, which solves the problem that in the traditional technology, only the endangered pipeline is used for flushing, resulting in long-term accumulation of sediments in the normal drain pipeline between the high-pressure heater and the deaerator, and ensures that the whole section of the normal drain can meet the purpose of relevant standardized water supply standards. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The drawings in the specification that constitute a part of this embodiment are used to provide a further understanding of this embodiment. The schematic embodiments of this embodiment and their descriptions are used to explain this embodiment and do not constitute improper limitations on this embodiment.
[0026] Figure 1It is a schematic diagram of a conventional flushing device;
[0027] Figure 2 Schematic diagram of a flushing device according to an embodiment of the present invention. DETAILED DESCRIPTION
[0028] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.
[0029] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.
[0030] Embodiment 1:
[0031] At the initial start-up of a thermal power plant, the high-pressure heater needs to be hot-flushed. The purpose of the flushing is to clean the normal drain pipes of the high-pressure heater until the quality reaches the relevant standard water supply standards, and then enter the deaerator for recovery. Figure 1 As shown, in the traditional design, the third high-pressure heater is provided with normal drain and emergency drain. Under this design limitation, the original flushing method is to close the normal drain pipeline valve from the third high-pressure heater to the deaerator, and open the emergency drain valve of the third high-pressure heater as the end of the system for drainage.
[0032] like Figure 1 and Figure 2 As shown, in the traditional design, the water circuit for system flushing is the high-pressure heater drain from the first high-pressure heater, drained to the second high-pressure heater through the fifth valve, the condensate of the second high-pressure heater is drained to the third high-pressure heater through the sixth valve, and the third high-pressure heater is drained to the drain expansion tank through the hazardous drain pipe and the second valve to achieve the flushing effect.
[0033] However, in the traditional design, the high-pressure heater is set with normal drain and emergency drain to meet the needs of normal operation, but there are defects when the unit is hot-flushing. Specifically, under the limitations of the traditional design, the flushing method is to close the valve of the normal drain pipeline from the third high-pressure heater to the deaerator, and open the emergency drain valve of the third high-pressure heater as the end of the system for drainage. In this method, the normal drain pipeline between the third high-pressure heater and the deaerator is dead water, and this pipe section cannot be flushed, resulting in poor quality water in this pipe section entering the deaerator, affecting the safety of the overall system.
[0034] In response to the above problems, the present embodiment provides a high-pressure heater drain pipe flushing device, at the end of the normal drain pipe between the third high-pressure heater and the deaerator, an auxiliary pipe is added in front of the third valve, and the auxiliary pipe can be used as the tail for drainage during hot flushing; the addition of the auxiliary pipe and the use of the auxiliary pipe for hot flushing can eliminate flushing dead corners in the system and increase flushing efficiency, which has huge advantages in economy, practicality and scientificity.
[0035] like Figure 2 As shown, a high-pressure heater drain pipe flushing device provided in this embodiment includes a plurality of interconnected high-pressure heaters, a drain expansion tank and a deaerator;
[0036] The drain expansion tank is connected to the deaerator; one of the high-pressure heaters is connected to the deaerator through a normal drain pipeline; at least one high-pressure heater is connected to the drain expansion tank through a dangerous drain pipeline;
[0037] A first valve and a third valve are provided on the normal drain pipe at one end close to the deaerator, and the third valve is located between the first valve and the deaerator; a second valve is provided on the endangered drain pipe; an auxiliary pipe is provided between the normal drain pipe and the drain expansion tank, the inlet of the auxiliary pipe is located between the first valve and the third valve, and a fourth valve is provided on the auxiliary pipe.
[0038] Specifically, at the initial start-up of the thermal power plant, when the preset conditions are met, the second valve and the third valve are closed, the first valve and the fourth valve are opened, and the high-pressure heater is hot-flushed through the normal drain pipe; the high-pressure heater is hot-flushed through the normal drain pipe, so that the dead water in the normal drain pipe between the high-pressure heater and the deaerator during the flushing stage is transformed into living water that can be used for pipe flushing, which solves the problem that flushing in traditional technology only uses dangerous pipes, resulting in long-term accumulation of sediments in the normal drain pipe between the high-pressure heater and the deaerator, and ensures that the entire normal drain section can meet the purpose of relevant standardized water supply standards.
[0039] In some embodiments, at the initial start-up of a thermal power plant, auxiliary pipelines can be independently utilized for hot flushing, and the switching between flushing and normal drainage conditions can be achieved by switching the third valve and the fourth valve on and off. At this time, not only can the problem that normal drainage pipelines cannot be flushed be solved, but also the efficiency of hot flushing can be improved, and the cost of hot flushing that endangers pipeline utilization and maintenance can be reduced.
[0040] In other embodiments, at the initial start-up of a thermal power plant, it is possible to switch between using auxiliary pipelines for hot flushing and using hazardous drain pipelines for hot flushing according to actual conditions, thereby avoiding the impact on normal drain pipelines due to problems such as high pressure, and solving the problem that normal drain pipelines cannot be flushed.
[0041] Specifically, when the pressures on the water inlet pipes of the multiple high-pressure heaters are respectively lower than the corresponding preset values, the second valve and the third valve are closed, the first valve and the fourth valve are opened, and the high-pressure heater is hot-flushed through the normal drain pipe. At this time, the problem that the normal drain pipe cannot be flushed can be solved. Otherwise, hot-flushing the high-pressure heater through the endangered drain pipe can avoid the impact on the normal drain pipe caused by high pressure and other problems.
[0042] The high-pressure heater, hydrophobic expansion vessel, deaerator, etc. in this embodiment can all be realized by conventional equipment and will not be described in detail here.
[0043] Optionally, the deaerator is connected to a first high-pressure heater, a second high-pressure heater and a third high-pressure heater which are interconnected through the normal drain pipe; a fifth valve is provided on the normal drain pipe between the first high-pressure heater and the second high-pressure heater, a sixth valve is provided on the normal drain pipe between the second high-pressure heater and the third high-pressure heater, and the third high-pressure heater is connected to the deaerator through the normal drain pipe.
[0044] Specifically, when the pressure on the water inlet pipe of the first high-pressure heater is higher than the preset first threshold, the fifth valve is closed, and the first high-pressure heater is hot-flushed through the endangered drain pipe on the first high-pressure heater to avoid excessive pressure and the impact on the subsequent pipes; otherwise, the fifth valve is opened and the second valve on the endangered drain pipe between the first high-pressure heater and the deaerator is closed;
[0045] When the pressure on the water inlet pipe of the second high-pressure heater is higher than the preset second threshold value, the sixth valve is closed, and the second high-pressure heater and the first high-pressure heater are hot-flushed through the hazardous drain pipe on the second high-pressure heater to avoid excessive pressure and the impact on the subsequent pipes; otherwise, the sixth valve is opened and the second valve on the hazardous drain pipe between the second high-pressure heater and the deaerator is closed.
[0046] Optionally, the first high-pressure heater, the second high-pressure heater and the third high-pressure heater are connected to the hydrophobic expansion tank through a hazardous hydrophobic pipeline and a second valve, respectively.
[0047] Specifically, when the water pressure is too high or in some other situations, an independent hazardous drain pipe and a second valve can be used to perform independent hot flushing of one or several high-pressure heaters to reduce the impact of subsequent pipeline overpressure work.
[0048] Optionally, a seventh valve is provided on the pipeline between the hydrophobic expansion tank and the deaerator. A pressure discharge main pipe is connected to the pipeline between the seventh valve and the deaerator through a pipeline and an eighth valve. The pipeline between the seventh valve and the hydrophobic expansion tank is connected to the overflow port of the deaerator through a pipeline and a ninth valve. A startup exhaust port and an operating exhaust port are provided on the deaerator; a tenth valve is provided on the pipeline of the startup exhaust port, and an eleventh valve is provided on the pipeline of the operating exhaust port. Specifically, the settings of the seventh valve, the eighth valve, the pressure discharge main pipe, the ninth valve, the startup exhaust port and the operating exhaust port can meet the flexible switching between multiple working conditions and ensure the operating stability of the overall system.
[0049] Optionally, in some embodiments, the first valve, the second valve, the fifth valve, the sixth valve, the seventh valve, the eighth valve, the ninth valve, the tenth valve and the eleventh valve are electromagnetic control valves connected to a controller; the water inlet pipes, the water outlet pipes of the first high-pressure electric heater, the second high-pressure electric heater and the third high-pressure electric heater, and the corresponding pipes of other equipment are provided with water pressure sensors, temperature sensors, etc., and each sensor is connected to the controller; the controller has the function of data processing and generating control instructions for each valve; the third valve and the fourth valve can be manual valves. Of course, in some other embodiments, the third valve and the fourth valve can also be electromagnetic control valves connected to the controller.
[0050] Through this embodiment, the dead corner of the hot flushing of the high-pressure heater drain system is eliminated, so that the entire high-pressure heater drain system is flushed with a large flow rate, which is conducive to the qualified drain quality. It effectively prevents the poor quality water from the third high-pressure heater to the deaerator pipe section from entering the deaerator, ensuring the safety of the overall system.
[0051] Embodiment 2:
[0052] The present embodiment provides a method for flushing a high-pressure heater drain pipe, which adopts the high-pressure heater drain pipe flushing device as described in Example 1, including: at the initial start-up of the thermal power plant, when the preset conditions are met, closing the second valve and the third valve, opening the first valve and the fourth valve, and hot flushing the high-pressure heater through the normal drain pipe.
[0053] Further, when the pressures on the water inlet pipes of the first high-pressure heater, the second high-pressure heater and the third high-pressure heater are respectively lower than the corresponding preset values, the second valve and the third valve are closed, the first valve and the fourth valve are opened, and the high-pressure heater is hot-flushed through the normal drain pipe; otherwise, the high-pressure heater is hot-flushed through the endangered drain pipe;
[0054] When the pressure on the water inlet pipe of the first high-pressure heater is higher than the preset first threshold value, the fifth valve is closed, and the first high-pressure heater is hot-flushed through the hazardous drain pipe on the first high-pressure heater; otherwise, the fifth valve is opened, and the second valve on the hazardous drain pipe between the first high-pressure heater and the deaerator is closed;
[0055] When the pressure on the water inlet pipe of the second high-pressure heater is higher than the preset second threshold value, the sixth valve is closed and the second high-pressure heater and the first high-pressure heater are hot-flushed through the hazardous drain pipe on the second high-pressure heater; otherwise, the sixth valve is opened and the second valve on the hazardous drain pipe between the second high-pressure heater and the deaerator is closed.
[0056] Embodiment 3:
[0057] This embodiment provides a thermal power generation system, which adopts the high-pressure heater drain pipe flushing device as described in Example 1; other devices and configurations of the thermal power generation system can be implemented by conventional technologies and will not be described in detail here.
[0058] The above description is only a preferred embodiment of the present embodiment and is not intended to limit the present embodiment. For those skilled in the art, the present embodiment may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present embodiment shall be included in the protection scope of the present embodiment.
Claims
1. A high-pressure heater drain pipe flushing device, characterized in that: It includes a plurality of interconnected high pressure heaters, a hydrophobic expansion tank and a deaerator; The drain expansion tank is connected to the deaerator; one of the high-pressure heaters is connected to the deaerator through a normal drain pipeline; at least one high-pressure heater is connected to the drain expansion tank through a dangerous drain pipeline; The normal drain pipe is provided with a first valve and a third valve at one end close to the deaerator, and the third valve is located between the first valve and the deaerator; the endangered drain pipe is provided with a second valve; an auxiliary pipe is provided between the normal drain pipe and the drain expansion tank, the inlet of the auxiliary pipe is located between the first valve and the third valve, and the auxiliary pipe is provided with a fourth valve; At the initial start-up of the thermal power plant, when the preset conditions are met, the second valve and the third valve are closed, the first valve and the fourth valve are opened, and the high-pressure heater is hot-flushed through the normal drain pipe.
2. A high-pressure heater drain pipe flushing device as claimed in claim 1, characterized in that: The deaerator is connected to a first high-pressure heater, a second high-pressure heater and a third high-pressure heater which are interconnected through the normal drain pipe; a fifth valve is arranged on the normal drain pipe between the first high-pressure heater and the second high-pressure heater, a sixth valve is arranged on the normal drain pipe between the second high-pressure heater and the third high-pressure heater, and the third high-pressure heater is connected to the deaerator through the normal drain pipe.
3. A high-pressure heater drain pipe flushing device as claimed in claim 2, characterized in that: The first high-pressure heater, the second high-pressure heater and the third high-pressure heater are connected to the drain expansion tank through a dangerous drain pipeline and a second valve, respectively.
4. A high-pressure heater drain pipe flushing device as claimed in claim 1, characterized in that: A seventh valve is provided on the pipeline between the hydrophobic expansion tank and the deaerator.
5. A high-pressure heater drain pipe flushing device as claimed in claim 4, characterized in that: A pressure-release water pipe is connected to the pipeline between the seventh valve and the deaerator through the pipeline and the eighth valve.
6. A high-pressure heater drain pipe flushing device as claimed in claim 4, characterized in that: The pipeline between the seventh valve and the hydrophobic expansion tank is connected to the overflow port of the deaerator through the pipeline and the ninth valve.
7. A high-pressure heater drain pipe flushing device as claimed in claim 1, characterized in that: The deaerator is provided with a startup exhaust port and an operation exhaust port.
8. A method for flushing a high-pressure heater drain pipe, characterized in that: A high-pressure heater drain pipe flushing device as described in any one of claims 1 to 7 is used, comprising: at the initial start-up of the thermal power plant, when the preset conditions are met, closing the second valve and the third valve, opening the first valve and the fourth valve, and hot flushing the high-pressure heater through the normal drain pipe.
9. A method for flushing a high-pressure heater drain pipe according to claim 8, characterized in that: When the pressures on the water inlet pipes of the first high-pressure heater, the second high-pressure heater and the third high-pressure heater are respectively lower than the corresponding preset values, the second valve and the third valve are closed, the first valve and the fourth valve are opened, and the high-pressure heater is hot-flushed through the normal drain pipe; otherwise, the high-pressure heater is hot-flushed through the endangered drain pipe; When the pressure on the water inlet pipe of the first high-pressure heater is higher than the preset first threshold value, the fifth valve is closed, and the first high-pressure heater is hot-flushed through the hazardous drain pipe on the first high-pressure heater; otherwise, the fifth valve is opened, and the second valve on the hazardous drain pipe between the first high-pressure heater and the deaerator is closed; When the pressure on the water inlet pipe of the second high-pressure heater is higher than the preset second threshold value, the sixth valve is closed and the second high-pressure heater and the first high-pressure heater are hot-flushed through the hazardous drain pipe on the second high-pressure heater; otherwise, the sixth valve is opened and the second valve on the hazardous drain pipe between the second high-pressure heater and the deaerator is closed.
10. A thermal power generation system, characterized in that: A high-pressure heater drain pipe flushing device as described in any one of claims 1 to 7 is used.