Flushing system for high-back-pressure heat supply condensation water pipeline of air cooling unit and operation method

Abstract

The invention discloses an air cooling unit high-back-pressure heat supply condensation water pipeline flushing system and an operation method, the system comprises a hot well, an air cooling island exhaust device, a pipeline flushing pump and a high-level water tank, and the hot well and the air cooling island exhaust device are connected through a first condensation water pipeline and a second condensation water pipeline; a first valve group is arranged on the first condensed water pipeline, a second valve group is arranged on the second condensed water pipeline, and the first valve group and the second valve group are connected to a drainage trench through a first flushing pipeline; the pipeline flushing pump is arranged on the first flushing pipeline, an inlet and an outlet of the pipeline flushing pump are connected with the second flushing pipeline, and the high-level water tank is arranged on the second flushing pipeline; according to the system, the condensation water pipeline can be effectively flushed, the situation that water quality exceeds the standard and influences safe operation of the unit is avoided, meanwhile, the vacuum leakproofness of the system can be guaranteed in the flushing process, and normal operation of the unit cannot be influenced.

Description

Technical Field

[0001] The invention relates to the technical field of condensate pipe flushing, and in particular to a high back pressure heating condensate pipe flushing system for an air cooling unit and an operating method. Background Art

[0002] At this stage, the energy conservation and emission reduction of the unit and the benefits of the power plant are taken into consideration. In order to recover the cold source loss of the unit, power plants with heating areas have developed a variety of technical routes, among which the high back pressure circulating water heating technology route for air-cooled units is the most common. The exhaust steam cold source loss of the unit is recovered by adding a new exhaust steam heating condenser. Usually, the installed exhaust steam heating condenser and the original air-cooling island module are operated in parallel. The exhaust steam condensate of the air-cooling island module enters the exhaust device of the air-cooling island, and the condensate of the exhaust steam heating condenser enters the hot well. In order to make all the condensed water from the two routes converge into the condensate system, it is necessary to collect all the condensed water in the hot well into the exhaust device of the air-cooling island.

[0003] Due to the pressure loss of the condensate pipeline and valve from the hot well to the air-cooling island exhaust device, in order to prevent the condensate in the hot well from being unable to be discharged into the air-cooling island exhaust device, the overall elevation of the exhaust steam heating condenser is generally raised, and the condensate pressure is used to achieve gravity flow of the condensate from the hot well to the air-cooling island exhaust device.

[0004] The existing flushing system only considers the flushing of the air-cooled island module, and cannot realize the flushing of the condensate pipe from the hot well to the air-cooled island exhaust device. Since the air-cooled island exhaust device is in a vacuum negative pressure state, the condensate pipe from the hot well to the air-cooled island exhaust device only operates during the heating period. If the condensate pipe is not flushed, the water quality will exceed the standard, affecting the safe operation of the unit. In addition, in the prior art, a sewage pipe is generally directly connected to the condensate pipe. Since the entire system is in a vacuum negative pressure state, directly connecting a sewage pipe to the condensate pipe not only fails to achieve the sewage discharge effect, but also affects the vacuum system of the entire unit, causing vacuum leakage and affecting the safety of the unit. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a high back-pressure heating condensate water pipeline flushing system and operation method for an air-cooled unit, which can effectively flush the condensate water pipeline and avoid the impact of excessive water quality on the safe operation of the unit. At the same time, the vacuum airtightness of the system can be ensured during the flushing process without affecting the normal operation of the unit.

[0006] The technical solution of the present invention is as follows:

[0007] In a first aspect of the present invention, a high back pressure heating condensate water pipeline flushing system for an air-cooled unit is provided, comprising a hot well, an air-cooled island exhaust device, a pipeline flushing pump and a high-level water tank, wherein the hot well and the air-cooled island exhaust device are connected via a first condensate water pipeline and a second condensate water pipeline;

[0008] A first valve group is arranged on the first condensate water pipeline, and a second valve group is arranged on the second condensate water pipeline. The first valve group and the second valve group are connected to the drainage ditch through a first flushing pipeline; the pipeline flushing pump is arranged on the first flushing pipeline, and the inlet and outlet of the pipeline flushing pump are connected to the second flushing pipeline. The high-level water tank is arranged on the second flushing pipeline, and the high-level water tank and the pipeline flushing pump form a closed circulation loop through the second flushing pipeline.

[0009] In some embodiments of the present invention, a third valve group, a check valve, a pipeline flushing pump and a fourth valve group are sequentially arranged on the first flushing pipeline.

[0010] In some embodiments of the present invention, a fifth valve group, a high-level water tank and a sixth valve group are sequentially arranged on the second flushing pipeline.

[0011] In some embodiments of the present invention, the hot well is connected to a waste steam heating condenser, and the waste steam heating condenser is connected to the steam turbine exhaust through a first exhaust pipe, and a seventh valve group is provided on the first exhaust pipe.

[0012] In some embodiments of the present invention, the air-cooling island exhaust device is connected to the air-cooling island module, and the air-cooling island exhaust device is connected to the turbine exhaust through a second exhaust pipe, and an eighth valve group is provided on the second exhaust pipe.

[0013] In some embodiments of the present invention, a water quality detection device is further included, and the water quality detection device is arranged at the outlet of the first flushing pipeline.

[0014] In some embodiments of the present invention, a control device is further included, and the control device is electrically connected to the water quality detection device, the pipeline flushing pump and each valve group.

[0015] In some embodiments of the present invention, the air-cooling island exhaust device is also connected to the condensate system through a pipeline.

[0016] In a second aspect of the present invention, a method for operating a high back pressure heating condensate water pipeline flushing system of an air cooling unit is provided, comprising the following steps:

[0017] At the initial stage of operation of the exhaust steam heating condenser, close the second valve group, connect the first condensate pipe with the first flushing pipe and the second flushing pipe to form a condensate flushing recirculation system;

[0018] When the water level in the high-level water tank rises significantly, gradually connect the first flushing pipe with the drainage ditch. When water flows out of the outlet of the first flushing pipe, gradually disconnect the second flushing pipe until the first flushing pipe is completely connected with the drainage ditch and the second flushing pipe is completely disconnected.

[0019] When the water quality discharged from the first flushing pipe is qualified, gradually open the second valve group and gradually disconnect the connection between the first flushing pipe and the drainage ditch until the second valve group is fully opened, completely disconnecting the connection between the first flushing pipe and the drainage ditch, and completing the flushing of the entire condensate water pipe.

[0020] In some embodiments of the present invention, during normal heating, the seventh valve group and the eighth valve group are opened, and the exhaust steam enters the exhaust steam heating condenser and the air-cooling island module respectively for exhaust steam cooling, and the cooled exhaust steam enters the hot well and the air-cooling island exhaust device respectively.

[0021] One or more technical solutions of the present invention have the following beneficial effects:

[0022] (1) The high back pressure heating condensate water pipe flushing system for air-cooled units provided by the present invention can automatically flush the condensate water pipe until it is qualified when the unit is running by installing a condensate water pipe flushing system consisting of multiple valve groups, a pipe flushing pump, a high-level water tank and two flushing pipes.

[0023] (2) The high back-pressure heating condensate water pipe flushing system for air-cooled units provided by the present invention has an additional check valve which is a check vacuum valve group, which prevents vacuum leakage during the flushing process to avoid affecting the safety of the unit; the height of the additional high-level water tank is higher than the height of the flushing pump, so that there is a certain water pressure at the inlet of the flushing pump, which can enable the pump to start and run normally; the additional flushing pump recirculation system can achieve normal operation of the flushing pump before the system establishes a vacuum.

[0024] (3) The high back pressure heating condensate water pipe flushing system for the air-cooling unit provided by the present invention interlocks the water level device of the high-level water tank with the valve group. When the water level of the high-level water tank rises to a certain value, the fourth valve group of the interlock automatically opens slowly and the fifth valve group automatically closes slowly to prevent the high-level water tank from leaking due to full water.

[0025] (4) The operating method of the high back pressure heating condensate water pipeline flushing system of the air-cooled unit provided by the present invention is to first operate the second flushing pipeline, and operate the recirculation system formed by the flushing pump, the second flushing pipeline and the high-level water tank. Through the suction of the flushing pump, a negative pressure is formed in front of the flushing pump, and the check valve group is opened to allow the condensate water in the hot well to pass through the first condensate water pipeline and the first flushing pipeline and be pumped into the high-level water tank. When the water level in the high-level water tank rises, it means that the check valve has been opened. At this time, the fourth valve group can be gradually opened to discharge the condensate water into the ditch to achieve the flushing of the condensate water pipeline. The entire flushing process will not cause system vacuum leakage and will not affect the safe operation of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the high back pressure heating condensate water pipeline flushing system for an air cooling unit of the present invention.

[0027] In the figure: 1. hot well; 2. first valve group; 3. first condensate pipeline; 4. second condensate pipeline; 5. second valve group; 6. first flushing pipeline; 7. third valve group; 8. check valve; 9. pipeline flushing pump; 10. fourth valve group; 11. second flushing pipeline; 12. fifth valve group; 13. high-level water tank; 14. sixth valve group; 15. exhaust steam heating condenser; 16. air-cooled island exhaust device; 17. first exhaust pipeline; 18. seventh valve group; 19. second exhaust pipeline; 20. eighth valve group; 21. steam turbine; 22. air-cooled island module. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0029] Example 1

[0030] In a typical embodiment of the present invention, a high back pressure heating condensate water pipeline flushing system for an air cooling unit is provided. Figure 1 As shown, it includes a hot well 1, an air-cooled island exhaust device 16, a pipeline flushing pump 9 and a high-level water tank 13, and the hot well 1 and the air-cooled island exhaust device 16 are connected through a first condensate pipeline 3 and a second condensate pipeline 4;

[0031] A first valve group 2 is arranged on the first condensate water pipe 3, and a second valve group 5 is arranged on the second condensate water pipe 4. The first valve group 2 and the second valve group 5 are connected to the drainage ditch through a first flushing pipe 6; the pipe flushing pump 9 is arranged on the first flushing pipe 6, and the inlet and outlet of the pipe flushing pump 9 are connected to the second flushing pipe 11. The high-level water tank 13 is arranged on the second flushing pipe 11, and the high-level water tank 13 and the pipe flushing pump 9 form a closed circulation loop through the second flushing pipe 11.

[0032] Furthermore, the first flushing pipeline 6 is provided with a third valve group 7 , a check valve 8 , a pipeline flushing pump 9 and a fourth valve group 10 in sequence.

[0033] Furthermore, a fifth valve group 12 , a high-level water tank 13 and a sixth valve group 14 are sequentially arranged on the second flushing pipeline 11 .

[0034] By connecting the first flushing pipe 6 and the second flushing pipe 11 to the first condensate pipe 3 and the second condensate pipe 4, the condensate pipes are fully flushed using the condensate in the hot well 1 and the air-cooling island exhaust device 16.

[0035] In this embodiment, the hot well 1 is connected to the exhaust steam heating condenser 15 , and the exhaust steam heating condenser 15 is connected to the steam turbine 21 exhaust through the first exhaust steam pipe 17 , and the first exhaust steam pipe 17 is provided with a seventh valve group 18 .

[0036] Furthermore, the air-cooling island exhaust device 16 is connected to the air-cooling island module 22 , and the air-cooling island exhaust device 16 is connected to the steam turbine 21 exhaust through a second exhaust pipe 19 , and an eighth valve group 20 is provided on the second exhaust pipe 19 .

[0037] During normal heating, the seventh valve group 18 and the eighth valve group 20 are opened, and the exhaust steam enters the exhaust steam heating condenser 15 and the air-cooling island module 22 for exhaust steam cooling. The cooled exhaust steam enters the hot well 1 and the air-cooling island exhaust device 16 respectively.

[0038] Furthermore, it also includes a water quality detection device, which is arranged at the outlet of the first flushing pipeline 6, and the water quality of the water discharged from the first flushing pipeline 6 is detected in real time by the arranged water quality detection device. It also includes a control device, which is electrically connected with the water quality detection device, the pipeline flushing pump and each valve group, and the opening and closing of each valve group are controlled by the control device to realize the operation of the system.

[0039] Furthermore, the air-cooling island exhaust device is also connected to the condensate water system through a pipeline, so that all the condensate water from the two routes is collected and enters the condensate water system.

[0040] The method for using the high back pressure heating condensate water pipeline flushing system for air cooling units provided in this embodiment is as follows:

[0041] During normal heating period, the seventh valve group 18 and the eighth valve group 20 are opened, and the exhaust steam enters the exhaust steam heating condenser 15 and the air cooling island module 22 for exhaust steam cooling. The cooled exhaust steam enters the hot well 1 and the air cooling island exhaust device 16 respectively. In the early stage of operation of the exhaust steam heating condenser 15, due to poor water quality, the second valve group 5 is closed, the first valve group 2 is opened, the third valve group 7 is opened, the pipeline flushing pump 9 is opened, the fourth valve group 10 is closed, the fifth valve group 12 is opened, and the sixth valve group 14 is opened. The first valve group 2, the high-level water tank 13, the third valve group 7, the pipeline flushing pump 9 and the connected pipelines form a condensate flushing recirculation system.

[0042] When the water level in the high-level water tank rises significantly, gradually open the fourth valve group 10. After seeing water flowing out, gradually close the fifth valve group 12 and the sixth valve group 14 until the fourth valve group 10 is fully opened and the fifth valve group 12 and the sixth valve group 14 are fully closed.

[0043] When the discharged water quality is qualified after the fourth valve group 10 is tested, the second valve group 5 is gradually opened, and the fourth valve group 10 is gradually closed until the second valve group 5 is fully opened and the fourth valve group 10 is fully closed, completing the flushing of the entire condensate system.

[0044] The working principle is: normal condensate flows from the hot well 1 through the first condensate pipe 3 directly into the air-cooled island exhaust device 16, and then enters the boiler to generate steam to complete the cycle. Since this pipeline is only operated in winter, there will be rust and dirt inside the pipeline. The boiler has high requirements for water quality. If it is not cleaned to meet the water quality requirements, it will cause harm to the boiler under high temperature and high pressure, so it must be cleaned. For normal pipeline system cleaning, you can directly open the opening to clean the drain ditch, but since the pipelines between the hot well 1 and the air-cooled island exhaust device 16 are all vacuum connected, a flushing pump is needed to create another vacuum to pump the condensate system to achieve the purpose of flushing. The purpose of the high-level water tank is to be higher than the inlet of the flushing pump, so that the inlet water pressure of the flushing pump is formed, so that the flushing pump can start and run automatically. After the flushing pump is running, a vacuum will slowly form between the check valve 8 and the pipeline flushing pump 9 through the closed circulation system established by the high-level water tank and the flushing pump, until the check valve 8 is opened to pump out the condensate in the first condensate pipe 3. In this way, there will be more water in the closed system of the high-level water tank and the pump, and the water level in the high-level water tank will rise. By the rising water level, it can be judged that the check valve 8 has been opened, and the condensate in the hot well is gradually pumped out. At this time, the purpose of the recycling system is achieved. In order to stabilize the operation of the position, the recycling system is slowly closed, and the flushing system is slowly opened at the same time.

[0045] The high back-pressure heating condensate pipe flushing system for the air-cooled unit provided in this embodiment can automatically flush the condensate pipe until it is qualified when the unit is running by adding a plurality of valve groups, a pipe flushing pump, a high-level water tank and a condensate pipe flushing system composed of two flushing pipes.

[0046] Example 2

[0047] In a typical embodiment of the present invention, a method for operating a high back pressure heating condensate water pipeline flushing system of an air cooling unit is provided, comprising the following steps:

[0048] At the initial stage of operation of the exhaust steam heating condenser, close the second valve group, connect the first condensate pipe with the first flushing pipe and the second flushing pipe to form a condensate flushing recirculation system;

[0049] When the water level in the high-level water tank rises significantly, gradually connect the first flushing pipe with the drainage ditch. When water flows out of the outlet of the first flushing pipe, gradually disconnect the second flushing pipe until the first flushing pipe is completely connected with the drainage ditch and the second flushing pipe is completely disconnected.

[0050] When the water quality discharged from the first flushing pipe is qualified, gradually open the second valve group and gradually disconnect the connection between the first flushing pipe and the drainage ditch until the second valve group is fully opened, completely disconnecting the connection between the first flushing pipe and the drainage ditch, and completing the flushing of the entire condensate water pipe.

[0051] In addition, during normal heating, the seventh valve group and the eighth valve group are opened, and the exhaust steam enters the exhaust steam heating condenser and the air-cooling island module respectively for exhaust steam cooling. The cooled exhaust steam enters the hot well and the air-cooling island exhaust device respectively.

[0052] The operating method of the high back pressure heating condensate pipe flushing system of the air-cooling unit provided in this embodiment is to first operate the second flushing pipe, and operate the recirculation system formed by the flushing pump, the second flushing pipe and the high-level water tank. The flushing pump is used to suck to form a negative pressure in front of the flushing pump, and the check valve group is opened to allow the condensate in the hot well to pass through the first condensate pipe and the second condensate pipe and be pumped into the high-level water tank. When the water level in the high-level water tank rises, it means that the check valve has been opened. At this time, the fourth valve group can be gradually opened to discharge the condensate into the ditch to achieve the flushing of the condensate pipe. The entire flushing process will not cause system vacuum leakage and will not affect the safe operation of the unit.

[0053] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A high back pressure heating condensate water pipeline flushing system for air cooling units, characterized in that: It includes a hot well, an air-cooling island exhaust device, a pipeline flushing pump and a high-level water tank, wherein the hot well and the air-cooling island exhaust device are connected via a first condensate pipeline and a second condensate pipeline; A first valve group is arranged on the first condensate water pipeline, and a second valve group is arranged on the second condensate water pipeline. The first valve group and the second valve group are connected to the drainage ditch through a first flushing pipeline; the pipeline flushing pump is arranged on the first flushing pipeline, and the inlet and outlet of the pipeline flushing pump are connected to the second flushing pipeline. The high-level water tank is arranged on the second flushing pipeline, and the high-level water tank and the pipeline flushing pump form a closed circulation loop through the second flushing pipeline.

2. The high back pressure heating condensate water pipeline flushing system for air cooling unit according to claim 1, characterized in that: The first flushing pipeline is sequentially provided with a third valve group, a check valve, a pipeline flushing pump and a fourth valve group.

3. The high back pressure heating condensate water pipeline flushing system for air cooling unit according to claim 1, characterized in that: The second flushing pipeline is sequentially provided with a fifth valve group, a high-level water tank and a sixth valve group.

4. The high back pressure heating condensate water pipeline flushing system for air cooling unit according to claim 1, characterized in that: The hot well is connected to the exhaust steam heating condenser, and the exhaust steam heating condenser is connected to the turbine exhaust through the first exhaust steam pipeline, and the first exhaust steam pipeline is provided with a seventh valve group.

5. The high back pressure heating condensate water pipeline flushing system for air cooling unit according to claim 1, characterized in that: The air-cooling island exhaust device is connected to the air-cooling island module, and the air-cooling island exhaust device is connected to the steam turbine exhaust through a second exhaust pipe, and an eighth valve group is arranged on the second exhaust pipe.

6. The high back pressure heating condensate water pipeline flushing system for air cooling unit according to claim 1, characterized in that: It also includes a water quality detection device, which is arranged at the outlet of the first flushing pipeline.

7. The high back pressure heating condensate water pipeline flushing system for air cooling unit according to claim 6, characterized in that: It also includes a control device, which is electrically connected to the water quality detection device, the pipeline flushing pump and each valve group.

8. The high back pressure heating condensate water pipeline flushing system for air cooling unit according to claim 1, characterized in that: The air-cooling island exhaust device is also connected to the condensate water system through a pipeline.

9. An operating method for a high back pressure heating condensate water pipeline flushing system for an air cooling unit according to any one of claims 1 to 8, characterized in that: The following steps are involved: At the initial stage of operation of the exhaust steam heating condenser, close the second valve group, connect the first condensate pipe with the first flushing pipe and the second flushing pipe to form a condensate flushing recirculation system; When the water level in the high-level water tank rises significantly, gradually connect the first flushing pipe with the drainage ditch. When water flows out of the outlet of the first flushing pipe, gradually disconnect the second flushing pipe until the first flushing pipe is completely connected with the drainage ditch and the second flushing pipe is completely disconnected. When the water quality discharged from the first flushing pipe is qualified, gradually open the second valve group and gradually disconnect the connection between the first flushing pipe and the drainage ditch until the second valve group is fully opened, completely disconnecting the connection between the first flushing pipe and the drainage ditch, and completing the flushing of the entire condensate water pipe.

10. The operating method of the high back pressure heating condensate water pipeline flushing system of the air cooling unit according to claim 9, characterized in that: During normal heating, the seventh valve group and the eighth valve group are opened, and the exhaust steam enters the exhaust steam heating condenser and the air-cooling island module respectively for exhaust steam cooling. The cooled exhaust steam enters the hot well and the air-cooling island exhaust device respectively.

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