Method and system for removing condensate water of directly-buried heat supply pipeline

Abstract

The invention discloses a method and system for removing condensate water of a direct burial heat supply pipeline, and relates to the technical field of heat supply pipe network maintaining.The method comprises the steps that a direct burial heat supply pipeline valve is arranged, a miscellaneous gas system is connected, and compressed air purging is conducted, and the system comprises an air compressor module, a compressed air storage tank module, a connecting module and a steam heat supply pipe network module; when in use, the existing equipment, namely a miscellaneous gas system of a power plant, is connected into the heat supply pipeline to replace a temporary diesel air compressor to blow out condensate water in the directly-buried heat supply pipeline, so that the pipe heating time of a heat supply pipe network is shortened, the pipe heating working efficiency is improved, the water attack phenomenon during pipe heating of the directly-buried heat supply pipeline is effectively prevented, and the safety of the heat supply pipe network is guaranteed; when not in use, the state of each valve of the steam heat supply pipe network module is recovered at the same time, so that the heat supply pipeline is reliably isolated from a power plant miscellaneous gas system during heating and commissioning, and the respective systems are independent.

Description

Technical Field

[0001] The present invention relates to the technical field of heat supply pipeline maintenance, and in particular to a method and system for removing condensate from directly buried heat supply pipelines. Background Art

[0002] In the heat supply steam pipeline system of a power plant, since the directly buried heat supply pipeline is buried underground, its steam trap is installed on the ground. When the pipeline stops operating from the hot state to the cold state, the condensate generated in the pipeline cannot be effectively discharged through the conventional steam trap due to the disappearance of the steam pressure under the cold state working condition, resulting in a large amount of condensate accumulating in the heat supply pipeline. When the pipeline network is heated again, the contact between the high-temperature steam and the low-temperature accumulated water will cause a violent water hammer phenomenon, resulting in violent vibration of the pipeline, damage to the supports, and even pipeline rupture, seriously threatening the safety of the heat supply system.

[0003] In reality, generally, extending the pipeline heating time or temporarily blowing with an air compressor is adopted to solve the problem. Extending the pipeline heating time is to gradually vaporize the accumulated water by slowly heating up, but this method takes too much time, resulting in a large waste of steam working medium and affecting the heat supply efficiency; while temporarily blowing with an air compressor is to externally connect a diesel air compressor to compress air to blow the pipeline before heating the pipeline, but there are problems such as inconvenient movement of the equipment, high operating cost, and unstable blowing pressure, making it difficult to be popularized and applied in the conventional operation and maintenance of power plants.

[0004] Therefore, there is an urgent need to develop a technical solution that is compatible with the existing system of the power plant and can efficiently remove the cold-state accumulated water in the directly buried pipeline, and under the condition of not requiring too high cost, remove the condensate in the heat supply pipeline and avoid the violent water hammer phenomenon caused by the contact between high-temperature steam and low-temperature accumulated water. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is: to remove the condensate in the heat supply pipeline at a relatively low cost.

[0006] The above technical problem is solved by the following technical solutions:

[0007] The present invention provides a method for removing condensate from directly buried heat supply pipelines, which includes configuring valves for directly buried heat supply pipelines, connecting the miscellaneous gas system, and purging with compressed air.

[0008] In a preferred embodiment of the method for removing condensate from directly buried heat supply pipelines of the present invention: configure valves for directly buried heat supply pipelines, set a path for introducing compressed air into the directly buried heat supply pipeline and discharging condensate unidirectionally; connect the miscellaneous gas system to conveniently provide compressed air for the directly buried heat supply pipeline and provide the power for discharging condensate; purge with compressed air, and use the compressed air of the miscellaneous gas system to purge the directly buried heat supply pipeline to discharge condensate.

[0009] In a preferred embodiment of the method for removing condensate from directly buried heating pipelines according to the present invention: The configuration of the directly buried heating pipeline valves includes opening the front isolation valve and the drain bypass valve of the directly buried heating pipeline, and simultaneously closing the drain trap isolation valve and the rear isolation valve of the directly buried heating pipeline.

[0010] In a preferred embodiment of the method for removing condensate from directly buried heating pipelines according to the present invention: The connection to the miscellaneous gas system includes connecting the miscellaneous gas system of the power plant to the isolation valve on the heating pipeline side through a flange-connected short pipe.

[0011] In a preferred embodiment of the method for removing condensate from directly buried heating pipelines according to the present invention: The compressed air purging includes slowly opening the isolation valve on the miscellaneous gas side and the isolation valve on the heating pipeline side, using the compressed air provided by the miscellaneous gas system to purge the condensate in the directly buried heating pipeline, and monitoring the control valve opening at the discharge port of the drain bypass valve to maintain the purging pressure until no more water accumulates is discharged.

[0012] In a preferred embodiment of the method for removing condensate from directly buried heating pipelines according to the present invention: The drain bypass valve is the condensate discharge port. Closing the drain trap isolation valve blocks the drainage function of the conventional drain trap. Closing the rear isolation valve isolates the rear end of the pipeline, ensuring that the compressed air only flows unidirectionally through the drain bypass valve during the purging process.

[0013] In a preferred embodiment of the method for removing condensate from directly buried heating pipelines according to the present invention: The diameter of the flange-connected short pipe is DN80 - DN150, and the compressed air flow rate during purging is 700 - 850 m 3 / h; The miscellaneous gas system controls the gas flow direction and system isolation through a check valve and an isolation valve.

[0014] In a preferred embodiment of the method for removing condensate from directly buried heating pipelines according to the present invention: After purging, close the isolation valve on the miscellaneous gas side and the isolation valve on the heating pipeline side, remove the flange-connected short pipe, and restore the initial state of the drain trap isolation valve and the rear isolation valve to ensure the independent operation of the heating pipeline and the miscellaneous gas system.

[0015] The present invention also proposes a system for removing condensate from directly buried heating pipelines, which includes an air compressor module, a compressed air storage tank module, a connection module, and a steam heating pipe network module.

[0016] In a preferred embodiment of the system for removing condensate from directly buried heating pipelines according to the present invention: The air compressor module includes an air compressor, a check valve at the air compressor outlet, and an isolation valve at the air compressor outlet. The air compressor is connected through the check valve at the air compressor outlet and the isolation valve at the air compressor outlet. There is at least one group of the air compressor modules; The compressed air storage tank module is connected to the air compressor module and includes an isolation valve at the compressed air storage tank inlet, a compressed air storage tank, and an isolation valve at the compressed air storage tank outlet. The isolation valve at the compressed air storage tank inlet is connected to the isolation valve at the air compressor outlet; The connection module is connected to the compressed air storage tank module and includes an isolation valve on the miscellaneous gas side, a detachable flange connection short pipe, and an isolation valve on the heating pipeline side. The detachable flange connection short pipe connects the isolation valve on the miscellaneous gas side and the isolation valve on the heating pipeline side. The isolation valve on the miscellaneous gas side is connected to the compressed air storage tank module; The steam heating pipe network module is connected to the connection module and includes an isolation valve before the directly buried heating pipeline, a directly buried heating pipeline, a steam trap for the directly buried heating pipeline, a bypass valve for the steam trap of the directly buried heating pipeline, and an isolation valve for the steam trap of the directly buried heating pipeline. The directly buried heating pipeline is connected to the isolation valve on the heating pipeline side. The steam trap for the directly buried heating pipeline is arranged between the two isolation valves for the steam trap of the directly buried heating pipeline. The bypass valve for the steam trap of the directly buried heating pipeline and the isolation valve for the steam trap of the directly buried heating pipeline are jointly connected to the directly buried heating pipeline. The isolation valve before the directly buried heating pipeline is arranged on the directly buried heating pipeline.

[0017] In a preferred embodiment of the system for removing condensate from directly buried heating pipelines according to the present invention: The air compressor module further includes a filter screen at the air compressor inlet, which is arranged at one end of the air compressor away from the check valve at the air compressor outlet; The compressed air storage tank module further includes a pressure gauge for the miscellaneous gas main pipe, which is arranged between the isolation valve at the compressed air storage tank outlet and the connection module; The steam heating pipe network module further includes a pressure gauge for the steam heating pipeline, which is arranged on the directly buried heating pipeline on the side of the isolation valve before the directly buried heating pipeline away from the connection module; The steam heating pipe network module further includes an isolation valve after the directly buried heating pipeline, which is arranged at one end of the directly buried heating pipeline away from the isolation valve before the directly buried heating pipeline on the side of the pressure gauge for the steam heating pipeline.

[0018] In a preferred embodiment of the system for removing condensate from directly buried heating pipelines according to the present invention: The steam heating pipe network module further includes a medium-pressure heating steam source, a low-pressure heating steam source, and a medium-pressure heating main pipe and a low-pressure heating main pipe arranged in parallel. The medium-pressure heating main pipe is connected to the medium-pressure heating steam source, and the low-pressure heating main pipe is connected to the low-pressure heating steam source.

[0019] The beneficial effects of the present invention are as follows: during use, by utilizing the existing equipment, i.e., the miscellaneous gas system of the power plant, it is connected to the heating pipeline to replace the temporary diesel air compressor, blowing out the condensate in the directly buried heating pipeline, reducing the warm-up time of the heating pipe network, improving the warm-up work efficiency, effectively preventing the water hammer phenomenon during the warm-up of the directly buried heating pipeline, and ensuring the safety of the heating pipe network; when not in use, the states of the valves of each module of the steam heating pipe network are restored at the same time to ensure reliable isolation from the miscellaneous gas system of the power plant and the independence of each system during the warm-up and operation of the heating pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below only relate to some embodiments of the present invention and do not limit the present invention.

[0021] Figure 1 Shows a flowchart of a method for removing condensate from a directly buried heating pipeline;

[0022] Figure 2 Shows a schematic diagram of a system for removing condensate from a directly buried heating pipeline. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] In order to enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below in conjunction with the specific embodiments and the drawings.

[0024] The terms used in the present invention are those general terms that are currently widely used in the art in consideration of the functions of the present invention, but these terms may change according to the intentions of those of ordinary skill in the art, precedents, or new technologies in the art. In addition, specific terms may be selected by the applicant, and in this case, their detailed meanings will be described in the detailed description of the present invention. Therefore, the terms used in the specification should not be understood as simple names, but based on the meanings of the terms and the overall description of the present invention.

[0025] Referring to Figure 1 , this embodiment provides a method for removing condensate from a directly buried heating pipeline, including configuring the valves of the directly buried heating pipeline, connecting the miscellaneous gas system, and purging with compressed air.

[0026] Among them, a directly buried heating pipeline valve is configured to set a path for introducing compressed air into the directly buried heating pipeline and discharging condensed water unidirectionally. The directly buried heating pipeline of the power plant is laid underground, and its steam trap is installed on the ground. Under cold conditions, the drainage of the pipeline cannot be discharged through the differential pressure between steam and the atmosphere like in the hot state. Therefore, a large amount of condensed water in the directly buried heating pipeline will accumulate in the heating pipeline under cold conditions. When the heating steam pipe network is put into operation again for pipe warming, the steam needs to carry away a large amount of condensed water and pipe warming drainage, which greatly affects the time for pipe warming of the heating pipe network. Otherwise, it will cause serious water hammer phenomenon in the heating pipeline. Therefore, it is necessary to discharge the condensed water in the directly buried heating pipeline before network warming.

[0027] Connect to the miscellaneous gas system to facilitate providing compressed air for the directly buried heating pipeline and providing the power to discharge condensed water. Generally, a diesel air compressor is used to blow out the condensed water from the directly buried heating pipeline. However, the diesel air compressor has problems such as inconvenient equipment movement, high operating cost of consuming diesel, and unstable purging pressure. The power plant has its own miscellaneous gas system, which can directly use the existing equipment.

[0028] Compressed air purging is used to purge the directly buried heating pipeline with the compressed air of the miscellaneous gas system to discharge the condensed water. For example, the third-phase air compressor room is equipped with 4 screw air compressors with a rated flow rate of 41 m 3 / min and a rated head of 0.8 MPa, among which 3 are for instrument use and 1 is for miscellaneous use. According to Bernoulli's equation, the flow rate is calculated based on the air flow differential pressure. The pressure of the third-phase miscellaneous gas main pipe is maintained at about 0.7 MPa. It is tentatively assumed that the air required to purge the accumulated water in the heating pipeline is 0.1 MPa, so the differential pressure is 0.6 MPa = 6 bar. If the diameter of the connecting short pipe is DN100, the average flow velocity is about 791 m 3 / h. Taking the low-pressure heating main pipe with a specification of Φ820×10 as an example, it takes about 6.5 hours to purge every 10 kilometers of the heating pipeline.

[0029] Specifically, configuring the directly buried heating pipeline valve includes opening the front isolation valve and the drain bypass valve of the directly buried heating pipeline, and closing the steam trap isolation valve and the rear isolation valve of the directly buried heating pipeline at the same time.

[0030] Opening the front isolation valve of the directly buried heating pipeline establishes an inlet channel for compressed air from the miscellaneous gas system to the directly buried pipeline, ensuring that the purging air flow covers the entire pipe section to be processed. Opening the drain bypass valve serves as an open condensed water discharge port, replacing the drainage function of the conventional steam trap, forming a unidirectional flow path, that is, compressed air → pipeline → bypass valve discharge; closing the steam trap isolation valve blocks the automatic drainage circuit of the steam trap to avoid the short-circuit loss of the purging air flow through the steam trap; closing the rear isolation valve isolates the unprocessed area at the rear end of the pipeline, so that the purging air flow acts concentratedly on the target water accumulation area.

[0031] Specifically, the connecting miscellaneous gas system includes connecting the miscellaneous gas system of the power plant to the isolation valve on the heat supply pipeline side through a flange-connected short pipe.

[0032] The size of the flange-connected short pipe is matched with the isolation valve on the heat supply pipeline side. After purging, the short pipe can be removed to avoid the risk of pressure inter-cascading caused by the long-term connection between the miscellaneous gas system and the heat supply pipeline. When not in use, the states of the valves of each module of the steam heat supply pipe network are restored at the same time to ensure reliable isolation from the miscellaneous gas system of the power plant and the independence of each system during the warm-up and commissioning of the heat supply pipeline.

[0033] Specifically, the compressed air purging includes slowly opening the isolation valve on the miscellaneous gas side and the isolation valve on the heat supply pipeline side, using the compressed air provided by the miscellaneous gas system to purge the condensed water in the directly buried heat supply pipeline, and monitoring the control valve opening of the drain bypass valve discharge port to maintain the purging pressure until no accumulated water is discharged.

[0034] When opening the valve on the miscellaneous gas side, the opening degree is linearly increased to avoid pressure impact in the pipeline, and the pressure difference is monitored in real time through the pressure gauge of the miscellaneous gas main pipe and the pipeline pressure gauge. When no liquid is discharged from the drain bypass valve, it indicates that the purging is completed.

[0035] Specifically, the drain bypass valve is the condensed water discharge port. Closing the trap isolation valve is used to block the drainage function of the conventional trap, and closing the rear isolation valve is used to isolate the rear end of the pipeline to ensure that the compressed air only flows unidirectionally through the drain bypass valve during the purging process.

[0036] The drain bypass valve serves as an open outlet to force the air flow to flow along the preset path, and during use, the discharge of condensed water in the branch can be judged by observation. The branch that is emptied first can be closed first to avoid local water accumulation residues caused by multi-path diversion.

[0037] Specifically, the diameter of the flange-connected short pipe is DN80 - DN₁₅₀, and the flow rate of the compressed air during purging is 700 - 850m 3 / h; the miscellaneous gas system controls the air flow direction and system isolation through a check valve and an isolation valve.

[0038] The flange-connected short pipe covers the requirements of heat supply pipelines with different diameters. For example, DN80 is used for Φ426 pipelines and DN150 is used for Φ1020 pipelines. When the pressure of the miscellaneous gas main pipe drops abnormally, the check valve at the air compressor outlet automatically cuts off to avoid backflow of pipeline condensed water and pollution of the gas source; the miscellaneous gas system constructs multiple isolations through the air compressor outlet valve, the storage tank outlet valve, the miscellaneous gas side valve, and the pipeline side valve to reduce the system isolation leakage rate.

[0039] Specifically, after purging is completed, close the isolation valves on the miscellaneous gas side and the isolation valves on the heat supply pipeline side, remove the flange connecting short pipe, and restore the initial states of the steam trap isolation valve and the rear isolation valve to ensure the independent operation of the heat supply pipeline and the miscellaneous gas system; when not in use, simultaneously restore the states of the valves of the steam heating pipe network module to ensure reliable isolation between the heat supply pipeline and the power plant miscellaneous gas system and the independent operation of each system during the warm-up and commissioning of the heat supply pipeline.

[0040] Refer to Figure 2 , this embodiment provides a system for removing condensate from a directly buried heat supply pipeline, including an air compressor module 1, a compressed air storage tank module 2, a connection module 4, and a steam heating pipe network module 3.

[0041] Specifically, the air compressor module 1 includes an air compressor 12, an air compressor outlet check valve 13, and an air compressor outlet isolation valve 14. The air compressor 12 is connected through the air compressor outlet check valve 13 and the air compressor outlet isolation valve 14, and there is at least one group of the air compressor module 1.

[0042] The air compressor module 1 serves as the core of the gas source power, ensuring redundant gas supply capacity through at least one group of air compressors 12, and the check valve prevents reverse air flow from contaminating the air compressor after purging.

[0043] The compressed air storage tank module 2 is connected to the air compressor module 1 and includes a compressed air storage tank inlet isolation valve 21, a compressed air storage tank 22, and a compressed air storage tank outlet isolation valve 23. The compressed air storage tank inlet isolation valve 21 is connected to the air compressor outlet isolation valve 14.

[0044] The storage tank module 2 serves as a pneumatic buffer unit, stabilizing the pressure of the miscellaneous gas main pipe to 0.7 MPa through the compressed air storage tank 22, and the compressed air storage tank inlet isolation valve 21 and the compressed air storage tank outlet isolation valve 23 achieve decoupling control of the compressed air storage tank 22 from the air compressor 12 and the downstream system.

[0045] The connection module 4 is connected to the compressed air storage tank module 2 and includes a miscellaneous gas side isolation valve 41, a detachable flange connecting short pipe 42, and a heat supply pipeline side isolation valve 43. The detachable flange connecting short pipe 42 connects the miscellaneous gas side isolation valve 41 and the heat supply pipeline side isolation valve 43, and the miscellaneous gas side isolation valve 41 is connected to the compressed air storage tank module 2.

[0046] The connection module 4 serves as a temporary channel, constructing a detachable gas path interface through the flange connecting short pipe 42 and the two side isolation valves, establishing a physical connection between the miscellaneous gas system and the heat supply pipeline during purging, and removing the short pipe after the operation to restore the system independence.

[0047] The steam heating pipe network module 3 is connected to the connection module 4 and includes a pre-buried heating pipe isolation valve 31, a pre-buried heating pipe 37, a pre-buried heating pipe steam trap 32, a bypass valve 33 for the pre-buried heating pipe steam trap, and an isolation valve 34 for the pre-buried heating pipe steam trap. The pre-buried heating pipe 37 is connected to the heating pipe side isolation valve 43. The pre-buried heating pipe steam trap 32 is arranged between two isolation valves 34 for the pre-buried heating pipe steam trap. The bypass valve 33 for the pre-buried heating pipe steam trap and the isolation valve 34 for the pre-buried heating pipe steam trap are jointly connected to the pre-buried heating pipe 37. The pre-buried heating pipe isolation valve 31 is arranged on the pre-buried heating pipe 37. The steam heating pipe network module 3 further includes a post-buried heating pipe isolation valve 35, which is arranged at one end of the steam heating pipe pressure gauge 36 on the pre-buried heating pipe 37 away from the pre-buried heating pipe isolation valve 31. A part of the pre-buried heating pipe 37 is laid underground under the ground 8.

[0048] During the normal operation of the heating system, the pre-buried heating pipe steam trap 32 automatically discharges the condensate in the pipe by using the steam pressure difference, and is installed at the low point of the pre-buried heating pipe 37, surrounded by the isolation valves 34 for the steam trap on both sides. It cannot work due to the lack of steam pressure difference in the cold state, and the bypass valve 33 needs to be used to replace the drainage.

[0049] Taking the steam heating pipe network module 3 as the operation object, the purging inlet is controlled by the pre-buried heating pipe isolation valve 31, and the drainage outlet is the bypass valve 33 for the pre-buried heating pipe steam trap. The isolation valve 34 for the pre-buried heating pipe steam trap and the post-buried heating pipe isolation valve 35 cooperate to block the interference in the non-target area.

[0050] Specifically, the air compressor module 1 further includes an air compressor inlet filter 11, which is arranged at one end of the air compressor 12 away from the air compressor outlet check valve 13. It filters the particulate matter in the intake air to prevent impurities from entering the air compressor module 1.

[0051] The compressed air storage tank module 2 further includes a miscellaneous air main pipe pressure gauge 24, which is arranged between the compressed air storage tank outlet isolation valve 23 and the connection module 4. It monitors the purging air source pressure in real time, dynamically calibrates the flow rate in combination with the Bernoulli equation, and triggers an alarm when the pressure fluctuation exceeds a large value.

[0052] The steam heating pipe network module 3 further includes a steam heating pipe pressure gauge 36, which is arranged on the pre-buried heating pipe 37 on the side of the pre-buried heating pipe isolation valve 31 away from the connection module 4. It directly reflects the purging pressure in the pre-buried pipe.

[0053] Specifically, the steam heating pipe network module 3 further includes a medium-pressure heating steam source 38, a low-pressure heating steam source 310, and a medium-pressure heating main pipe 39 and a low-pressure heating main pipe 311 arranged in parallel. The medium-pressure heating main pipe 39 is connected to the medium-pressure heating steam source 38, and the low-pressure heating main pipe 311 is connected to the low-pressure heating steam source 310.

[0054] The medium-pressure heating main pipe 39 is connected to the medium-pressure heating steam source 38 and is used for industrial steam users; the low-pressure heating main pipe 311 is connected to the low-pressure heating steam source 310 and is used for civil heating; the two main pipes are physically isolated through the isolation valve group and can be independently purged.

[0055] The medium-pressure heating steam source 38 and the low-pressure heating steam source 310 respectively provide steam sources for the medium-pressure main pipe 39 and the low-pressure main pipe 311. Before purging, the steam source valves need to be closed to prevent steam from interfering with the purging air flow in the reverse direction.

[0056] Specifically, the compressed air storage tank module 2 is also connected to each miscellaneous gas user 5 in the power plant. The miscellaneous gas users in the power plant refer to fixed equipment or facilities that rely on the miscellaneous gas system in the power plant for gas supply. It includes pneumatic valves, instrument air sources, and cleaning and purging equipment, etc. During the purging operation, the system pressure needs to be monitored through the miscellaneous gas main pipe pressure gauge 24 to ensure that the supply pressure ≥ 0.65 MPa. If the pressure is lower than this value, the standby air compressor will be triggered to start to avoid affecting the normal operation of the miscellaneous gas users.

[0057] The medium-pressure heating user 6 is arranged behind the post-isolation valve 35 of the directly buried heating pipeline on the medium-pressure heating main pipe 39. The low-pressure heating user 7 is arranged behind the post-isolation valve 35 of the directly buried heating pipeline on the low-pressure heating main pipe 311.

[0058] When the invention of our side is in use, it utilizes the existing equipment, that is, the miscellaneous gas system in the power plant, to access the directly buried heating pipeline 37, replaces the temporary diesel air compressor, blows out the condensed water in the directly buried heating pipeline 37, reduces the warm-up time of the directly buried heating pipeline 37, improves the warm-up work efficiency, effectively prevents the water hammer phenomenon during the warm-up of the directly buried heating pipeline 37, and ensures the safety of the heating pipe network; when not in use, the states of the valves of the steam heating pipe network module are restored at the same time to ensure reliable isolation from the miscellaneous gas system in the power plant and the independence of each system during the warm-up and commissioning of the directly buried heating pipeline 37. [[ID=…]]

[0059] Finally, it should be pointed out that the methods and equipment described in detail above are only examples, and those skilled in the art can modify these examples in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A method for removing condensate from directly buried heating pipelines, characterized in that: including Configure the valves of the directly buried heating pipeline, and set the path for the directly buried heating pipeline to introduce compressed air and discharge condensate unidirectionally; Connect to the miscellaneous gas system to facilitate providing compressed air for the directly buried heating pipeline and providing power for discharging the condensate; Purge with compressed air, and use the compressed air of the miscellaneous gas system to purge the directly buried heating pipeline to discharge the condensate.

2. The method for removing condensate from a directly buried heating pipeline according to claim 1, wherein: The configuration of the valves of the directly buried heating pipeline includes opening the front isolation valve and the drain bypass valve of the directly buried heating pipeline, and simultaneously closing the trap isolation valve and the rear isolation valve of the directly buried heating pipeline.

3. The method for removing condensate from a directly buried heating pipeline according to claim 2, wherein: The connection to the miscellaneous gas system includes connecting the miscellaneous gas system of the power plant to the side isolation valve of the directly buried heating pipeline through a flange connection short pipe.

4. The method for removing condensate from a directly buried heating pipeline according to claim 3, wherein: The purge with compressed air includes slowly opening the side isolation valve of the miscellaneous gas system and the side isolation valve of the directly buried heating pipeline, using the compressed air provided by the miscellaneous gas system to purge the condensate in the directly buried heating pipeline, and monitoring the control valve opening of the drain port of the drain bypass valve to maintain the purge pressure until no accumulated water is discharged.

5. The method for removing condensate from a directly buried heating pipeline according to claim 2, wherein: The drain bypass valve is the condensate discharge port. Closing the trap isolation valve is used to block the drainage function of the trap, and closing the rear isolation valve is used to isolate the rear end of the pipeline to ensure that the compressed air only flows unidirectionally through the drain bypass valve during the purge process.

6. The method for removing condensate from a directly buried heating pipeline according to claim 3, wherein: The pipe diameter of the flange-connected short pipe is DN80 - DN150, and the compressed air flow rate during purging is 700 - 850 m 3 / h; The miscellaneous gas system controls the air flow direction and system isolation through a check valve and an isolation valve.

7. The method for removing condensate from a directly buried heating pipeline according to claim 4, wherein: After the purge is completed, close the side isolation valve of the miscellaneous gas system and the side isolation valve of the directly buried heating pipeline, remove the flange connection short pipe, and restore the initial states of the trap isolation valve and the rear isolation valve to ensure the independent operation of the heating pipeline and the miscellaneous gas system.

8. A system for removing condensate from directly buried heating pipelines, characterized in that: including An air compressor module (1), including an air compressor (12), an air compressor outlet check valve (13), and an air compressor outlet isolation valve (14). The air compressor (12) is connected through the air compressor outlet check valve (13) and the air compressor outlet isolation valve (14). There is at least one group of the air compressor module (1); A compressed air storage tank module (2), connected to the air compressor module (1), including a compressed air storage tank inlet isolation valve (21), a compressed air storage tank (22), and a compressed air storage tank outlet isolation valve (23). The compressed air storage tank inlet isolation valve (21) is connected to the air compressor outlet isolation valve (14); The connection module (4), which is connected to the compressed air storage tank module (2), includes a miscellaneous gas side isolation valve (41), a detachable flange connection short pipe (42), and a heat supply pipeline side isolation valve (43). The detachable flange connection short pipe (42) connects the miscellaneous gas side isolation valve (41) and the heat supply pipeline side isolation valve (43), and the miscellaneous gas side isolation valve (41) is connected to the compressed air storage tank module (2); and, The steam heat supply pipe network module (3), which is connected to the connection module (4), includes a direct-buried heat supply pipeline front isolation valve (31), a direct-buried heat supply pipeline (37), a direct-buried heat supply pipeline steam trap (32), a direct-buried heat supply pipeline steam trap bypass valve (33), and a direct-buried heat supply pipeline steam trap isolation valve (34). The direct-buried heat supply pipeline (37) is connected to the heat supply pipeline side isolation valve (43). The direct-buried heat supply pipeline steam trap (32) is arranged between two direct-buried heat supply pipeline steam trap isolation valves (34). The direct-buried heat supply pipeline steam trap bypass valve (33) and the direct-buried heat supply pipeline steam trap isolation valve (34) are jointly connected to the direct-buried heat supply pipeline (37), and the direct-buried heat supply pipeline front isolation valve (31) is arranged on the direct-buried heat supply pipeline (37).

9. The system for removing condensate from a direct-buried heat supply pipeline according to claim 8, wherein: The air compressor module (1) further includes an air compressor inlet filter screen (11), which is arranged at one end of the air compressor (12) away from the air compressor outlet check valve (13); The compressed air storage tank module (2) further includes a miscellaneous gas main pipe pressure gauge (24), which is arranged between the compressed air storage tank outlet isolation valve (23) and the connection module (4); The steam heat supply pipe network module (3) further includes a steam heat supply pipeline pressure gauge (36), which is arranged on the direct-buried heat supply pipeline (37) on the side of the direct-buried heat supply pipeline front isolation valve (31) away from the connection module (4); The steam heat supply pipe network module (3) further includes a direct-buried heat supply pipeline rear isolation valve (35), which is arranged at one end of the direct-buried heat supply pipeline (37) away from the direct-buried heat supply pipeline front isolation valve (31) where the steam heat supply pipeline pressure gauge (36) is located.

10. The system for removing condensate from a direct-buried heat supply pipeline according to claim 8, wherein: The steam heat supply pipe network module (3) further includes a medium-pressure heat supply steam source (38), a low-pressure heat supply steam source (310), and a medium-pressure heat supply main pipe (39) and a low-pressure heat supply main pipe (311) arranged in parallel. The medium-pressure heat supply main pipe (39) is connected to the medium-pressure heat supply steam source (38), and the low-pressure heat supply main pipe (311) is connected to the low-pressure heat supply steam source (310).

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