Drainage system of dry quenching coke boiler regular blowdown flash tank

Abstract

The utility model discloses a kind of dry quenching boiler periodic blowdown expansion vessel's drainage systems, it is related to dry quenching equipment technical field, the dry quenching boiler periodic blowdown expansion vessel's drainage system provided by the utility model, including water seal device and periodic blowdown expansion vessel, the periodic blowdown expansion vessel top is communicated with boiler top muffler by diffusion exhaust pipe line, the periodic blowdown expansion vessel bottom is communicated with drain line;The import of the water seal device is communicated with the outlet of the drain line, and the outlet of the water seal device is used for drainage;The height of the water seal device is same with the height of the periodic blowdown expansion vessel in reserved water level line, and the outlet of the water seal device is away from the end of drainage end and the highest point of the water seal device is communicated.The dry quenching boiler periodic blowdown expansion vessel's drainage system provided by the utility model can avoid periodic blowdown expansion vessel in blowdown water emptying.

Description

Technical Field

[0001] This utility model relates to the technical field of dry quenching equipment, and in particular to a drainage system for a periodic blowdown expansion tank of a dry quenching boiler. Background Technology

[0002] During the operation of the dry quenching process, the periodic blowdown expansion tank receives not only the blowdown water from the lower header of the boiler, but also the drainage from the boiler drain header, the blowdown water from the continuous blowdown expansion tank, the emergency drainage from the pipeline drain tank, the boiler start-up drain, and the emergency water release from the steam drum.

[0003] Periodic blowdown expansion tanks are used to expand and separate periodic boiler blowdown water. The separated steam and water can be reused or discharged. In dry quenching coke thermal systems, the steam separated from the periodic blowdown expansion tanks in existing technologies is generally discharged after being connected to a silencer at the top of the boiler via an upper pipeline. The blowdown water inside the expansion tank is directly transported to a collection well through a drain header connected at the bottom, cooled, and then discharged. However, this system has significant drawbacks. Because the volume of wastewater inside the expansion tank is dynamic, the total amount of wastewater inside cannot be calculated. Relying on automatic drainage of the wastewater through pipelines, it is extremely easy to empty the tank during the drainage process. If the wastewater is emptied, on the one hand, negative pressure will form inside the tank, allowing air to be drawn into the system, accelerating metal corrosion, and reducing equipment lifespan. On the other hand, emptying the tank will cause it to lose its pressure buffering capacity, leading to violent pressure fluctuations. In severe cases, steam may backflow into the collection well, causing a "shock explosion" and posing a safety hazard. Utility Model Content

[0004] The purpose of this invention is to provide a drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler, so as to solve the problems existing in the prior art and avoid emptying the wastewater in the periodic blowdown expansion tank.

[0005] To achieve the above objectives, this utility model provides the following solution:

[0006] This utility model provides a drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler, comprising:

[0007] The regularly blowdown expansion container is connected to the boiler top silencer via a venting steam pipe at its top, and to a drainage pipe at its bottom.

[0008] A water seal device is provided, wherein the inlet of the water seal device is connected to the outlet of the drainage pipe, and the outlet of the water seal device is used for drainage; the height of the water seal device is the same as the height of the reserved water level line in the periodic sewage expansion container, and the end of the water seal device away from the drainage end is connected to the highest point of the water seal device.

[0009] Preferably, the water seal device is a transfer pipe, with the inlet and outlet of the transfer pipe located at the bottom, and the middle part of the transfer pipe forming the highest point of the water seal device; the inlet of the transfer pipe is connected to the outlet of the drainage pipe, the outlet of the transfer pipe is connected to the main drainage pipe, the main drainage pipe is located below the transfer pipe, and an air hole is provided at the highest point of the transfer pipe.

[0010] Preferably, the water seal device is a transfer pipe, with its inlet and outlet located at the bottom, and the middle of the transfer pipe forming the highest point of the water seal device; both the inlet and outlet of the transfer pipe are connected to the side wall of the drainage pipe; the end of the drainage pipe away from the periodic sewage expansion container is connected to the main drainage pipe, which is located below the transfer pipe; a gate valve is provided on the drainage pipe, located between the inlet and outlet of the transfer pipe; and an air hole is provided at the highest point of the transfer pipe.

[0011] Preferably, the water seal device is a connecting cylinder, the height of which is the same as the height of the reserved water level line in the periodic sewage expansion container, the bottom of the connecting cylinder has an inlet connected to the drainage pipe, and the top of the connecting cylinder has an outlet.

[0012] Preferably, the top of the water seal device is connected to a drain pipe, the top of the drain pipe is connected to the venting steam pipeline, and the connection point between the drain pipe and the venting steam pipeline is located between the periodic blowdown expansion container and the top of the boiler.

[0013] Preferably, the outlet end of the drainage header is connected to a water collection well.

[0014] Preferably, the outlet at the top of the connecting cylinder is connected to a drain header via a connecting pipe, the drain header being located below the connecting cylinder, and an air hole is provided at the top of the adapter cylinder.

[0015] Preferably, the drainage pipe is connected to the end of the connecting pipe near the main drainage pipe via a bypass pipe, and a gate valve is provided on the bypass pipe.

[0016] Preferably, the nominal diameter of the adapter pipe is not less than 150 mm.

[0017] The present invention achieves the following technical advantages over the prior art:

[0018] This invention features a water seal device installed on the drainage pipe of a periodic sewage discharge container. The height of the water seal device is the same as the reserved water level of the periodic sewage discharge expansion container. When the periodic sewage discharge expansion container discharges water, the sewage discharge well's drainage pipe enters the water seal device and then discharges through the outlet connected to the top of the water seal device. When the water level discharged into the periodic sewage discharge expansion container is the same as the height of the water seal device, the water pressure in the periodic sewage discharge expansion container is the same as the water pressure in the water seal device. At this point, natural discharge cannot continue. Therefore, the periodic sewage discharge expansion container always maintains a reserved water level at the same height as the water seal device, preventing negative pressure from forming inside the periodic sewage discharge expansion container. Air is not drawn into the system, reducing metal corrosion and improving equipment lifespan. The reserved water level also gives the periodic sewage discharge expansion container pressure buffering capacity, reducing pressure fluctuations and preventing steam from backflowing into the water collection well, causing a "shock explosion". Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the drainage system layout of the periodic blowdown expansion tank of a dry quenching coke boiler in one or more embodiments of this utility model.

[0021] In the diagram: 1-Regular sewage discharge expansion container, 2-Drainage pipeline, 3-Water seal device, 4-Drainage main pipe, 5-Water collection well, 6-Drainage pipe, 7-Ventilation pipeline, 8-Gate valve. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] The purpose of this invention is to provide a drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler, so as to solve the problems existing in the prior art and avoid emptying the wastewater in the periodic blowdown expansion tank.

[0024] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] In the dry quenching process, the dry quenching boiler and the periodic blowdown expansion tank are existing technologies, and their structure and principles are common knowledge. When the wastewater in the periodic blowdown expansion tank is emptied, on the one hand, negative pressure is created inside the tank, leading to air intake into the system, accelerating metal corrosion, and reducing equipment lifespan. On the other hand, emptying the wastewater causes the expansion tank to lose its pressure buffering capacity, resulting in drastic pressure fluctuations. In severe cases, steam may backflow into the water collection well, causing a shock explosion and posing a safety hazard. The principle of reserving a certain amount of wastewater during the periodic blowdown expansion tank discharge can avoid these defects; however, the wastewater in the expansion tank is dynamically changing, making it difficult to precisely reserve a set amount during blowdown. To solve this problem, this utility model provides a drainage system for the periodic blowdown expansion tank of a dry quenching boiler, such as... Figure 1 As shown, the device includes a water seal device 3 and a periodic blowdown expansion container 1. The top of the periodic blowdown expansion container 1 is connected to the boiler top silencer via a venting and steam discharge pipe 7, and the bottom of the periodic blowdown expansion container 1 is connected to a drain pipe 2. The inlet of the water seal device 3 is connected to the outlet of the drain pipe 2, and the outlet of the water seal device 3 is used for drainage. The height of the water seal device 3 is the same as the height of the reserved water level line inside the periodic blowdown expansion container 1, and the end of the outlet of the water seal device 3 away from the drainage end is connected to the highest point of the water seal device 3. The reserved water level line of this invention is one-third of the total height of the periodic blowdown expansion container 1, that is, the height of the water seal device 3 is approximately set at one-third of the total height of the periodic blowdown expansion container 1. This invention features a water seal device 3 installed on the drainage pipe 2 of the periodic sewage discharge container. The height of the water seal device 3 is the same as the reserved water level of the periodic sewage discharge expansion container 1. When the periodic sewage discharge expansion container 1 discharges water, the sewage discharge well drainage pipe 2 enters the water seal device 3 and then discharges through the outlet connected to the top of the water seal device 3. When the water level discharged into the periodic sewage discharge expansion container 1 is the same as the height of the water seal device 3, the water pressure in the periodic sewage discharge expansion container 1 is the same as the water pressure in the water seal device 3. At this time, natural discharge cannot continue. Therefore, the periodic sewage discharge expansion container 1 always maintains a reserved water level at the same height as the water seal device 3, preventing the formation of negative pressure in the periodic sewage discharge expansion container 1. Air will not be drawn into the system, reducing metal corrosion and improving the service life of the equipment. The reserved water level gives the periodic sewage discharge expansion container 1 a pressure buffering capacity, reducing pressure fluctuations and preventing steam from backflowing into the water collection well 5, which could cause an impact explosion. To prevent the air plug at the top of the water seal device 3 from affecting drainage and siphoning and draining the water out of the periodic sewage expansion container 1, the high point of the water seal device is connected to the venting and exhaust pipe 7 of the periodic sewage expansion container 1 through a drain pipe 6, and the nominal diameter of the drain pipe 6 should not be less than 25mm.

[0026] Example 1

[0027] like Figure 1As shown, the water seal device 3 in this embodiment is a transfer pipe with a nominal diameter of not less than 150mm. The transfer pipe is shaped like an "n", with the inlet and outlet located at the bottom and the middle of the transfer pipe forming the highest point of the water seal device 3. The inlet of the transfer pipe is connected to the outlet of the drainage pipe 2, and the outlet of the transfer pipe is connected to the drainage header 4. The drainage header 4 is located below the transfer pipe. To avoid completely draining the water in the periodic sewage expansion container 1 due to the siphon effect, an air hole is provided at the highest point of the top of the transfer pipe in this embodiment, so that the drainage process will not form a siphon effect. In another embodiment, a removable cover is provided at the air hole. When the air hole is closed with the cover, since the lowest point of the outlet of the water seal device 3 is located below the bottom of the periodic sewage expansion container 1, the sewage in the periodic sewage expansion container 1 can be drained by the siphon effect. In another embodiment, for ease of pipeline layout, the inlet and outlet of the transfer pipe are both connected to the side wall of the drainage pipe 2; the end of the drainage pipe 2 away from the periodic blowdown expansion container 1 is connected to the main drainage pipe 4, which is located below the transfer pipe. The outlet end of the main drainage pipe 4 is connected to a collection well 5, where the wastewater is allowed to settle, cool, and filter before being discharged; a gate valve 8 is provided on the drainage pipe 2, located between the inlet and outlet of the transfer pipe. When the gate valve 8 is closed, this position is completely sealed, allowing for normal drainage and reserving a set height of wastewater in the periodic blowdown expansion container 1; when the boiler is shut down, or when the periodic blowdown expansion container 1 needs cleaning and maintenance, the gate valve 8 can be opened, allowing the wastewater in the periodic blowdown expansion container 1 to be directly discharged into the main drainage pipe 4 through the gate valve 8, thus emptying the wastewater in the periodic blowdown expansion container 1.

[0028] To prevent airlock at the top of the water seal pipe from affecting drainage and siphoning, thus draining all the water from the periodic blowdown expansion container 1, in one embodiment, a drain pipe 6 is connected to the top of the water seal device 3. The top of the drain pipe 6 is connected to the venting steam pipeline 7, which is connected to the outside atmosphere through a silencer on the top of the boiler. This indirectly connects the top of the drain pipe 6 to the external environment, avoiding the siphoning effect at the water seal device 3. Furthermore, the connection point between the drain pipe 6 and the venting steam pipeline 7 is located between the periodic blowdown expansion container 1 and the top of the boiler, and the nominal diameter of the drain pipe 6 should not be less than 25mm. In this embodiment, the venting steam pipeline 7 is connected to the water seal device 3 through the water supply pipe 6, preventing steam from backflowing into the periodic blowdown expansion container 1. Backflowing steam will flow into the water seal device 3 through the connected drain pipe 6, reducing maintenance costs. This invention can maintain a certain water level in the periodic sewage expansion container 1, avoiding the emptying of sewage in the periodic sewage expansion container 1 during the operation of the dry quenching coke thermal system, thereby preventing air backflow, reducing corrosion risk, extending equipment service life, preventing steam backflow in the drainage system, reducing maintenance costs, avoiding uncontrolled pressure fluctuations, and reducing system stability.

[0029] Example 2

[0030] This embodiment is a further improvement based on Embodiment 1. In this embodiment, the water seal device 3 is a connecting cylinder. The height of the connecting cylinder is the same as the height of the reserved water level line in the periodic sewage expansion container 1. The bottom of the connecting cylinder has an inlet connected to the drainage pipe 2, and the top of the connecting cylinder has an outlet. It can also realize the function of reserving a set height of sewage in the periodic sewage expansion container 1 during the sewage discharge process. The outlet at the top of the connecting cylinder is connected to the drainage header 4 through a connecting pipe. The drainage header 4 is located below the connecting cylinder. To avoid the siphon effect, an air hole is opened at the top of the connecting cylinder.

[0031] In one embodiment, the drainage pipe 2 is connected to the end of the connecting pipe near the drainage header 4 via a bypass pipe. A gate valve 8 is provided on the bypass pipe. When the gate valve 8 is opened, the sewage will no longer pass through the connecting cylinder, so the sewage in the periodic sewage expansion container 1 can be completely drained.

[0032] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of ​​this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A drainage system for a periodic blowdown expansion tank of a dry quenching coke boiler, characterized in that: include: The regularly blowdown expansion container is connected to the boiler top silencer via a venting steam pipe at its top, and to a drainage pipe at its bottom. A water seal device is provided, wherein the inlet of the water seal device is connected to the outlet of the drainage pipe, and the outlet of the water seal device is used for drainage; the height of the water seal device is the same as the height of the reserved water level line in the periodic sewage expansion container, and the end of the water seal device away from the drainage end is connected to the highest point of the water seal device.

2. The drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler according to claim 1, characterized in that: The water seal device is a transfer pipe, with its inlet and outlet located at the bottom, and the middle part of the transfer pipe forming the highest point of the water seal device; the inlet of the transfer pipe is connected to the outlet of the drainage pipe, and the outlet of the transfer pipe is connected to the main drainage pipe, which is located below the transfer pipe, and an air hole is provided at the highest point of the transfer pipe.

3. The drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler according to claim 1, characterized in that: The water seal device is a transfer pipe, with its inlet and outlet located at the bottom, and the middle of the transfer pipe forming the highest point of the water seal device; both the inlet and outlet of the transfer pipe are connected to the side wall of the drainage pipe; the end of the drainage pipe away from the periodic sewage expansion container is connected to the main drainage pipe, which is located below the transfer pipe; a gate valve is installed on the drainage pipe, located between the inlet and outlet of the transfer pipe; and an air vent is provided at the highest point of the transfer pipe.

4. The drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler according to claim 1, characterized in that: The water seal device is a connecting cylinder, the height of which is the same as the height of the reserved water level line in the periodic sewage expansion container. The bottom of the connecting cylinder has an inlet that communicates with the drainage pipe, and the top of the connecting cylinder has an outlet.

5. The drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler according to claim 1, characterized in that: The top of the water seal device is connected to a drain pipe, the top of which is connected to the venting steam pipeline, and the connection point between the drain pipe and the venting steam pipeline is located between the periodic blowdown expansion container and the top of the boiler.

6. The drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler according to claim 2 or 3, characterized in that: The outlet end of the drainage main pipe is connected to a water collection well.

7. The drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler according to claim 4, characterized in that: The outlet at the top of the connecting cylinder is connected to a drain header via a connecting pipe. The drain header is located below the connecting cylinder, and an air hole is provided at the top of the connecting cylinder.

8. The drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler according to claim 7, characterized in that: The drainage pipeline is connected to the end of the connecting pipe near the main drainage pipe via a bypass pipe, and a gate valve is provided on the bypass pipe.

9. The drainage system for the periodic blowdown expansion tank of a dry quenching coke boiler according to claim 2 or 3, characterized in that: The nominal diameter of the transfer pipe is not less than 150 mm.

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