Waste heat recovery mechanism for smoke outlet of dry quenching furnace
By designing a recirculation tube in the waste heat recovery mechanism of the dry coke quenching oven, the water in the waste heat boiler is transported to the water feed preheater, which solves the problem that the water feed preheater may be overheated and damaged during the first operation of the dry coke quenching oven, and achieves the safe operation of the equipment and the extension of the service life.
Patent Information
- Application Number
- CN202421418440.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-20
- Publication Date
- 2025-03-25
- Estimated Expiration
- 2034-06-20
AI Technical Summary
During the first operation of the dry coke quenching oven, the waste heat boiler does not need to be added to water, resulting in no water flowing through the water feed preheater, which may cause overheating and damage to the water feed preheater.
A waste heat recovery mechanism for the dry coke quenching oven smoke exhaust port is designed, and the water in the waste heat boiler is transported to the water feed preheater through the recirculation pipe to prevent overheating and damage from the water feed preheater.
It effectively prevents overheating and damage caused by no water flow, ensuring the normal operation of the equipment and extending the service life.
Smart Images
Figure CN222665770U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of energy saving of dry quenching coke ovens, in particular to a waste heat recovery mechanism for a smoke exhaust port of a dry quenching coke oven. Background Art
[0002] Coke quenching is one of the important links in the coke production process. The quenching of the red hot coke is called coke quenching. There are two ways to quench coke: wet quenching and dry quenching. The great advantages of the dry coke quenching process in energy saving and environmental protection have led to its promotion and broad application prospects. The dry coke quenching uses inert gas as a carrier to achieve the purpose of coke quenching. The red hot coke is in reverse contact with the cold inert gas in the dry quenching furnace for heat exchange. The coke is cooled, and the inert circulating gas with a higher temperature after absorbing the latent heat of the red coke is discharged from the flue of the dry quenching furnace and enters the dry quenching waste heat boiler for heat exchange. The steam generated by the boiler enters the steam turbine to drive the generator to generate electricity. The low-temperature inert gas cooled from the dry quenching waste heat boiler enters the circulating fan and is re-blown into the dry quenching furnace. The low-temperature inert gas cooled from the dry coke quenching waste heat boiler generally needs to be further cooled before it can be re-blown into the dry coke quenching furnace for circulation. Generally, the low-temperature inert gas cooled from the dry coke quenching waste heat boiler is used to preheat the feed water of the waste heat boiler, thereby realizing the utilization of waste heat. However, when the dry coke quenching furnace just starts working, there is a considerable period of time when the waste heat boiler does not need to be added with water, so that no water flows through the feed water preheater, which may cause the feed water preheater to overheat and be damaged. Summary of the invention
[0003] In order to overcome the technical problem of overheating and damage of a feedwater preheater, the utility model provides a waste heat recovery mechanism for a smoke outlet of a dry quenching coke oven.
[0004] The utility model provides a waste heat recovery mechanism for a smoke outlet of a dry quenching coke oven, which adopts the following technical solution:
[0005] A waste heat recovery mechanism for a smoke exhaust port of a dry quenching coke oven comprises a dry quenching coke oven body, a waste heat boiler, a high-temperature flue gas dust removal device, a steam accumulator, a secondary dust collector, a circulating fan, a feed water preheater, a first water pump, a desalted water tank, a recycling pipe and a second water pump, wherein the air outlet of the dry quenching coke oven body is connected to the waste heat boiler pipeline, the high-temperature flue gas dust removal device is arranged on the connecting pipeline between the air outlet of the dry quenching coke oven body and the waste heat boiler, one end of the waste heat boiler is connected to the steam accumulator, the flue gas outlet of the waste heat boiler is connected to the secondary dust collector pipeline, the circulating fan connects the secondary dust collector and the feed water preheater, the feed water preheater is communicated with the air inlet of the dry quenching coke oven body, the feed water preheater is connected to the desalted water tank through the first water pump, the waste heat boiler is connected to the feed water preheater through the second water pump, and the waste heat boiler is connected to the feed water preheater through the recycling pipe.
[0006] By adopting the above technical scheme, the heat energy of the inert circulating gas whose temperature rises after absorbing the heat of red coke is converted into steam by the waste heat boiler and then used for power generation, which not only reduces the emission of exhaust gas and reduces air pollution, but also achieves energy conservation and consumption reduction and comprehensive utilization of resources; when the waste heat boiler does not need to be filled with water during the ignition process, the recirculation pipe can transport the water in the waste heat boiler to the feed water preheater, which can effectively prevent the feed water preheater from overheating and damage due to lack of water flowing.
[0007] Preferably, the waste heat boiler includes a furnace body, a steam drum and an evaporator, the steam drum is arranged above the furnace body, the evaporator is arranged inside the furnace body, the steam drum is connected to the evaporator through a downcomer, the downcomer is arranged outside the furnace body, the steam drum is also connected to the evaporator through an upper connecting pipe, the upper connecting pipe is arranged inside the furnace body, the steam outlet of the steam drum is connected to the steam accumulator, the feed water preheater is connected to the water inlet of the steam drum through two water pump pipes, and the steam drum is connected to the feed water preheater through a recirculation pipe.
[0008] By adopting the above technical scheme, the flue gas passes through the inside of the furnace body, the feed water of the desalted water tank enters the feed water preheater to absorb heat and then enters the steam drum, the steam drum is connected to the evaporator through a downcomer, the downcomer is located outside the furnace body and does not absorb the heat of the flue gas, the steam drum is also connected to the evaporator through an upper connecting pipe, the water in the evaporator absorbs the heat of the flue gas and part of the water turns into steam, the average density of the steam and water mixture in the evaporator is less than the density of the water in the downcomer, and the existence of the density difference between the two forms a water circulation.
[0009] Preferably, a recirculation valve is provided on the recirculation pipe.
[0010] By adopting the above technical solution, a recirculation valve is arranged on the recirculation pipe, so that the opening and closing of the recirculation pipe can be controlled. When the waste heat boiler does not need to be filled with water during the ignition process, the recirculation valve is opened, and the recirculation pipe can transport the water in the steam drum to the feed water preheater, thereby preventing the feed water preheater from overheating and being damaged; when the steam drum starts to be filled with water, the recirculation valve is closed to prevent the water in the feed water preheater from directly entering the steam drum from the recirculation pipe.
[0011] Preferably, the tube bundle of the evaporator is arranged vertically.
[0012] Preferably, a pressure gauge and a water level gauge are provided at the upper end of the steam drum.
[0013] By adopting the above technical solution, by arranging a pressure gauge and a water level gauge at the upper end of the drum, the pressure and water level conditions in the drum can be monitored, and the opening and closing of the recirculation valve can be controlled according to the indication of the water level gauge.
[0014] In summary, the utility model has the following beneficial effects:
[0015] 1. The utility model is a waste heat recovery mechanism for the exhaust port of a dry quenching coke oven. The waste heat boiler converts the heat energy of the inert circulating gas whose temperature rises after absorbing the heat of red coke into steam for power generation, which not only reduces the emission of exhaust gas and air pollution, but also achieves energy conservation and consumption reduction and comprehensive utilization of resources. When the waste heat boiler does not need to be filled with water during the ignition process, the recirculation pipe can transport the water in the waste heat boiler to the feed water preheater, which can effectively prevent the feed water preheater from being damaged by overheating due to lack of water flowing through.
[0016] 2. The utility model is a waste heat recovery mechanism for the exhaust port of a dry quenching coke oven. The flue gas passes through the inside of the furnace body, and the feed water of the desalted water tank enters the feed water preheater to absorb heat and then enters the steam drum. The steam drum is connected to the evaporator through a downcomer. The downcomer is located outside the furnace body and does not absorb the heat of the flue gas. The steam drum is also connected to the evaporator through an upper connecting pipe. The water in the evaporator absorbs the heat of the flue gas and part of the water turns into steam. The average density of the steam and water mixture in the evaporator is less than the density of the water in the downcomer. The existence of the density difference between the two forms a water cycle.
[0017] 3. The utility model is a waste heat recovery mechanism for the exhaust port of a dry quenching coke oven. By setting a recirculation valve on the recirculation pipe, the opening and closing of the recirculation pipe can be controlled. When the waste heat boiler does not need to be filled with water during the ignition process, the recirculation valve is opened, and the recirculation pipe can transport the water in the drum to the feedwater preheater, thereby preventing the feedwater preheater from being overheated and damaged; when the drum starts to be filled with water, the recirculation valve is closed to prevent the water in the feedwater preheater from directly entering the drum from the recirculation pipe. A pressure gauge and a water level gauge are set at the upper end of the drum to monitor the pressure and water level in the drum, and the opening and closing of the recirculation valve can be controlled according to the indication of the water level gauge. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a schematic diagram of a waste heat recovery mechanism for a smoke outlet of a dry quenching coke oven according to the utility model;
[0019] Figure 2 A waste heat boiler and its connection schematic diagram for a waste heat recovery mechanism for a dry quenching coke oven exhaust port;
[0020] Figure 3 This is a schematic diagram of the waste heat boiler and its connections when the recirculation valve is open;
[0021] Figure 4 Schematic diagram of the waste heat boiler and its connections when the recirculation valve is closed.
[0022] Explanation of the reference numerals: 1. CDQ coke oven body; 2. Waste heat boiler; 21. Furnace body; 22. Steam drum; 221. Downcomer; 222. Upper connecting pipeline; 223. Pressure gauge; 224. Water level gauge; 23. Evaporator; 3. High-temperature flue gas dust removal device; 4. Steam accumulator; 5. Secondary dust collector; 6. Circulating fan; 7. Feed water preheater; 8. Water pump 1; 9. Desalted water tank; 10. Recirculation pipe; 101. Recirculation valve; 11. Water pump 2. DETAILED DESCRIPTION
[0023] The following is combined with Figure 1-Figure 4 The utility model is described in further detail.
[0024] This embodiment discloses a waste heat recovery mechanism for a smoke outlet of a dry quenching coke oven. Figure 1-Figure 4, including a dry quenching coke oven body 1, a waste heat boiler 2, a high-temperature flue gas dust removal device 3, a steam accumulator 4, a secondary dust collector 5, a circulating fan 6, a feed water preheater 7, a water pump 8, a desalted water tank 9 and a recirculation pipe 10. In the figure, the open arrows indicate the circulation direction of the inert gas, the closed hollow arrows indicate the circulation direction of the water, and the closed solid arrows indicate the circulation direction of the steam; the dry quenching coke oven body 1 is the main equipment in the dry quenching device. The hot coke and the cold inert gas are in reverse contact in the dry quenching coke oven body 1 for heat exchange to achieve quenching; the waste heat boiler 2 includes a furnace body 21, a steam drum 22 and an evaporator 23. The steam drum 22 is arranged above the furnace body 21, and the evaporator 23 is arranged inside the furnace body 21. The air outlet is connected to the furnace body 21 pipeline, and a high-temperature flue gas dust removal device 3 is provided on the connecting pipeline between the air outlet of the dry coke quenching oven body 1 and the furnace body 21. The inert circulating gas with a higher temperature after absorbing the heat of the red coke is discharged from the air outlet of the dry coke quenching oven body 1, and enters the furnace body 21 after being processed by the high-temperature flue gas dust removal device 3 to exchange heat with the evaporator 23. The steam drum 22 is connected to the evaporator 23 through a downcomer 221 to provide low-temperature water to the evaporator 23 for heat exchange. The downcomer 221 is arranged outside the furnace body 21 and does not absorb the heat of the flue gas. The steam drum 22 is also connected to the evaporator 23 through an upper connecting pipe 222, and the upper connecting pipe 222 is arranged inside the furnace body 21. After the heat exchange, steam is generated in the evaporator 23, and enters the evaporator 23 through the upper connecting pipe 222. The steam enters the drum 22, and the steam outlet of the drum 22 is connected to the steam accumulator 4 to improve the stability of the system and ensure the stability and reliability of the heat and steam supply; the flue gas outlet of the furnace body 21 is connected to the secondary dust collector 5 pipeline to separate the small particles of coke powder in the circulating gas system to achieve the purpose of protecting the circulating fan 6. The circulating fan 6 connects the secondary dust collector 5 and the feed water preheater 7 to send the inert gas after heat exchange and cooling by the waste heat boiler 2 into the feed water preheater 7 for further cooling. The circulating fan 6 not only provides power for the gas circulation, but also can adjust the speed according to the working conditions to adjust the circulating air volume. The feed water preheater 7 is connected to the air inlet of the dry quenching coke oven body 1 to realize the recycling of the gas; the water pump 8 is respectively connected to the feed water preheater 7 by pipeline. The water preheater 7 and the desalted water tank 9, the water inlet of the feed water preheater 7 and the drum 22 are connected through the water pump 11 pipeline, that is, the water pump 18 pumps the water in the desalted water tank 9 to the feed water preheater 7 for preheating treatment, and then the preheated water is pumped into the drum 22 through the water pump 11 to participate in the subsequent heat exchange; the drum 22 and the feed water preheater 7 are connected through the recirculation pipe 10, and the recirculation pipe 10 is provided with a recirculation valve 101, and the recirculation valve 101 can control the opening and closing of the recirculation pipe 10. When the waste heat boiler 2 does not need to be supplied with water during the ignition process, the recirculation valve 101 is opened, and the recirculation pipe 10 can transport the water in the drum 22 to the feed water preheater 7, thereby preventing the feed water preheater 7 from being overheated and damaged;When the drum 22 starts to be filled with water, the recirculation valve 101 is closed to prevent the water in the feedwater preheater 7 from directly entering the drum 22 from the recirculation pipe 10.
[0025] Among them, Figure 1-Figure 4 As shown, the tube bundle of the evaporator 23 is vertically arranged. The vertically arranged tube bundle absorbs the heat of the inert gas inside the furnace body 21. When water absorbs heat, part of the water turns into steam. Since the density of steam is much smaller than that of water, under the effect of the density difference, the mixture of steam and water in the evaporator 23 forms a cycle with the water in the downcomer 221, so that the water in the steam drum 22 enters the evaporator 23. There is no need to rely on a circulating pump to provide power, which makes the operation and maintenance of the device simple. A pressure gauge 223 and a water level gauge 224 are provided at the upper end of the drum 22, which can monitor the pressure and water level conditions in the drum 22, and can also control the opening and closing of the recirculation valve 101 according to the indication of the water level gauge 224. When the waste heat boiler 2 is in the ignition process, the water level in the drum 22 is high and no water is needed. At this time, the recirculation valve 101 is opened, and the recirculation pipe 10 can transport the water in the drum 22 to the feed water preheater 7, thereby preventing the feed water preheater 7 from overheating and being damaged. The water in the drum 22 is converted into steam through heat exchange in the evaporator 23, and the water level gradually decreases. When the water level is lower than a certain set value, the drum 22 starts to be filled with water. At this time, in order to prevent the water in the feed water preheater 7 from directly entering the drum 22 from the recirculation pipe 10, the recirculation valve 101 is closed.
[0026] The above description is only a preferred embodiment of the present invention and does not constitute any other form of limitation to the present invention. Any technician familiar with the profession may use the technical contents disclosed above to change or modify them into equivalent embodiments with equivalent changes for application in other fields. However, any simple modification or equivalent change made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.
Claims
1. A waste heat recovery mechanism for a smoke outlet of a dry quenching coke oven, characterized in that: The invention comprises a dry quenching coke oven body (1), a waste heat boiler (2), a high-temperature flue gas dust removal device (3), a steam accumulator (4), a secondary dust collector (5), a circulating fan (6), a feed water preheater (7), a first water pump (8), a desalted water tank (9), a recirculation pipe (10) and a second water pump (11), wherein the air outlet of the dry quenching coke oven body (1) is connected to a pipeline of the waste heat boiler (2), the high-temperature flue gas dust removal device (3) is arranged on the connecting pipeline between the air outlet of the dry quenching coke oven body (1) and the waste heat boiler (2), and one end of the waste heat boiler (2) is connected to the waste heat boiler (2). The waste heat boiler (2) is connected to a steam accumulator (4), the flue gas outlet of the waste heat boiler (2) is connected to a secondary dust collector (5) pipeline, the circulating fan (6) is connected to the secondary dust collector (5) and a feed water preheater (7), the feed water preheater (7) is communicated with an air inlet of a dry quenching coke oven body (1), the feed water preheater (7) is connected to a desalted water tank (9) via a water pump 1 (8), the waste heat boiler (2) is connected to the feed water preheater (7) via a water pump 2 (11), and the waste heat boiler (2) and the feed water preheater (7) are connected via a recirculation pipe (10).
2. The waste heat recovery mechanism for a smoke outlet of a dry quenching coke oven according to claim 1, characterized in that: The waste heat boiler (2) comprises a furnace body (21), a steam drum (22) and an evaporator (23), wherein the steam drum (22) is arranged above the furnace body (21), the evaporator (23) is arranged inside the furnace body (21), the steam drum (22) and the evaporator (23) are connected via a downcomer (221), the downcomer (221) is arranged outside the furnace body (21), the steam drum (22) and the evaporator (23) are also connected via an upper connecting pipe (222), the upper connecting pipe (222) is arranged inside the furnace body (21), the steam outlet of the steam drum (22) is connected to a steam accumulator (4), the feed water preheater (7) and the water inlet of the steam drum (22) are connected via a water pump second (11) pipe, and the steam drum (22) and the feed water preheater (7) are connected via a recirculation pipe (10).
3. The waste heat recovery mechanism for a smoke outlet of a dry quenching coke oven according to claim 1, characterized in that: The recirculation pipe (10) is provided with a recirculation valve (101).
4. The waste heat recovery mechanism for a smoke outlet of a dry quenching coke oven according to claim 2, characterized in that: The tube bundle of the evaporator (23) is arranged vertically.
5. The waste heat recovery mechanism for a smoke outlet of a dry quenching coke oven according to claim 2, characterized in that: A pressure gauge (223) and a water level gauge (224) are provided at the upper end of the steam drum (22).