High-temperature material cooling and steam overheating coupling system and waste heat recovery method

Abstract

The invention relates to the technical field of industrial waste heat recovery and material cooling, and discloses a high-temperature material cooling and steam overheating coupling system and a waste heat recovery method.The high-temperature material cooling and steam overheating coupling system comprises a tube stack type roller waste heat recovery machine, and the tube stack type roller waste heat recovery machine comprises a feeding box, a rotary barrel, a water return pipe, a water inlet pipe, an air inlet, an air outlet and a feeding pipe; a high-temperature material cooling system and a steam superheating system are innovatively coupled, saturated steam is superheated through high-temperature flue gas generated by material cooling, high-quality superheated steam is stably produced on the premise that extra fuel is not consumed, the waste heat quality is fundamentally improved, and the water hammer risk is avoided; the two media of cooling water and cooling air are adopted for synergistic effect, enhanced cooling and gradient waste heat recovery are conducted on high-temperature materials, efficient coupling utilization of energy is achieved, and the overall energy utilization efficiency of the system is remarkably improved.

Description

Technical Field

[0001] This invention belongs to the field of industrial waste heat recovery and material cooling technology, specifically, it relates to a high-temperature material cooling and steam superheating coupling system and waste heat recovery method. Background Technology

[0002] In long-process industrial manufacturing, large quantities of high-temperature solid materials (such as metallurgical slag and steel slag) with temperatures reaching 700-1200℃ are generated. These materials need to be cooled before entering the next process, and the massive amount of high-quality heat energy they carry has extremely high recovery value. Currently, air cooling or water cooling methods are commonly used for cooling.

[0003] Currently, cooling methods such as natural aging cooling, forced air cooling, direct spraying of industrial water, and external spraying of single-cylinder coolers are commonly used. In this process, a large amount of high-quality heat energy carried by the high-temperature material is directly discharged into the atmosphere or wasted, without being effectively converted into a usable waste heat medium. This not only causes huge energy waste and thermal pollution, but also generates secondary waste such as dust-containing flue gas that pollutes the environment.

[0004] For example, a typical process for using air as a cooling medium and recovering waste heat is as follows: ambient air blown in by a cooling fan is used as a cooling medium to exchange heat directly or indirectly with high-temperature materials. The heated high-temperature air (usually above 300°C) is introduced into a waste heat boiler to heat the water in the boiler to generate steam, thereby realizing the recovery of heat energy. However, in order to maintain the temperature of the hot air, the temperature of the high-temperature materials after this process is generally around 350°C, and a large amount of sensible heat is still inside that has not been recovered, which is not convenient for the subsequent transportation and utilization of materials.

[0005] Some technical approaches utilize drum coolers for waste heat recovery. However, drum coolers typically use demineralized water as the sole cooling source. While this indirectly converts the waste heat from high-temperature materials into low-pressure hot water, the direct utilization of this low-pressure hot water is generally of limited value. Steam, on the other hand, is a versatile heat source that can be used directly as a heating medium or as a power generation or driving medium, making it highly valuable. Current technology allows for the treatment of the hot water generated from the aforementioned waste heat, using a steam generation system to produce low-pressure saturated steam for secondary conversion and utilization. However, due to technological limitations, the quality of the saturated steam produced in this process is currently limited, typically being low-pressure saturated steam. Saturated steam is usually not completely dry; it contains tiny droplets. Therefore, during subsequent power generation or when driving a steam turbine, condensation on the turbine blades can cause blade damage. Alternatively, during transport, condensation at the end of the pipeline due to heat loss can lead to water hammer, severely jeopardizing the safe operation of equipment.

[0006] Therefore, there is an urgent need in this field for an innovative system and method that can organically and efficiently couple the cooling process of high-temperature materials with the improvement of steam quality, while realizing the targeted and tiered utilization of thermal energy of different grades, so as to stably produce high-quality steam without requiring or reducing additional energy consumption, and ultimately significantly improve the energy utilization efficiency and economic benefits of the entire industrial process. Summary of the Invention

[0007] To solve the above-mentioned technical problems, the basic concept of the technical solution adopted by the present invention is as follows: A high-temperature material cooling and steam superheating coupling system and waste heat recovery method, including a tube-type drum waste heat recovery machine, wherein the tube-type drum waste heat recovery machine includes a feed box, a rotating cylinder, a return water pipe, a water inlet pipe, an air inlet, an air outlet, and a feed pipe. The rotating cylinder is formed by multiple steel pipes with cooling water flowing inside, which are used to transfer the heat of the high-temperature material to the cooling water through indirect heat exchange, while the material directly exchanges heat with the introduced room temperature air to form high-temperature flue gas. The steam generation system has its inlet connected to the return water pipe of the tubular drum waste heat recovery machine, and is used to receive the heated high-temperature and high-pressure water and generate saturated steam. A steam superheating system includes a modular steam superheater, wherein the tube side of the modular steam superheater is connected to the saturated steam inlet of the steam generation system, and its shell side is connected to the outlet of the tube-type drum waste heat recovery machine; the modular steam superheater is configured to use high-temperature flue gas to superheat saturated steam to generate superheated steam.

[0008] In a preferred embodiment of the present invention, the rotating cylinder of the tube-type drum waste heat recovery machine is provided with a tube wall cylinder inside. The inner wall of the tube wall cylinder is provided with lifting blades and spiral blades. A drive chain is rotatably connected to the outer wall of the rotating cylinder. A drive mechanism is rotatably connected to the end of the drive chain away from the rotating cylinder. The lifting blades are used to lift the material to form a material curtain, and the spiral blades are used to transport the material from the feed end to the discharge end.

[0009] In a preferred embodiment of the present invention, the steam generating system further includes a deoxygenation system, the connection port of which is connected to the steam generating system for replenishing the system with deoxygenated water.

[0010] In a preferred embodiment of the present invention, the steam superheating system includes a flue gas inlet connected to the outer wall of one end of a modular steam superheater, an electric butterfly valve installed on the flue gas inlet, a temperature transmitter installed on one side of the outer wall of the modular steam superheater near the electric butterfly valve, a pipe compensator installed on one side of the outer wall of the flue gas inlet, a saturated steam inlet connected to the outer wall of the modular steam superheater, a superheated steam outlet at the bottom of the modular steam superheater, a flue gas outlet connected to the other end of the modular steam superheater, a first temperature sensor installed on the superheated steam outlet for detecting the superheated steam temperature, and a steam distribution cylinder connected to the superheated steam outlet.

[0011] In a preferred embodiment of the present invention, the modular steam superheater includes a tube sheet and heat transfer tubes.

[0012] In a preferred embodiment of the present invention, the heat transfer tubes are evenly and equidistantly distributed on the tube sheet.

[0013] In a preferred embodiment of the present invention, the steam superheating system is connected to a dust-laden flue gas treatment system through the flue gas outlet. The dust-laden flue gas treatment system is provided with a cyclone dust collector, a water mist sprayer, a bag filter, an induced draft fan, and a chimney installed sequentially along the flue gas flow direction.

[0014] In a preferred embodiment of the present invention, one end of the cyclone dust collector is provided with an inlet, and the bottom end of the cyclone dust collector is connected to and installed with a fine ash unloading machine.

[0015] In a preferred embodiment of the present invention, the water mist sprayer is configured to cool the flue gas and pre-collect dust, so that the flue gas temperature is reduced to the allowable operating temperature range of the bag filter.

[0016] This invention also discloses the method of using a waste heat recovery method coupled with high-temperature material cooling and steam superheating: S1: High-temperature materials are fed into the tubular drum waste heat recovery machine through the feed box; S2: In the tube-type drum waste heat recovery machine, the cooling water inside the rotating drum is used to indirectly exchange heat with the high-temperature material to produce high-temperature and high-pressure water; at the same time, room temperature air is introduced to directly exchange heat with the high-temperature material in a countercurrent manner to produce high-temperature flue gas of about 240-300℃, and the material is discharged after being cooled to about 150℃. S3: The high-temperature and high-pressure water is transported to the steam generation system for pressure reduction and capacity expansion to generate saturated steam; the saturated condensate is mixed with the replenished deoxygenated water and then returned to the tubular drum waste heat recovery machine for circulating heating; S4: The saturated steam and the high-temperature flue gas are introduced together into the modular steam superheater of the steam superheating system, and the saturated steam is superheated into superheated steam by utilizing the waste heat of the flue gas; and the temperature of the superheated steam is monitored by a temperature sensor, and the opening of the regulating valve on the flue gas pipeline is controlled to stabilize the steam temperature. S5: The dust-laden flue gas after heat exchange is introduced into the dust-laden flue gas treatment system. It passes through a cyclone dust collector for coarse dust removal, a water mist sprayer for cooling and pre-dust removal, and a bag filter for fine dust removal. Finally, it is discharged through a chimney by an induced draft fan to meet emission standards.

[0017] Compared with the prior art, the present invention has the following advantages: 1. This invention innovatively couples a high-temperature material cooling system with a steam superheating system, using the high-temperature flue gas generated by the material cooling itself to superheat saturated steam. Without consuming additional fuel, it stably produces high-quality superheated steam, fundamentally improving the quality of waste heat and avoiding the risk of "water hammer". 2. This invention uses the synergistic effect of two media, cooling water and cooling air, to enhance the cooling of high-temperature materials and recover waste heat in stages, thereby achieving efficient coupling and utilization of energy and significantly improving the overall energy utilization efficiency of the system. 3. This invention ensures the stability of superheated steam temperature and improves the reliability of system operation by setting up an automated temperature control loop; 4. This invention integrates a highly efficient dust-laden flue gas treatment system, achieving ultra-low emissions of pollutants and being environmentally friendly.

[0018] The specific embodiments of the present invention will now be described in further detail with reference to the accompanying drawings.

[0019] Attached Figure Description In the attached diagram: Figure 1 This is a schematic diagram of the overall structure of a high-temperature material cooling and steam superheating coupling system and a waste heat recovery method. Figure 2 A schematic diagram of a tubular drum waste heat recovery machine for a high-temperature material cooling and steam superheating coupling system and waste heat recovery method; Figure 3 for Figure 2 AA section view; Figure 4 This is a schematic diagram of the steam superheating system of a high-temperature material cooling and steam superheating coupling system and a waste heat recovery method. Figure 5 A schematic diagram of a single module of a modular steam superheater for a high-temperature material cooling and steam superheating coupling system and waste heat recovery method. Figure 6 for Figure 5 K-direction view; Figure 7 This is a schematic diagram of a dust-laden flue gas treatment system that combines a high-temperature material cooling and steam superheating coupling system with a waste heat recovery method.

[0020] In the diagram: 1. Tubular drum waste heat recovery machine; 11. Feed box; 12. Rotating drum; 121. Tube wall drum; 122. Lifting blades; 123. Spiral blades; 124. Drive chain; 125. Drive mechanism; 13. Return water pipe; 14. Water inlet pipe; 15. Air inlet; 16. Air outlet; 17. Feed pipe; 2. Steam generation system; 3. Deoxygenation system; 4. Steam superheating system; 401. Flue gas inlet; 402. Electric butterfly valve; 403. Temperature transmitter; 404. Pipeline compensator; 405. Saturated steam inlet; 406. Modular steam superheater; 4061. Tube sheet; 4062. Heat transfer tubes; 407. Flue gas outlet; 408. Superheated steam outlet; 409. Temperature sensor; 410. Steam distributor cylinder; 5. Dust-laden flue gas treatment system; 51. Cyclone dust collector; 511. Inlet; 512. Fine ash unloading machine; 52. Water mist sprayer; 53. Bag filter dust collector; 54. Exhaust fan; 55. Chimney; 551. Outlet. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention.

[0022] Example 1: like Figures 1 to 7As shown, the high-temperature material cooling and steam superheating coupling system includes a tubular drum waste heat recovery machine 1. The tubular drum waste heat recovery machine 1 includes a feed box 11, a rotating cylinder 12, a return water pipe 13, an inlet water pipe 14, an air inlet 15, an air outlet 16, and a feed pipe 17. The rotating cylinder 12 is formed by multiple steel pipes internally filled with cooling water, used to transfer the heat of the high-temperature material to the cooling water through indirect heat exchange. Simultaneously, it directly exchanges heat with the material through introduced ambient temperature air to form high-temperature flue gas. A steam generation system 2, whose inlet is connected to the return water pipe 13 of the tubular drum waste heat recovery machine 1, is used to receive the heated high-temperature, high-pressure water and generate saturated steam. A steam superheating system 4 includes a modular steam superheater 406. The tube side of the superheater 406 is connected to the saturated steam inlet of the steam generation system 2, and its shell side is connected to the air outlet 16 of the tube-type drum waste heat recovery machine 1. The modular steam superheater 406 is configured to use high-temperature flue gas to superheat saturated steam to generate superheated steam. The rotating cylinder 12 of the tube-type drum waste heat recovery machine 1 is provided with a tube wall cylinder 121 inside. The inner wall of the tube wall cylinder 121 is provided with lifting blades 122 and spiral blades 123. The outer wall of the rotating cylinder 12 is rotatably connected with a drive chain 124. The end of the drive chain 124 away from the rotating cylinder 12 is rotatably connected with a drive mechanism 125. The lifting blades 122 are used to lift the material to form a material curtain, and the spiral blades 123 are used to transport the material from the feed end to the discharge end.

[0023] Furthermore, the steam generation system 2 also includes a deaeration system 3, whose connection port is connected to the steam generation system 2 for replenishing the system with deaerated water. The steam superheating system 4 includes a flue gas inlet 401 connected to the outer wall of one end of the modular steam superheater 406. An electric butterfly valve 402 is installed on the flue gas inlet 401. A temperature transmitter 403 is installed on the outer wall of the modular steam superheater 406 on one side of the electric butterfly valve 402. A pipe compensator 404 is installed on the outer wall of one side of the flue gas inlet 401. A saturated steam inlet 405 is connected to the outer wall of the modular steam superheater 406. A superheated steam outlet 408 is provided at the bottom of the modular steam superheater 406. A flue gas outlet 407 is connected to the other end of the modular steam superheater 406. A first temperature sensor 409 is installed on the superheated steam outlet 408 for detecting the superheated steam temperature. A steam distribution cylinder 410 is connected to the superheated steam outlet 408.

[0024] Furthermore, the modular steam superheater 406 includes a tube sheet 4061 and heat transfer tubes 4062. The heat transfer tubes 4062 are evenly and equidistantly distributed on the tube sheet 4061, thereby enabling uniform heat transfer and improving thermal conductivity.

[0025] Example 2: The difference between the above embodiments and this embodiment is that: Figures 1 to 7 As shown, a high-temperature material cooling and steam superheating coupling system is provided. The steam superheating system 4 is connected to a dust-laden flue gas treatment system 5 through a flue gas outlet 407. The dust-laden flue gas treatment system 5 is provided with a cyclone dust collector 51, a water mist sprayer 52, a bag filter 53, an induced draft fan 54, and a chimney 55 installed in sequence along the flue gas flow direction.

[0026] Furthermore, one end of the cyclone dust collector 51 is provided with an inlet 511, and the bottom end of the cyclone dust collector 51 is connected to and installed with a fine ash unloading machine 512.

[0027] Furthermore, the water mist sprayer 52 is configured to cool the flue gas and pre-capture dust, reducing the flue gas temperature to within the allowable operating temperature range of the bag filter 53, thereby ensuring that the flue gas can be finely purified by the bag filter 53 and thus discharged into the atmosphere in an environmentally friendly manner.

[0028] The implementation principle of the high-temperature material cooling and steam superheating coupling system and waste heat recovery method in this embodiment is as follows: First, the high-temperature material is fed into the tubular drum waste heat recovery machine 1 through the feed box. Through the metal tube wall of the tubular drum waste heat recovery machine 1, the core high-temperature sensible heat of the material is transferred to the closed-loop cooling water by conduction heat exchange, generating high-temperature and high-pressure water, which is then used to generate saturated steam through the steam generation system 2. This path mainly recovers high-grade heat energy for steam production. At the same time, the intake room-temperature air and the material undergo direct convective heat exchange to generate high-temperature flue gas of 240-300℃. This path recovers the medium and low-temperature sensible heat of the material and uses it for subsequent superheating. Finally, the steam production and superheating processes are coupled in the steam superheating system 4, utilizing the medium and low-temperature flue gas heat that might otherwise be wasted to superheat the self-generated saturated steam into high-quality superheated steam, achieving the goal of treating waste with waste and improving the quality of the final energy product. After the high-temperature material enters the continuously rotating tubular drum waste heat recovery machine 1, it is repeatedly thrown by the lifting blades 122, making full contact with the ambient air supplied through the air inlet 15 for countercurrent heat exchange. The heated air is discharged as high-temperature flue gas from the air outlet 16. At the same time, the high-temperature heat of the material is transferred to the cooling water inside the tube wall 121. The heated high-temperature and high-pressure water enters the steam generation system 2 through the return water pipe 13, where saturated steam is generated through the pressure reduction and expansion principle. The generated saturated steam is extracted and utilized, while the remaining saturated condensate is mixed with the soft water supplemented by the deoxygenation system 3 and pumped back into the drum by the circulating pump through the water inlet pipe 14 for further heating, forming a stable closed-loop cycle that does not require a large amount of water replenishment. The saturated steam generated by the steam generation system 2 and the high-temperature flue gas generated by the tube-type drum waste heat recovery unit 1 are jointly introduced into the modular steam superheater 406. The flue gas flows through the shell side, and the steam flows through the tube side, achieving efficient heat exchange through the bare tube walls. After absorbing the waste heat from the flue gas, the saturated steam's temperature rises to 20-40°C above the saturation temperature, becoming dry, high-quality superheated steam. To ensure stable superheat, the system is equipped with an intelligent control loop: a temperature sensor 409 installed at the superheated steam outlet 408 monitors the temperature in real time and controls the electric butterfly valve 402 on the flue gas inlet pipe. When the steam temperature is too low, the valve is closed to reduce the flue gas flow, forcing the flue gas temperature to rise, thereby enhancing the superheating effect; conversely, the valve is opened wider. This feedback mechanism ensures that the system can output stable superheated steam under different operating conditions. After heat exchange, the dust-laden flue gas, with its temperature reduced to 180-220℃, enters the subsequent dust-laden flue gas treatment system 5. The flue gas passes through a cyclone dust collector 51 to remove coarse particles, then through a water mist sprayer 52 to cool down and capture fine dust, reducing the temperature to within the safe operating range (approximately 150℃) of the bag filter dust collector 53. Finally, the bag filter dust collector 53 performs fine purification, and then the flue gas is introduced into the chimney 55 by the negative pressure of the induced draft fan 54, and finally discharged into the atmosphere through the outlet 551.

Claims

1. A high-temperature material cooling and steam superheating coupling system, characterized in that, The device includes a tubular drum waste heat recovery machine (1), which includes a feed box (11), a rotating drum (12), a return water pipe (13), a water inlet pipe (14), an air inlet (15), an air outlet (16), and a feed pipe (17). The rotating drum (12) is formed by multiple steel pipes with cooling water flowing inside, and is used to transfer the heat of high-temperature materials to the cooling water through indirect heat exchange, while directly exchanging heat with the materials through the introduced room temperature air to form high-temperature flue gas. The steam generation system (2) has its inlet connected to the return water pipe (13) of the tubular drum waste heat recovery machine (1) and is used to receive the heated high-temperature and high-pressure water and generate saturated steam. The steam superheating system (4) includes a modular steam superheater (406), the tube side of which is connected to the saturated steam inlet of the steam generation system (2), and the shell side of which is connected to the outlet (16) of the tube-type drum waste heat recovery machine (1); the modular steam superheater (406) is configured to use high-temperature flue gas to superheat saturated steam to generate superheated steam.

2. The high-temperature material cooling and steam superheating coupling system according to claim 1, characterized in that, The rotating cylinder (1) of the tube-type drum waste heat recovery machine (1) is provided with a tube wall cylinder (121) inside. The inner wall of the tube wall cylinder (121) is provided with lifting blades (122) and spiral blades (123). The outer wall of the rotating cylinder (12) is rotatably connected with a drive chain (124). The end of the drive chain (124) away from the rotating cylinder (12) is rotatably connected with a drive mechanism (125). The lifting blades (122) are used to lift the material to form a material curtain, and the spiral blades (123) are used to transport the material from the feed end to the discharge end.

3. The high-temperature material cooling and steam superheating coupling system according to claim 1, characterized in that, The steam generating system (2) also includes a deoxygenation system (3), whose connection port is connected to the steam generating system (2) for replenishing the system with deoxygenated water.

4. The high-temperature material cooling and steam superheating coupling system according to claim 1, characterized in that, The steam superheating system (4) includes a flue gas inlet (401) connected to the outer wall of one end of a modular steam superheater (406), an electric butterfly valve (402) installed on the flue gas inlet (401), a temperature transmitter (403) installed on the outer wall of the modular steam superheater (406) on one side of the electric butterfly valve (402), a pipe compensator (404) installed on one side of the outer wall of the flue gas inlet (401), a saturated steam inlet (405) connected to the outer wall of the modular steam superheater (406), a superheated steam outlet (408) provided at the bottom of the modular steam superheater (406), a flue gas outlet (407) connected to the other end of the modular steam superheater (406), a first temperature sensor (409) installed on the superheated steam outlet (408) for detecting the superheated steam temperature, and a steam distribution cylinder (410) connected to the superheated steam outlet (408).

5. The high-temperature material cooling and steam superheating coupling system according to claim 4, characterized in that, The modular steam superheater (406) includes a tube sheet (4061) and heat transfer tubes (4062).

6. The high-temperature material cooling and steam superheating coupling system according to claim 5, characterized in that, The heat transfer tubes (4062) are evenly and equidistantly distributed on the tube sheet (4061).

7. The high-temperature material cooling and steam superheating coupling system according to claim 4, characterized in that, The steam superheating system (4) is connected to a dust-laden flue gas treatment system (5) through the flue gas outlet (407). The dust-laden flue gas treatment system (5) is equipped with a cyclone dust collector (51), a water mist sprayer (52), a bag dust collector (53), an induced draft fan (54), and a chimney (55) in sequence along the flue gas flow direction.

8. The high-temperature material cooling and steam superheating coupling system according to claim 7, characterized in that, The cyclone dust collector (51) has an inlet (511) at one end, and a fine ash unloading machine (512) is connected to the bottom end of the cyclone dust collector (51).

9. The high-temperature material cooling and steam superheating coupling system according to claim 7, characterized in that, The water mist sprayer (52) is configured to cool the flue gas and pre-collect dust, so that the flue gas temperature is reduced to the allowable operating temperature range of the bag filter (53).

10. The high-temperature material cooling and steam superheating coupled waste heat recovery method according to claim 1, applied to the high-temperature material cooling and steam superheating coupled system according to any one of claims 1 to 9, wherein the steps of the high-temperature material cooling and steam superheating coupled waste heat recovery method are as follows: S1: High-temperature materials are fed into the tubular drum waste heat recovery machine (1) through the feed box (11); S2: In the tube-type drum waste heat recovery machine (1), the cooling water in the rotating drum (12) is used to indirectly exchange heat with the high-temperature material to produce high-temperature and high-pressure water; at the same time, room temperature air is introduced to directly exchange heat with the high-temperature material in a countercurrent flow to produce high-temperature flue gas of about 240-300℃, and the material is discharged after being cooled to 150℃. S3: The high-temperature and high-pressure water is transported to the steam generation system (2) for depressurization and expansion to generate saturated steam; the saturated condensate is mixed with the supplemented deoxygenated water and then returned to the pipe-type drum waste heat recovery machine (1) for circulating heating; S4: The saturated steam and the high-temperature flue gas are introduced into the modular steam superheater (406) of the steam superheating system (4) to superheat the saturated steam into superheated steam using the waste heat of the flue gas; and the temperature of the superheated steam is monitored by the temperature sensor (409) and the opening of the regulating valve (402) on the flue gas pipeline is controlled to stabilize the steam temperature. S5: The dust-laden flue gas after heat exchange is introduced into the dust-laden flue gas treatment system (5), and after passing through the cyclone dust collector (51) for coarse dust removal, the water mist sprayer (52) for cooling and pre-dust removal, and the bag dust collector (53) for fine dust removal, it is discharged through the chimney (55) by the induced draft fan (54) to meet the standards.

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