Waste heat recovery system applied to combination of granulation and crushing of metallurgical high-temperature slag

Abstract

The utility model discloses a waste heat recovery system applied to metallurgical high-temperature slag granulation and crushing combination. The waste heat recovery system comprises a material processing module, a waste heat recovery processing module and a dry dedusting module, and the waste heat recovery processing module and the dry dedusting module are respectively connected with the material processing module; the material processing module comprises a rolling crushing assembly, an air quenching granulation assembly, a conveying assembly and a rotary heat exchanger; according to the utility model, a rolling crushing process and an air quenching granulation process are combined, molten, semi-molten and solid slag can be crushed at the same time, the crushing efficiency of the high-temperature slag is effectively improved, waste heat in the crushing process is recovered and utilized through the cooperation of the steam pocket, the rotary heat exchanger and the membrane wall structure, and the energy consumption is reduced. And moreover, a large amount of water is not taken in the rolling and crushing process, so that the generation of secondary sewage sludge caused by wet washing is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of metallurgical equipment, and particularly relates to a waste heat recovery system applied to the granulation and crushing combination of high-temperature molten slag in metallurgy. Background Art

[0002] In the production process of the metallurgical industry, there is a large amount of high-temperature molten slag that needs to be crushed and cooled. Due to production and transportation limitations, when the molten slag is sent to the treatment workshop, the molten slag is partially cooled and presents a multi-phase coexistence state of molten slag, semi-molten or even solid state.

[0003] Taking steelmaking slag as an example, the currently more advanced treatment processes are the rolling and heat-insulating process and the air quenching process. Among them, the rolling and heat-insulating process is widely used in iron and steel enterprises because it can adapt to various forms from liquid to solid state. However, effective waste heat recovery is not achieved in the rolling and heat-insulating stages of this process, and water treatment is required during rolling. During the rolling and crushing process, not only a large amount of dust is generated, but also secondary sewage sludge pollution after wet washing is caused. Moreover, mechanical rolling and crushing are relatively rough, and a cumbersome crushing and screening process is still required after rolling and heat-insulating, which requires a long subsequent process and energy consumption.

[0004] The air quenching process is a process that uses high-speed gas to crush molten slag, and can crush molten slag to 1-3 mm at one time. It is currently the fastest and most efficient pretreatment process. However, this process is only applicable to liquid molten slag and is not applicable to semi-molten and solid slag, which accounts for 30-40% of steelmaking slag and still requires other processes for cooperation. Moreover, the air quenching process is limited to spraying and landing in a free space without any waste heat recovery, and the heat resources are not recycled either. Summary of the Invention

[0005] The technical problem to be solved by the utility model is to provide a waste heat recovery system applied to the granulation and crushing combination of high-temperature molten slag in metallurgy, which can combine the rolling and crushing process and the air quenching granulation process to crush high-temperature molten slag and recover the waste heat during the crushing process.

[0006] To solve the above technical problems, the technical solutions adopted by the utility model are as follows.

[0007] A waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, including a material processing module, a waste heat recovery processing module, and a dry dust removal module. The waste heat recovery processing module and the dry dust removal module are respectively connected to the material processing module; the material processing module includes a rolling and crushing assembly, a pneumatic granulation assembly, a conveying assembly, and a rotary heat exchanger; the waste heat recovery processing module includes a steam drum, and the steam drum transports steam through a steam pipeline; the dry dust removal module includes a dry bag filter. One end of the dry bag filter is connected to the main dust removal pipeline, and the other end is connected to a chimney through a blast pipe, and an induced draft fan is arranged on the blast pipe.

[0008] For the above waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, the rolling and crushing assembly includes a slag pot tipping mechanism and a rolling chamber. A rolling bed is arranged at the bottom of the rolling chamber, and a rolling crusher is also arranged above the rolling bed in the rolling chamber. A first hopper is arranged at the bottom of the rolling bed.

[0009] For the above waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, the rolling chamber adopts a membrane wall structure. One end of the steam drum is connected to the water inlet of the membrane wall structure through a second water inlet pipe, and the other side of the steam drum is connected to the water outlet of the membrane wall structure through a second water outlet pipe.

[0010] For the above waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, the rolling chamber is connected to the main dust removal pipeline through a first dust removal branch pipe, and a first dust removal regulating valve is arranged on the first dust removal branch pipe.

[0011] For the above waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, the pneumatic granulation assembly includes a pneumatic granulation chamber, a slag pot tipping mechanism, a steel slag chute, a pneumatic granulation fan, and a pneumatic granulation nozzle. The pneumatic granulation nozzle is located below the steel slag chute and is connected to the pneumatic granulation fan. The spray outlet of the pneumatic granulation nozzle is inclined towards the pneumatic granulation chamber.

[0012] For the above waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, the pneumatic granulation chamber adopts a membrane wall structure. The steam drum is connected to the water inlet of the membrane wall structure through a third water inlet pipe, and the other side of the steam drum is connected to the water outlet of the membrane wall structure through a third water outlet pipe.

[0013] For the above waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, the pneumatic granulation chamber is connected to the main dust removal pipeline through a second dust removal branch pipe, and a second dust removal regulating valve is arranged on the second dust removal branch pipe.

[0014] For the above waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, the conveying assembly includes a high-temperature conveyor, and the high-temperature conveyor is connected to the feed inlet of the rotary heat exchanger.

[0015] The above-mentioned waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, wherein the steam drum is connected to the water inlet of the rotary heat exchanger through a first water inlet pipe, and the steam drum is connected to the water outlet of the rotary heat exchanger through a first water outlet pipe, and a circulation pump is arranged on the first water inlet pipe.

[0016] Due to the adoption of the above technical solutions, the technical progress achieved by the present utility model is as follows.

[0017] The present utility model provides a waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, which combines the rolling crushing process and the air quenching granulation process, and can simultaneously crush molten, semi-molten and solid slag, effectively improving the crushing efficiency of high-temperature molten slag. At the same time, through the cooperation of the steam drum, the rotary heat exchanger and the membrane wall structure, the waste heat in the crushing process is recovered and utilized. Moreover, a large amount of water treatment is not carried out during the rolling crushing process, reducing the generation of secondary sewage sludge caused by wet washing. The present utility model effectively recovers and treats the dust generated during the crushing process by using a dry bag filter, reducing the discharge of environmental pollutants. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a specific structural schematic diagram of the material conveying and waste heat recovery of the present utility model;

[0019] Figure 2 It is a specific structural schematic diagram of the dust treatment of the present utility model.

[0020] Wherein: 1. slag pot tipping mechanism, 2. rolling crusher, 3. rolling chamber, 4. rolling bed, 5. steel slag chute, 6. air quenching fan, 7. air quenching nozzle, 8. air quenching granulation chamber, 9. high-temperature conveyor, 10. rotary heat exchanger, 11. first water inlet pipe, 12. circulation pump, 13. first water outlet pipe, 14. steam drum, 15. steam conveying pipeline, 16. first hopper, 17. second hopper, 18. first water outlet pipe, 19. second water inlet pipe, 20. third water inlet pipe, 21. third water outlet pipe, 22. first dust removal branch pipe, 23. first dust removal regulating valve, 24. second dust removal branch pipe, 25. second dust removal regulating valve, 26. main dust removal pipeline, 27. dry bag filter, 28. induced draft fan, 29. chimney. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] The present utility model will be further described in detail below in conjunction with the drawings and specific embodiments.

[0022] The waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag, as Figures 1 to 2 shown, includes a material processing module, a waste heat recovery processing module, and a dry dust removal module. The waste heat recovery processing module and the dry dust removal module are respectively connected to the material processing module.

[0023] The material processing module includes a rolling and crushing component, an air quenching and granulation component, a conveying component and a rotary heat exchanger 10. The rolling and crushing component is mainly used to crush semi-molten and solid slag with poor fluidity. The air quenching and granulation component is mainly used to process molten slag with good fluidity. The conveying component is mainly used to transport the steel slag after rolling and crushing or air quenching and granulation. The rotary heat exchanger 10 is mainly used to recover the heat of the high-temperature steel slag.

[0024] The rolling and crushing assembly includes a slag pot tilting mechanism 1 and a rolling chamber 3. A rolling bed 4 is arranged at the bottom of the rolling chamber 3. A rolling crusher 2 is also arranged above the rolling bed 4 in the rolling chamber 3. A first drop hopper 16 is arranged at the bottom of the rolling bed 4.

[0025] The slag pot tilting mechanism 1 delivers the semi-molten and solid slag into the rolling chamber 3, and the slag on the rolling bed 4 is rolled and crushed by the rolling crusher 2. The rolled slag is delivered to the conveying assembly through the first dropping hopper 16 for transportation.

[0026] The air quenching granulation assembly includes an air quenching granulation chamber 8, a slag pot tilting mechanism 1, a slag chute 5, an air quenching fan 6, and an air quenching nozzle 7. The air quenching nozzle 7 is located below the slag chute 5 and connected to the air quenching fan 6. The nozzle of the air quenching nozzle 7 is inclined toward the air quenching granulation chamber 8.

[0027] The air quenching and granulating chamber 8 is used to collect the granulated steel slag particles, and a second hopper 17 is provided at the bottom of the air quenching and granulating chamber 8 .

[0028] The slag pot tilting mechanism 1 sends the molten slag into the slag chute 5 for buffering and stabilizing the flow, and then flows out downward. The air quenching fan 6 provides appropriate air volume and pressure for the air quenching nozzle 7, so that the air quenching nozzle 7 can air quench and granulate the slag in the slag chute 5, and then the air quenching granulation chamber 8 collects the granulated slag particles.

[0029] The conveying assembly includes a high-temperature conveyor 9, which is arranged below the first drop hopper 16 and the second drop hopper 17 and connected to the feed port of the rotary heat exchanger 10 to feed the crushed slag into the rotary heat exchanger 10 for heat exchange, so as to recover the heat.

[0030] The waste heat recovery processing module includes a steam drum 14 , and the steam drum 14 transports steam through a steam transport pipeline 15 .

[0031] The drum 14 is connected to the water inlet of the rotary heat exchanger 10 through the first water inlet pipe 11 , and is connected to the water outlet of the rotary heat exchanger 10 through the first water outlet pipe 13 to form a circulation loop. A circulation pump 12 is provided on the first water inlet pipe 11 .

[0032] The water fed into the rotary heat exchanger 10 by the steam drum 14 absorbs the heat of the high-temperature solid steel slag through membrane wall exchange and produces a steam-water mixture, and the steam-water mixture is then sent back into the steam drum 14 through the first water outlet pipe 13.

[0033] The rolling chamber 3 adopts a membrane wall structure. One end of the steam drum 14 is connected to the water inlet of the membrane wall structure through the second water inlet pipe 19, and the other side of the steam drum 14 is connected to the water outlet of the membrane wall structure through the second water outlet pipe 18.

[0034] The air-quenching granulation chamber 8 adopts a membrane wall structure. The steam drum 14 is connected to the water inlet of the membrane wall structure through the third water inlet pipe 20, and the other side of the steam drum 14 is connected to the water outlet of the membrane wall structure through the third water outlet pipe 21. The membrane wall structure can recover the radiant heat during the rolling and crushing process and the air-quenching granulation process, and convert the cooling water output from the steam drum into a steam-water mixture and send it into the steam drum 14 for storage.

[0035] The dry dust removal module includes a dry bag filter 27. One end of the dry bag filter 27 is connected to the main dust removal pipeline 26, and the other end is connected to the chimney 29 through a blast pipe. An induced draft fan 28 is arranged on the blast pipe.

[0036] The rolling chamber 3 is connected to the main dust removal pipeline 26 through the first dust removal branch pipe 22, and a first dust removal regulating valve 23 is arranged on the first dust removal branch pipe 22.

[0037] Since there is no need to spray water during the rolling and crushing process in the rolling chamber 3, dust removal by the dry dust removal method can prevent secondary pollution of sewage and sludge.

[0038] The air-quenching granulation chamber 8 is connected to the main dust removal pipeline 26 through the second dust removal branch pipe 24, and a second dust removal regulating valve 25 is arranged on the second dust removal branch pipe 24.

[0039] During use, during the rolling and crushing process, the slag pot tilting mechanism 1 sends the semi-molten and solid molten slag into the rolling chamber 3 for rolling and crushing. The rolling chamber 3 absorbs the radiant heat of the high-temperature molten slag during the rolling process to form a steam-water mixture and sends it into the steam drum 14. At the same time, the dust generated during the rolling process is collected into the main dust removal pipeline 26 through the first dust removal branch pipe 22, dust is removed by the dry bag filter 27, and then discharged through the chimney 29.

[0040] During the air-quenching granulation process, the slag pot tilting mechanism 1 sends the molten slag into the steel slag chute 5 for buffering and steady flow and then discharges it. The molten slag is air-quenched and granulated by the cooperation of the air-quenching nozzle 7 and the air-quenching fan 6, and the air-quenching granulation chamber 8 collects the air-quenched and granulated particles.

[0041] The wind quenching granulation chamber 8 absorbs the radiant heat of the high-temperature molten slag during the wind quenching granulation process to form a steam-water mixture and sends it into the steam drum 14. At the same time, the generated soot and dust are collected into the total dust removal pipeline 26 through the second dust removal branch pipe 24, dusted by the dry bag filter 27, and then discharged through the chimney 29.

[0042] The crushed steel slag is respectively sent into the high-temperature conveyor 9 through the first hopper 16 and the second hopper 17. The high-temperature conveyor 9 sends the high-temperature molten slag into the rotary heat exchanger 10 for heat exchange and then discharges it through the low-temperature material outlet. At the same time, the steam-water mixture generated during the heat exchange process is sent into the steam drum 14 for collection. The steam drum 14 separates the steam-water mixture and sends the steam through the steam pipeline.

[0043] The utility model provides a waste heat recovery system applied to the granulation and crushing combination of metallurgical high-temperature molten slag. By combining the rolling crushing process and the wind quenching granulation process, it can simultaneously crush the molten, semi-molten, and solid molten slag, effectively improving the crushing efficiency of the high-temperature molten slag. At the same time, through the cooperation of the steam drum, the rotary heat exchanger, and the membrane wall structure, the waste heat during the crushing process is recovered and utilized. Moreover, a large amount of water treatment is not carried out during the rolling crushing process, reducing the generation of secondary sewage sludge caused by wet washing. The utility model effectively recovers and treats the soot and dust generated during the crushing process by using a dry bag filter, reducing the discharge of environmental pollutants.

Claims

1. Waste heat recovery system applied to metallurgical high temperature slag granulation and crushing combination, characterized by: The invention comprises a material processing module, a waste heat recovery processing module and a dry dust removal module, wherein the waste heat recovery processing module and the dry dust removal module are respectively connected to the material processing module; the material processing module comprises a crushing component, an air quenching granulation component, a conveying component and a rotary heat exchanger (10); the waste heat recovery processing module comprises a steam drum (14), and the steam drum (14) transports steam through a steam transport pipeline (15); the dry dust removal module comprises a dry bag dust collector (27), one end of the dry bag dust collector (27) is connected to the main dust removal pipeline (26), and the other end is connected to the chimney (29) through an air supply pipeline.

2. The waste heat recovery system for metallurgical high-temperature slag granulation and crushing combination according to claim 1 is characterized in that: The rolling and crushing assembly comprises a slag pot tilting mechanism (1), a rolling chamber (3), a rolling bed (4) being arranged at the bottom of the rolling chamber (3), a rolling crusher (2) being arranged above the rolling bed (4) in the rolling chamber (3), and a first drop hopper (16) being arranged at the bottom of the rolling bed (4).

3. The waste heat recovery system for metallurgical high-temperature slag granulation and crushing combination according to claim 2 is characterized in that: The rolling chamber (3) adopts a membrane wall structure, one end of the steam drum (14) is connected to the water inlet of the membrane wall structure through a second water inlet pipe (19), and the other side of the steam drum (14) is connected to the water outlet of the membrane wall structure through a second water outlet pipe (18).

4. The waste heat recovery system for metallurgical high-temperature slag granulation and crushing combination according to claim 2 is characterized in that: The rolling chamber (3) is connected to the main dust removal pipeline (26) via a first dust removal branch pipe (22), and a first dust removal regulating valve (23) is provided on the first dust removal branch pipe (22).

5. The waste heat recovery system for metallurgical high-temperature slag granulation and crushing combination according to claim 1 is characterized in that: The air quenching granulation assembly comprises an air quenching granulation chamber (8), a slag pot tilting mechanism (1), a steel slag chute (5), an air quenching fan (6), and an air quenching nozzle (7). The air quenching nozzle (7) is located below the steel slag chute (5) and is connected to the air quenching fan (6). The nozzle of the air quenching nozzle (7) is inclined toward the air quenching granulation chamber (8).

6. The waste heat recovery system for metallurgical high-temperature slag granulation and crushing combination according to claim 5 is characterized in that: The air quenching granulation chamber (8) adopts a membrane wall structure, the steam drum (14) is connected to the water inlet of the membrane wall structure through a third water inlet pipe (20), and the other side of the steam drum (14) is connected to the water outlet of the membrane wall structure through a third water outlet pipe (21).

7. The waste heat recovery system for metallurgical high-temperature slag granulation and crushing combination according to claim 5 is characterized in that: The wind quenching granulation chamber (8) is connected to the main dust removal pipeline (26) via a second dust removal branch pipe (24), and a second dust removal regulating valve (25) is provided on the second dust removal branch pipe (24).

8. The waste heat recovery system for metallurgical high-temperature slag granulation and crushing combination according to claim 1 is characterized in that: The conveying assembly comprises a high-temperature conveyor (9), and the high-temperature conveyor (9) is connected to the feed port of the rotary heat exchanger (10).

9. The waste heat recovery system for metallurgical high-temperature slag granulation and crushing combination according to claim 8, characterized in that: The steam drum (14) is connected to the water inlet of the rotary heat exchanger (10) via a first water inlet pipe (11), the steam drum (14) is connected to the water outlet of the rotary heat exchanger (10) via a first water outlet pipe (13), and a circulating pump (12) is provided on the first water inlet pipe (11).

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