CN112161485B - Method for recycling waste heat of sintering flue gas - Google Patents
Method for recycling waste heat of sintering flue gas Download PDFInfo
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- CN112161485B CN112161485B CN202011010879.XA CN202011010879A CN112161485B CN 112161485 B CN112161485 B CN 112161485B CN 202011010879 A CN202011010879 A CN 202011010879A CN 112161485 B CN112161485 B CN 112161485B
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- flue gas
- sintering
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- 238000005245 sintering Methods 0.000 title claims abstract description 61
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title claims abstract description 57
- 239000003546 flue gas Substances 0.000 title claims abstract description 57
- 239000002918 waste heat Substances 0.000 title claims abstract description 36
- 238000000034 method Methods 0.000 title claims abstract description 35
- 238000004064 recycling Methods 0.000 title claims abstract description 18
- 239000000463 material Substances 0.000 claims abstract description 46
- 239000002912 waste gas Substances 0.000 claims abstract description 33
- 238000002156 mixing Methods 0.000 claims abstract description 31
- 238000010583 slow cooling Methods 0.000 claims abstract description 24
- 238000001816 cooling Methods 0.000 claims description 7
- 238000012216 screening Methods 0.000 claims description 6
- 239000002994 raw material Substances 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 10
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- 239000000203 mixture Substances 0.000 description 5
- 229910052742 iron Inorganic materials 0.000 description 4
- 238000010248 power generation Methods 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000000446 fuel Substances 0.000 description 2
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D17/00—Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases
- F27D17/10—Arrangements for using waste heat
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B1/00—Preliminary treatment of ores or scrap
- C22B1/14—Agglomerating; Briquetting; Binding; Granulating
- C22B1/16—Sintering; Agglomerating
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D13/00—Apparatus for preheating charges; Arrangements for preheating charges
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention relates to a method for recycling sintering flue gas waste heat, and belongs to the technical field of flue gas waste heat utilization. The method comprises the following steps of (1) mixing high-temperature flue gas and slow-cooling waste gas according to the volume ratio of 1-100: 1 ~ 15 mix back and carry out once to preheat 20 ~ 100min against current to the secondary mixing material, continue again with high temperature flue gas and slowly-cooled waste gas according to the volume ratio for 1 ~ 100: 1 ~ 15 mix after carry out the secondary and preheat 10 ~ 60min to the secondary mixing material, be 1 ~ 100 with high temperature flue gas and slowly-cooled waste gas according to the volume ratio at last: 1-15, carrying out tertiary preheating on the secondary mixed material for 5-40 min, and continuously carrying out subsequent processing steps of material distribution and sintering on the preheated secondary mixed material. The invention not only can effectively solve the problem of recycling the waste heat of the sintering flue gas, but also can stabilize the production quality and the yield of the sintering ore, effectively improve the production efficiency of sintering enterprises and increase the ton ore benefit.
Description
Technical Field
The invention relates to a method for recycling sintering flue gas waste heat, and belongs to the technical field of flue gas waste heat utilization.
Background
Sintering is a production process of sintering powdery materials and fine materials into blocks under the condition of incomplete melting. The shape of the sintered ore of the product is irregular porous ore, and the good air permeability of the blast furnace charge column can be ensured. After sintering, ores which are difficult to reduce or easy to pulverize or expand in volume during reduction can be converted into charging materials which are stable in performance and easy to reduce, and a fusing agent required for slagging in iron-making production is added into the sintering materials before the charging materials are put into a furnace, so that not only can moisture and burning loss be removed, but also the number of charging materials can be reduced, and the quality of agglomerated products can be improved.
Under the environment of high price of raw fuel used by the current iron and steel enterprises, the profits of the iron and steel enterprises are continuously reduced. The sintering plant further reduces the sintering production cost under the condition of ensuring the quality of the sintering ore, finally reduces the iron cost, creates benefits for companies, and is an important work component of sintering production. Therefore, it is necessary to reduce the fuel consumption of the sintered ore and to improve the product quality or the yield of the sintered ore.
The waste heat resources of the sintering plant in the iron and steel industry are three: firstly, the sensible heat contained in the high-temperature flue gas waste heat generated in the sintering process accounts for about 15-20% of the total energy consumption of the sintering process; secondly, the temperature of the slowly-cooled waste gas generated in the cooling process is between 100 ℃ and 400 ℃, and the sensible heat of the slowly-cooled waste gas accounts for 28 to 35 percent of the total heat of the energy consumption of the sintering process; and thirdly, waste heat of waste gas at the ore discharging end. Therefore, the sensible heat of the high-temperature flue gas waste heat and the slow cooling waste gas waste heat accounts for about 50% of the total heat expenditure in the sintering process (the development and application of the sintering waste heat utilization technology, the littoral soldier). In the prior art, the utilization of slow cooling waste gas waste heat is to send medium-low temperature flue gas to a waste heat boiler, and by combining a low-temperature waste heat power generation technology, superheated steam and saturated steam generated by the waste heat boiler are used for pushing a turbine power generation unit to do work for power generation, for example, patent application No. 2010101279822, and a technical scheme recorded by a sintering waste heat power generation system and method. However, the medium-low temperature flue gas in the technical scheme is sent to other departments, and the heat of the flue gas is also greatly dissipated in the transmission process, so that how to effectively utilize the flue gas in the department also becomes a difficult problem.
Patent application No. 2019101360145, a hot air sintering waste heat utilization system and a utilization method thereof disclose that after being collected, high temperature flue gas waste heat and slow cooling waste gas return to a draught fan in the sintering process as a part of sintering air volume, or directly sinter as sintering air volume, but only a small part of high temperature flue gas waste heat and slow cooling waste gas can be applied in the sintering process.
Disclosure of Invention
Aiming at the problems and the defects in the prior art, the invention provides a method for recycling the waste heat of sintering flue gas. According to the invention, the high-temperature flue gas waste heat and the slow-cooling waste gas are mixed according to a specific proportion and then the secondary mixed material is preheated, so that the recycling of the sintering flue gas waste heat can be effectively solved, the production quality and the yield of the sintered ore can be stabilized, the production efficiency of a sintering enterprise can be effectively improved, and the ton ore benefit can be increased. The invention is realized by the following technical scheme.
A method for recycling waste heat of sintering flue gas comprises the following steps of (1-100) mixing high-temperature flue gas and slow-cooling waste gas according to a volume ratio: 1 ~ 15 mix back and carry out once to preheat 20 ~ 100min against current to the secondary mixing material, continue again with high temperature flue gas and slowly-cooled waste gas according to the volume ratio for 1 ~ 100: 1 ~ 15 mix after carry out the secondary and preheat 10 ~ 60min to the secondary mixing material, be 1 ~ 100 with high temperature flue gas and slowly-cooled waste gas according to the volume ratio at last: 1-15, carrying out tertiary preheating on the secondary mixed material for 5-40 min, and continuously carrying out subsequent processing steps of material distribution and sintering on the preheated secondary mixed material.
The temperature of the high-temperature flue gas is 50-500 ℃.
The temperature of the slow cooling waste gas is 30-200 ℃.
And the raw materials are subjected to batching, primary mixing, secondary mixing, material distribution, sintering, crushing, screening and cooling treatment in turn in the process of recycling and returning the waste heat of the sintering flue gas.
The technical scheme of the steps of the raw materials sequentially comprising the steps of batching, primary mixing, secondary mixing, distributing, sintering, crushing, screening and cooling is disclosed by application number 2019113408261, namely a comprehensive sintering method of limonite with a large proportion.
The invention has the beneficial effects that: the inventor combines the sintering treatment process studied in advance, mixes the high-temperature flue gas waste heat and the slow cooling waste gas according to a specific proportion and then preheats the secondary mixed material, thereby not only effectively solving the problem of recycling the sintering flue gas waste heat, but also stabilizing the production quality and yield of the sintering ore, effectively improving the production efficiency of sintering enterprises and increasing the ton ore benefit.
Drawings
FIG. 1 is a process flow diagram of the present invention.
Detailed Description
The invention is further described with reference to the following drawings and detailed description.
Example 1
As shown in fig. 1, in the method for recycling the sintering flue gas waste heat, high-temperature flue gas (the temperature of the high-temperature flue gas is 50 ℃) and slow-cooling waste gas (the temperature of the slow-cooling waste gas is 30 ℃) are mixed according to a volume ratio of 1: 15 after mixing, carrying out primary countercurrent preheating on the secondary mixed material for 100min, and then continuing to mix the high-temperature flue gas and the slow-cooling waste gas according to the volume ratio of 1: 10 after mixing, secondarily preheating the secondary mixed material for 60min, and finally, mixing the high-temperature flue gas and the slow-cooling waste gas according to the volume ratio of 1: 2, preheating the secondary mixed material for 40min for three times after mixing, and continuously performing subsequent processing steps of material distribution and sintering on the preheated secondary mixed material.
Firstly, batching is carried out according to the embodiment 1 of the application No. 2019113408261, then the mixture is preheated by the residual heat of the sintering flue gas in the embodiment 1 in the secondary mixing process, and then the subsequent processing steps such as material distribution, sintering, crushing, screening and cooling processes and parameters are consistent with those in the embodiment 1 of the application No. 2019113408261, and finally, the experimental result shows that compared with the experimental result of the embodiment 1 of the application No. 2019113408261, the sintered ore produced by the embodiment is more stable, the drum strength can reach 75%, and the drum strength is higher than that of the sintered ore in the embodiment 1 of the application No. 2019113408261; and the yield is improved by 2 percent compared with 73 percent of the product of application No. 2019113408261.
Example 2
As shown in fig. 1, in the method for recycling the sintering flue gas waste heat, high-temperature flue gas (the temperature of the high-temperature flue gas is 500 ℃) and slow-cooling waste gas (the temperature of the slow-cooling waste gas is 200 ℃) are mixed according to a volume ratio of 100: 15 after mixing, carrying out primary countercurrent preheating on the secondary mixed material for 20min, and then continuously carrying out high-temperature flue gas and slow-cooling waste gas according to the volume ratio of 100: 5 after mixing, secondarily preheating the secondary mixed material for 10min, and finally, mixing the high-temperature flue gas and the slow-cooling waste gas according to the volume ratio of 100: 1, preheating the secondary mixed material for 5min for three times after mixing, and continuously performing subsequent processing steps of material distribution and sintering on the preheated secondary mixed material.
Firstly, batching is carried out according to the embodiment 1 of the application No. 2019113408261, then the mixture is preheated by the residual heat of the sintering flue gas in the embodiment 1 in the secondary mixing process, and then the subsequent processing steps such as material distribution, sintering, crushing, screening and cooling processes and parameters are consistent with those in the embodiment 1 of the application No. 2019113408261, and finally, the experimental result shows that compared with the experimental result of the embodiment 1 of the application No. 2019113408261, the sintered ore produced by the embodiment is more stable, the drum strength can reach 83%, and the drum strength is higher than that of the sintered ore in the embodiment 1 of the application No. 2019113408261; and the yield is improved by 10 percent compared with 73 percent of the product of application No. 2019113408261.
Example 3
As shown in fig. 1, in the method for recycling the sintering flue gas waste heat, the volume ratio of high-temperature flue gas (the temperature of the high-temperature flue gas is 300 ℃) to slow-cooling waste gas (the temperature of the slow-cooling waste gas is 100 ℃) is 50: 8, heating the secondary mixed material for 60min in a countercurrent mode after mixing, and continuously performing subsequent processing steps of material distribution and sintering on the preheated secondary mixed material.
High-temperature flue gas and slow-cooling waste gas are mixed according to the volume ratio of 50: 15 after mixing, carrying out primary countercurrent preheating on the secondary mixed material for 60min, and then continuously carrying out high-temperature flue gas and slow-cooling waste gas according to the volume ratio of 50: 5 after mixing, secondarily preheating the secondary mixed material for 35min, and finally, mixing the high-temperature flue gas and the slow-cooling waste gas according to the volume ratio of 50: 1, preheating the secondary mixed material for three times for 20min after mixing, and continuously performing subsequent processing steps of material distribution and sintering on the preheated secondary mixed material.
Firstly, batching is carried out according to the embodiment 1 of the application No. 2019113408261, then the mixture is preheated by the residual heat of the sintering flue gas in the embodiment 1 in the secondary mixing process, and then the subsequent processing steps such as material distribution, sintering, crushing, screening and cooling processes and parameters are consistent with those in the embodiment 1 of the application No. 2019113408261, and finally, the experimental result shows that compared with the experimental result of the embodiment 1 of the application No. 2019113408261, the sintered ore produced by the embodiment is more stable, the drum strength can reach 80%, and the drum strength is higher than that of the sintered ore in the embodiment 1 of the application No. 2019113408261; and the yield is improved by 7 percent compared with 73 percent of the product of application No. 2019113408261.
While the present invention has been described in detail with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, and various changes can be made without departing from the spirit and scope of the present invention.
Claims (4)
1. A method for recycling waste heat of sintering flue gas is characterized by comprising the following steps: the method comprises the following steps of (1) mixing high-temperature flue gas and slow-cooling waste gas according to the volume ratio of 1-100: 1 ~ 15 mix back and carry out once to preheat 20 ~ 100min against current to the secondary mixing material, continue again with high temperature flue gas and slowly-cooled waste gas according to the volume ratio for 1 ~ 100: 1 ~ 15 mix after carry out the secondary and preheat 10 ~ 60min to the secondary mixing material, be 1 ~ 100 with high temperature flue gas and slowly-cooled waste gas according to the volume ratio at last: 1-15, carrying out tertiary preheating on the secondary mixed material for 5-40 min, and continuously carrying out subsequent processing steps of material distribution and sintering on the preheated secondary mixed material.
2. The method for recycling the waste heat of the sintering flue gas as claimed in claim 1, wherein: the temperature of the high-temperature flue gas is 50-500 ℃.
3. The method for recycling the waste heat of the sintering flue gas as claimed in claim 1, wherein: the temperature of the slow cooling waste gas is 30-200 ℃.
4. The method for recycling the waste heat of the sintering flue gas as claimed in claim 1, wherein: and the raw materials are subjected to batching, primary mixing, secondary mixing, material distribution, sintering, crushing, screening and cooling treatment in turn in the process of recycling and returning the waste heat of the sintering flue gas.
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| CN202011010879.XA CN112161485B (en) | 2020-09-23 | 2020-09-23 | Method for recycling waste heat of sintering flue gas |
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| CN202011010879.XA CN112161485B (en) | 2020-09-23 | 2020-09-23 | Method for recycling waste heat of sintering flue gas |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105283428A (en) * | 2013-04-15 | 2016-01-27 | 霍尔辛姆科技有限公司 | Process and device for cement clinker production |
| JP2017172026A (en) * | 2016-03-25 | 2017-09-28 | 新日鐵住金株式会社 | Method for supplying hydrogen-containing reducing gas to the blast furnace shaft |
| CN111020178A (en) * | 2019-12-23 | 2020-04-17 | 昆明理工大学 | Comprehensive sintering method of large-proportion limonite |
| CN111678350A (en) * | 2020-06-03 | 2020-09-18 | 首钢集团有限公司 | A sintering flue gas cooling sinter system |
-
2020
- 2020-09-23 CN CN202011010879.XA patent/CN112161485B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105283428A (en) * | 2013-04-15 | 2016-01-27 | 霍尔辛姆科技有限公司 | Process and device for cement clinker production |
| JP2017172026A (en) * | 2016-03-25 | 2017-09-28 | 新日鐵住金株式会社 | Method for supplying hydrogen-containing reducing gas to the blast furnace shaft |
| CN111020178A (en) * | 2019-12-23 | 2020-04-17 | 昆明理工大学 | Comprehensive sintering method of large-proportion limonite |
| CN111678350A (en) * | 2020-06-03 | 2020-09-18 | 首钢集团有限公司 | A sintering flue gas cooling sinter system |
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Effective date of registration: 20241024 Address after: 675000 Township Enterprise Park, Chuxiong Development Zone, Chuxiong Yi Autonomous Prefecture, Yunnan Province Patentee after: Chuxiong Piston Pin Co.,Ltd. Country or region after: China Address before: 650093 No. 253, Xuefu Road, Wuhua District, Yunnan, Kunming Patentee before: Kunming University of Science and Technology Country or region before: China |
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