CN112342374A - Method for producing pellet ore by using low-moisture mineral powder - Google Patents
Method for producing pellet ore by using low-moisture mineral powder Download PDFInfo
- Publication number
- CN112342374A CN112342374A CN202011228398.6A CN202011228398A CN112342374A CN 112342374 A CN112342374 A CN 112342374A CN 202011228398 A CN202011228398 A CN 202011228398A CN 112342374 A CN112342374 A CN 112342374A
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- Prior art keywords
- controlling
- moisture
- raw materials
- pellets
- dryer
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- 239000008188 pellet Substances 0.000 title claims abstract description 46
- 239000000843 powder Substances 0.000 title claims abstract description 29
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 24
- 229910052500 inorganic mineral Inorganic materials 0.000 title claims abstract description 18
- 239000011707 mineral Substances 0.000 title claims abstract description 18
- 239000002994 raw material Substances 0.000 claims abstract description 23
- 238000001035 drying Methods 0.000 claims abstract description 16
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000000034 method Methods 0.000 claims abstract description 11
- 238000005453 pelletization Methods 0.000 claims abstract description 9
- 229910052742 iron Inorganic materials 0.000 claims abstract description 7
- 238000002156 mixing Methods 0.000 claims abstract description 7
- 229910000278 bentonite Inorganic materials 0.000 claims abstract description 6
- 239000000440 bentonite Substances 0.000 claims abstract description 6
- SVPXDRXYRYOSEX-UHFFFAOYSA-N bentoquatam Chemical compound O.O=[Si]=O.O=[Al]O[Al]=O SVPXDRXYRYOSEX-UHFFFAOYSA-N 0.000 claims abstract description 6
- 238000010793 Steam injection (oil industry) Methods 0.000 claims abstract description 4
- 238000002485 combustion reaction Methods 0.000 claims abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 21
- 239000000463 material Substances 0.000 claims description 15
- 239000000203 mixture Substances 0.000 claims description 13
- 238000007599 discharging Methods 0.000 claims description 4
- 230000002035 prolonged effect Effects 0.000 claims description 4
- 241001272720 Medialuna californiensis Species 0.000 claims description 3
- 238000009736 wetting Methods 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims 1
- 230000008901 benefit Effects 0.000 abstract description 5
- 229910000805 Pig iron Inorganic materials 0.000 abstract description 2
- 238000009851 ferrous metallurgy Methods 0.000 abstract description 2
- 238000012946 outsourcing Methods 0.000 abstract description 2
- 230000008569 process Effects 0.000 description 4
- 239000007789 gas Substances 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 239000011449 brick Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 239000002253 acid Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
Images
Classifications
-
- 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
- C22B1/24—Binding; Briquetting ; Granulating
- C22B1/2406—Binding; Briquetting ; Granulating pelletizing
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention provides a method for producing pellets by using low-moisture mineral powder, belonging to the field of ferrous metallurgy. The method comprises the following specific steps: 98% of Russian iron fine powder and 2% of bentonite enter a full-automatic batching system for mixing; carrying out steam injection on the mixed raw materials; then drying the mixed raw materials; putting the dried raw materials into a disc pelletizer for pelletizing, controlling the moisture of green pellets to be 8-9%, controlling the granularity to be 8-16 mm, and controlling the falling strength of the green pellets to be not less than 6 times; uniformly distributing the green pellets after pelletizing on a drying bed through a distributing device, controlling the temperature of the drying bed to be 550 +/-50 ℃, controlling the temperature of a combustion chamber to be 1050 +/-50 ℃ by adopting blast furnace gas, and controlling the pressure to be 12-16 kPa. According to the method, the drum strength of the pellets is improved from less than 90% to more than 92%, the daily output is improved by more than 100 tons/seat, the purchase quantity of high-price outsourcing pellets is synchronously reduced, the benefit is generated by 31 ten thousand tons of pig iron per month, the production cost is reduced, and huge benefits are created for enterprises.
Description
Technical Field
The invention relates to a metallurgical pellet and a production process thereof, belonging to the field of ferrous metallurgy.
Background
The main furnace charge structure of the blast furnace in China is high-alkalinity sinter ore added with acid pellet ore, the pellet ore has the advantages of high grade, low porosity, long-term storage and the like, the pellet ore is one of main raw materials for blast furnace ironmaking, the improvement of the pellet ore proportion is a main development direction for optimizing the blast furnace charge structure, and the improvement of the yield and the quality of the pellet ore is of great importance for improving the economic benefit of enterprises.
Building Longxi steel place in northern severe cold area, province inner pelletizing fine powder resource is short, basically, Russian import powder is taken as main material, the transportation route is far away, normal transportation and unloading can be guaranteed after drying and moisture removal in winter, metallurgical pellets are produced according to the conventional technology because the iron ore powder moisture is too low and is 1-2%, the green pellet strength is low, the pellet rotary drum strength is low and is reduced to below 90%, meanwhile, the ore return rate is increased, the finished pellet yield is low, the blast furnace production requirement cannot be met, and the contradiction that the transportation unloading can be guaranteed and the pellet production is difficult occurs in the current northern iron and steel enterprises after the ore powder is dried and dehydrated in winter.
Disclosure of Invention
The invention aims to solve the problems in the prior art and further provides a method for producing pellets by using low-moisture mineral powder.
The purpose of the invention is realized by the following technical scheme:
a method for producing pellets by using low-moisture mineral powder comprises the following specific steps:
the method comprises the following steps: 98% of Russian iron fine powder and 2% of bentonite enter a full-automatic batching system for mixing;
step two: carrying out steam injection on the mixed raw materials, wherein the moisture of the injected raw materials is increased to 4.5% from 2%, and the temperature is increased to 30 ℃ from 5 ℃; then, continuously adding water to the mixture preheated by the steam for wetting, wherein the water content of the mixture reaches 8.5-9%; then, drying the mixed raw materials, wherein the temperature of the dried raw materials is 40-45 ℃, and the moisture of the dried raw materials is 7-7.5%;
step three: putting the dried raw materials into a disc pelletizer for pelletizing, controlling the moisture of green pellets to be 8-9%, controlling the granularity to be 8-16 mm, and controlling the falling strength of the green pellets to be not less than 6 times;
step four: uniformly distributing the green pellets after pelletizing on a drying bed through a distributing device, controlling the temperature of the drying bed to be 550 +/-50 ℃, controlling the temperature of a combustion chamber to be 1050 +/-50 ℃ by adopting blast furnace gas, and controlling the pressure to be 12-16 kPa.
The invention relates to a method for producing pellets by using low-moisture mineral powder, wherein in the second step, a steam pipeline is arranged at one side outside a feeding chute of a dryer and fixed on the feeding chute, a steam outlet at the tail end is arranged at the lower part of a feeding hole of the feeding chute of the dryer, and the steam pressure is 2.5-4 mpa; and a water pipe is arranged on the other side outside the feeding chute of the dryer, and four atomized water nozzles are arranged at the position 1 m away from the feeding hole of the dryer.
The invention relates to a method for producing pellets by using low-moisture mineral powder, wherein the angle of a material lifting plate of a dryer is adjusted from 3.5 degrees to-1.5-2 degrees, and the discharging time of a mixture is prolonged for 2 minutes.
The invention relates to a method for producing pellets by using low-moisture mineral powder, wherein a flame-throwing hole of a dryer is changed into a rectangle from a half moon shape, and the area of each flame-throwing hole is increased by 0.2 square meters.
The invention relates to a method for producing pellets by using low-moisture mineral powder.
The method for producing the pellet by using the low-moisture mineral powder improves the drum strength of the pellet from less than 90 percent to more than 92 percent, improves the daily output by more than 100 tons/seat, synchronously reduces the purchase quantity of high-price outsourcing pellet, generates 30 ten thousand per month in terms of 31 ten thousand tons of pig iron produced per month, reduces the production cost and creates huge benefit for enterprises.
Drawings
Fig. 1 is a structural sketch of a fire nozzle of a dryer in the invention.
Fig. 2 is a schematic sectional view of a dryer according to the present invention.
Fig. 3 is a schematic structural view of a feeding chute of a dryer in the invention.
The reference numbers in the figures are: 1 is a flame jet; 2 is a refractory brick; 3 is a material raising plate; 4 is a steam pipeline; 5 is a water pipe; 6 is an atomized water spray head; and 7 is a feeding chute.
Detailed Description
The invention will be described in further detail below with reference to the accompanying drawings: the present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation is given, but the scope of the present invention is not limited to the following embodiments.
The first embodiment is as follows: referring to fig. 1 to 3, the method for producing pellets using low-moisture mineral powder according to this embodiment includes the following specific steps:
the method comprises the following steps: 98% of Russian iron fine powder and 2% of bentonite enter a full-automatic batching system for mixing;
step two: performing steam injection on the mixed raw materials, and in order to preheat the mixture in advance and increase the temperature of the mixture and accelerate the migration speed of water in the mixture, as shown in fig. 3, a steam pipeline is arranged on one side outside a feeding chute of a dryer and fixed on the chute, a steam outlet at the tail end is arranged at the lower part of a feeding hole of the chute of the dryer, and the steam pressure is 2.5-4 mpa; after the spraying, the moisture of the raw material is increased to 4.5% from 2%, the temperature is increased to 30% from 5 ℃, a water pipe is arranged on the other side outside a feeding chute of the dryer, four atomized water nozzles are arranged at a position 1 m away from a feeding port of the dryer, the mixture preheated by steam is continuously added with water for wetting, and the moisture of the mixture reaches 8.5-9% after the water is added; then, drying the mixed raw materials for 11 minutes; after the raw materials are proportioned in the proportioning chamber, the raw materials enter a dryer to be preheated and moistened by steam at first, water is continuously added for moistening in the process of continuously moving towards a discharge port in the drying process, the moisture of the materials moistened twice exceeds a pelletizing proper value, the processes of uniformly mixing, drying and heating are completed in the residual material flow moving process of the dryer, the temperature of the dried materials is 40-45 ℃, and the moisture of the dried raw materials is 7-7.5%;
step three: putting the dried raw materials into a disc pelletizer for pelletizing, controlling the moisture of green pellets to be 8-9%, controlling the granularity to be 8-16 mm, and controlling the falling strength of the green pellets to be not less than 6 times;
step four: uniformly distributing the green pellets after pelletizing on a drying bed through a distributing device, controlling the temperature of the drying bed to be 550 +/-50 ℃, controlling the temperature of a combustion chamber to be 1050 +/-50 ℃ by adopting blast furnace gas, and controlling the pressure to be 12-16 kPa.
Example two: as shown in fig. 3, in the method for producing pellets using low-moisture mineral powder according to the present embodiment, 4 atomizing water nozzles are added at the inlet of the dryer in the second step, and the atomizing water nozzles are positioned such that the atomized water can be completely sprayed to the material without being sprayed to the empty material area, thereby increasing the moisture content of the russian iron concentrate powder; the exhaust pipe of the outlet of the dryer is additionally provided with the air blower to improve the air displacement and improve the circulating strength of the airflow.
Example three: as shown in fig. 2, in the method for producing pellets using low-moisture mineral powder according to the embodiment, the angle of the material lifting plate of the dryer is adjusted from 3.5 degrees to an interval ranging from-1.5 degrees to-2 degrees, and after the angle is adjusted, the falling direction of part of the material deviates toward the direction of the material inlet in the falling process of the material, so that the material discharging time is delayed, the material discharging time of the mixture is prolonged by 2 minutes, the mixing time of steam condensate and atomized water with the mixture is prolonged, and the mixing effect is improved.
Example four: as shown in fig. 1, in the method for producing pellets by using low-moisture mineral powder according to the embodiment, the flame ports of the dryer are changed from half-moon shape to rectangle shape, the improvement mode is to remove the castable of the original flame port, the original flame port is built by high-alumina refractory bricks, the area of the flame port is increased by reducing the height and increasing the width of the flame port in the original position, the area of each flame port is increased by 0.2 square meter, the waste gas amount and the drying effect are improved, meanwhile, the temperature of the dryer is reduced from 850 ℃ to 750 ℃, the gas consumption is reduced, and the energy use efficiency is improved.
Example five: in the method for producing pellets by using low-moisture mineral powder, a belt scale is adopted for fine powder, a spiral scale is adopted for bentonite in a full-automatic batching system, and a weight batching method is adopted.
The above description is only a preferred embodiment of the present invention, and these embodiments are based on different implementations of the present invention, and the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (5)
1. The method for producing the pellet by using the low-moisture mineral powder is characterized by comprising the following specific steps of:
the method comprises the following steps: 98% of Russian iron fine powder and 2% of bentonite enter a full-automatic batching system for mixing;
step two: carrying out steam injection on the mixed raw materials, wherein the moisture of the injected raw materials is increased to 4.5% from 2%, and the temperature is increased to 30 ℃ from 5 ℃; then, continuously adding water to the mixture preheated by the steam for wetting, wherein the water content of the mixture reaches 8.5-9%; then, drying the mixed raw materials, wherein the temperature of the dried raw materials is 40-45 ℃, and the moisture of the dried raw materials is 7-7.5%;
step three: putting the dried raw materials into a disc pelletizer for pelletizing, controlling the moisture of green pellets to be 8-9%, controlling the particle size to be 8-16 mm, and controlling the falling strength of the green pellets to be more than or equal to 6 times;
step four: uniformly distributing the green pellets on a drying bed through a distributing device, controlling the temperature of the drying bed to be 550 +/-50 ℃, controlling the temperature of a combustion chamber to be 1050 +/-50 ℃ by adopting blast furnace gas, and controlling the pressure to be 12-16 kPa.
2. The method for producing pellets using low-moisture ore fines as set forth in claim 1, wherein in the second step, a steam pipeline (4) is installed outside the feeding chute (7) of the dryer and fixed to the feeding chute (7), and the steam outlet at the end is located below the feeding opening of the feeding chute (7) of the dryer, and the steam pressure is 2.5-4 mpa; a water pipe (5) is arranged on the other side outside a feeding chute (7) of the dryer, and four atomized water nozzles (6) are arranged at a position 1 m away from a feeding hole of the dryer.
3. The method for producing pellet ore by using mineral powder with low water content as claimed in claim 1 or 2, wherein the angle of the material lifting plate of the dryer is adjusted from 3.5 degrees to-1.5 to-2 degrees, and the discharging time of the mixture is prolonged for 2 minutes.
4. The method as claimed in claim 3, wherein the area of each of the plurality of nozzles is increased by 0.2 square meters by changing the shape of half moon of the burner of the dryer into a rectangular shape.
5. The method for producing pellets using low-moisture mineral powder as claimed in claim 1, wherein in the fully automatic batching system, the fine powder is processed by a belt scale and the bentonite is processed by a spiral scale.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011228398.6A CN112342374B (en) | 2020-11-06 | 2020-11-06 | Method for producing pellet ore by using low-moisture mineral powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011228398.6A CN112342374B (en) | 2020-11-06 | 2020-11-06 | Method for producing pellet ore by using low-moisture mineral powder |
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| Publication Number | Publication Date |
|---|---|
| CN112342374A true CN112342374A (en) | 2021-02-09 |
| CN112342374B CN112342374B (en) | 2022-04-01 |
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| CN202011228398.6A Active CN112342374B (en) | 2020-11-06 | 2020-11-06 | Method for producing pellet ore by using low-moisture mineral powder |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102828023A (en) * | 2011-06-14 | 2012-12-19 | 鞍钢股份有限公司 | Pellets with low bentonite content and production method thereof |
| CN105154660A (en) * | 2015-08-20 | 2015-12-16 | 四川德胜集团钒钛有限公司 | Method for producing pellets for blast furnace by means of low-heat-value coal gas |
| CN105331808A (en) * | 2015-11-26 | 2016-02-17 | 辽宁科技大学 | Method for iron ore powder agglomeration |
| CN106834664A (en) * | 2017-01-10 | 2017-06-13 | 太原钢铁(集团)有限公司 | A kind of method for improving hematite flotation powder ballability |
| CN107488784A (en) * | 2017-09-06 | 2017-12-19 | 安徽工业大学 | A kind of blast furnace ironmaking superfluxed pellets and its production method |
| CN107937716A (en) * | 2017-11-02 | 2018-04-20 | 安阳钢铁股份有限公司 | A kind of iron ore pellets raw materials for production preparation method for being conducive to efficient pelletizing |
| CN111733323A (en) * | 2020-07-21 | 2020-10-02 | 张家港宏昌钢板有限公司 | Method for reducing water consumption for pelletizing of iron-containing dust and mud |
-
2020
- 2020-11-06 CN CN202011228398.6A patent/CN112342374B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102828023A (en) * | 2011-06-14 | 2012-12-19 | 鞍钢股份有限公司 | Pellets with low bentonite content and production method thereof |
| CN105154660A (en) * | 2015-08-20 | 2015-12-16 | 四川德胜集团钒钛有限公司 | Method for producing pellets for blast furnace by means of low-heat-value coal gas |
| CN105331808A (en) * | 2015-11-26 | 2016-02-17 | 辽宁科技大学 | Method for iron ore powder agglomeration |
| CN106834664A (en) * | 2017-01-10 | 2017-06-13 | 太原钢铁(集团)有限公司 | A kind of method for improving hematite flotation powder ballability |
| CN107488784A (en) * | 2017-09-06 | 2017-12-19 | 安徽工业大学 | A kind of blast furnace ironmaking superfluxed pellets and its production method |
| CN107937716A (en) * | 2017-11-02 | 2018-04-20 | 安阳钢铁股份有限公司 | A kind of iron ore pellets raw materials for production preparation method for being conducive to efficient pelletizing |
| CN111733323A (en) * | 2020-07-21 | 2020-10-02 | 张家港宏昌钢板有限公司 | Method for reducing water consumption for pelletizing of iron-containing dust and mud |
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Denomination of invention: A method for producing pellets using low moisture mineral powder Granted publication date: 20220401 Pledgee: Agricultural Bank of China Limited Yichun Jinlin Branch Pledgor: Jianlong Xilin Iron and Steel Co.,Ltd. Registration number: Y2024230000009 |