CN110592301B - Blast furnace with oxygen-enriched coal injection tuyere and smelting process - Google Patents
Blast furnace with oxygen-enriched coal injection tuyere and smelting process Download PDFInfo
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- CN110592301B CN110592301B CN201910901376.2A CN201910901376A CN110592301B CN 110592301 B CN110592301 B CN 110592301B CN 201910901376 A CN201910901376 A CN 201910901376A CN 110592301 B CN110592301 B CN 110592301B
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B7/00—Blast furnaces
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B7/00—Blast furnaces
- C21B7/10—Cooling; Devices therefor
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B7/00—Blast furnaces
- C21B7/16—Tuyéres
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Abstract
The invention belongs to the technical field of metallurgical equipment, and particularly relates to a blast furnace with an oxygen-enriched coal injection tuyere and a smelting process. The invention provides a blast furnace with an oxygen-enriched coal injection tuyere, which comprises a furnace cover, a furnace body, a furnace belly and a furnace hearth which are sequentially arranged, and a blast furnace tuyere between the furnace belly and the furnace hearth, wherein the blast furnace tuyere comprises a large sleeve, a middle sleeve and a small sleeve which are arranged on the furnace wall of the furnace belly; a cooler is sleeved outside the blowpipe, the inner cavity of the cooler is filled with cooling water, and a plurality of uniformly arranged fins are arranged on the side wall of the cooler; a coil pipe is arranged between the small sleeve and the outer wall of the cooler, and the coil pipe is filled with air at normal temperature and connected with an air pump. The invention forms a structure that the middle sleeve is cooled by water cooling, the small sleeve is cooled by air cooling, and the outer side of the blowpipe at the central position is cooled by water cooling through the three layers of circulating cooling systems arranged in the tuyere, thereby realizing the purposes that the tuyere of the blast furnace can resist high temperature and thermal fatigue, overcome abrasive particle erosion and prolong the service life.
Description
Technical Field
The invention belongs to the technical field of metallurgical equipment, and particularly relates to a blast furnace with an oxygen-enriched coal injection tuyere and a smelting process.
Background
In the steel industry, charging materials from the top of a blast furnace into the furnace for smelting to obtain steel, wherein the arrangement and the structure of a tuyere are one of key components. The device not only directly provides oxygen and coal powder required by blast furnace smelting, but also provides aerodynamic force required for overcoming resistance of a blast furnace charge column, and transfers high-temperature gas containing oxygen, coal powder and the like to the blast furnace. Therefore, the blast furnace tuyere has the characteristics of good conductivity, uniform cooling, high cooling efficiency, compact structure, good wear resistance and the like. The blast furnace tuyere is usually arranged in a furnace wall between a furnace belly and a furnace bottom, the front section of the tuyere extends into the furnace by 500mm, the tuyere is directly eroded by liquid slag iron and seriously abraded by falling hot materials, the tuyere is easy to lose efficacy, and the blast furnace is low in yield if the tuyere is frequently replaced to stop the blast furnace.
The blast furnace tuyere has extremely severe service environment, not only bears the high temperature of more than 1500 ℃, but also bears the scouring of high-temperature iron flow and the abrasion of furnace burden and slag, and is subjected to severe environments such as high temperature, corrosion, thermal fatigue, abrasive particle erosion (wind speed is more than 150 m/s and contains coal powder) and the like, so the service life is short.
Disclosure of Invention
In order to solve the technical problems, the invention provides the blast furnace with the oxygen-enriched coal injection tuyere, and a cooling structure with a middle sleeve for water cooling, a small sleeve for air cooling and a central blowpipe for water cooling is formed by a three-layer circulating cooling system arranged at the tuyere, so that the blast furnace tuyere can resist high temperature and thermal fatigue, overcome abrasive erosion and prolong the service life.
In order to achieve the purpose, the blast furnace provided with the oxygen-enriched coal injection tuyere comprises a furnace cover, a furnace body, a furnace belly and a furnace hearth which are sequentially arranged from top to bottom, wherein a coal gas nozzle is arranged on the furnace body, a slag outlet is arranged on the furnace hearth, the blast furnace tuyere between the furnace belly and the furnace hearth comprises a large sleeve arranged on the furnace wall of the furnace belly, a middle sleeve is sleeved in the large sleeve, a small sleeve is sleeved in the middle sleeve, a blowpipe is arranged at the central position of the small sleeve, and a first water jacket is arranged in the middle sleeve;
a temperature reducer is sleeved outside the blowpipe, the inner cavity of the temperature reducer is filled with cooling water, and a plurality of uniformly arranged fins are arranged on the side wall of the temperature reducer;
and a coil is arranged between the small sleeve and the outer wall of the cooler, and the coil is filled with air at normal temperature.
Furthermore, an inclined included angle is arranged between the fin and the side wall of the inner cavity, and the included angle range is 15-90 degrees.
Further, the included angle ranges from 30 degrees to 60 degrees.
Further, the included angle value is 30 °, 45 °, 50 ° or 60 °.
Further, the coil comprises a front coil and a rear coil, the diameters of the front coil and the rear coil are gradually reduced from large to small.
Further, the diameter ratio of the front coil pipe to the rear coil pipe is 3: 1.
furthermore, the first water jacket is provided with three rectangular holes with cross sections, and the cross section areas of the three rectangular holes are arranged from small to large.
Further, a second water jacket is arranged in the flange of the large sleeve.
Further, the cross section of the second water jacket is rectangular or circular.
The invention also provides a blast furnace smelting process with the oxygen-enriched coal injection tuyere, which comprises the step of using the oxygen-enriched coal injection tuyere;
step 1) opening a furnace cover, feeding a mixture of iron ores and furnace burden in a proper proportion into a furnace body, and then closing the furnace cover;
step 2) circulating water cooling equipment is started, cooling water respectively enters an inner cavity of the cooler and a first water jacket in the middle sleeve, and the coolers in the middle sleeve and the small sleeves realize water cooling circulation;
step 3) opening circulating air cooling equipment, enabling an air pump to enable cold air to enter an inner cavity from an inlet of a cooler, enabling the cold air to flow out from an outlet of the cooler after heat is absorbed, and performing air cooling circulation on a coil pipe between a small sleeve and the outer wall of the cooler through the cold air to achieve the purpose of reducing the internal temperature of the small sleeve, so that the purposes of performing water cooling on the small sleeve, performing air cooling on the small sleeve and performing water cooling on the outer side of a blowing pipe at the central position are achieved, and cooling of water cooling, air cooling and water cooling three-layer circulation cooling is achieved;
step 4) igniting the oxygen-enriched nozzle and the coal powder nozzle after the oxygen-enriched nozzle and the coal powder nozzle are opened simultaneously, so that the fed coal gas, oxygen-enriched oxygen and coal powder are combusted;
step 5) reducing the iron ore in the furnace body and the mixed material of the furnace burden to reach the temperature of 900-;
and 6) opening the tapping hole at certain time after the reduction is finished, and discharging the reduced molten iron.
Compared with the prior art, the invention has the following beneficial effects:
1. the invention prolongs the service life of the tuyere and improves the labor efficiency of smelting;
2. the invention also reasonably uses an air-cooled structure, thereby saving water resources;
3. the invention changes the conventional structure of the tuyere, reduces the frequency of replacing the tuyere and lightens the labor intensity of workers.
Drawings
FIG. 1 is an overall structural view of a blast furnace of the present invention provided with an oxygen-rich coal injection tuyere;
FIG. 2 is a structural sectional view of embodiment 1;
FIG. 3 is a structural sectional view of embodiment 2.
Reference numerals
In the figure, 1-the slag outlet; 2-hearth; 3-tuyere; 30-inner cavity; 31-a fin; 32-blowing pipe; 33-front coil pipe; 34-a flange; 35-large sleeve; 36-a first water jacket; 37-middle sleeve; 38-rear coil pipe; 39-small sleeve; 310-a protective body; 312-a constriction; 313-a temperature reducer; 314 — a second water jacket; 4-furnace bosh; 5-a gas nozzle; 6, a furnace body; 7-furnace mantle.
Detailed Description
The embodiment of the blast furnace with the oxygen-enriched coal injection tuyere according to the present invention will be further described with reference to the following examples. The following examples are only used to illustrate the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby; various changes and modifications may be made by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present invention, and it is intended that all equivalents also fall within the scope of the present invention.
Example 1
As shown in fig. 1-2, the blast furnace with the oxygen-enriched coal injection tuyere of the present invention comprises a furnace mantle 7, a furnace shaft 6, a furnace belly 4 and a furnace hearth 2 which are arranged in sequence from top to bottom, wherein the furnace shaft 6 is provided with a coal gas nozzle 5, the furnace hearth 2 is provided with a slag outlet 1, the blast furnace tuyere 3 between the furnace belly 4 and the furnace hearth 2 is selected from a high-purity red copper material for the blast furnace tuyere 3, the specific structure of the blast furnace tuyere 3 comprises a large sleeve 35 arranged on the furnace wall of the furnace belly 4, a middle sleeve 37 is sleeved in the large sleeve 35, a small sleeve 39 is sleeved in the middle sleeve 37, a blowpipe 32 is arranged at the center position of the small sleeve 39, and a first water jacket 36 is arranged in the middle sleeve 37; the outer side of the blow pipe 32 is sleeved with a cooler 313, the cooler 313 is a structure with a small sleeve 39 and a similar structure and provided with an inner cavity 30, the front end of the cavity 30 is provided with a gradually contracted shrinkage port 12, the front end of the shrinkage port 312 is provided with a protective body 310 with a T structure, the protective body 310 with the T structure plays a role in protecting the blow pipe 32 from being eroded by molten iron and resisting thermal fatigue, the improvement is that the inner cavity 30 of the cooler 313 is filled with cooling water, the side wall of the inner cavity is provided with a plurality of uniformly arranged fins 31, an inclined included angle is arranged between each fin 31 and the side wall of the inner cavity 30, the included angle ranges from 0 degree to 90 degrees. Further, the included angle preferably ranges from 30 ° to 60 °, and more preferably ranges from 30 °, 45 °, 50 °, or 60 °. In this embodiment, the included angle has a value of 30 °. Because the inner cavity 30 is provided with the fins 31 with included angles, the cooling water circulating in the inner cavity 30 can better absorb the heat of the front end part of the small sleeve 39, and the effect of prolonging the service life of the small sleeve 39 is achieved.
The preferred technical scheme, be equipped with the coil pipe between little cover 39 and the cooler 313 outer wall, be full of the air of normal atmospheric temperature in the coil pipe, the air pump will get into the air in little cover 39 and circulate, play the effect that reduces the inside temperature of little cover 39, in order to reach the refrigerated cooling effect of thermally equivalent, the coil pipe includes preceding coil pipe 33 and back coil pipe 38 that the diameter is by big gradual change little, the diameter transform structure of preceding coil pipe 33 and back coil pipe 38 sets up with the structure that little cover 39 diameter is tapered mutually corresponding, the coarse texture of preceding coil pipe 33 is corresponding with the coarse texture of little cover 39, the fine texture of back coil pipe 38 is corresponding with the fine texture of little cover 39, play even endothermic and exothermic effect. In this embodiment, the preferable technical solution is that the diameter ratio of the front coil 33 and the rear coil 38 is selected from 3: 1, which is used to make the temperature inside the small sleeve 39 uniform.
In this embodiment, a preferable technical solution is that the first water jacket 36 is further provided with three structures with rectangular cross sections, and the cross sectional areas of the three rectangular holes are arranged in order from small to large, so as to play a role in uniformly absorbing and releasing heat of the internal temperature of the middle jacket 38.
The invention also provides a blast furnace smelting process using the oxygen-enriched coal injection tuyere, which comprises the following steps:
step 1) opening a furnace bell 7, feeding a mixture of iron ores and furnace burden in a proper proportion into a furnace body 6, and then closing the furnace bell 7;
step 2) circulating water cooling equipment is started, cooling water respectively enters the inner cavity 30 of the cooler 313 and the first water jacket 36 in the middle sleeve 37, and the water cooling circulation is realized by the middle sleeve 37 and the cooler 313 in the small sleeve;
step 3) opening a circulating air cooling device, wherein cold air enters the inner cavity 30 from an inlet of the cooler 313 by the air pump, flows out from an outlet of the cooler 313 after absorbing heat, and performs air cooling circulation on a coil pipe between the small sleeve 39 and the outer wall of the cooler 313 through the cold air so as to achieve the purpose of reducing the temperature inside the small sleeve 39, so that the purposes of performing water cooling on the small sleeve 37, performing air cooling inside the small sleeve 39 and performing water cooling on the outer side of the blowing pipe 32 at the central position are achieved, and cooling of water cooling, air cooling and water cooling three-layer circulation cooling is achieved;
step 4) igniting the oxygen-enriched nozzle and the coal powder nozzle after the oxygen-enriched nozzle and the coal powder nozzle are opened simultaneously, so that the fed coal gas, oxygen-enriched oxygen and coal powder are combusted;
step 5) reducing the iron ore when the temperature of the mixed material of the iron ore and the furnace burden in the material furnace body 6 reaches 900-;
and 6) opening the tapping hole at certain time after the reduction is finished, and discharging the reduced molten iron.
Example 2
As shown in fig. 3, this embodiment is further improved on the basis of embodiment 1, except that: the invention provides a blast furnace with an oxygen-enriched coal injection tuyere, and aims to solve the problems that a flange plate is most easy to collect heat, so that the heat is easily overhigh, and the hidden trouble of failure occurs. According to the invention, the second water jacket 314 is arranged in the flange of the large sleeve 35, and the second water jacket 314 is communicated with a cooling water system and is used for rapidly cooling the flange plate which is most easy to collect heat, so that the purposes of protecting the large sleeve 35, improving the use efficiency of the air port and prolonging the service life of the air port are achieved. In a preferred embodiment, the cross section of the second water jacket 314 is a rectangular or circular structure.
The preferred embodiments and examples of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the embodiments and examples described above, and various changes can be made within the knowledge of those skilled in the art without departing from the concept of the present invention.
Claims (10)
1. A blast furnace with an oxygen-enriched coal injection tuyere comprises a furnace mantle (7), a furnace body (6), a furnace belly (4) and a furnace hearth (2) which are sequentially arranged from top to bottom, wherein a coal gas nozzle (5) is arranged on the furnace body (6), a slag outlet (1) is arranged on the furnace hearth (2), and a blast furnace tuyere (3) is arranged between the furnace belly (4) and the furnace hearth (2), and is characterized in that the blast furnace tuyere (3) comprises a large sleeve (35) arranged on the furnace wall of the furnace belly (4), a middle sleeve (37) is sleeved in the large sleeve (35), a small sleeve (39) is sleeved in the middle sleeve (37), a blowpipe (32) is arranged at the central position of the small sleeve (39), and a first water jacket (36) is arranged in the middle sleeve (37);
a temperature reducer (313) is sleeved outside the blow pipe (32), an inner cavity (30) of the temperature reducer (313) is filled with cooling water, and a plurality of uniformly arranged fins (31) are arranged on the side wall of the temperature reducer;
a coil pipe is arranged between the small sleeve (39) and the outer wall of the cooler (313), and the coil pipe is filled with air at normal temperature.
2. The blast furnace with an oxygen-enriched coal injection tuyere of claim 1, wherein an inclined included angle is formed between the fin (31) and the side wall of the inner cavity (30), and the included angle ranges from 15 ° to 90 °.
3. The blast furnace with an oxygen-enriched coal injection tuyere of claim 2, wherein the included angle ranges from 30 ° to 60 °.
4. The blast furnace with an oxygen-enriched coal injection tuyere of claim 3, wherein the included angle has a value of 30 °, 45 °, 50 ° or 60 °.
5. The blast furnace with an oxygen-enriched coal injection tuyere according to claim 1, wherein the coils comprise a front coil (33) and a rear coil (38) having diameters gradually reduced from large to small.
6. Blast furnace provided with an oxygen-enriched coal injection tuyere according to claim 5, characterized in that the diameter ratio of the front coil (33) and the rear coil (38) is 3: 1.
7. the blast furnace with an oxygen-enriched coal injection tuyere according to claim 1, wherein the first water jacket (36) is provided with three rectangular holes having cross sections, and the cross sectional areas of the three rectangular holes are arranged in the order of increasing from decreasing to increasing.
8. The blast furnace with an oxygen-enriched coal injection tuyere of claim 1, wherein a second water jacket (314) is provided in the flange of the large sleeve (35).
9. The blast furnace provided with an oxygen-enriched coal injection tuyere of claim 8, wherein the cross-section of the second water jacket (314) is rectangular or circular.
10. A smelting process for a blast furnace provided with an oxygen-rich coal injection tuyere of claim 1, characterized in that the smelting process comprises a step of using an oxygen-rich coal injection tuyere,
step 1) opening a furnace cover (7), feeding a mixture of iron ores and furnace charges with a proper proportion into a furnace body (6), and then closing the furnace cover (7);
step 2) circulating water cooling equipment is started, cooling water enters an inner cavity (30) of the cooler (313) and a first water jacket (36) in the middle sleeve (37) respectively, and the water cooling circulation is realized by the middle sleeve (37) and the cooler (313) in the small sleeve;
step 3) opening a circulating air cooling device, wherein cold air enters the inner cavity (30) from an inlet of the cooler (313) by the air pump, flows out from an outlet of the cooler (313) after heat is absorbed, and performs air cooling circulation on a coil pipe between the small sleeve (39) and the outer wall of the cooler (313) through the cold air so as to achieve the purpose of reducing the internal temperature of the small sleeve (39), form the purposes of performing water cooling on the small sleeve (37) firstly, performing air cooling on the small sleeve (39) and performing water cooling on the outer side of a blowing pipe (32) at the central position, and form cooling of three layers of circulating cooling of water cooling, air cooling and water cooling;
step 4) igniting the oxygen-enriched nozzle and the coal powder nozzle after the oxygen-enriched nozzle and the coal powder nozzle are opened simultaneously, so that the fed coal gas, oxygen-enriched oxygen and coal powder are combusted;
step 5) reducing the iron ore by enabling the temperature of the mixed material of the iron ore and the furnace burden in the furnace body (6) to reach 900-;
and 6) opening the tapping hole at certain time after the reduction is finished, and discharging the reduced molten iron.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910901376.2A CN110592301B (en) | 2019-09-23 | 2019-09-23 | Blast furnace with oxygen-enriched coal injection tuyere and smelting process |
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| CN201910901376.2A CN110592301B (en) | 2019-09-23 | 2019-09-23 | Blast furnace with oxygen-enriched coal injection tuyere and smelting process |
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| CN110592301B true CN110592301B (en) | 2020-07-03 |
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Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112522462A (en) * | 2020-11-06 | 2021-03-19 | 刘兰英 | Blast furnace for smelting iron material |
| CN112322814B (en) * | 2020-12-01 | 2022-07-15 | 上大新材料(泰州)研究院有限公司 | System and method for blowing hydrogen-containing gas into blast furnace |
| CN114018058B (en) * | 2022-01-10 | 2022-03-18 | 唐山精研实业有限责任公司 | Composite material oxygen coal spray gun |
| CN114350874B (en) * | 2022-01-12 | 2022-12-30 | 新疆八一钢铁股份有限公司 | Anti-leakage blast furnace air supply device and installation method thereof |
| CN115125343B (en) * | 2022-07-29 | 2023-05-09 | 内蒙古工业大学 | Wear-resistant high-temperature-resistant high-furnace tuyere |
| CN116179779B (en) * | 2023-02-24 | 2024-06-14 | 新疆八一钢铁股份有限公司 | Method for prolonging service life of oxygen tuyere of European smelting furnace and adjustable tuyere assembly |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2109068C1 (en) * | 1991-05-07 | 1998-04-20 | Александр Васильевич Болдырев | Tuyere for blast furnace |
| JPH10121117A (en) * | 1996-10-21 | 1998-05-12 | Nkk Corp | Operation of blast furnace |
| CN202187018U (en) * | 2011-08-29 | 2012-04-11 | 胡遥 | Tiny sleeve for blast-furnace tuyere |
| CN204474703U (en) * | 2015-02-25 | 2015-07-15 | 新兴铸管股份有限公司 | Blast furnace banking air port sealed structure |
| CN209352943U (en) * | 2018-11-24 | 2019-09-06 | 饶平粤兴铜加工有限公司 | Blast furnace welded type tuyere medium sleeve |
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