阅读说明：本技术 一种设有富氧喷煤风口的高炉及熔炼工艺 (Blast furnace with oxygen-enriched coal injection tuyere and smelting process ) 是由 佘雪峰 王京彬 刘燕军 于 2019-09-23 设计创作，主要内容包括：本发明属于冶金设备技术领域,具体涉及一种设有富氧喷煤风口的高炉及熔炼工艺。本发明提供的一种设有富氧喷煤风口的高炉,包括顺序设置的炉罩、炉身、炉腹和炉缸,炉腹和炉缸之间的高炉风口,高炉风口包括设置在炉腹炉壁上的大套、中套和小套,小套的中心位置设有吹管,中套内部设有第一水套；吹管外侧套装有降温器,降温器的内腔充满冷却水且侧壁上设有若干均匀排列的翅片；小套和降温器外壁之间设有盘管,盘管内充满常温的空气并与气泵连接。本发明通过在风口内设置的三层循环冷却系统,形成了中套水冷冷却,小套风冷冷却,中心位置的吹管外侧再进行水冷冷却的结构,实现了高炉风口能够耐高温、耐热疲劳、克服磨粒冲蚀和延长使用寿命的目的。(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.)

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, 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 cooling of water cooling on the small sleeve (37), then perform air cooling on the small sleeve (39), and then perform water cooling on the outer side of a blowing pipe (32) at the central position, form cooling of three-layer circulating cooling of water cooling, air cooling and water cooling, and achieve the purpose of saving steelmaking cooling water due to the addition of an air cooling structure, thereby achieving the effect of saving water;

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 coal gas, the oxygen-enriched oxygen and the coal powder are fed into the coal gas burner to be burnt;

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.

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 and 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 a circulating air cooling device, wherein cold air enters the inner cavity from an inlet of the cooler by an air pump, flows out from an outlet of the cooler after absorbing heat, and performs air cooling circulation on a coil pipe between the small sleeve and the outer wall of the cooler through the cold air so as to achieve the purpose of reducing the internal temperature of the small sleeve, form 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, form cooling of water cooling, air cooling and water cooling three-layer circulation cooling, and achieve the purpose of saving steelmaking cooling water due to the addition of an air cooling structure, thereby achieving the effect of saving water;

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 coal gas, the oxygen-enriched oxygen and the coal powder are fed into the coal gas burner to be burnt;

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 to reach 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.