CN110484666B - Cold-state device for simulating blast furnace tuyere coal injection - Google Patents
Cold-state device for simulating blast furnace tuyere coal injection Download PDFInfo
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- CN110484666B CN110484666B CN201910696290.0A CN201910696290A CN110484666B CN 110484666 B CN110484666 B CN 110484666B CN 201910696290 A CN201910696290 A CN 201910696290A CN 110484666 B CN110484666 B CN 110484666B
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B5/00—Making pig-iron in the blast furnace
- C21B5/001—Injecting additional fuel or reducing agents
- C21B5/003—Injection of pulverulent coal
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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
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- Y02P10/00—Technologies related to metal processing
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Abstract
The invention provides a cold state coal injection device for simulating a blast furnace tuyere, and belongs to the field of blast furnace ironmaking. The device comprises a compressed air tank, a compressed nitrogen tank, a fluidization tank, a collection tank, a cloth bag dust collector, an air port, a coal gun, a pulverized coal recovery valve, a blast valve, a pulverized coal valve, a feeding valve and a fluidization tank air inlet valve, wherein a transparent material is installed at the front end of the air port, and gypsum is smeared on the inner wall of the air port. The invention can simulate the tuyere coal injection under the condition of air blast, can directly observe the movement track of the coal powder in the tuyere and directly measure the abrasion part and the abrasion degree of the tuyere. In addition, the coal powder can be recycled in the device for many times, and the environment is not polluted.
Description
Technical Field
The invention belongs to the technical field of iron making, and particularly relates to a device for simulating pulverized coal in a blast furnace tuyere in a cold state, which can directly observe the movement track of the pulverized coal in the tuyere and the abrasion condition of the tuyere under the condition of blast.
Background
With the popularization of the oxygen-enriched coal injection technology of the blast furnace, the abrasion of the tuyere small sleeve becomes a common problem of the blast furnace. Generally, the abrasion of the inner wall of the tuyere is caused by the friction of the pulverized coal track on the inner wall of the tuyere, and the reasons for the abrasion include the lance insertion distance and lance insertion angle of a coal lance, or upwarp of the tuyere, deformation of the coal lance and the like. In the actual production process, the temperature of the tuyere area of the blast furnace exceeds 2000 ℃, and even if tuyere shooting or peep-hole observation is used, the reason why the tuyere small sleeve is abraded cannot be directly judged, so that a coal injection test model needs to be established, and the movement track of the coal powder and the abrasion condition of the tuyere small sleeve are observed by adjusting different coal injection parameters.
Most of domestic test devices for simulating the blast furnace tuyere coal injection do not comprise tuyere blast, and the simulated environment is different from that of the actually produced blast furnace. In fact, the hot air velocity of the blast furnace generally exceeds 200m/s, after the pulverized coal is injected into a belly pipe or a tuyere by a coal gun, the motion track of the pulverized coal is greatly influenced by hot air, and if the blast is not considered, the motion track of the pulverized coal cannot be truly reflected. Therefore, it is necessary to establish a coal injection test model with a blower device to study the wear behavior of the tuyere small sleeve.
Disclosure of Invention
The invention aims to provide a device for simulating the movement of coal dust and the abrasion of an air port under the condition of air blowing, aiming at the problem that the movement of the coal dust in the air port cannot be directly observed at present. The device can be used for adjusting different injection parameters, observing the abrasion condition of the tuyere, finding out the root cause of the abrasion of the tuyere, directly observing the movement track of the pulverized coal in the tuyere and measuring the easily abraded part of the tuyere.
In order to realize the purpose, the invention adopts the following technical scheme:
a cold state coal injection device for simulating a blast furnace tuyere comprises a compressed air tank, a cloth bag dust collector, a compressed nitrogen tank, a fluidization tank, a collection tank, a coal gun, a coal powder adding port, a tuyere observation hole, a high-speed camera module with a light source, a coal powder recovery valve, a blast valve, a coal powder valve, a feeding valve and a fluidization tank air inlet valve; the compressed air tank is connected with the air port through a pipeline, and the pipeline is provided with a blast valve; the compressed nitrogen tank is connected with the fluidization tank through a pipeline, and the pipeline is provided with a fluidization tank air inlet valve; the cloth bag collector is connected with the fluidization tank through a pipeline, and a pulverized coal recovery valve is arranged on the pipeline; the upper end of the fluidization tank is provided with a pulverized coal adding port, the fluidization tank is connected with a coal gun through a pipeline, a pulverized coal valve is installed on the pipeline, the coal gun is connected with one end, close to the air inlet, of the side wall of the air port, and the air port is connected with the collection tank.
Furthermore, the tuyere is made of metal, one end of the tuyere, which is close to the air outlet, is provided with an observation port, the observation port is embedded with a wear-resistant transparent material and is used for observing the movement track of the pulverized coal, the length of the transparent material is 1/3-1/2 of the length of the tuyere, and the radian is 10-180 degrees.
Further, plaster is evenly coated on the metal surface of the inner wall of the air port, and the thickness of the plaster layer is 1-5 mm. After the test is finished, the air port is disassembled, and the abrasion part and the abrasion loss of the inner wall of the air port can be directly measured.
Furthermore, a light source and a camera module are arranged on the outer side of the transparent material of the air port, so that the movement track of the pulverized coal can be directly observed and recorded conveniently.
Further, the coal gun is connected with one end of the air inlet on the side wall of the air port through a flange, and the distance between the outlet of the coal gun and the outlet of the air port is 10-200 mm; the included angle between the coal gun and the central line of the air port is 7-15 degrees.
A method for using a device for simulating blast furnace tuyere coal injection in a cold state is to dry 20-100kg of raw coal at the temperature of 105-120 ℃ for 2.5-3 hours; grinding raw coal to 200-mesh coal powder by using a ball mill for later use; adding an anticaking agent into coal dust, wherein 20-50g of the anticaking agent is added into each kilogram of coal dust; installing a tuyere and a coal gun, setting the angle between the tuyere and the coal gun, and setting the distance between the outlet of the coal gun and the outlet of the tuyere; checking each valve and air tightness, opening a feeding valve after safety is correct, filling pulverized coal into a fluidization tank from a pulverized coal adding port, closing the feeding valve, and opening an air inlet valve of the fluidization tank to enable the pressure of the fluidization tank to be more than or equal to 0.5 MPa; opening a blast valve, opening a coal powder valve, starting a high-speed camera module with a light source, opening the coal powder valve and a coal powder recovery valve, starting to spray, wherein the spraying time is 5-6 minutes, the coal powder is sprayed out by a coal gun and enters a bag dust collector through a collection tank, larger coal powder falls into the bottom of the bag dust collector, the coal powder recovery valve at the lower part of the bag dust collector is opened and falls into a fluidization tank for recycling, and gas is filtered by the bag dust collector to reach the emission standard and then is discharged; when the injection is finished, closing the blast valve, the coal powder valve and the coal powder recovery valve, closing the high-speed camera module with the light source, removing the coal gun and the air port, and observing the abrasion condition of the air port by combining the video provided by the high-speed camera module with the light source;
further, the main components of the anticaking agent are as follows: SiO2 is more than or equal to 95 percent, Fe2O3 is less than or equal to 3 percent, Al2O3 is less than or equal to 2 percent, the pulverized coal can be prevented from being damped and agglomerated, and the pulverized coal can be recycled.
The movement of the coal powder in the tuyere is simulated by adjusting the parameters of the coal gun such as angle, insertion depth, coal injection quantity, solid-gas ratio, upwarp degree of the tuyere and the like, and whether the tuyere is abraded or not is analyzed.
The beneficial effects of the invention at least comprise: the pulverized coal is used in the whole test system in a closed and circulating manner, so that dust pollution is reduced; the test device has high automation degree and does not need excessive manual operation; the device has the function of blowing air, and can reflect the movement track of the pulverized coal in the tuyere more truly; the device can be used for researching the movement track of the pulverized coal at the blast furnace tuyere and the abrasion cause of the tuyere small sleeve, has accurate simulation test result and high reliability, and has higher reference to actual blast furnace coal injection.
Drawings
FIG. 1 is a structural diagram of a simulated blast furnace tuyere coal injection device in a cold state;
in fig. 1, the structures represented by the respective reference numerals are as follows: 1-a compressed air tank; 2-bag dust collector; 3-compressed nitrogen tank; 4-a fluidization tank; 5-a collection tank; 6-coal gun; 7-a coal powder adding port; 8-tuyere; 9-a viewing port; 10-high speed camera module with light source; 11-pulverized coal recovery valve; 12-a blast valve; 13-pulverized coal valves; 14-a feed valve; 15-fluidization tank inlet valve.
Detailed Description
Example 1
A cold state coal injection device for simulating a blast furnace tuyere comprises a compressed air tank 1, a cloth bag dust collector 2, a compressed nitrogen tank 3, a fluidization tank 4, a collection tank 5, a coal gun 6, a coal powder adding port 7, a tuyere 8, a tuyere observation hole 9, a high-speed camera module 10 with a light source, a coal powder recovery valve 11, a blast valve 12, a coal powder valve 13, a feeding valve 14 and a fluidization tank air inlet valve 15; the compressed air tank 1 is connected with an air port through a pipeline, and the pipeline is provided with a blast valve 12; the compressed nitrogen tank 3 is connected with the fluidization tank 4 through a pipeline, and the pipeline is provided with a fluidization tank air inlet valve 15; the cloth bag collector 2 is connected with the fluidization tank 4 through a pipeline, and a coal powder recovery valve 11 is arranged on the pipeline; the upper end of the fluidization tank 4 is provided with a pulverized coal adding port 7, the fluidization tank 4 is connected with a coal gun 6 through a pipeline, a pulverized coal valve 13 is arranged on the pipeline, the coal gun 6 is connected with one end, close to an air inlet, of the side wall of an air port 8, and the air port 8 is connected with the collection tank 4; the tuyere 8 is made of steel, one end of the tuyere 8, which is close to the air outlet, is provided with an observation port 9, wear-resistant glass is embedded in the observation port 9, the length of the wear-resistant glass is 1/3 of the length of the tuyere 8, and the radian is 90 degrees; plaster is evenly coated on the metal surface of the inner wall of the air port 8, and the thickness of the plaster layer is 3 mm; and a high-speed camera module 10 with a light source is arranged on the outer side of the transparent material of the air opening 8.
60kg of raw coal is put into a drying oven, dried for 2.5 hours at 105 ℃, put into a ball mill, ground into 200-mesh coal powder for later use, and added with 1.8kg of an anticaking agent. The angle of the tuyere 8 is declined by 5 degrees, the angle of the coal gun 6 is 9 degrees, and the distance between the outlet of the coal gun 6 and the outlet of the tuyere 8 is 100 mm. The valves and the air tightness are checked at the beginning of the test, after the test is safe, the pulverized coal is filled into the fluidization tank 4 from the pulverized coal adding port 7, and the feeding valve 14 is closed. The air inlet valve 15 of the fluidization tank is opened to ensure that the pressure of the fluidization tank 4 reaches 0.5 MPa. Then the blast valve 12 is opened to make the air quantity reach 3000Nm3And h, opening the coal powder valve 13, and seeing the movement track of the coal powder from the observation port 9. The blowing time is 5min, after the pulverized coal blowing is finished, the tuyere 8 is taken down, and the gypsum part in the tuyere 8 is not obviously abraded.
Example 2
A cold state coal injection device for simulating a blast furnace tuyere comprises a compressed air tank 1, a cloth bag dust collector 2, a compressed nitrogen tank 3, a fluidization tank 4, a collection tank 5, a coal gun 6, a coal powder adding port 7, a tuyere 8, a tuyere observation hole 9, a high-speed camera module 10 with a light source, a coal powder recovery valve 11, a blast valve 12, a coal powder valve 13, a feeding valve 14 and a fluidization tank air inlet valve 15; the compressed air tank 1 is connected with an air port through a pipeline, and the pipeline is provided with a blast valve 12; the compressed nitrogen tank 3 is connected with the fluidization tank 4 through a pipeline, and the pipeline is provided with a fluidization tank air inlet valve 15; the cloth bag collector 2 is connected with the fluidization tank 4 through a pipeline, and a coal powder recovery valve 11 is arranged on the pipeline; the upper end of the fluidization tank 4 is provided with a pulverized coal adding port 7, the fluidization tank 4 is connected with a coal gun 6 through a pipeline, a pulverized coal valve 13 is arranged on the pipeline, the coal gun 6 is connected with one end, close to an air inlet, of the side wall of an air port 8, and the air port 8 is connected with the collection tank 4; the tuyere 8 is made of steel, one end of the tuyere 8, which is close to the air outlet, is provided with an observation port 9, wear-resistant glass is embedded in the observation port 9, the length of the wear-resistant glass is 1/3 of the length of the tuyere 8, and the radian is 60 degrees; plaster is evenly coated on the metal surface of the inner wall of the air port 8, and the thickness of the plaster layer is 3 mm; and a high-speed camera module 10 with a light source is arranged on the outer side of the transparent material of the air opening.
60kg of raw coal is put into a drying oven, dried for 2.5 hours at 105 ℃, put into a ball mill, ground into 200-mesh coal powder for later use, and added with 1.8kg of an anticaking agent. To simulate the tuyere 8When the coal powder is tilted, the angle of the tuyere 8 is set to be horizontal, the angle of the coal gun 6 is 9 degrees, and the distance between the outlet of the coal gun 6 and the outlet of the tuyere 8 is 100 mm. The valves and the air tightness are checked at the beginning of the test, after the test is safe, the pulverized coal is filled into the fluidization tank 4 from the pulverized coal adding port 7, and the feeding valve 14 is closed. The air inlet valve 15 of the fluidization tank is opened to ensure that the pressure of the fluidization tank 4 reaches 0.5 MPa. Then the blast valve 12 is opened to make the air quantity reach 3000Nm3And h, opening the coal powder valve 13, and seeing the movement track of the coal powder from the observation port 9. The blowing time is 5min, after the pulverized coal blowing is finished, the air port is taken down, more abrasion of a gypsum part in the air port is found, and the reason of the abrasion is further analyzed by combining with image data provided by the high-speed camera module 10 with a light source.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.
Claims (7)
1. A cold state coal injection device for simulating a blast furnace tuyere comprises a compressed air tank (1), a bag dust collector (2), a compressed nitrogen tank (3), a fluidization tank (4), a collection tank (5), a coal gun (6), a coal powder adding port (7), a tuyere (8), an observation port (9), a high-speed camera module (10) with a light source, a coal powder recovery valve (11), a blast valve (12), a coal powder valve (13), a feeding valve (14) and a fluidization tank air inlet valve (15); the compressed air tank (1) is connected with the air port (8) through a pipeline, and the pipeline is provided with a blast valve (12); the compressed nitrogen tank (3) is connected with the fluidization tank (4) through a pipeline, and the pipeline is provided with a fluidization tank air inlet valve (15); the cloth bag dust collector (2) is connected with the fluidization tank (4) through a pipeline, and the pipeline is provided with a coal dust recovery valve (11); the upper end of the fluidization tank (4) is provided with a pulverized coal adding port (7), the fluidization tank (4) is connected with a coal gun through a pipeline, a pulverized coal valve (13) is installed on the pipeline, the coal gun (6) is connected with one end, close to an air inlet, of the side wall of the air port (8), the air port (8) is connected with the collection tank (5), and gypsum is uniformly coated on the metal surface of the inner wall of the air port (8).
2. The cold state simulated blast furnace tuyere coal injection device according to claim 1, characterized in that: the tuyere (8) is made of metal, one end of the tuyere (8) close to the air outlet is provided with an observation port (9), the observation port (9) is embedded with a transparent material, the length of the transparent material is 1/3-1/2 of the length of the tuyere (8), and the radian is 10-180 degrees.
3. The cold state simulated blast furnace tuyere coal injection device according to claim 1, characterized in that: plaster is evenly coated on the metal surface of the inner wall of the air port (8), and the thickness of the plaster layer is 1-5 mm.
4. The cold state simulated blast furnace tuyere coal injection device according to claim 1, characterized in that: and a high-speed camera module (10) with a light source is arranged on the outer side of the transparent material of the air opening (8).
5. The cold state simulated blast furnace tuyere coal injection device according to claim 1, characterized in that: the coal gun (6) is connected with one end, close to the air inlet, of the side wall of the air port (8) through a flange, and the distance between the outlet of the coal gun (6) and the outlet of the air port (8) is 10-200 mm; the included angle between the coal gun (6) and the central line of the tuyere (8) is 7-15 degrees.
6. The use method of the cold-state simulated blast furnace tuyere coal injection device of any one of claims 1 to 5, comprising the following steps of:
(1) drying 20-100kg of raw coal at the temperature of 105-120 ℃ for 2.5-3 hours;
(2) grinding raw coal into 200-mesh coal powder for later use;
(3) adding an anticaking agent into coal dust, wherein 20-50g of the anticaking agent is added into each kilogram of coal dust;
(4) installing an air port (8) and a coal gun (6), setting the angle between the air port (8) and the coal gun (6), and setting the distance between the outlet of the coal gun (6) and the outlet of the air port (8);
(5) checking each valve and air tightness, opening a feeding valve (14) after safety is correct, filling pulverized coal into a fluidization tank (4) from a pulverized coal adding port (7), closing the feeding valve (14), and opening a fluidization tank air inlet valve (15) to ensure that the pressure of the fluidization tank (4) is more than or equal to 0.5 MPa;
(6) starting an air blowing valve (12), starting a high-speed camera module (10) with a light source, opening a coal powder recovery valve (11) and a coal powder valve (13), and starting to blow for 5-6 minutes;
(7) and closing the blast valve (12), the coal powder valve (13) and the coal powder recovery valve (11), closing the high-speed camera module (10) with the light source, removing the coal gun (6) and the air port (8), and observing the abrasion condition of the air port by combining the video provided by the high-speed camera module (10) with the light source.
7. The use method of the device for simulating the coal injection at the blast furnace tuyere in the cold state according to claim 6, is characterized in that: the main components of the anticaking agent are: SiO22 ≥95％，Fe2 O3 ≤3％，Al2 O3 ≤2％。
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| CN202297628U (en) * | 2011-10-08 | 2012-07-04 | 山西潞安环保能源开发股份有限公司 | Industrial simulation experiment device for conveying performance of pulverized coal injected by blast furnace |
| CN202430239U (en) * | 2011-12-09 | 2012-09-12 | 首钢总公司 | Experimental device for stimulating burning of pulverized coal sprayed and blown by blast furnace |
| CN204039427U (en) * | 2014-05-15 | 2014-12-24 | 首钢总公司 | A kind of device measuring blast furnace injection rate of pulverized coal combustion |
| CN205954040U (en) * | 2016-06-28 | 2017-02-15 | 青岛恒拓环保科技有限公司 | Intelligence coal injection system |
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