Efficient converter baking method

Abstract

According to the method, in the initial stage, the high gun position, the large flame coverage range, the uniform heat distribution and the slow temperature rise suitable for the whole furnace lining are adopted, the risk of thermal stress cracks is reduced, the moisture of the furnace lining is removed, and bursting caused by steam pressure is prevented; in the middle stage, the gun position is gradually lowered, the temperature is increased, sintering of the refractory material is promoted, and a compact layer is formed; finally, in the later stage, the temperature is rapidly increased, low-gun-position baking is adopted, the flame impact force is high, heat is concentrated, the total oven baking time can be controlled within 35 min under the condition that the oven baking effect is guaranteed, and the oven baking efficiency is remarkably improved; the purpose of adopting different gun positions to bake the furnace is to optimize the furnace bake effect, ensure that the furnace lining is uniformly heated and safely sintered, and prolong the service life of the furnace body.

Description

Technical Field

[0001] The present invention relates to the field of machinery, in particular to the technical field of mechanical components, and specifically to a high-efficiency converter drying method. Background Art

[0002] The converter lining consists of a permanent layer, a filling material, and a working layer. Currently, the main material used for the converter working layer is magnesia-carbon bricks. Before the new converter lining is put into use, it needs to be baked. The traditional baking process takes a long time, which not only affects production efficiency but also wastes energy. Chinese Patent Application No. 202310815935.4 discloses a converter baking process that requires a baking time of 240 minutes; Chinese Patent Application No. 201710576527.2 discloses a baking method for a 120t converter after replacing the refractory material of the lining, with a baking time of about 3 hours. Summary of the Invention

[0003] In view of the deficiencies in the prior art, the present invention provides a converter high-efficiency furnace drying method, which shortens the furnace drying time.

[0004] The present invention is a high-efficiency converter drying method implemented by the following technical solution, comprising the following steps: a. Initial stage: Using a high gun position, the flame covers a large area and the heat is evenly distributed, which is suitable for the slow heating of the entire furnace lining and reduces the risk of thermal stress cracks. Its purpose is to drive away moisture from the furnace lining and prevent bursting caused by steam pressure; b. Mid-term stage: gradually lower the gun position, increase the temperature, promote the sintering of refractory materials, and form a dense layer; c. Late stage: In order to quickly heat up, low gun position baking is adopted, the flame impact is strong and the heat is concentrated.

[0005] Preferably, an ignition operation is performed before the initial stage. In 0-3 minutes, the gun position is controlled between 1650-1700 mm and the oxygen pressure is controlled between 0.20-0.23 MPa, so as to quickly ignite the coke in the furnace. A lower oxygen pressure will not play the role of oxygen in assisting combustion, while a higher oxygen pressure will be detrimental to igniting the unignited coke.

[0006] As a preference, before ignition, 7-10 tons of coke should be prepared in front of the furnace and ignited in the scrap steel hopper, and the ignited coke should be added to the furnace, and 3-5 tons of coke should be prepared in the high-level silo.

[0007] Preferably, the initial stage includes adjusting the oxygen pressure to between 0.29-0.35 MPa after the ignition operation, that is, 3 minutes later, and the gun position remains unchanged.

[0008] As preferred, the lance position is lowered to 1580-1630mm in the middle stage, i.e. 5.13-15min, and the oxygen pressure is controlled between 0.29-0.35Mpa.

[0009] As preferred, the lance position is lowered to 1400-1450mm in the later stage, i.e. 25-27min, and the oxygen pressure is controlled between 0.29-0.35Mpa.

[0010] As preferred, 300-500kg of coke is added from the high-position stock bin every 3-5min between 12-30min.

[0011] The method has the following advantages: in the initial stage, the high lance position is adopted, the flame covers a large range, the heat is uniformly distributed, the whole lining is slowly heated, the risk of thermal stress cracking is reduced, the moisture in the lining is removed, and the steam pressure is prevented from causing explosion; then in the middle stage, the lance position is gradually lowered, the temperature is increased, the refractory material is promoted to sinter, and a dense layer is formed; finally in the later stage, the temperature is rapidly increased, the low lance position is adopted for roasting, the flame impact is strong, the heat is concentrated, and the total roasting time can be controlled within 35min under the condition of ensuring the roasting effect, so that the roasting efficiency is significantly improved; the purpose of adopting different lance positions for roasting is to optimize the roasting effect, ensure that the lining is uniformly heated and safely sintered, and prolong the service life of the furnace body. DETAILED DESCRIPTION

[0012] To clearly illustrate the technical features of the present scheme, the present scheme will be described below through specific embodiments.

[0013] The present application discloses a kind of high-efficiency roasting method of converter.

[0014] The method comprises the following steps: a, 8t of coke is ignited in the scrap steel bin before roasting; 4t of coke is prepared in the high-position stock bin.

[0015] b, the ignited coke is added to the furnace; c, ignition operation: oxygen supply for 0-3min, lance position is 1670mm, oxygen pressure is 0.22Mpa; d, after oxygen supply for 3min, the oxygen pressure is adjusted to 0.33Mpa, and the lance position remains unchanged; high lance position is adopted, the flame covers a large range, the heat is uniformly distributed, the whole lining is slowly heated, and the risk of thermal stress cracking is reduced, which aims to remove the moisture in the lining and prevent the steam pressure from causing explosion; e, when oxygen supply is 13.5min, the lance position is lowered to 1600mm, and the oxygen pressure is controlled at 0.33Mpa; the lance position is gradually lowered, the temperature is increased, the refractory material is promoted to sinter, and a dense layer is formed; f. When the oxygen supply is 26 minutes, the gun position is lowered to 1430mm, and the oxygen gun is controlled at 0.33Mpa; in order to quickly heat up, low gun position baking is adopted, the flame impact is strong, and the heat is concentrated.

[0016] g. When the oxygen supply reaches 33.5min, turn off the oxygen and lift the gun.

[0017] At oxygen supply times of 12 minutes, 16 minutes, 19 minutes, 23 minutes, 27 minutes and 31 minutes, 350 kg, 533 kg, 450 kg, 566 kg, 380 kg and 456 kg of coke were added into the furnace from the high-level silo respectively.

[0018] This solution consumes a total of 6268Nm of oxygen 3 , the baking effect is good.

[0019] This solution uses "high-low-low" gun position control to optimize the furnace drying effect, ensure uniform heating of the furnace lining, safe sintering, and extend the life of the furnace body.

[0020] Of course, the above description is not limited to the above examples. The technical features not described in the present invention can be achieved by or by adopting existing technologies, which will not be described here. The above embodiments are only used to illustrate the technical solutions of the present invention and are not limitations of the present invention. The present invention is described in detail with reference to the preferred implementation methods. Ordinary technicians in this field should understand that changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention do not depart from the purpose of the present invention and should also fall within the scope of protection of the claims of the present invention.

Claims

1. A converter high-efficiency drying method, characterized in that: The following steps are involved: a. Initial stage: Using a high gun position, the flame covers a large area and the heat is evenly distributed, which is suitable for the slow heating of the entire furnace lining and reduces the risk of thermal stress cracks. Its purpose is to drive away moisture from the furnace lining and prevent bursting caused by steam pressure; b. Mid-term stage: gradually lower the gun position, increase the temperature, promote the sintering of refractory materials, and form a dense layer; c. Late stage: In order to quickly heat up, low gun position baking is adopted, the flame impact is strong and the heat is concentrated.

2. The converter high-efficiency drying method according to claim 1, characterized in that: Before the initial stage, ignition operation must be carried out. In 0-3 minutes, the gun position is controlled between 1650-1700mm, and the oxygen pressure is controlled between 0.20-0.23Mpa, so as to quickly ignite the coke in the furnace. If the oxygen pressure is too low, it will not play the role of oxygen combustion assistance, and if it is too high, it will be unfavorable to ignite the unignited coke.

3. The converter high-efficiency drying method according to claim 2, characterized in that: Before ignition, 7-10t of coke must be prepared in front of the furnace and ignited in the scrap steel bucket, and the ignited coke must be added to the furnace, and 3-5t of coke must be prepared in the high-level silo.

4. The converter high-efficiency drying method according to claim 2, characterized in that: The initial stage includes adjusting the oxygen pressure to between 0.29-0.35 MPa 3 minutes after the ignition operation, and the gun position remains unchanged.

5. The converter high-efficiency drying method according to claim 4, characterized in that: In the middle stage, that is, from 5.13 to 15 minutes, the gun position is lowered to between 1580-1630mm, and the oxygen pressure is controlled between 0.29-0.35Mpa.

6. The converter high-efficiency drying method according to claim 5, characterized in that: In the later stage, that is, at 25-27 minutes, the gun position is lowered to between 1400-1450mm, and the oxygen pressure is controlled between 0.29-0.35Mpa.

7. The converter high-efficiency drying method according to claim 2, characterized in that: During the 12-30 minutes of baking, 300-500 kg of coke is added from the high-level silo every 3-5 minutes.