The oven drying process of the converter

Abstract

The present invention discloses a baking process for a converter, comprising: adding coke with a first preset weight to the converter; adding firewood with a second preset weight into the scrap steel bucket, igniting it and then adding it into the converter; adding coke to the converter in batches according to the baking duration; adjusting the oxygen lance flow rate according to the baking duration; and adjusting the oxygen lance position according to the baking duration. By means of the present invention, the baking quality of the converter is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of steelmaking, and in particular relates to a converter baking process. Background Art

[0002] After the converter is built, it must be baked before it is commissioned. This process removes moisture from the furnace and allows the lining bricks to expand as needed to meet steelmaking requirements. Modern steel companies are increasingly pursuing a longer converter lifespan. Poor converter baking not only increases costs, significantly impacts production organization, and reduces the lifespan of the converter. Therefore, improving converter baking quality is a pressing technical issue. Summary of the Invention

[0003] The embodiment of the present invention provides a converter baking process, which improves the converter baking quality.

[0004] In a first aspect, an embodiment of the present invention provides a converter baking process, comprising: adding a first preset weight of coke to the converter; adding a second preset weight of firewood into a scrap steel bucket, igniting it and adding it into the converter; adding coke into the converter in batches according to the baking time; adjusting the oxygen lance flow rate according to the baking time; and adjusting the oxygen lance position according to the baking time.

[0005] In combination with the first aspect of the present invention, in some embodiments, the adding of coke into the converter in batches according to the baking time includes: within the first time range, controlling the amount of coke added to 300 kg per 15 minutes; within the second time range, controlling the amount of coke added to 200 kg per 15 minutes; within the third time range, controlling the amount of coke added to 300 kg per 15 minutes.

[0006] In combination with the first aspect of the present invention, in some embodiments, adjusting the oxygen lance flow rate according to the oven duration includes: controlling the oxygen flow rate to 12000 NM within the fourth duration range. 3 / h~15000NM 3 / h; in the fifth time range, the oxygen flow rate is controlled to 13000NM 3 / h~14000NM 3 / h; in the sixth time range, control the oxygen flow rate to 15000NM 3 / h.

[0007] In combination with the first aspect of the present invention, in some embodiments, adjusting the oxygen lance position according to the furnace baking time includes: within the seventh time range, controlling the distance between the oxygen lance position and the furnace bottom bricks to be 2.0m~3.0m; within the eighth time range, controlling the distance between the oxygen lance position and the furnace bottom bricks to be 1.0m~1.5m.

[0008] In combination with the first aspect of the present invention, in some embodiments, it further includes: after the baking furnace duration is greater than the first duration threshold, empty the remaining slag and charge iron for steelmaking.

[0009] In combination with the first aspect of the present invention, in some embodiments, before adding the first preset weight of coke to the converter, it further includes: before baking the converter, control all the bottom blowing pipeline manual valves of the converter to be opened and the vent valve to be closed.

[0010] In combination with the first aspect of the present invention, in some embodiments, it includes: the first preset weight includes 2 tons; the second preset weight includes 2 tons.

[0011] In combination with the first aspect of the present invention, in some embodiments, the converter includes a dry method evaporation cooler, and the method further includes: if the inlet temperature of the dry method evaporation cooler is lower than the first temperature threshold, add supplementary coke.

[0012] In combination with the first aspect of the present invention, in some embodiments, the first duration range includes the 61st minute to the 120th minute of baking the furnace; the second duration range includes the 121st minute to the 180th minute of baking the furnace; the third duration range includes the 181st minute to the 240th minute of baking the furnace.

[0013] One or more technical solutions provided by the embodiments of the present invention at least achieve the following technical effects or advantages:

[0014] In the embodiments of the present invention, by adding the first preset weight of coke to the converter; adding the second preset weight of firewood into the scrap steel bucket, igniting it and then adding it into the converter; adding coke to the converter in batches according to the baking furnace duration; adjusting the oxygen lance flow rate according to the baking furnace duration; adjusting the oxygen lance position according to the baking furnace duration. By adjusting the coke addition amount, the oxygen lance flow rate and the oxygen lance position, the baking furnace process is controlled, so that the coke does not agglomerate, the melting rate of the coke is reasonably controlled, the converter heats up stably, the lining bricks are heated evenly, the moisture of the lining bricks does not evaporate too fast in the early stage of baking the furnace, effectively avoiding cracks in the lining bricks, and at the same time controlling the consumption of coke, reducing environmental pollution and improving the service life of the lining bricks. Therefore, the baking furnace quality of the converter is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1This is the flowchart of the converter baking process in the embodiments of the present invention. Detailed implementation manners

[0017] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0018] In the present invention, descriptions such as "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0019] The embodiments of the present invention provide a converter baking process, and the converter baking process is designed for large converters. Refer to Figure 1 As shown, the method includes the following steps S101 to S105:

[0020] S101: Add coke with a first preset weight to the converter.

[0021] It can be understood that before adding coke with a first preset weight to the converter, it further includes: before baking the converter, control all the manual valves of the bottom blowing pipelines of the converter to be opened, and the blow-off valve to be closed. Therefore, the air permeability of the bottom blowing pipelines can be ensured.

[0022] It can be understood that the first preset weight includes 2 tons, or it can also be 2.1 tons, 2.2 tons, and 1.9 tons. The first preset weight is designed for large converters.

[0023] S102: Add firewood with a second preset weight to the scrap steel bucket, light it, and then add it to the converter.

[0024] It can be understood that the second preset weight includes 2 tons, or it can also be 2.1 tons, 2.2 tons, and 1.9 tons. The second preset weight is designed for large converters.

[0025] S103: Add coke to the converter in batches according to the baking duration.

[0026] It is understandable that the method of adding coke to the converter in batches according to the baking duration includes the following steps S1031 to S1033:

[0027] S1031: Within the first duration range, control the coke addition amount to be 300 kg every 15 minutes.

[0028] It should be noted that the first duration range can be the 61st minute to the 120th minute of the baking process.

[0029] S1032: Within the second duration range, control the coke addition amount to be 200 kg every 15 minutes.

[0030] It should be noted that the second duration range can be the 121st minute to the 180th minute of the baking process.

[0031] S1033: Within the third duration range, control the coke addition amount to be 300 kg every 15 minutes.

[0032] It should be noted that the third duration range can be the 181st minute to the 240th minute of the baking process.

[0033] It should be noted that after each addition of coke, the lance is moved up and down twice, and the amplitude can be 50 cm, which can achieve the full combustion of coke.

[0034] It should be noted that since the main gas generated during the baking process by the combustion of coke is CO2, no additional coke is added in the first 60 minutes, which can enable the full combustion of coke. Step S103 achieves that the coke does not agglomerate, reasonably controls the melting rate of coke, achieves the effect of stable temperature rise, and at the same time controls the consumption of coke, reducing environmental pollution.

[0035] S104: Adjust the oxygen lance flow rate according to the baking duration.

[0036] It is understandable that the method of adjusting the oxygen lance flow rate according to the baking duration includes the following steps S1041 to S1043:

[0037] S1041: Within the fourth duration range, control the oxygen flow rate to be 12000 NM 3 / h to 15000 NM 3 / h;

[0038] It should be noted that the fourth duration range can be the 0th minute to the 60th minute of the baking process.

[0039] S1042: Within the fifth duration range, control the oxygen flow rate to be 13000 NM 3 / h to 14000 NM 3 / h;

[0040] It should be noted that the fifth time range can be from the 61st minute to the 180th minute of the furnace baking.

[0041] S1043: Within the sixth time range, control the oxygen flow rate to be 15000 NM 3 / h.

[0042] It should be noted that the sixth time range can be from the 181st minute to the 240th minute of the furnace baking.

[0043] It should be noted that in the first 60 minutes of the furnace baking, control the oxygen flow rate to be 12000 NM 3 / h to 15000 NM 3 / h, which can achieve controlling the converter to heat up at a rate of 2 °C / min, avoid too fast heating speed, reduce the too fast removal of moisture in the furnace lining, and avoid the formation of cracks. Step S104 achieves the effect of controlling the stable heating of the converter, the furnace lining bricks are evenly heated, the moisture of the furnace lining bricks does not evaporate too fast in the early stage of furnace baking, effectively avoiding cracks in the furnace lining converter and improving the service life of the furnace lining converter.

[0044] S105: Adjust the lance position according to the furnace baking duration.

[0045] It can be understood that the method of adjusting the lance position according to the furnace baking duration includes the following steps S1051 to S1052:

[0046] S1051: Within the seventh time range, control the distance between the lance position and the bottom brick of the furnace to be 2.0 m to 3.0 m;

[0047] It should be noted that the seventh time range can be from the 0th minute to the 60th minute of the furnace baking.

[0048] S1052: Within the eighth time range, control the distance between the lance position and the bottom brick of the furnace to be 1.0 m to 1.5 m.

[0049] It should be noted that the eighth time range can be from the 61st minute to the 240th minute of the furnace baking.

[0050] It should be noted that controlling the distance between the lance position and the bottom brick of the furnace to be 1.0 m to 1.5 m within the eighth time range of the furnace baking can keep the converter in a heat preservation state, the furnace lining bricks undergo a phase change, and reduce the risk of spalling. Step S105 achieves the effect of controlling the stable heating of the converter, the furnace lining bricks are evenly heated, the moisture of the furnace lining bricks does not evaporate too fast in the early stage of furnace baking, effectively avoiding cracks in the furnace lining converter and improving the service life of the furnace lining converter.

[0051] It can be understood that the converter includes a dry evaporative cooler, and the furnace baking process of the converter further includes: during the furnace baking process, if the inlet temperature of the dry evaporative cooler is lower than the first temperature threshold, add coke.

[0052] It should be noted that the first temperature threshold can be 120 °C.

[0053] It can be understood that after the oven drying is completed, the oven drying process of the converter further includes: after the oven drying duration is greater than the first duration threshold, pouring out the remaining slag completely and charging iron for steelmaking.

[0054] It should be noted that the first duration threshold can be 240 minutes.

[0055] To enhance the understanding of the embodiments of the present invention, taking a 100-ton to 300-ton converter as an example, the oven drying process of the converter is illustrated as follows:

[0056] Step 1: Before the oven drying of the converter, control all the manual valves of the bottom blowing pipelines of the converter to be opened and the vent valve to be closed.

[0057] Step 2: Prepare 2 tons of coke in the high-level bunker of the converter 15 minutes in advance and add it into the converter through the charging pipe.

[0058] Step 3: Add 2 tons of firewood into the scrap steel bucket, ignite it 10 minutes in advance and then add it into the converter.

[0059] Step 4: Within 61 minutes to 120 minutes, control the coke addition amount to be 300 kg every 15 minutes; within 121 minutes to 180 minutes, control the coke addition amount to be 200 kg every 15 minutes; within 181 minutes to 240 minutes, control the coke addition amount to be 300 kg every 15 minutes. After each addition of coke, move the lance up and down twice, and the amplitude can be 50 cm.

[0060] Step 5: Within 0 minutes to 60 minutes, control the oxygen flow rate to be 13000 NM 3 / h; within 61 minutes to 180 minutes, control the oxygen flow rate to be 14000 NM 3 / h; within 181 minutes to 240 minutes, control the oxygen flow rate to be 15000 NM 3 / h.

[0061] Step 6: Within 0 minutes to 60 minutes, control the distance between the lance tip and the bottom brick of the furnace to be 2.0 m to 3.0 m; within 61 minutes to 240 minutes, control the distance between the lance tip and the bottom brick of the furnace to be 1.0 m to 1.5 m.

[0062] Step 7: If the inlet temperature of the dry type evaporation cooler is lower than 120 °C, add supplementary coke.

[0063] Step 8: After the oven drying duration is greater than 240 minutes, pour out the remaining slag completely and charge iron for steelmaking.

[0064] It should be noted that by adopting the oven drying process of the embodiment of the present invention, the oven drying duration can be reduced to a certain extent.

[0065] In the embodiment of the present invention, first preset weight of coke is added to the converter; second preset weight of firewood is added into the scrap steel bucket, and after being ignited, it is added into the converter; according to the oven drying duration, coke is added to the converter in batches; according to the oven drying duration, the oxygen lance flow rate is adjusted; according to the oven drying duration, the oxygen lance position is adjusted. By adjusting the coke addition amount, the oxygen lance flow rate and the oxygen lance position, the oven drying process is controlled, so that the coke does not agglomerate, the melting rate of the coke is reasonably controlled, the converter is heated up stably, the lining bricks are heated evenly, the moisture of the lining bricks does not evaporate too fast in the early stage of oven drying, the cracks of the lining bricks are effectively avoided, at the same time, the consumption of coke is controlled, the environmental pollution is reduced, and the service life of the lining bricks is improved. Therefore, the oven drying quality of the converter is improved.

[0066] The above are only the embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. A baking process for a converter, characterized in that, Including: Adding coke with a first preset weight to the converter; Adding firewood with a second preset weight into the scrap steel bucket, igniting it and then adding it into the converter; Adding coke to the converter in batches according to the baking time, including: within the first time range, controlling the coke addition amount to be 300 kg every 15 minutes; within the second time range, controlling the coke addition amount to be 200 kg every 15 minutes; within the third time range, controlling the coke addition amount to be 300 kg every 15 minutes; wherein, the first time range includes the 61st minute to the 120th minute of the baking process; the second time range includes the 121st minute to the 180th minute of the baking process; the third time range includes the 181st minute to the 240th minute of the baking process; Adjusting the oxygen lance flow rate according to the baking time; Adjusting the oxygen lance position according to the baking time.

2. The oven drying process of the converter according to claim 1, characterized in that, The adjusting the oxygen lance flow rate according to the baking time includes: Within the fourth time period, control the oxygen flow rate to be 12000 NM 3 / h to 15000 NM 3 / h; Within the fifth time range, control the oxygen flow rate to be 13000 NM 3 / h to 14000 NM 3 / h; Within the sixth time range, control the oxygen flow rate to be 15000 NM 3 / h.

3. The oven drying process of the converter according to claim 1, characterized in that, The adjusting the oxygen lance position according to the baking time includes: Within the seventh time range, controlling the distance between the oxygen lance position and the bottom brick of the furnace to be 2.0 m to 3.0 m; Within the eighth time range, controlling the distance between the oxygen lance position and the bottom brick of the furnace to be 1.0 m to 1.5 m.

4. The oven drying process of the converter according to claim 1, characterized in that, Also including: After the baking time is greater than the first time threshold, pouring out the remaining slag and charging iron for steelmaking.

5. The oven drying process of the converter according to claim 1, characterized in that, ​ ​ 6. The oven drying process of the converter according to claim 1, characterized in that, ​ ​ 7. The oven drying process of the converter according to claim 1, characterized in that, ​ ​ 8. The oven drying process of the converter according to claim 1, characterized in that, ​ ​

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