Converter digestion dust removal ball explosion prevention smelting method

Abstract

The present application provides a converter digestion dedusting ash ball explosion prevention smelting method, the method comprises the following steps in sequence: high furnace molten iron into desulfurization station for desulfurization and slagging operation; using top and bottom combined blowing converter smelting; blowing adopts low-high-low oxygen supply operation mode. Under the premise of using dry dedusting system in converter process, the converter blowing process digests dedusting ash ball, realizes the recycling of solid waste, effectively controls the frequency of explosion to 0-1 times / month, not only reduces the cost of steelmaking process, but also reduces the pollution to the environment, the production operation process is simple, and the matching degree with the commonly used electric dedusting process is high.

Description

Technical Field

[0001] This invention relates to the field of converter smelting technology, and in particular to a method for preventing explosions during converter smelting by digesting and removing dust ash balls. Background Technology

[0002] Modern steel plants closely follow national environmental protection requirements, and most adopt dry dust removal systems. While these systems effectively control the dust content in flue gas and meet national environmental standards, over time, the amount of iron oxides produced by the dust removal systems increases, becoming a type of iron-containing solid waste. Directly selling this waste not only wastes iron resources but may also pollute the environment. Therefore, researching how to treat this iron-containing solid waste has become a research direction for many steel companies.

[0003] The iron oxides produced are outsourced to be processed into dust collector ash balls, which are then recycled as a coolant during the converter smelting process, replacing the coolants currently used in the production process, such as sinter. However, the dust collector ash balls contain carbon, which often causes explosions when added during the blowing process, affecting the normal smelting rhythm and equipment stability. Therefore, the problem of preventing explosions by digesting the dust collector ash balls in the converter is particularly important and challenging. Summary of the Invention

[0004] This invention proposes a method for preventing explosions in converter smelting by digesting dust removal ash balls, aiming to solve the problem of frequent explosions of digested dust removal ash balls in the existing steel plant converter smelting process.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a method for preventing explosions in converter smelting by digesting and removing dust ash balls, the method comprising the following steps in sequence:

[0006] S1. Blast furnace molten iron enters the desulfurization station for desulfurization and slag removal operations;

[0007] S2. Smelting using a top-and-bottom blown converter;

[0008] S3. The blowing process adopts a low-high-low oxygen supply operation mode;

[0009] S3.1 After normal ignition, when the oxygen supply process reaches 2%, the ignition gun is raised to the normal blowing gun position, and the ignition oxygen supply is 15000 Nm. 3 / h, immediately and gradually increasing the oxygen supply to 30000-32000 Nm³. 3 / h, after the flame is normal, add the first batch of slag-forming material. The slag-forming material includes dust removal ash balls and other calcium-based auxiliary materials. The amount added is 1 / 3 to 1 / 2 of the total amount added. After the first batch of slag-forming material is added, slag-forming material is continuously added. If the flame is abnormal, stop adding in time and add it again in time when the flame is normal. The principle of adding material is multiple batches in small quantities. The amount of other calcium-based auxiliary materials added in each batch is 300-500 kg. 10 minutes before smelting, prepare enough lime according to the alkalinity requirements. 12 minutes before smelting, prepare enough dust removal ash balls or sinter according to the requirements based on the temperature of the molten steel.

[0010] S3.2 When the carbon-oxygen reaction begins, add the second batch of slag-forming material, and add it in multiple batches and small quantities according to the slag formation. During the smelting process, adjust the gun position and feeding timing according to the slag formation effect of the dust removal ash balls. The amount of dust removal ash balls added in each batch of slag-forming material is ≤500Kg, and the amount of other calcium auxiliary materials added in each batch is ≤500Kg.

[0011] S3.3 When the blowing process reaches 85-90% of the oxygen supply stage, use the auxiliary lance TSC probe to determine carbon content, measure temperature, and take samples. Then, add some slag-forming material for adjustment based on the determined carbon content and measured temperature. Monitor the smelting process based on the auxiliary lance test results until the smelting process requirements are met before lance removal. At the end of the blowing process, use the auxiliary lance TSO probe to determine carbon content, measure temperature, take samples, and determine oxygen levels. Before lance removal at the final stage, lower the deep blowing lance position to 900mm and increase the oxygen supply to 32000 Nm³. 3 / h, to perform deep decarburization and homogenize the composition and temperature of molten steel.

[0012] Preferably, the parameters for the desulfurization operation in step 1 are controlled as follows: inlet temperature ≥1350℃, desulfurizing agent dosage 4-6kg / t, rotation speed during feeding 60-70rpm, rotation speed after feeding 80-100rpm, and stirring time controlled at 15-20min.

[0013] Preferably, the raw material composition and weight percentage of the main metal material input in the smelting process described in step 2 are as follows: 80-85% molten iron, with the remainder being scrap steel, and the molten iron containing 0.20-0.55% Si, 0.25-0.45% Mn, and ≤0.5% slag.

[0014] Preferably, in step 3.1, the oxygen supply intensity during the blowing process is controlled to be 3.5-4.5 Nm. 3 The bottom-blown argon flow rate is controlled at 0.05-0.10 Nm³ / min·t. 3 / min·t, the ignition gun position is set at 1500mm, and the normal blowing gun position is 1400-1800mm. The slag-forming material is added using symmetrical silos, and the dust removal ash balls are added using continuous feeding silos to ensure that the dust removal ash balls are added stably and to reduce the carbon-oxygen reaction caused by the dust removal ash balls.

[0015] Preferably, the composition and proportion of the dust removal ash balls in step 3.2 are: TFe≥50%, CaO≥7%, SiO2≤5%, P≤0.20%, S≤0.20%, H2O≤5%, surface strength≥800N / ball, and dust removal ash ball particle size range of 10~50mm greater than 90%.

[0016] Preferably, the dust removal ash balls in step 3 melt relatively slowly. To prevent them from not melting and reducing completely, the dust removal ash balls should not be added 3 minutes before the end of smelting.

[0017] Preferably, the dust collector ash balls mentioned in step 3 have a certain carbon content. Adding too much during re-blowing will cause a sharp increase in the CO concentration in the flue gas, which will bring the risk of explosion. Therefore, the amount of dust collector ash balls added during re-blowing should be controlled to ≤1000kg. The excess can be replaced with lime or limestone. If the adjustment range is large and more than 1000kg of dust collector ash balls need to be added, nitrogen curtain operation must be carried out.

[0018] Preferably, the weight percentages of each component of the desulfurizing agent in step 1 are: CaO≥80.0%, SiO2≤5.0%, CaF2≥7.0%, S≤0.040%, and the particle size of the desulfurizing agent is 0.2-1.5mm.

[0019] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0020] With the use of a dry dust removal system in the converter process, the converter blowing process digests the dust ash balls, realizes the recycling and reuse of solid waste, and effectively controls the explosion relief frequency to 0-1 times / month. This not only reduces the cost of the steelmaking process, but also reduces environmental pollution. The production operation process is simple and has a high degree of compatibility with the currently widely used electrostatic precipitator technology. Detailed Implementation

[0021] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described below through embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0022] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways than those described herein, and therefore the invention is not limited to the specific embodiments disclosed in the following specification.

[0023] Converter flue gas contains a large amount of iron oxides. After passing through the dry dust removal system, it will successively generate primary coarse ash and primary fine ash, plus iron oxide scale generated from billet extrusion or finishing, which together constitute the raw materials for solid waste recycling in steelmaking plants. The carbon and total iron content in the three types of iron-containing solid wastes vary greatly. Based on the monthly production of converter dust and iron oxide scale and the requirements of steelmaking process, the following ratio is designed: dust ash 30-60%, iron oxide scale 20-50%, binder 3-6%. Through high-efficiency composite binder and corresponding process technology, the iron oxides are mixed according to the ratio and then pressed into dust ash balls. The composition is TFe≥50%, CaO≥7%, SiO2≤5%, P≤0.20%, S≤0.20%, H2O≤5%, surface strength≥800N / ball, and dust ash ball particle size range 10-50mm greater than 90%.

[0024] Electrostatic precipitator (ESP) explosion venting occurs during the converter steelmaking process when molten iron reacts violently with blown-in oxygen, generating a large amount of high-temperature flue gas. Although the furnace mouth employs a slightly positive pressure design, some air inevitably mixes in. The main components of the flue gas are CO, CO2, O2, N2, and dust. The flammable gas in the flue gas is primarily CO. The conditions for an explosion are: ① The ratio of flammable gas to oxygen reaches the explosion limit, i.e., ω(CO) ≥ 9%, ω(O2) ≥ 6%; or ω(H2) ≥ 3%, ω(O2) ≥ 4%; ② There is an open flame, i.e., an electric spark is generated during discharge between the electrodes; ③ It is within a confined space, i.e., the ESP is a confined space. During the operation of the ESP, the generation of ignition sparks from electric field discharge is unavoidable. Therefore, if the mixed gas exceeds the limit, an explosion will occur within the ESP, causing the explosion venting valve to open.

[0025] Example 1

[0026] This embodiment provides a method for preventing explosions in converter digestion and dust removal ash balls during smelting, which can solve the problem of frequent explosions of digestion and dust removal ash balls in existing steel plant converter smelting processes.

[0027] The smelting method includes the following steps in sequence:

[0028] S1. Blast furnace molten iron enters the desulfurization station for desulfurization and slag removal operations. Specifically, the inlet temperature is 1350℃, the desulfurizing agent dosage is 4kg / t, the speed during feeding is 60rpm, the speed after feeding is 80rpm, the stirring time is controlled at 15min, and the molten iron after desulfurization is subjected to slag removal treatment.

[0029] S2. The top and bottom blowing converter is used for smelting. The weight percentage of the raw materials for the main metal material is: 80% iron, the balance is scrap steel, the iron contains 0.20% Si and 0.25% Mn, the temperature at the desulfurization station is 1350℃, and the slag content is 0.5%.

[0030] S3. The blowing process adopts a low-high-low oxygen supply operation mode, with the oxygen supply intensity controlled at 3.5 Nm. 3 / (min·t), the bottom-blown argon flow rate is controlled at 0.05 Nm³. 3 / (min·t), the ignition gun position is set to 1500mm. After normal ignition, when the oxygen supply process reaches 2%, the ignition gun is raised to the normal blowing gun position of 1600mm, and the ignition flow rate is 15000Nm. 3 / h, automatically increasing the oxygen supply to 30000 Nm³ after 45 seconds in a stepped manner. 3 / h, add the first batch of slag-forming materials (including dust removal ash balls and other calcium-based auxiliary materials) 1 minute after the blowing starts. The amount added is 1 / 3 of the total amount added. Use symmetrical silos for addition. The dust removal ash balls are mainly added through continuous feeding silos to ensure a stable addition of the dust removal ash balls and reduce the carbon-oxygen reaction caused by the dust removal ash balls. After the first batch of slag-forming materials is added, slag-forming materials are continuously added. If the flame is abnormal, stop adding in time and add in time after the flame is normal. The principle of adding materials is multiple batches in small quantities. The amount of other calcium-based auxiliary materials added in each batch is 300 kg. 10 minutes before smelting, prepare enough lime according to the basicity requirements. 12 minutes before smelting, prepare enough dust removal ash balls or sinter according to the requirements based on the temperature of the molten steel.

[0031] S4. When the carbon-oxygen reaction begins, add the second batch of slag-forming material, following the principle of adding in multiple batches and small quantities according to the slag formation. The amount of dust removal ash balls added per batch is 450 kg; the amount of other slag-forming materials added per batch is also 450 kg. The iron content and cooling effect of the dust removal balls are similar to those of blast furnace return ore, but the slag formation effect is relatively slow. During the smelting process, adjust the lance position and the timing of adding materials according to the actual usage effect. The dust removal ash balls melt relatively slowly. To prevent them from not being fully melted and reduced, the dust removal ash balls should not be added 3 minutes before the end of smelting.

[0032] S5. When the blowing process reaches 85-90% of the oxygen supply stage, use the auxiliary lance TSC probe for carbon determination, temperature measurement, and sampling. Then, add some slag-forming material for adjustment based on the determined carbon and measured temperature. Monitor the smelting process based on the auxiliary lance test results until the smelting process requirements are met before lance removal. At the end of the blowing process, use the auxiliary lance TSO probe for carbon determination, temperature measurement, sampling, and oxygen determination. Before final lance removal, lower the deep blowing lance position to 900mm and increase the oxygen supply to 32000 Nm³. 3 / h, to perform deep decarburization and homogenize the composition and temperature of molten steel;

[0033] S6. Dust collector ash balls have a certain carbon content. Adding too many during re-blowing will cause a sharp increase in the CO concentration in the flue gas, which will bring the risk of explosion. Therefore, the amount of ash balls added during re-blowing should be controlled to ≤1000kg. The excess can be replaced with lime or limestone. If the adjustment range is large and more than 1000kg of dust collector ash balls need to be added, nitrogen curtain operation must be carried out.

[0034] The composition and proportion of the dust removal ash balls in this embodiment are as follows: TFe 80%, CaO 9.6%, SiO 25%, P 0.20%, S 0.20%, H2O 5%, with a surface strength of 800N / piece, and the dust removal ash ball particle size range of 10-50mm accounting for 90%.

[0035] The weight percentages of each component of the desulfurizer in this embodiment are: CaO 80.0%, SiO2 5.0%, CaF1 4.96%, S 0.040%, and the particle size of the desulfurizer is 0.5-1.0 mm.

[0036] Example 2

[0037] The smelting method includes the following steps in sequence:

[0038] S1. Blast furnace molten iron enters the desulfurization station for desulfurization and slag removal operations. Specifically, the inlet temperature is 1380℃, the desulfurizing agent dosage is 4kg / t, the speed during feeding is 65rpm, the speed after feeding is 90rpm, the stirring time is controlled at 18min, and the molten iron after desulfurization is subjected to slag removal treatment.

[0039] S2. The top and bottom blowing converter is used for smelting. The weight percentage of the raw materials for the main metal material is: 83% iron, the balance is scrap steel, the iron contains 0.35% Si and 0.35% Mn, the temperature at the desulfurization station is 1400℃, and the slag content is 0.4%.

[0040] S3. The blowing process adopts a low-high-low oxygen supply operation mode, with the oxygen supply intensity controlled at 4 Nm. 3 / (min·t), the bottom-blown argon flow rate is controlled at 0.08 Nm 3 / (min·t), the ignition gun position is set to 1500mm. After normal ignition, when the oxygen supply process reaches 2%, the position is raised to the normal blowing gun position of 1700mm, and the ignition flow rate is 15000Nm. 3 / h, after 45 seconds the oxygen supply will automatically increase in stages to 31000 Nm³. 3 / h, one minute after the blowing starts, add the first batch of slag-forming materials (including dust removal ash balls and other calcium-based auxiliary materials), the amount added is 45% of the total amount added, and symmetrical silos are used for addition; among them, the dust removal ash balls are mainly added through continuous feeding silos, so that the dust removal ash balls are added smoothly and the carbon-oxygen reaction brought by the dust removal ash balls is reduced.

[0041] S4. When the carbon-oxygen reaction begins, add the second batch of slag-forming material. Depending on the slag formation, follow the principle of adding in multiple batches and small quantities. The amount of dust removal ash balls added per batch is 450 kg. The amount of other slag-forming materials added per batch is also 450 kg. The iron content and cooling effect of the dust removal balls are similar to those of blast furnace return ore, but the slag formation effect is relatively slow. Adjust the lance position and the timing of adding materials during the smelting process according to the actual usage effect. The dust removal ash balls melt relatively slowly. To prevent them from not melting and reducing completely, do not add dust removal ash balls 3 minutes before the end of smelting.

[0042] S5. When the blowing process reaches 88% of the oxygen supply stage, use the auxiliary lance TSC probe for carbon determination, temperature measurement, and sampling. Then, add some slag-forming material for adjustment based on the determined carbon and measured temperature. Monitor the smelting process based on the auxiliary lance's test results until the smelting process requirements are met before lance removal. At the end of the blowing process, use the auxiliary lance TSO probe for carbon determination, temperature measurement, sampling, and oxygen determination. Before lance removal at the final stage, lower the deep blowing lance position to 900mm and increase the oxygen supply to 32000 Nm³. 3 / h, to perform deep decarburization and homogenize the composition and temperature of molten steel;

[0043] S6. Dust collector ash balls have a certain carbon content. Adding too many during re-blowing will cause a sharp increase in the CO concentration in the flue gas, which will bring the risk of explosion. Therefore, the amount of ash balls added during re-blowing should be controlled at 900 kg. The excess can be replaced with lime or limestone. If the adjustment range is large and more than 1000 kg of dust collector ash balls need to be added, nitrogen curtain operation must be carried out.

[0044] The composition and proportion of the dust collector ash balls in this embodiment are as follows: TFe 82%, CaO 8%, SiO 25%, P 0.18%, S 0.18%, H2O 4.64%, with a surface strength of 800N / piece, and the dust collector ash ball particle size range of 10-50mm accounting for 95%.

[0045] The weight percentages of each component of the desulfurizer in this embodiment are: CaO 85.0%, SiO2 4.0%, CaF 10.97%, S 0.030%, and the particle size of the desulfurizer is 0.2-0.8mm.

[0046] Example 3

[0047] The smelting method includes the following steps in sequence:

[0048] S1. Blast furnace molten iron enters the desulfurization station for desulfurization and slag removal operations. Specifically, the inlet temperature is 1450℃, the desulfurizing agent dosage is 5kg / t, the speed during feeding is 70rpm, the speed after feeding is 100rpm, the stirring time is controlled at 20min, and the desulfurized molten iron is then subjected to slag removal treatment.

[0049] S2. The top and bottom blowing converter is used for smelting. The weight percentage of the raw materials for the main metal material is: 85% iron, the remainder is scrap steel, the iron contains 0.55% Si and 0.45% Mn, the temperature at the desulfurization station is 1500℃, and the slag content is 0.45%.

[0050] S3. The blowing process adopts a low-high-low oxygen supply mode, with the oxygen supply intensity controlled at 4.5 Nm. 3 / (min·t), the bottom-blown argon flow rate is controlled at 0.10 Nm³. 3 / (min·t), the initial blowing ignition gun position is set to 1500mm. After normal ignition, when the blowing reaches 2% of the oxygen supply process, the position is raised to the normal blowing gun position of 1800mm, and the ignition flow rate is 15000Nm. 3 / h, after 45 seconds the oxygen supply will automatically increase in stages to 32000 Nm³. 3 / h, add the first batch of slag-forming materials (including dust removal ash balls and other calcium-based auxiliary materials) 1 minute after the blowing starts. The amount added is 1 / 2 of the total amount added, and symmetrical silos are used for addition. Among them, the dust removal ash balls are mainly added through continuous feeding silos to ensure that the dust removal ash balls are added smoothly and to reduce the carbon-oxygen reaction brought about by the dust removal ash balls.

[0051] S4. When the carbon-oxygen reaction begins, add the second batch of slag-forming material. Depending on the slag formation, follow the principle of adding in multiple batches in small quantities. The amount of dust removal ash balls added per batch is 480 kg. The amount of other slag-forming materials added per batch is also 480 kg. The iron content and cooling effect of the dust removal balls are similar to those of blast furnace return ore, but the slag formation effect is relatively slow. Adjust the lance position and the timing of adding materials during the smelting process according to the actual usage effect. The dust removal ash balls melt relatively slowly. To prevent them from not melting and reducing completely, do not add dust removal ash balls 3 minutes before the end of smelting.

[0052] S5. When the blowing process reaches 90% of the oxygen supply stage, use the auxiliary lance TSC probe for carbon determination, temperature measurement, and sampling. Then, based on the determined carbon and measured temperature, add some slag-forming material for adjustment. Monitor the smelting process based on the auxiliary lance test results until the smelting process requirements are met before lance removal. At the end of the blowing process, use the auxiliary lance TSO probe for carbon determination, temperature measurement, sampling, and oxygen determination. Before lance removal at the final stage, lower the deep blowing lance position to 900mm and increase the oxygen supply to 32000 Nm³. 3 / h, to perform deep decarburization and homogenize the composition and temperature of molten steel;

[0053] S6. Dust collector ash balls have a certain carbon content. Adding too many during re-blowing will cause a sharp increase in the CO concentration in the flue gas, which will bring the risk of explosion. Therefore, the amount of ash balls added during re-blowing should be controlled to ≤1000kg. The excess can be replaced with lime or limestone. If the adjustment range is large and more than 1000kg of dust collector ash balls need to be added, nitrogen curtain operation must be carried out.

[0054] The composition and proportion of the dust collector ash balls in this embodiment are as follows: TFe 82%, CaO 8.12%, SiO2 4.5%, P 0.19%, S 0.19%, H2O 5%, with a surface strength of 800N / piece, and the dust collector ash ball particle size range of 10-50mm accounting for 90%.

[0055] The weight percentages of each component of the desulfurizer in this embodiment are: CaO 90.0%, SiO2 2.0%, CaF 7.97%, S 0.030%, and the particle size of the desulfurizer is 1.0-1.5mm.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for preventing explosions in converter-based smelting of dust-collecting ash balls, characterized in that, The method includes the following steps in sequence: S1. Blast furnace molten iron enters the desulfurization station for desulfurization and slag removal operations; S2. Smelting using a top-and-bottom blown converter; S3. The blowing process adopts a low-high-low oxygen supply operation mode; S3.1 After normal ignition, when the oxygen supply process reaches 2%, the ignition gun is raised to the normal blowing gun position, and the ignition oxygen supply is 15000 Nm. 3 / h, after a period of time, the oxygen supply will be automatically increased in stages to 30000-32000 Nm³. 3 / h, the slag-forming material includes dust removal ash balls and other calcium-based auxiliary materials. After the flame is normal after the start-up, the first batch of slag-forming material is added, and the amount added is 1 / 3-1 / 2 of the total amount. After the first batch of slag-forming material is added, slag-forming material is continuously added. If the flame is abnormal, the addition is stopped in time and added again in time after the flame is normal. The principle of adding material is multiple batches in small quantities. The amount of other calcium-based auxiliary materials added in each batch is 300-500 kg. Ten minutes before smelting, lime is prepared according to the alkalinity requirements. Twelve minutes before smelting, dust removal ash balls are prepared according to the requirements based on the temperature of the molten steel. S3.

2. When the carbon-oxygen reaction begins, add the second batch of slag-forming material, following the principle of multiple batches and small quantities according to the slag formation. During the smelting process, adjust the gun position and feeding timing based on the slag formation effect of the dust removal ash balls. The amount of dust removal ash balls added per batch in the slag-forming material is ≤500kg, and the amount of other calcium-based auxiliary materials added per batch is ≤500kg. The composition and proportion of the dust removal ash balls are: TFe≥50%, CaO≥7%, SiO2≤5%, P≤0.20%, S≤0.20%, H2O≤5%, surface strength≥800N / piece, and the proportion of dust removal ash balls with a particle size range of 10~50mm to the total mass is greater than 90%. S3.3 When the blowing process reaches 85-90% of the oxygen supply stage, use the auxiliary lance TSC probe for carbon determination, temperature measurement, and sampling. Then, add some slag-forming material for adjustment based on the determined carbon and measured temperature. Monitor the smelting process based on the auxiliary lance test results until the smelting process requirements are met before lance removal. At the end of the blowing process, use the auxiliary lance TSO probe for temperature measurement, sampling, and oxygen determination. Before lance removal at the final stage, lower the deep blowing lance position to 900mm and increase the oxygen supply to 32000 Nm³. 3 / h, to perform deep decarburization and homogenize the composition and temperature of molten steel; The dust removal ash balls mentioned in step 3 melt relatively slowly. To prevent them from not melting and reducing completely, the dust removal ash balls should not be added 3 minutes before the end of smelting. The dust collector ash balls mentioned in step 3 have a certain carbon content. Adding too much during re-blowing will cause a sharp increase in the CO concentration in the flue gas, which will bring the risk of explosion. Therefore, the amount of dust collector ash balls added during re-blowing should be controlled to ≤1000kg. The excess can be replaced with lime or limestone. If the adjustment range is large and more than 1000kg of dust collector ash balls need to be added, nitrogen curtain operation must be carried out.

2. The method for preventing explosions in converter digestion and dust removal ash balls according to claim 1, characterized in that: The parameters for the desulfurization operation described in step 1 are as follows: inlet temperature ≥1350℃, desulfurizing agent dosage 4-6kg / t, rotation speed during feeding 60-70rpm, rotation speed after feeding 80-100rpm, and stirring time controlled at 15-20min.

3. The method for preventing explosions in converter smelting by digesting dust and removing ash balls according to claim 1, characterized in that: The raw material composition and weight percentage of the main metal material input in the smelting process described in step 2 are as follows: 80-85% molten iron, with the remainder being scrap steel. The molten iron contains 0.20-0.55% Si, 0.25-0.45% Mn, and ≤0.5% slag.

4. The method for preventing explosions in converter smelting by digesting dust and removing ash balls according to claim 1, characterized in that: In step 3.1, the oxygen supply intensity during the blowing process is controlled at 3.5-4.5 Nm. 3 / (min·t), the bottom-blown argon flow rate is controlled at 0.05-0.10 Nm³. 3 / (min·t), the ignition gun position is set at 1500mm, and the normal blowing gun position is 1400-1800mm. The slag-forming material is added using symmetrical silos, and the dust removal ash balls are added using continuous feeding silos to ensure that the dust removal ash balls are added smoothly and to reduce the carbon-oxygen reaction brought about by the dust removal ash balls.

5. The method for preventing explosions in converter smelting by digesting dust and removing ash balls according to claim 2, characterized in that, The weight percentages of each component of the desulfurizing agent in step 1 are: CaO≥80.0%, SiO2≤5.0%, CaF2≥7.0%, S≤0.040%, and the particle size of the desulfurizing agent is 0.2-1.5mm.