Operation method for opening new converter

Abstract

The invention discloses an operation method for opening a new converter in a converter, which is applied to the field of converter steelmaking and comprises the following steps of: baking the converter after the converter building is finished; 4-6 t of continuous casting residual liquid slag is added into the converter, the converter is rocked forwards to 110-130 DEG C, and the continuous casting residual liquid slag is evenly spread on the converter lining slag surface position of the converter; molten iron is added into the converter, the oxygen lance is controlled to conduct blowing at low oxygen and low lance position, and after ignition is normal, the oxygen pressure of the oxygen lance is restored to the conventional blowing oxygen pressure; adding a first batch of slagging material into the converter, calculating the batch and batch of the slagging material added into the converter according to the heat balance, and adding the residual slagging material according to the batch and batch; and after the end-point components of the converter meet the tapping requirements, slag stopping and tapping are conducted, and deoxidation alloying is conducted. According to the operation method provided by the invention, cyclic utilization of the continuous casting residual liquid slag is realized, the alkalinity of the converter at the early stage of starting a new converter is improved, the waste of heat and resources is avoided, and the cost is effectively reduced.

Description

Technical Field

[0001] The invention relates to the field of converter steelmaking, in particular to an operating method for starting a new converter. Background Art

[0002] The converter lining refers to the refractory material layer built inside the metal shell of the converter. The main function of the converter lining is to provide a durable container for high-temperature metallurgical melt to complete the steelmaking reaction. The lining material is required to be able to withstand high temperatures and drastic temperature fluctuations, chemical erosion by slag, and mechanical impact and wear of molten steel.

[0003] In the related technology, the converter lining is made of alkaline refractory materials, the main material of which is magnesia carbon brick. Magnesia carbon brick is a non-burning carbon composite refractory material made of high-melting-point alkaline oxide magnesia and high-melting-point carbon material that is difficult to be wetted by slag as raw materials, adding various non-oxide additives and combining them with carbonaceous binders.

[0004] Magnesia carbon bricks have good high temperature resistance and strong slag resistance. However, magnesia carbon bricks have poor thermal shock resistance, so when a new furnace is opened, it is necessary to bake the furnace, and then add molten iron for smelting. Since the temperature of the baking process is low and the time cannot be guaranteed, the first furnace of the converter is generally difficult to operate, with large heat loss and high cost.

[0005] Therefore, how to effectively reduce the cost of starting a new converter is a technical problem that technicians in this field currently need to solve. Summary of the invention

[0006] The purpose of the present invention is to provide an operating method for starting a new converter, which is used to reduce costs and save energy.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for operating a new converter, comprising:

[0009] Step S1: after the converter is built, the converter is baked;

[0010] Step S2: adding 4-6t of continuous casting residual liquid slag into the converter, shaking the furnace forward to 110-130 degrees, and evenly spreading the continuous casting residual liquid slag on the lining slag surface of the converter;

[0011] Step S3: adding molten iron into the converter, controlling the oxygen lance to start blowing at a low oxygen pressure and low lance position, and after the ignition is normal, restoring the oxygen pressure of the oxygen lance to the normal blowing oxygen pressure;

[0012] Step S4: after the oxygen lance in the converter is restored to the normal blowing oxygen pressure, the first batch of slag-making material is added into the converter, and the batch and lot of the slag-making material added into the converter are calculated according to the heat balance, and the remaining slag-making material is added according to the batch and lot;

[0013] Step S5: obtaining the end point composition of the converter, and after the end point composition of the converter meets the steel tapping requirements, slag blocking steel tapping and deoxidation alloying are performed.

[0014] On the other hand, the step S1 of baking the converter includes:

[0015] 10-15t of coke is added into the converter, and after the coke is ignited, the oxygen lance is controlled to blow oxygen into the converter, and the oxygen blowing time is ≥40min.

[0016] On the other hand, when blowing oxygen into the converter, the lance position of the oxygen lance is controlled to be 1.2-3.5m, and the oxygen pressure of the oxygen lance is controlled to be 0.25-0.6Mpa.

[0017] On the other hand, the step S1 further comprises:

[0018] Before the coke is added into the converter, the coke is pre-ignited;

[0019] After the converter is baked, the remaining coke in the converter is poured out.

[0020] On the other hand, in step S2, the continuous casting residual liquid slag is ordinary carbon steel slag.

[0021] On the other hand, the step S4 further comprises:

[0022] The slag-making material is controlled to be added to the converter in small batches and multiple batches. The slag-making material includes several slag types. Each slag type is added to the converter once per minute, and the slag type added each time is controlled within 2.0 kg / t; each slag type is added to the converter in sequence.

[0023] In another aspect, the slag-making material comprises lime, dolomite, ore, sintered ore and / or splashed slag;

[0024] In the step S4, adding the first batch of slag-making materials into the converter comprises:

[0025] Add 60% of the total amount of lime into the converter;

[0026] Adding all the dolomite into the converter;

[0027] 40% of the total amount of ore was added to the converter.

[0028] On the other hand, the step S3 also includes:

[0029] The oxygen pressure of the oxygen lance when blowing is controlled to be 0.25-0.40 MPa, and the conventional blowing oxygen pressure is 0.75-0.90 MPa.

[0030] On the other hand, the step S3 also includes:

[0031] 110-130t of molten iron is added into the converter; and the molten iron is controlled to be added into the converter at a low flow rate.

[0032] On the other hand, the step S3 also includes:

[0033] The silicon content in the molten iron is controlled to be 0.30-0.60%, and the temperature of the molten iron is 1300-1450°C.

[0034] On the other hand, the step S4 further comprises:

[0035] The batches and quantities of the slag-making material added to the converter are calculated according to the heat balance; the amount of lime added is determined according to the silicon content of the molten iron and the final alkalinity requirement, the amount of sintered ore added is determined according to the amount of lime added and the molten iron temperature, the amount of dolomite added is 8-11 kg / t, the amount of lime added in the first batch is 70% of the total amount of lime added, the amount of sintered ore added in the first batch is 30% of the total amount of sintered ore added, the remaining lime and sintered ore are added in small batches and in multiple batches, and the maximum amount added each time shall not exceed 2.0 kg / t based on the remaining amount.

[0036] The operating method for starting a new converter provided by the present invention comprises the following steps: step S1: after the converter is built, the converter is baked; step S2: 4-6t of continuous casting residual liquid slag is added into the converter, the furnace is shaken forward to 110-130 degrees, and the continuous casting residual liquid slag is evenly spread on the slag surface of the converter lining; step S3: molten iron is added into the converter, the oxygen gun is controlled to use low oxygen pressure and low gun position for blowing, and after the ignition is normal, the oxygen pressure of the oxygen gun is restored to the conventional blowing oxygen pressure; step S4: after the oxygen gun in the converter is restored to the conventional blowing oxygen pressure, the first batch of slag-making materials is added into the converter, and the batch and batch size of the slag-making materials added into the converter are calculated according to the heat balance, and the remaining slag-making materials are added according to the batch and batch size; step S5: the terminal composition of the converter is obtained, and after the terminal composition of the converter meets the steel-making requirements, slag is blocked for steel-making, and deoxidation and alloying are performed. The operating method for starting a new converter provided by the present invention recycles the liquid slag left over from continuous casting, utilizes the CaO and temperature therein to promote slagging of the slag in the converter, recovers the metal therein, reduces the difficulty of starting a new converter, realizes the recycling of the liquid slag left over from continuous casting, improves the basicity of the converter in the early stage of starting a new converter, and avoids the waste of heat and resources; adopting the operating method, by improving the slagging effect in the early stage of starting a new converter, the consumption of lime is significantly reduced, the dephosphorization effect of the converter is significantly improved, the cost is effectively reduced, and the competitiveness is improved.

[0037] In one embodiment, step S4 further includes: controlling the slag-making material to be added to the converter in small batches and multiple batches, the slag-making material includes several types of slag, each type of slag is added to the converter once per minute, and the type of slag added each time is controlled within 2.0 kg / t; each type of slag is added to the converter in sequence. The above process can effectively avoid a significant decrease in the temperature in the converter by controlling the slag-making material to be added to the converter in small batches and multiple batches, and controlling the type of slag added each time to be within 2.0 kg / t, thereby avoiding affecting the reaction rate in the converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 A flowchart of a specific implementation method of the method for starting a new converter provided by the present invention;

[0040] Figure 2 The present invention is a flow chart of another specific implementation of the method for operating a new converter provided by the present invention. DETAILED DESCRIPTION

[0041] The core of the present invention is to provide an operating method for starting a new converter, which can reduce material consumption and improve dephosphorization effect.

[0042] In order to enable those skilled in the art to better understand the solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0043] Please refer to Figure 1 and Figure 2 , Figure 1 A flowchart of a specific implementation method of the method for starting a new converter provided by the present invention; Figure 2 The present invention is a flow chart of another specific implementation of the method for operating a new converter provided by the present invention.

[0044] In this embodiment, if Figure 1 As shown, the operation method of starting a new converter furnace includes:

[0045] Step S1: After the converter is built, the converter is baked;

[0046] Step S2: adding 4-6t of continuous casting residual liquid slag into the converter, shaking the furnace forward to 110-130 degrees, and evenly spreading the continuous casting residual liquid slag on the lining slag surface of the converter;

[0047] Step S3: adding molten iron into the converter, controlling the oxygen lance to start blowing with low oxygen pressure and low lance position, and after the ignition is normal, restoring the oxygen pressure of the oxygen lance to the normal blowing oxygen pressure;

[0048] Step S4: after the oxygen lance in the converter is restored to the normal blowing oxygen pressure, the first batch of slag-making material is added into the converter, and the batch and lot of the slag-making material added into the converter are calculated according to the heat balance, and the remaining slag-making material is added according to the batch and lot;

[0049] Step S5: obtaining the final composition of the converter, and after the final composition of the converter meets the steel-making requirements, slag blocking steel-making is performed, and deoxidation and alloying are performed.

[0050] Specifically, the operating method of starting a new converter is mainly to utilize the converter splashing slag, that is, the beneficial lime and metal in the liquid slag left over from continuous casting to recycle and utilize, thereby reducing the cost of the steelmaking process. In step S2, 4-6t of continuous casting residual liquid slag is added into the converter, so that the continuous casting residual liquid slag can be completely spread on the lining slag surface of the converter. If the continuous casting residual liquid slag is too much, it will cause more red slag at the bottom of the converter, and splashing will occur easily during the process of adding molten iron. If the continuous casting residual liquid slag is too little, it cannot cover the lining slag surface of the converter. Therefore, the weight of the continuous casting residual liquid slag is 4-6t, and 5t can be selected for the best effect. In step S2, after the continuous casting residual liquid slag is added into the converter, in order to ensure that the continuous casting residual liquid slag is quickly and evenly covered on the lining slag surface of the converter, the method of shaking the furnace forward to 110-130° is adopted, which can ensure that the continuous casting residual liquid slag is completely spread, and can avoid the continuous casting residual liquid slag flowing out of the furnace mouth of the converter due to the excessive shaking angle of the furnace; the effect is best when the angle of shaking the furnace forward is 120°; the choice of shaking the furnace forward is to ensure that when adding molten iron into the converter, Protect the slag surface; in step S4, after the oxygen lance in the converter returns to the normal blowing oxygen pressure, the first batch of slag-making material is added to the converter, and the amount of the first batch of slag-making material can be appropriately increased to ensure the early slagging effect; then the batches and batch sizes of the slag-making material added to the converter are calculated according to the heat balance, so as to achieve a balance between batches and batch sizes, while meeting the production efficiency and reducing the impact on the temperature in the converter; specifically, the batches and batch sizes of the slag-making material added to the converter can be determined according to the single slag type in the slag-making material, and when adding slag-making material to the converter, each slag type should be added to the converter one by one to avoid interaction between the slag types and factors that are not conducive to production; when each slag type in the slag-making material is added to the converter, the interval time can be within 1 minute, which can meet the full reaction of the previous slag type while ensuring a faster production rhythm.

[0051] The operating method for starting a new converter provided by the present invention recycles the liquid slag left over from continuous casting, utilizes the CaO and temperature therein to promote slagging of the slag in the converter, recovers the metal therein, reduces the difficulty of starting a new furnace, realizes the recycling of the liquid slag left over from continuous casting, improves the basicity of the converter in the early stage of starting a new furnace, and avoids the waste of heat and resources; by adopting the operating method, by improving the slagging effect in the early stage of starting a new converter, the consumption of lime is significantly reduced, the dephosphorization effect of the converter is significantly improved, the cost is effectively reduced, and the competitiveness is improved.

[0052] In some embodiments, baking the converter in step S1 includes:

[0053] Add 10-15t of coke into the converter, and after igniting the coke, control the oxygen gun to blow oxygen into the converter, and the oxygen blowing time is ≥40min. Specifically, the amount of coke added to the converter can be set according to actual production needs. If the amount of coke is too small, it will lead to insufficient heat in the converter and fail to achieve a good oven baking effect. If the amount of coke is too much, it is easy to cause incomplete combustion of coke, and the remaining coke will accumulate at the bottom of the converter, resulting in poor baking effect at the bottom of the converter. Therefore, in order to achieve a good oven baking effect, the amount of coke added to the converter is selected to be 10-15t; at the same time, the oxygen blowing time is controlled to be ≥40min to ensure that the coke can be fully burned and avoid accumulation problems caused by incomplete combustion of coke.

[0054] In some embodiments, when blowing oxygen in the converter, the oxygen lance position is controlled to be 1.2-3.5m, and the oxygen pressure of the oxygen lance is controlled to be 0.25~0.6Mpa. Specifically, the oxygen lance position refers to the distance between the end face of the oxygen lance nozzle and the liquid surface of the molten pool. By controlling the oxygen lance position to be 1.2-3.5m, this height can utilize the impact area of ​​oxygen to make the coke burn quickly; if the oxygen lance position is too low, the oxygen airflow will impact the bottom of the furnace, and if the oxygen lance position is too high, the combustion speed of the coke will be slow, which is not conducive to production. Therefore, the oxygen lance position is selected between 1.2-3.5m; in addition, in order to ensure that the coke will not be blown away during the combustion process and to ensure the combustion speed, the oxygen pressure of the oxygen lance is selected to be 0.25~0.6Mpa.

[0055] In some embodiments, step S1 further includes: igniting the coke before adding it to the converter; and pouring out the remaining coke in the converter after the converter is baked. Specifically, before adding the coke to the converter, the coke is placed in a scrap steel bucket and ignited in advance, thereby improving the combustion efficiency of the coke after being placed in the converter.

[0056] In some embodiments, in step S2, the liquid slag after continuous casting is ordinary carbon steel slag. Specifically, since the lining filling material of the converter contains more water, the hydrogen element added to the molten steel is relatively large, which is not suitable for producing steel with requirements for hydrogen content. Therefore, ordinary carbon steel is selected as the liquid slag after continuous casting to meet the converter opening effect.

[0057] In some embodiments, step S4 further includes:

[0058] The slag-making materials are added to the converter in small batches and in multiple batches. The slag-making materials include several types of slag. Each type of slag is added to the converter once per minute, and the type of slag added each time is controlled within 2.0 kg / t; each type of slag is added to the converter in sequence.

[0059] In the above process, by controlling the slag-making material to be added to the converter in small batches and multiple batches, and controlling the type of slag added each time within 2.0 kg / t, it is possible to effectively avoid a significant drop in temperature in the converter, thereby avoiding affecting the reaction rate in the converter.

[0060] In some embodiments, the slag type in the slag making material is lime, dolomite, ore, sintered ore and / or splashed slag;

[0061] In step S4, adding the first batch of slag-making materials into the converter includes: adding 60% of the total amount of lime into the converter; adding all the dolomite into the converter; adding 40% of the total amount of ore into the converter; the first batch of slag-making materials added to the converter is relatively large in quantity to ensure the early slag-making effect.

[0062] In some implementations, step S3 further includes:

[0063] The oxygen pressure of the oxygen lance is controlled to be 0.25~0.40Mpa when it is opened, and the oxygen pressure of conventional blowing is 0.75~0.90Mpa. Specifically, the low oxygen pressure in the early stage of blowing can prevent the explosion accident of dry dust removal. If it is too high, it is easy to explode, and if it is too low, the iron oxide will gather and splash in the early stage. The conventional blowing oxygen pressure of 0.75~0.90Mpa is obtained in daily production.

[0064] In some implementations, step S3 further includes:

[0065] Add 110-130t of molten iron into the converter; control the molten iron to be added to the converter at a low flow rate; reduce the erosion of the slag surface by the molten iron. Specifically, according to the capacity of the ladle, select the appropriate weight of molten iron to add to the converter. For example, 120t of molten steel can be selected. 120t is the nominal capacity of the converter, and the matching ladle capacity is appropriate to create conditions for the next process operation.

[0066] In some embodiments, step S3 further includes: controlling the silicon content in the molten iron to be between 0.30 and 0.60%, and the temperature of the molten iron to be between 1300 and 1450° C. Specifically, the silicon content in the molten iron will affect the furnace opening operation of the converter. If the silicon content in the molten iron is too low, the slag slagging effect in the converter will be poor. If the silicon content in the molten iron is too high, it will easily cause the molten iron to splash. Therefore, the silicon content in the molten iron is selected to be between 0.30 and 0.60%. Regarding the selection of the molten iron temperature, if the temperature of the molten iron added to the converter is too low, the physical heat of the molten iron will be low. If the temperature of the molten iron is too high, the early reaction speed will be fast, the amount of ore added will be large, and it will be easy to splash.

[0067] Specifically, Figure 2 As shown, in a specific embodiment, a method for operating a converter to start a new furnace of the present invention comprises:

[0068] Step S1: After the converter is built, 10-15t of coke is added into the converter, and after the coke is ignited, the oxygen lance is controlled to blow oxygen into the converter, and the oxygen blowing time is ≥40min, so as to dry the converter;

[0069] Step S2: adding 5 tons of continuous casting residual liquid slag into the converter, shaking the furnace forward to 120 degrees, and evenly spreading the continuous casting residual liquid slag on the lining slag surface of the converter;

[0070] Step S3: adding 120t of molten iron into the converter, controlling the oxygen lance to start blowing at a low oxygen pressure and low lance position, and after the ignition is normal, restoring the oxygen pressure of the oxygen lance to the normal blowing oxygen pressure;

[0071] Step S4: after the oxygen lance in the converter is restored to the normal blowing oxygen pressure, the first batch of slag-making material is added into the converter, and the batch and lot of the slag-making material added into the converter are calculated according to the heat balance, and the remaining slag-making material is added according to the batch and lot;

[0072] Step S5: obtaining the final composition of the converter, and after the final composition of the converter meets the steel-making requirements, slag blocking steel-making is performed, and deoxidation and alloying are performed.

[0073] Specifically, in a specific embodiment, a method for operating a new converter of the present invention includes:

[0074] Step S1: After the converter is built, 10-15t of coke is added into the converter, and oxygen is blown into the converter for more than 40 minutes after ignition. After the furnace is baked, the remaining coke in the converter is poured out; wherein the coke is ignited in the scrap steel bucket in advance, the oxygen supply gun is at a position of 1.2-3.5m, and the oxygen pressure is 0.25-0.6Mpa;

[0075] Step S2: adding 5 tons of continuous casting residual liquid slag into the converter, shaking the furnace forward to 120 degrees, and evenly spreading the continuous casting residual liquid slag on the slag surface of the converter lining; wherein the steel grade of the continuous casting residual liquid slag is ordinary carbon steel;

[0076] Step S3: Add 120t of molten iron into the converter, use low oxygen pressure and low gun position to start blowing, and after the ignition is normal, restore the normal blowing oxygen pressure; wherein, the molten iron is added slowly with a small flow to reduce the erosion of the slag surface by the molten iron, the silicon content of the molten iron is controlled at 0.30-0.60%, the temperature of the molten iron is 1300-1450℃, the oxygen pressure of the start blowing is controlled at 0.25-0.40Mpa, and after the ignition is normal, the normal blowing oxygen pressure is 0.75-0.90Mpa;

[0077] Step S4: After the oxygen pressure of conventional blowing is restored, the first batch of lime, dolomite, ore and other slag-making materials are added to the converter, and the remaining slag is added in batches according to the heat balance calculation; wherein, the lime, sintered ore and splashing slag in the slag-making materials should be added in small batches and multiple batches, and the amount added each time should be controlled within 2.0 kg / t to avoid concentrated addition causing a sudden low temperature in the converter. Lime, sintered ore and splashing slag should be added in sequence to avoid adding more than two at the same time to reduce reactions and adverse effects;

[0078] Step S5: The final composition of the converter returns to meet the tapping requirements, slag blocking and tapping are started, and deoxidation and alloying are performed.

[0079] Specifically, according to the above control method, a new furnace is opened in a 120t converter as an example, and the control situation is shown in Table 1.

[0080] In Table 1, the embodiment is the control parameters and material consumption statistics when the operating method of the converter provided by the present invention is used, and the comparative example is the control parameters and material consumption statistics when the operating method of the converter provided by the related art is used. It can be seen from the data in Table 1 that the operating method of the converter provided by the present invention can achieve stable smelting of the converter, and the consumption of lime is reduced by 6kg / t and the consumption of steel materials is reduced by 3kg / t compared with the related art, which realizes the recovery of beneficial resources, is conducive to reducing the cost of the converter and improving the competitiveness of the enterprise.

[0081] Table 1 Control parameters and material consumption statistics

[0082] Weight of molten iron, t Silicon in hot metal, % Phosphorus in hot metal, % Molten iron temperature, ℃ Lime, kg / t Oxygen supply time, min End point carbon, % End point phosphorus, % Dephosphorization rate Slag basicity Steel material consumption, kg / t Example 120 0.41 0.126 1362 25 16 0.08 0.015 88.10% 3.12 1062 Comparative Example 120 0.45 0.125 1355 31 15 0.06 0.020 84.00% 2.95 1065

[0083] In some implementations, step S4 further includes:

[0084] The batches and quantities of slag-making materials added to the converter are calculated based on the heat balance; the amount of lime added is determined based on the silicon content of the molten iron and the final alkalinity requirements, and the amount of sintered ore added is determined based on the amount of lime added and the temperature of the molten iron. The amount of dolomite added is 8-11kg / t, the amount of lime added in the first batch is 70% of the total amount of lime added, and the amount of sintered ore added in the first batch is 30% of the total amount of sintered ore added. The remaining lime and sintered ore are added in small batches and multiple batches, and the maximum amount added each time is no more than 2.0kg / t based on the remaining amount. Since silicon in the molten iron reacts first, the addition of the first batch of materials will not affect the carbon-oxygen reaction in the furnace; the second batch of slag-making materials are generally added during the carbon-oxygen reaction. If they are added more concentratedly, the temperature in the furnace will drop sharply, inhibiting the carbon-oxygen reaction, and FeO in the slag will gather and splash. After the slag in the furnace is sprayed out, the alkalinity will be reduced, affecting the dephosphorization effect.

[0085] Regarding the batch and amount of slag-making materials added to the converter, the relevant technology includes the following processes:

[0086] 1. 15t of coke is pre-ignited in the scrap steel bucket. After the converter is built, coke is added into the furnace. The oxygen gun is lowered to 3.9m and oxygen ignition is started. The oxygen pressure is 0.30Mpa. The gun is lowered by 0.5m every 5 minutes, and the oxygen pressure is increased by 0.05Mpa until the lowest gun position is 1.2m. The oxygen pressure reaches a maximum of 0.6Mpa. Oxygen is blown into the furnace for 53 minutes. After the furnace is baked, the remaining coke in the furnace is poured out.

[0087] 2. Add 5.2t of ordinary carbon steel continuous casting residual hot slag into the furnace, shake the furnace forward to 120°, and spread the hot slag evenly on the slag surface of the furnace lining;

[0088] 3. Add 120t of molten iron into the furnace, with 0.45% silicon in the molten iron, and the temperature of the molten iron is 1410℃. The oxygen pressure at the start of blowing is 0.40Mpa. After the ignition is normal, the process oxygen pressure is 0.85Mpa.

[0089] 4. According to the alkalinity requirement and heat balance, the total amount of slag materials added is calculated, 4215kg of lime, 1076kg of dolomite, and 3511kg of sintered ore. After returning to normal blowing oxygen pressure, add the first batch of lime 2950kg, dolomite 1076kg, and ore 1053kg into the furnace, and add the remaining lime and sintered ore after 5 minutes. The process is severely splashed;

[0090] 5. The final composition of the converter returns to high phosphorus, which does not meet the requirements for steelmaking. After adding lime and blowing, re-sampling is carried out. After meeting the requirements, slag blocking and steelmaking are started, and deoxidation and alloying are carried out.

[0091] In the specific embodiment 1 of the present application, the following process is included:

[0092] 1. Coke 10-13t, 12t is available, pre-ignited in the scrap steel bucket, after the converter is built, add coke into the furnace, lower the oxygen gun to the gun position 3-4m, such as 3.5m, open oxygen ignition, oxygen pressure 0.2-0.3Mpa, such as 0.25Mpa, every 4-6 minutes, such as 5 minutes, lower the gun 0.5m, oxygen pressure increases 0.05Mpa, until the lowest gun position is 1.1-1.3m, such as 1.2m, oxygen pressure up to 0.6Mpa, blow oxygen into the furnace for 40-50min, such as 45min, after the furnace is baked, pour out the remaining coke in the furnace;

[0093] 2. Add 4.5-5.5t, such as 5t, of ordinary carbon steel continuous casting residual hot slag into the furnace, shake the furnace forward to 110-130°, such as 120°, and spread the hot slag evenly on the slag surface of the furnace lining;

[0094] 3. Add 110-130t of molten iron into the furnace, such as 120t, 0.25-0.35% silicon in molten iron, such as 0.30%, 1300-1400℃, such as 1350℃, 0.3-0.4Mpa oxygen pressure at the start of blowing, such as 0.35Mpa, after normal ignition, the process oxygen pressure is 0.7-0.9Mpa, such as 0.80Mpa;

[0095] 4. Calculate the total amount of slag-making materials added according to the alkalinity requirement and heat balance, including 2842kg lime, 1053kg dolomite and 2123kg sintered ore. After returning to normal blowing oxygen pressure, add the first batch of 1989kg lime, 1053kg dolomite and 637kg ore into the converter. Add the remaining lime and sintered ore at a rate of 1.5kg / t each time, once every minute, until all are added.

[0096] 5. The final composition of the converter returns to the standard and meets the tapping requirements, slag tapping begins, and deoxidation and alloying are carried out;

[0097] In Example 2 of the present application, the following process is included:

[0098] 1. 14t of coke is pre-ignited in the scrap steel bucket. After the converter is built, coke is added into the furnace. The oxygen gun is lowered to 3.7m and oxygen ignition is started. The oxygen pressure is 0.25Mpa. The gun is lowered by 0.5m every 5 minutes, and the oxygen pressure is increased by 0.05Mpa until the lowest gun position is 1.2m. The oxygen pressure reaches a maximum of 0.6Mpa. Oxygen is blown into the furnace for 50 minutes. After the furnace is baked, the remaining coke in the furnace is poured out.

[0099] 2. Add 5.5t of ordinary carbon steel continuous casting residual hot slag into the furnace, shake the furnace forward to 120°, and spread the hot slag evenly on the slag surface of the furnace lining;

[0100] 3. Add 120t of molten iron into the furnace, with 0.60% silicon in the molten iron, and the molten iron temperature is 1450℃. The oxygen pressure at the start of blowing is 0.40Mpa. After the ignition is normal, the process oxygen pressure is 0.90Mpa.

[0101] 4. Calculate the total amount of slag materials added according to the alkalinity requirement and heat balance, with 5736kg lime, 1138kg dolomite and 5342kg sinter. After returning to normal blowing oxygen pressure, add the first batch of 4015kg lime, 1138kg dolomite and 1603kg ore into the furnace, and add the remaining lime and sinter at 2.0kg / t each time, once every minute, until all are added;

[0102] 5. When the final composition of the converter returns to the standard and meets the requirements for steelmaking, slag blocking and steelmaking are started, and deoxidation and alloying are carried out.

[0103] The above is a detailed introduction to the operating method of opening a new converter provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A method for operating a new converter, characterized in that: include: Step S1: after the converter is built, the converter is baked; Step S2: adding 4-6t of continuous casting residual liquid slag into the converter, shaking the furnace forward to 110-130 degrees, and evenly spreading the continuous casting residual liquid slag on the lining slag surface of the converter; Step S3: adding molten iron into the converter, controlling the oxygen lance to start blowing at a low oxygen pressure and low lance position, and after the ignition is normal, restoring the oxygen pressure of the oxygen lance to the normal blowing oxygen pressure; Step S4: after the oxygen lance in the converter is restored to the normal blowing oxygen pressure, the first batch of slag-making material is added into the converter, and the batch and lot of the slag-making material added into the converter are calculated according to the heat balance, and the remaining slag-making material is added according to the batch and lot; Step S5: obtaining the end point composition of the converter, and after the end point composition of the converter meets the steel tapping requirements, slag blocking steel tapping and deoxidation alloying are performed.

2. The operating method for starting a new converter according to claim 1, characterized in that: The step S1 of baking the converter comprises: 10-15t of coke is added into the converter, and after the coke is ignited, the oxygen lance is controlled to blow oxygen into the converter, and the oxygen blowing time is ≥40min.

3. The method for operating a new converter according to claim 2, characterized in that: When blowing oxygen in the converter, the lance position of the oxygen lance is controlled to be 1.2-3.5m, and the oxygen pressure of the oxygen lance is controlled to be 0.25-0.6Mpa.

4. The operating method for starting a new converter according to claim 2, characterized in that: The step S1 further comprises: Before the coke is added into the converter, the coke is pre-ignited; After the converter is baked, the remaining coke in the converter is poured out.

5. The operating method for starting a new converter according to claim 1, characterized in that: In the step S2, the continuous casting residual liquid slag is ordinary carbon steel slag.

6. The operating method for starting a new converter according to any one of claims 1 to 5, characterized in that: The step S4 further comprises: The slag-making material is controlled to be added to the converter in small batches and multiple batches. The slag-making material includes several slag types. Each slag type is added to the converter once per minute, and the slag type added each time is controlled within 2.0 kg / t; each slag type is added to the converter in sequence.

7. The operating method for starting a new converter according to claim 6, characterized in that: The slag-making material includes lime, dolomite, ore, sintered ore and / or splashed slag; In the step S4, adding the first batch of slag-making materials into the converter comprises: Add 60% of the total amount of lime into the converter; Adding all the dolomite into the converter; 40% of the total amount of ore was added to the converter.

8. The method for starting a new converter according to any one of claims 1 to 5, characterized in that: The step S3 also includes: The oxygen pressure of the oxygen lance when blowing is controlled to be 0.25-0.40 MPa, and the conventional blowing oxygen pressure is 0.75-0.90 MPa.

9. The operating method for starting a new converter according to claim 8, characterized in that: The step S3 also includes: Adding 110-130 tons of molten iron into the converter; controlling the molten iron to be added into the converter at a low flow rate; The step S3 also includes: The silicon content in the molten iron is controlled to be 0.30-0.60%, and the temperature of the molten iron is 1300-1450°C.

10. The method for starting a new converter according to any one of claims 1 to 5, characterized in that: The step S4 further comprises: The batches and quantities of the slag-making material added to the converter are calculated according to the heat balance; the amount of lime added is determined according to the silicon content of the molten iron and the final alkalinity requirement, the amount of sintered ore added is determined according to the amount of lime added and the molten iron temperature, the amount of dolomite added is 8-11 kg / t, the amount of lime added in the first batch is 70% of the total amount of lime added, the amount of sintered ore added in the first batch is 30% of the total amount of sintered ore added, the remaining lime and sintered ore are added in small batches and in multiple batches, and the maximum amount added each time shall not exceed 2.0 kg / t based on the remaining amount.

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