阅读说明：本技术 一种全铁水冶炼控制喷溅的方法 (Method for controlling splashing in full molten iron smelting ) 是由 邱在军 邓勇 廖彬 韩宝 李海波 黄传根 张小林 蒋林 王雨 杜克斌 李斌斌 于 2021-09-01 设计创作，主要内容包括：本发明公开了一种全铁水冶炼控制喷溅的方法,属于冶金转炉炼钢领域。本发明包括以下步骤：S1、上一炉出完钢后,翻渣并保留一定渣量,溅渣护炉,然后兑铁水；根据装入铁水量计算石灰加入量、生白云石加入量、烧结矿加入量；S2、下枪开吹前,先加入部分烧结矿,并进行底吹强搅拌和摇炉处理；S3、下枪开始冶炼,根据累计供氧量分批次加料；并对应调整氧枪枪位和氧枪流量。本发明针对现有技术中全铁水冶炼冶炼容易发生喷溅的情况,拟提供一种全铁水冶炼控制喷溅的方法,可以改善碳氧不均衡反应,有效遏制全铁水冶炼时喷溅的发生,降低铁钢比和钢铁料消耗。(The invention discloses a method for controlling splashing in full molten iron smelting, belonging to the field of metallurgical converter steelmaking. The invention comprises the following steps: s1, after steel is discharged from the previous furnace, turning over slag and keeping a certain amount of slag, splashing slag to protect the furnace, and then adding molten iron; calculating the addition amount of lime, the addition amount of raw dolomite and the addition amount of sinter according to the amount of the charged molten iron; s2, before the gun is put and the furnace is opened, adding part of sinter, and carrying out bottom blowing strong stirring and furnace shaking treatment; s3, putting the lance into the furnace to start smelting, and feeding the materials in batches according to the accumulated oxygen supply amount; and correspondingly adjusting the lance position and the flow of the oxygen lance. Aiming at the condition that the splashing is easy to occur in the full molten iron smelting in the prior art, the invention provides the method for controlling the splashing in the full molten iron smelting, which can improve the carbon-oxygen imbalance reaction, effectively restrain the occurrence of the splashing in the full molten iron smelting and reduce the iron-steel ratio and the iron-steel material consumption.)

1. A method for controlling splashing in full molten iron smelting is characterized in that: the method comprises the following steps:

s1, after steel is discharged from the previous furnace, turning over slag and keeping a certain amount of slag, splashing slag to protect the furnace, and then adding molten iron; calculating the addition amount of lime, the addition amount of raw dolomite and the addition amount of sinter according to the amount of the charged molten iron;

s2, before the gun is put and the furnace is opened, adding part of sinter, and carrying out bottom blowing strong stirring and furnace shaking treatment;

s3, putting the lance into the furnace to start smelting, and feeding the materials in batches according to the accumulated oxygen supply amount; and correspondingly adjusting the lance position and the flow of the oxygen lance.

2. The method of controlling splashing in the smelting of all-molten iron according to claim 1, wherein: in step S1, the amount of the slag is controlled to be 10 +/-5 t.

3. The method of controlling splashing in the smelting of all-molten iron according to claim 1, wherein: the molten iron blended in the step S1 comprises the following components in percentage by mass: c: 4.40% -4.80%, Si: 0.20% -0.50%, Mn: 0.12% -0.18%, P: 0.090% -0.155%, S: 0.001% -0.040%, V: 0.025 to 0.065 percent of Ti, 0.034 to 0.118 percent of Ti, and the balance of iron and inevitable impurities.

4. The method of controlling splashing in the smelting of all-molten iron according to claim 1, wherein: in step S2, before the lower gun is opened, 90% +/-5% of sinter ore is added in a continuous casting mode with a vibration frequency of 40Hz-50Hz, bottom blowing strong stirring is carried out, and the flow rate of bottom blowing nitrogen is 1980 +/-100 m³And/h, and the furnace was shaken in the order of 0 ° → 50 ° ± 10 ° → 330 ° ± 10 ° → 0 °.

5. The method of controlling splashing in the smelting of all molten iron according to claim 4, wherein: the batch charging process in the step S3 is as follows: under oxygen supply of 200m³-500m³Adding a first batch: 80% +/-5% lime, 80% +/-5% raw dolomite, oxygen supply 2500m³-2800m³A second batch was added: 20% +/-5% lime and 20% +/-5% raw dolomite; the rest 10% +/-5% of the sinter ore is supplied with oxygen to 6000m³The mixture is continuously fed into the furnace in a vibration frequency of 25Hz-30 Hz.

6. A method for controlling splashing in the smelting of whole molten iron according to any one of claims 1 to 5, characterized in that: the control process of the oxygen lance position in the step S3 is as follows: oxygen supply 0m³-6000m³When the oxygen lance position is 1.90 +/-0.05 m, oxygen is supplied at 6000m³And after the measurement of the sublance TSC is finished, the oxygen lance position is 2.10 +/-0.15 m, and the oxygen lance position at the end of the measurement of the sublance TSC and the smelting is 1.80 +/-0.05 m.

7. According to claim6 the method for controlling splashing in the smelting of the whole molten iron is characterized in that: the control process of the oxygen lance flow in the step S3 is as follows: oxygen supply 0m³-3000m³While, the oxygen lance flow rate is 58000 +/-1000 m³H, oxygen supply 3000m³-6000m³Time, oxygen lance flow rate is 56000 +/-1000 m³H, oxygen supply 6000m³500m before measuring the TSC of the sublance³While, the oxygen lance flow rate is 63000 +/-500 m³H, 500m before measuring the TSC of the sublance³After the TSC measurement of the sublance, the oxygen lance oxygen supply flow rate is 35000 +/-500 m³H, oxygen supply flow of oxygen lance at smelting end point of 63000 +/-500 m after TSC measurement of sublance³/h。

8. The method of controlling splashing in the smelting of all-molten iron according to claim 7, wherein: in step S3, the sole blowing flow rate is controlled as follows: oxygen supply of 0-3000m³While, the flow rate of bottom-blown nitrogen is 1188 +/-100 m³H, oxygen supply 3000m³End of measurement of the sublance TSC with a bottom-blowing argon flow of 594. + -.50 m³The flow rate of bottom blowing argon at the end of measuring the TSC of the sublance and the smelting end point is 1980 +/-100 m³/h。

Technical Field

The invention relates to the technical field of metallurgical converter steelmaking, in particular to a method for controlling splashing in full molten iron smelting.

Background

The main reason for the occurrence of the converter smelting splash is the unbalanced reaction of carbon and oxygen, which releases a large amount of CO gas instantly to spray liquid metal and slag out of the furnace mouth. Converter smelting reaches a critical point generally within 3-5min, the carbon-oxygen reaction speed reaches a maximum value, a large amount of CO gas is generated under the condition, and the huge stirring energy is 5-9 times of the energy of an oxygen stream. The CO gas stirring energy is the main power for pushing molten steel and slag in the converter to splash. Because the carbon-oxygen reaction is very sensitive to the temperature, the carbon-oxygen reaction is inhibited when the temperature is lower than 1470 ℃, and the carbon-oxygen reaction is violent when the temperature is higher than 1470 ℃. If the temperature-reducing material is added too intensively and too quickly in the smelting process of the converter, the temperature of a molten pool is lower than 1470 ℃, the temperature in the converter rises along with the increase of heat generated by carbon-oxygen reaction, so that a large amount of FeO is accumulated in molten slag, and the foaming of the molten slag is serious due to the increase of oxidizability, so that the discharge of CO gas is blocked.

The splashing is a condition frequently encountered during converter smelting, and particularly during smelting of full molten iron, as no scrap steel exists, the temperature is quickly raised, the time for adding cold materials in the smelting process is short, the adding amount of the cold materials is large, the requirement on the skill level of operators is extremely high, and the explosive splashing is easily caused in the early stage of smelting. Impact of splashing: (1) a large amount of yellow smoke is produced and is discharged out of a factory building to cause environmental pollution; (2) the steel tapping amount is reduced, so that the consumption of steel materials is increased, and the post process cannot process continuous casting and unplanned broken casting when the steel tapping amount is seriously insufficient; (3) molten iron enters a furnace pit, the operation of the furnace pit is difficult to process, and meanwhile, the molten iron takes away heat, so that the end point temperature in the furnace is insufficient, and the end point of the molten steel is over oxidized; (4) the furnace lining is seriously washed, and equipment such as a gun, a burning gun, a furnace mouth, a smoke hood slag and the like are damaged and scald operators. Under the situation that the environmental protection policy is continuously tightened, steel enterprises need to make environmental protection work, and can gain better development without firmly moving the way of ecological priority and green development. The prevention and reduction of splashing generated during the smelting of the full molten iron are very important and urgent.

Through retrieval, the application with the application number of 2017107434081 discloses a smelting control method of a full-scale molten iron converter, which comprises the following control methods: the process comprises the steps of deslagging, calculating the total amount of ore and molten iron, controlling iron charging, controlling oxygen supply, controlling slag formation, controlling temperature and controlling an end point. The application helps to avoid splashing in the process of smelting the total iron, but the ore is spread before water is added, if the ore is not spread, the fire is large during water adding, the possibility of splashing may exist during water adding, and the iron adding speed is limited to be not fast. Also, for example, application No. 2014105152458 discloses a method for controlling splashing during the decarburization period of less slag smelting of a converter, which comprises the following steps; adding scrap steel and molten iron, blowing and desilicifying and dephosphorizing in a converter, pouring early-stage slag, blowing and decarburizing in the converter, tapping in the converter, and remaining slag. This application is through the addition of control converter converting decarbonization period lime stone or dolomite, and control oxygen suppliment intensity progressively increases when blowing down the rifle, and the adjustment through rifle position height and oxygen suppliment intensity among the converting process has fine control the explosive splash when rifle converting under the decarbonization period and the back dry splash problem of converting process, nevertheless need the operation of slagging-off. And then as the application with the application number of 2018103543169, a method for inhibiting splashing in the converter steelmaking process is disclosed, firstly, the adding amount of cold materials of scrap steel and the adding condition of a first batch of blowing are determined, and when the oxidation period of silicon and manganese is over, the alkalinity range of the steel slag is 1.4-1.9, MgO 5-7%, TFe 18-24% and the temperature of molten iron 1390-1420 ℃; adding slag-making materials containing calcium and magnesium and cold materials containing iron oxides in batches at a first carbon-phosphorus oxidation reaction selection point, wherein the alkalinity range of the steel slag is 2.8-3.5, the MgO content in the slag is 7% -10%, and the TFe content is 15% -20% at a second carbon-phosphorus oxidation reaction selection point; and performing gun pressing operation in the later stage of converting. The application ensures that the slagging process is adaptive to the molten iron reaction process during converter blowing, is beneficial to relieving the splashing problem in the converter steelmaking process, and has a further optimized space in practice.

Disclosure of Invention

1. Technical problem to be solved by the invention

The invention aims to provide a method for controlling splashing in the smelting of full molten iron aiming at the condition that the splashing is easy to occur in the smelting of the full molten iron in the prior art, which can improve carbon-oxygen imbalance reaction, effectively restrain the occurrence of splashing in the smelting of the full molten iron and reduce iron-steel ratio and iron-steel material consumption.

2. Technical scheme

In order to achieve the purpose, the technical scheme provided by the invention is as follows:

the invention relates to a method for controlling splashing in total molten iron smelting, which comprises the following steps:

s1, after steel is discharged from the previous furnace, turning over slag and keeping a certain amount of slag, splashing slag to protect the furnace, and then adding molten iron; calculating the addition amount of lime, the addition amount of raw dolomite and the addition amount of sinter according to the amount of the charged molten iron;

s2, before the gun is put and the furnace is opened, adding part of sinter, and carrying out bottom blowing strong stirring and furnace shaking treatment;

s3, putting the lance into the furnace to start smelting, and feeding the materials in batches according to the accumulated oxygen supply amount; and correspondingly adjusting the lance position and the flow of the oxygen lance.

Further, the amount of the slag remaining in step S1 is controlled to 10 + -5 t.

Further, the molten iron blended in the step S1 includes the following components by mass percent: c: 4.40% -4.80%, Si: 0.20% -0.50%, Mn: 0.12% -0.18%, P: 0.090% -0.155%, S: 0.001% -0.040%, V: 0.025% -0.065%, Ti: 0.034% -0.118%, and the balance of iron and inevitable impurities.

Further, in step S2, before the gun is opened, 90% +/-5% of the sintered ore is added in a continuous feeding mode with a vibration frequency of 40Hz-50Hz, bottom blowing strong stirring is carried out, and the flow rate of bottom blowing nitrogen is 1980 + -100 m³And/h, and the furnace was shaken in the order of 0 ° → 50 ° ± 10 ° → 330 ° ± 10 ° → 0 °. Part of sinter is added before blowing, iron is reduced after the sinter is melted, and heat is absorbed in the process, so that the function of regulating the temperature of a molten pool can be achieved; the sintered ore enters the converter from normal temperature, and has a certain cooling function of a coolant relative to the temperature of molten iron; meanwhile, the added sintering ore can be used as an oxidant, and can react with silicon, carbon and the like in molten iron in advance through bottom blowing strong stirring matching.

Further, the batch charging process in step S3 is as follows: under oxygen supply of 200m³-500m³Adding a first batch: 80% +/-5% lime, 80% +/-5% raw dolomite, oxygen supply 2500m³-2800m³A second batch was added: 20% +/-5% lime and 20% +/-5% raw dolomite; the rest 10% +/-5% of the sinter ore is supplied with oxygen to 6000m³The mixture is continuously fed into the furnace in a vibration frequency of 25Hz-30 Hz.

Furthermore, the control process of the lance position of the oxygen lance in the step S3 is as follows: oxygen supply 0m³-6000m³When the oxygen lance position is 1.90 +/-0.05 m, oxygen is supplied at 6000m³When the measurement of the TSC of the sublance is finished, the lance position of the oxygen lance is 2.10 +/-0.15 m, and the lance position of the oxygen lance at the end of the measurement of the TSC of the sublance and the smelting is 1.80 +/-0.05 m.

Furthermore, the control process of the oxygen lance flow rate in the step S3 is as follows: oxygen supply 0m³-3000m³While, the oxygen lance flow rate is 58000 +/-1000 m³H, oxygen supply 3000m³-6000m³Time, oxygen lance flow rate is 56000 +/-1000 m³H, oxygen supply 6000m³500m before measuring the TSC of the sublance³While, the oxygen lance flow rate is 63000 +/-500 m³H, 500m before measuring the TSC of the sublance³After the TSC measurement of the sublance, the oxygen lance oxygen supply flow rate is 35000 +/-500 m³H, oxygen supply flow of oxygen lance at smelting end point of 63000 +/-500 m after TSC measurement of sublance³/h。

Further, the oxygen lance injection is performed in step S3Bottom blowing is carried out, and the flow rate of the bottom blowing is controlled as follows: oxygen supply of 0-3000m³While, the flow rate of bottom-blown nitrogen is 1188 +/-100 m³H, oxygen supply 3000m³End of measurement of the sublance TSC with a bottom-blowing argon flow of 594. + -.50 m³The flow rate of bottom blowing argon at the end of measuring the TSC of the sublance and the smelting end point is 1980 +/-100 m³/h。

In the present invention, the following reaction process is involved after the addition of the sintered ore to the molten iron,

[Si]+(FeO)＝(SiO₂)+2[Fe]ΔG^Θreaction 1-386769 +202.3T J/mol

[Mn]+(FeO)＝(MnO)+[Fe]ΔG^ΘReaction 2-123307 +56.48T J/mol

[C]+(FeO)＝CO+[Fe]ΔG^ΘReaction 3-98799-90.76T J/mol

From the thermodynamic analysis of the reaction, before smelting of the full molten iron, under the condition that the temperature of the molten iron is generally lower than 1450 ℃, the reaction 1 takes precedence over the reaction 2, namely, silicon in the iron oxide water added into the sinter ore takes precedence over manganese in the iron oxide water, the sinter ore reacts with carbon in the molten iron to generate CO gas, if the sinter ore and the carbon in the molten iron have local unbalanced reaction, the sputtering is easily caused, and the unbalanced reaction can be effectively solved through the addition control of the sinter ore and the strong bottom blowing stirring; in addition, the reaction between the sinter and the silicon in the molten iron is carried out, the condition that the low alkalinity reaches 1470 ℃ is avoided in advance, partial CO is generated and released in advance, and the concentrated outburst and overflow splashing during smelting for 3-5min is further avoided.

3. Advantageous effects

Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects:

(1) the method for controlling splashing in the smelting of the full molten iron can improve carbon-oxygen imbalance reaction, effectively inhibit splashing during the smelting of the full molten iron, avoid environmental protection events, reduce iron-steel ratio and iron-steel material consumption, improve production technical indexes, can be used according to a uniform standard solidification operation mode, and is suitable for popularization and application.

Detailed Description

The present invention will be described in detail for further understanding of the present invention.

The present invention will be further described with reference to the following examples.

Example 1

The method for controlling splashing in the total molten iron smelting of the embodiment adopts a 300t converter and comprises the following steps:

s1, after steel is discharged from the last furnace, slag is turned over, the amount of remaining slag is controlled to be 10t, and slag splashing is carried out for furnace protection; adding 320.7t of molten iron, wherein the molten iron comprises the following components: c: 4.40%, Si: 0.32%, Mn: 0.12%, P: 0.111%, S: 0.022%, V: 0.048%, Ti: 0.118 percent, and the balance of iron and inevitable impurities, wherein the temperature of molten iron is 1351 ℃; calculating the corresponding lime addition 11612kg, raw dolomite addition 6699kg and sinter addition 15141kg according to the amount of the charged iron water;

s2, before blowing, adding 90% of sinter ore in a continuous feeding mode with a vibration frequency of 45Hz, and carrying out bottom blowing strong stirring with a bottom blowing nitrogen flow of 1980m³Once in a 0 ° → 50 ° → 330 ° → 0 ° oven;

s3, starting smelting by discharging a lance, and supplying oxygen for 200m³-500m³Adding a first batch: 80% lime, 80% raw dolomite, oxygen supply 2500m³-2800m³A second batch was added: 20% lime and 20% raw dolomite; the rest 10 percent of the sinter is supplied with oxygen of 6000m³The mixture is continuously fed into the furnace in a vibration frequency of 25 Hz.

Oxygen lance position: oxygen supply 0m³-6000m³The oxygen lance position is 1.90m, oxygen supply is 6000m³And after the measurement of the TSC of the sublance is finished, the lance position of the oxygen lance is 2.10m, and the lance position of the oxygen lance at the end of the measurement of the TSC of the sublance and the smelting is 1.80 m.

Oxygen lance flow rate: oxygen supply 0m³-3000m³Oxygen lance flow rate of 59000m³H; oxygen supply 3000m³-6000m³Oxygen lance flow rate 56000m³H; oxygen supply 6000m³500m before measuring the TSC of the sublance³Oxygen lance flow of 63500m³H; 500m before measuring TSC of sublance³-the TSC of the sublance is measured, and the oxygen lance oxygen supply flow is 35500m³H; the TSC measurement of the sublance is finished and the smelting end point is finished, and the oxygen supply flow of the oxygen lance is 63500m³/h。

Bottom blowing flow rate: oxygen supply of 0-3000m³The flow rate of bottom-blown nitrogen was 1188m³H, oxygen supply 3000m³End of measurement of the TSC sublance with a bottom-blown argon flow of 594m³The flow rate of bottom-blown argon at the end of measurement of the sublance TSC and the end of smelting is 1980m³And h, the smelting process is stable without splashing, and the steel tapping amount is 315 t.

Example 2

The method for controlling splashing in the total molten iron smelting of the embodiment adopts a 300t converter and comprises the following steps:

s1, discharging steel in the last furnace, controlling the slag turning and remaining amount to be 12t, and splashing slag to protect the furnace; adding 323.6t of molten iron, wherein the molten iron comprises the following components: c: 4.64%, Si: 0.26%, Mn: 0.15%, P: 0.126%, S: 0.002%, V: 0.065%, Ti: 0.064 percent of iron and inevitable impurities as the rest, and the temperature of molten iron is 1321 ℃; calculating the addition amount of 10648kg of lime, 4696kg of raw dolomite and 9502kg of sinter;

s2, before blowing, adding 95% of sinter ore in a continuous feeding mode with a vibration frequency of 50Hz, and carrying out bottom blowing strong stirring with a flow of nitrogen gas of 1880m³And was shaken once per 0 ° → 60 ° → 340 ° → 0 °;

s3, starting smelting by discharging a lance, and supplying oxygen for 200m³-500m³Adding a first batch: 85% lime, 85% raw dolomite, oxygen supply 2500m³-2800m³A second batch was added: 15% lime and 15% raw dolomite; the rest 5 percent of the sinter ore is supplied with oxygen of 6000m³The mixture is continuously fed into the furnace in a vibration frequency of 30 Hz.

Oxygen lance position: oxygen supply 0m³-6000m³The oxygen lance position is 1.95m, oxygen supply is 6000m³And after the measurement of the TSC of the sublance is finished, the oxygen lance position is 2.25m, and the oxygen lance position of the sublance TSC after the measurement is finished and the smelting end point is 1.85 m.

Oxygen lance flow rate: oxygen supply 0m³-3000m³Oxygen lance flow rate of 57000m³H; oxygen supply 3000m³-6000m³Oxygen lance flow rate 56500m³H; oxygen supply 6000m³500m before measuring the TSC of the sublance³Oxygen lance flow 62500m³H; sublance TSC500m before measurement³Oxygen lance oxygen flow 34500m after TSC measurement of sublance³H; the TSC of the sublance is measured and the smelting end point is reached, and the oxygen supply flow of the oxygen lance is 62500m³/h。

Bottom blowing flow rate: oxygen supply of 0-3000m³The flow rate of bottom-blown nitrogen is 1288m³H, oxygen supply 3000m³End of measurement of the TSC sublance with a bottom-blown argon flow of 644m³The flow of bottom-blown argon gas at the end of measuring the sublance TSC and the smelting end point is 2080m³And h, the smelting process is stable and has no splashing, and the steel tapping amount is 312.8 t.

Example 3

The method for controlling splashing in the total molten iron smelting of the embodiment adopts a 300t converter and comprises the following steps:

s1, discharging steel in the last furnace, controlling the slag turning and remaining amount to be 5t, and splashing slag to protect the furnace; 319.1t of molten iron, and the components of the molten iron are as follows: c: 4.78%, Si: 0.50%, Mn: 0.14%, P: 0.090%, S: 0.001%, V: 0.025%, Ti: 0.067 percent, and the balance of iron and inevitable impurities, wherein the temperature of molten iron is 1342 ℃; calculating the lime addition amount of 9728kg, the raw dolomite addition amount of 7816kg and the sinter addition amount of 13000 kg;

s2, before the lower gun is opened, adding 85 percent of sinter ore in a continuous feeding mode with the vibration frequency of 40Hz, carrying out bottom blowing strong stirring, wherein the flow rate of nitrogen gas of bottom blowing is 2080m³Once in a rocking oven at 0 ° → 40 ° → 320 ° → 0 °;

s3, starting smelting by discharging a lance, and supplying oxygen for 200m³-500m³Adding a first batch: 75% lime, 75% raw dolomite, oxygen supply 2500m³-2800m³A second batch was added: 25% lime, 25% raw dolomite; the rest 15 percent of the sinter ore is supplied with oxygen of 6000m³The mixture is continuously fed into the furnace in a vibration frequency of 30 Hz.

Oxygen lance position: oxygen supply 0m³-6000m³The oxygen lance position is 1.85m, oxygen supply is 6000m³And after the measurement of the TSC of the sublance is finished, the oxygen lance position is 1.95m, and the oxygen lance position of the sublance TSC after the measurement is finished and the smelting end point is 1.80 m.

Oxygen lance flow rate: oxygen supply 0m³-3000m³Oxygen lance flow rate 58500m³H; oxygen supply 3000m³-6000m³Oxygen lance flow rate 55000m³H; oxygen supply 6000m³500m before measuring the TSC of the sublance³Oxygen lance flow 63000m³H; 500m before measuring TSC of sublance³Oxygen lance oxygen supply flow 34800m after the measurement of the sublance TSC³H; the TSC measurement of the sublance is finished and the smelting end point is finished, and the oxygen supply flow of the oxygen lance is 63400m³/h。

Bottom blowing flow rate: oxygen supply of 0-3000m³The flow rate of bottom-blown nitrogen is 1088m³H, oxygen supply 3000m³End of measurement of the TSC sublance with a bottom-blown argon flow of 544m³The flow rate of bottom-blown argon at the end of measuring the sublance TSC and the smelting end point is 1880m³And h, the smelting process is stable without splashing, and the steel tapping amount is 307.2 t.

Example 4

The method for controlling splashing in the total molten iron smelting of the embodiment adopts a 300t converter and comprises the following steps:

s1, discharging steel in the last furnace, controlling the slag turning and remaining amount to be 15t, and splashing slag to protect the furnace; adding 305t of molten iron, and mixing the following components: c: 4.5%, Si: 0.20%, Mn: 0.18%, P: 0.155%, S: 0.04%, V: 0.05%, Ti:0.034 percent, the balance of iron and inevitable impurities, and the temperature of molten iron is 1298 ℃; calculating the addition amount of 11227kg of lime, 4615kg of raw dolomite and 1580kg of sinter;

s2, before blowing, adding 95% of sinter ore in a continuous feeding mode with a vibration frequency of 50Hz, and carrying out bottom blowing strong stirring, wherein the flow rate of bottom blowing nitrogen is 1930m³Once in a 0 ° → 50 ° → 330 ° → 0 ° oven;

s3, starting smelting by discharging a lance, and supplying oxygen for 200m³-500m³Adding a first batch: 80% lime, 80% raw dolomite, oxygen supply 2500m³-2800m³A second batch was added: 20% lime and 20% raw dolomite; the rest 5 percent of the sinter ore is supplied with oxygen of 6000m³The mixture is continuously fed into the furnace in a vibration frequency of 25 Hz.

Oxygen lance position: oxygen supply 0m³-6000m³The oxygen lance position is 1.95m, oxygen supply is 6000m³The lance position of the oxygen lance is 2.15m after the TSC measurement of the sublance is finished, and the lance position of the oxygen lance at the end of the TSC measurement of the sublance and the smelting is1.75m。

Oxygen lance flow rate: oxygen supply 0m³-3000m³Oxygen lance flow rate 57900m³H; oxygen supply 3000m³-6000m³Oxygen lance flow rate of 57000m³H; oxygen supply 6000m³500m before measuring the TSC of the sublance³Oxygen lance flow of 63500m³H; 500m before measuring TSC of sublance³After the TSC measurement of the sublance, the oxygen lance oxygen supply flow rate is 35000m³H; the TSC of the sublance is measured and the smelting end point is reached, and the oxygen supply flow of the oxygen lance is 63000m³/h。

Bottom blowing flow rate: oxygen supply of 0-33000m³The flow rate of bottom-blown nitrogen was 1138m³H, oxygen supply 3000m³End of measurement of the TSC sublance with a bottom-blown argon flow of 614m³H, the bottom argon blowing flow at the end of measuring the sublance TSC and the smelting end point is 2000m³And h, the smelting process is stable and has no splashing, and the steel tapping amount is 287.7 t.

The present invention and its embodiments have been described above schematically, but the description is not limited to the embodiments of the present invention, and the present invention is not limited to these embodiments. Therefore, if the person skilled in the art receives the teaching, it is within the scope of the present invention to design the similar manner and embodiments without departing from the spirit of the invention.