A method for smelting cast residue

Abstract

The present application relates to a kind of methods for smelting of casting residue, comprising S1, casting residue recovery;S2, smelting of casting residue;S3, converter slagging control;S4, converter gun position control;S5, converter endpoint control.The present application realizes converter smelting casting residue by casting residue recovery, smelting of casting residue, converter slagging control, gun position control, endpoint control, etc., achieves the purpose of normal smelting, temperature qualified, composition qualified, and thus realizes the stable control of converter smelting smelting of casting residue.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steel metallurgy, and particularly relates to a method for smelting cast residue. BACKGROUND

[0002] In actual production of a steel mill, cast residue is slag in a molten steel ladle after continuous casting is completed. Sometimes, a molten steel ladle pouring worker does not confirm the end state of molten steel ladle pouring, and a part of molten steel is left in the molten steel ladle with slag, resulting in molten steel loss and seriously affecting steel material consumption. In order to reduce this economic loss, it is necessary to recycle and utilize cast residue. There are many difficulties in recycling cast residue, smelting cast residue, and converter smelting, and it is very difficult to smelt cast residue in a converter.

[0003] At present, in domestic public data, there is a processing method for foaming in the recycling process of cast residue, but these methods only explain the recycling method of cast residue, and do not discuss the processing method of cast residue in a converter. When cast residue is smelted in a converter, slag is active, and large spouting phenomenon easily occurs, and metal yield is very low, which also aggravates erosion of the furnace lining. SUMMARY

[0004] In view of the above problems, the purpose of the present application is to provide a method for smelting cast residue, which realizes stable control of smelting cast residue in a converter by recycling cast residue, smelting cast residue, converter slag making control, gun position control, end point control, and the like, so as to realize normal smelting, qualified temperature, and qualified composition of the converter.

[0005] The technical scheme adopted by the present application is as follows:

[0006] The method for smelting cast residue provided by the present application comprises the following steps:

[0007] S1, recycling cast residue; molten iron ladle is used to recycle cast residue, and after recycling is completed, the molten iron ladle is placed in a reverse pouring room for iron folding;

[0008] S2, smelting cast residue; a converter is used to pour cast residue ladle, and the loading amount is controlled according to the molten iron amount converted from the recycling amount of cast residue; during loading, scrap steel is added first, and then molten iron is poured; front and rear furnace swing operations are performed during pouring of molten iron, and cast residue and molten iron are uniformly mixed;

[0009] S3, converter slag making control; cast residue ladle is poured into a converter, and a double slag method is used for operation of the converter; according to different recycling amounts of cast residue, the slag material into the converter is appropriately reduced during smelting operation of the converter;

[0010] S4, converter gun position control; a low gun position is used first, and then a high gun position is used before double slag, a high gun position is used after double slag, and a conventional control model is used after stabilization;

[0011] S5, converter end point control; according to the steelmaking automation calculation, combined with the flame at the furnace mouth, TSC is measured using the sublance, after blowing to the target composition and target temperature of the molten steel, the lance is lifted according to the measurement result of TSC, and the molten steel is quickly tapped according to the result of the molten steel rapid analyzer.

[0012] Further, the step S1 specifically comprises: recovering the casting residue by using the hot metal ladle, the hot metal ladle must have molten iron covering the bottom, and the amount of molten iron is required to be 30t-80t; placing the prepared hot metal ladle on the overpass trolley, opening to the ladle dumping, lifting the hot metal ladle to the ladle dumping position by the crown block, after the recovery of the casting residue is completed, lifting the hot metal ladle to the overpass trolley, opening to the converter dumping, and then lifting the hot metal ladle to the ladle dumping interval for iron folding.

[0013] Further, the hot metal ladle recovering the casting residue must be a ladle number with good static tapping or top slag modification, and the process from recovering the casting residue from the hot metal ladle to returning the hot metal ladle to the ladle dumping interval for iron folding is controlled within 0.5-2 hours, and the maximum number of recovered ladles is 6.

[0014] Further, the iron folding process specifically comprises: first checking whether the slag surface of the hot metal ladle is crusty when the hot metal ladle is returned, if the hot metal ladle is crusty, the iron folding can be carried out after treatment; paying attention to the change of the slag surface during the iron folding, stopping the iron folding when the weight reaches 50% of the planned weight, checking the slag surface of the hot metal ladle, confirming that there is no abnormality, and then carrying out the next iron folding, stopping again when the weight reaches 90% of the planned weight, folding the remaining molten iron after confirming the state of the hot metal ladle and no abnormality; after recovering the casting residue from the hot metal ladle, no desulfurization treatment and slag removal treatment is carried out in the next two furnaces, and the hot metal ladle recovering the casting residue can only be given a LF straight-up steel grade in the next two furnaces.

[0015] Further, the step S2 specifically comprises: the converter is charged with the casting residue ladle number, and the charging amount is controlled according to the amount of molten iron calculated from the amount of recovered casting residue; after recovering the casting residue, the iron is folded, charged into the converter, and the weight is 20t-25t, if the weight is too large, it means that there is more remaining steel in the continuous casting machine, and the molten iron calculation method is:

[0016] Casting residue recovery amount: <20t, molten iron calculation amount: consider 50% recovery rate, i.e. actual amount*0.5; casting residue recovery amount: 20-25t, molten iron calculation amount: consider 60% recovery rate, i.e. actual amount*0.6; casting residue recovery amount: >25t, molten iron calculation amount: 25*0.6+(actual amount-25);

[0017] During the charging process of the converter, scrap steel must be added first, and then molten iron is charged; since the hot metal ladle contains casting residue, small flow of molten iron is charged, after charging 80t-100t, the converter is rocked front and back, after there is no abnormal reaction, the remaining molten iron is charged; after the molten iron is charged, the converter is rocked front and back twice, and the lance can be lowered to blow oxygen after there is no violent reaction.

[0018] Further, the step S3 specifically comprises: entering into the casting residue furnace, the converter adopts double slag method operation, according to the different casting residue recovery amount, the converter smelting operation, should appropriately reduce the slag material into the furnace, specifically as follows:

[0019] The casting residue recovery amount is less than 20t, the converter lime reduction amount is 1000kg; the casting residue recovery amount is 20-25t, the converter lime reduction amount is 1500kg; the casting residue recovery amount is more than 25t, the converter lime reduction amount is 2000kg;

[0020] Slag material adding control: the slag material mainly supplements CaO, MgO and slag amount, the added slag material includes active lime, light-burned dolomite and iron ore, and the specific method is as follows:

[0021] Slag material control before slagging: the active lime adding amount is 10±0.5kg / t; the light-burned dolomite adding amount is 15±0.5kg / t; the adding is carried out after 30-40s of blowing;

[0022] Slag material control after slagging: the casting residue recovery amount is less than 20t, the converter lime reduction amount is 21±0.5kg / t; the casting residue recovery amount is 20-25t, the converter lime reduction amount is 19±0.5kg / t; the casting residue recovery amount is more than 25t, the converter lime reduction amount is 17±0.5kg / t; the light-burned dolomite adding amount is 5±0.5kg / t; the adding is carried out after the ignition of the lower gun after slagging; the iron ore is added according to the temperature after the stable furnace slag.

[0023] Further, the step S4 specifically comprises:

[0024] Blowing gun position: 2900mm-3000mm; blowing oxygen pressure: 1.0Mpa-1.15Mpa; oxygen flow rate: 54000-56000Nm 3 / h; the blowing gun position is lowered to 2400-2450mm after blowing for 60-70s, the blowing gun position is lowered to 2150-2200mm after blowing for 130-140s, the blowing gun position is lifted to 2600-2650mm after blowing for 200-210s, the blowing gun position is lifted to 3200-3250mm after blowing for 250-260s, and the gun position is waiting according to the furnace slag, and the gun is lifted and slag is discharged;

[0025] After slagging, reblowing is carried out, the blowing gun position is 3000-3050mm, and the oxygen flow rate is 45000-46000Nm 3 / h; after the ignition is successful, the gun position is lowered to 2700-2800mm, the oxygen flow rate is adjusted to 55000-55500Nm 3 / h.

[0026] Compared with the prior art, the application has the following beneficial effects:

[0027] 1. Reduce the problem of molten steel loss caused by remaining steel during continuous casting process, reduce the consumption of steel material, and effectively improve the yield of molten steel;

[0028] 2. Fill the gap of converter casting slag recycling method;

[0029] 3. Optimize the casting slag recycling process and reduce the safety risk in the process;

[0030] 4. Reduce the flux consumption and reduce the cost of steelmaking process. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 A flowchart of a method for recycling and smelting casting slag according to the present application. DETAILED DESCRIPTION

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0033] Referring to the accompanying Figure 1 The method for recycling and smelting casting slag according to the present application specifically comprises the following steps:

[0034] S1, recycling of casting slag;

[0035] Generally, the casting slag is recycled by using a hot metal ladle. The hot metal ladle must have molten iron covering the bottom of the ladle, and the amount of molten iron required is 30t-80t. The prepared hot metal ladle is placed on the overpass trolley, and the ladle is opened to the dumping position. The hot metal ladle is lifted to the dumping position by the overhead crane. After the recycling of the casting slag is completed, the hot metal ladle is lifted to the overpass trolley, and the ladle is opened to the converter position. Then the hot metal ladle is lifted to the dumping interval and the iron is folded.

[0036] Requirements for recycling of casting slag:

[0037] The hot metal ladle for recycling of casting slag must be a ladle with good modification of the top slag after calm steel tapping. The ladle with boiling steel treated by LF cannot recycle the casting slag, in order to prevent the top slag from being easily oxidized and causing spatter during recycling.

[0038] The number of ladles for recycling of casting slag and the recycling time are strictly controlled. From the start of recycling of casting slag from the hot metal ladle to the folding of iron in the dumping interval, the control time is within 2 hours, and the number of recycled ladles is at most 6, in order to avoid causing the hot metal ladle to condense and form a shell or causing serious slag running during the converter blowing process.

[0039] Folding of iron after recycling:

[0040] The ladle is returned first to check the slag surface of the ladle, if the ladle is caked, it can be folded after treatment. When folding, pay attention to the change of the slag surface, when the weight of the folded iron reaches 50% of the planned weight, stop folding, check the slag surface of the ladle, confirm that there is no abnormality, then proceed to the next step of folding, when the weight of the folded iron reaches 90% of the planned weight, stop again, confirm the state of the ladle, and fold the remaining molten iron after confirming that there is no abnormality.

[0041] After the ladle recovers the casting slag, the two furnaces do not perform desulfurization treatment and slagging treatment, and the two furnaces can only produce LF steel grade after the ladle recovers the casting slag.

[0042] S2, smelting of casting slag;

[0043] Converter charging system and charging method:

[0044] The ladle is returned first to check the slag surface of the ladle, if the ladle is caked, it can be folded after treatment. When folding, pay attention to the change of the slag surface, when the weight of the folded iron reaches 50% of the planned weight, stop folding, check the slag surface of the ladle, confirm that there is no abnormality, then proceed to the next step of folding, when the weight of the folded iron reaches 90% of the planned weight, stop again, confirm the state of the ladle, and fold the remaining molten iron after confirming that there is no abnormality.

[0045] Casting slag recovery: <20t, molten iron conversion: consider 50% recovery rate, i.e. actual amount * 0.5; Casting slag recovery: 20-25t, molten iron conversion: consider 60% recovery rate, i.e. actual amount * 0.6; Casting slag recovery: >25t, molten iron conversion: 25*0.6+(actual amount-25).

[0046] Charging method: during the charging of the converter, scrap steel must be added first and then molten iron is added. Since the ladle contains casting slag, small flow of molten iron must be added, after 80-100t is added, the converter is shaken front and back, after no abnormal reaction, the remaining molten iron is added. After the molten iron is added, the converter is shaken front and back twice, after no violent reaction, the lance can be lowered to blow oxygen.

[0047] S3, converter slag control;

[0048] When the casting slag furnace is added, the converter adopts double slag method operation,

[0049] When the casting slag furnace is added, the converter adopts double slag method operation, to prevent slag from running due to active slag, resulting in environmental accidents. There is a large amount of high-alkali slag in the casting slag, which is beneficial to the smelting of the converter; according to the different recovery amount of the casting slag, the smelting operation of the converter should appropriately reduce the slag material, as follows:

[0050] Casting slag recovery <20t, converter lime reduction 1000kg; Casting slag recovery 20-25t, converter lime reduction 1500kg; Casting slag recovery >25t, converter lime reduction 2000kg;

[0051] Slag material addition control: the slag material mainly supplements CaO, MgO and slag amount, the added slag material includes active lime, light-burned dolomite and iron ore, and the specific method is as follows:

[0052] Slag material control before slagging: the active lime addition amount is 10±0.5 kg / t; the light-burned dolomite addition amount is 15±0.5 kg / t; and the addition is made after 30-40 s of blowing;

[0053] Slag material control after slagging: the casting residue recovery amount is <20 t, the converter lime reduction amount is 21±0.5 kg / t; the casting residue recovery amount is 20-25 t, the converter lime reduction amount is 19±0.5 kg / t; the casting residue recovery amount is >25 t, the converter lime reduction amount is 17±0.5 kg / t; the light-burned dolomite addition amount is 5±0.5 kg / t; the addition is made after the ignition of the lower lance after slagging; and the iron ore is added according to the temperature after the stable furnace slag.

[0054] S4, converter lance position control;

[0055] Blowing lance position: 2900 mm-3000 mm; blowing oxygen pressure: 1.0 Mpa-1.15 Mpa; oxygen flow rate: 54000-56000 Nm 3 / h; after 60-70 s of blowing, the lance position is lowered to 2400-2450 mm, after 130-140 s of blowing, the lance position is lowered to 2150-2200 mm, after 200-210 s of blowing, the lance position is raised to 2600-2650 mm, after 250-260 s of blowing, the lance position is raised to 3200-3250 mm, and the lance position is waited for according to the slag condition, the lance is lifted and slag is discharged;

[0056] After slagging, reblowing is carried out, the blowing lance position is 3000-3050 mm, and the oxygen flow rate is 45000-46000 Nm 3 / h; after the ignition is successful, the lance position is lowered to 2700-2800 mm, and the oxygen flow rate is adjusted to 55000-55500 Nm

[0057] S5, converter end point control;

[0058] According to the automatic calculation of steelmaking, combined with the flame at the furnace mouth, the TSC is measured by using the sub-lance, according to the TSC measurement result, the lance is lifted after the blowing to the target composition and target temperature of the molten steel, and the molten steel is rapidly discharged according to the result of the molten steel rapid analyzer.

[0059] The application is further described below through specific examples:

[0060] Method for reverberatory smelting of casting residue converter, process route: casting residue recovery→casting residue reverberatory smelting→argon station→refining→casting machine, smelting steel QB, ladle D level, turnover time 100 min, casting residue recovery amount 28 t, converter target tapping temperature 1600 DEG C, finished product requirement P≤0.025%; comprising the following steps:

[0061] S1, casting residue recovery method: the prepared 6# ladle, weight 173 tons, containing 43 tons of molten iron, is placed on the cross car, and the ladle is opened to the ladle collapse, the ladle is lifted to the ladle position by the crane, and the time is 1 hour and 50 minutes, 5 ladles of casting residue are recovered, the recovered steel is QB and SPHC, after recovery, the crane weight is 201 tons, the casting residue is 28 tons, after the casting residue recovery is completed, the ladle is lifted to the cross car by the crane, and the ladle is opened to the converter collapse, and then the ladle is lifted to the ladle interval by the crane.

[0062] When the 6# ladle is transferred back, the ladle slag surface has no crust phenomenon, and the ladle is folded in the 2# pit. When folding, pay attention to the change of the slag surface, stop folding when the folding weight reaches 305 tons, check the ladle slag surface, there is no abnormality, proceed to the next folding, stop again when the folding weight reaches the planned weight of 382 tons, continue folding after confirming the ladle state and no abnormality, and the weight of the folded ladle is 395 t.

[0063] S2, casting residue reverberatory smelting:

[0064] Loading system: the converter is loaded with casting residue ladle times, and the loading amount is controlled to be the casting residue recovery amount. The ladle is loaded with 28 tons of casting residue, and the iron water conversion amount is 25*0.6+(28-25)=18 tons.

[0065] Loading method: during the loading of the converter, scrap steel must be added first and then iron water is added. Because the ladle contains casting residue, the iron water must be added in small flow, after 90 tons of iron water is added, the converter is shaken in front and back, and after no abnormal reaction, the remaining iron water is added. After the iron water is added, the converter is shaken in front and back twice, and after no violent reaction, the lance can be lowered to blow oxygen.

[0066] S3, converter slag control:

[0067] The converter adopts double slag method operation when the casting residue is added, which prevents the occurrence of slag running caused by active slag, resulting in environmental protection accidents. There is a large amount of high alkalinity slag in the casting residue, which is beneficial to the converter smelting. According to the different casting residue recovery amount, the slag material into the converter should be appropriately reduced during the converter smelting operation, the casting residue recovery amount is 28 t, and the lime reduction amount of the converter is 2000 kg;

[0068] After the successful oxygen blowing, 2580 kg of active lime and 4010 kg of light-burned dolomite were added in 32 seconds. According to the slag condition, the lance was lifted to discharge the slag. After discharging the slag, the blowing was restarted. After the successful ignition, 4450 kg of active lime and 1310 kg of light-burned dolomite were added.

[0069] S4, control of the lance position of the converter:

[0070] Oxygen blowing was performed with the lance position of 2960 mm and the oxygen pressure of 1.05 MPa. After the successful ignition, the first batch of slag was added in 32 seconds. The lance position was lowered to 2420 mm in 65 seconds, raised to 2155 mm in 134 seconds, raised to 2610 mm in 206 seconds, and raised to 3222 mm in 255 seconds. According to the slag condition, the lance was lifted to discharge the slag. After discharging the slag, the blowing was restarted with the lance position of 3020 mm and the oxygen flow rate of 45050 Nm 3 / h. After the successful ignition, the lance position was raised to 2710 mm, and the oxygen flow rate was adjusted to 55800 Nm 3 / h.

[0071] S5, control of the end point of the converter:

[0072] According to the automatic calculation and the actual situation of the flame, when the oxygen accumulation reached 10886 Nm 3 / h, TSC test was performed through the sub-lance. The TSC measurement result was temperature 1583℃, carbon 0.42%, and 500 kg of ore was added as a cooling material. The blowing was performed for 90 seconds, and the lance was lifted at the end of the blowing. The end point temperature was 1622℃, and the oxygen value was 438 ppm. The rapid analyzer detected the results of C=0.055%, P=0.0163%, Mn=0.08%, and S=0.036%, which met the requirements of the steel grade composition, and the steel was rapidly tapped.

[0073] After the steel was tapped, the LF furnace was entered, and the LF furnace treatment was qualified for casting. The casting machine was normally casted.

[0074] The details of the present application are well known.

[0075] The above-described embodiments are merely preferred embodiments of the present application, and do not limit the scope of the present application. Various modifications and improvements to the technical solutions of the present application made by those skilled in the art without departing from the design spirit of the present application shall fall within the protection scope of the present application.

Claims

1. A method for smelting of a foundry residue, characterized in that, The method comprises the following steps: S1, casting residue recovery; adopt molten iron tank to recover casting residue, after recovery, place the molten iron tank in the reverse pouring room to fold iron; S2, casting residue recycling smelting; the converter is mixed with the casting residue tank, the loading amount is controlled according to the casting residue recovery amount, the folding amount of the molten iron, in the process, the waste steel must be added first, then the molten iron is mixed, and the front and rear shaking furnace operation is carried out during the mixing of the molten iron, and the casting residue and the molten iron are uniformly mixed; S3, converter slag control; the converter adopts double slag method operation, according to the different casting residue recovery amount, the converter smelting operation, the slag material is appropriately reduced; S4, converter gun position control; before double slag, low gun position is used first, then high gun position is used, after double slag, high gun position is used, and then the conventional control model is stabilized; S5, converter end point control; according to the automatic calculation of steelmaking, combined with the flame at the furnace mouth, the TSC is measured by using the sub-gun, according to the TSC measurement result, the lance is lifted after blowing to the target composition and target temperature of the molten steel, and the molten steel is quickly discharged according to the result of the molten steel rapid analyzer; The step S3 specifically comprises the following steps: The casting residue recovery amount is less than 20t, the converter lime reduction amount is 1000kg; the casting residue recovery amount is 20-25t, the converter lime reduction amount is 1500kg; the casting residue recovery amount is greater than 25t, and the converter lime reduction amount is 2000kg; Slag material adding control: the slag material mainly supplements CaO, MgO and slag amount, the added slag material includes active lime, light-burned dolomite and iron ore, and the specific method is as follows: Slag material control before slagging: the active lime adding amount is 10±0.5kg / t; the light-burned dolomite adding amount is 15±0.5kg / t; and the light-burned dolomite is added after 30-40s of blowing; Slag material control after slagging: the casting residue recovery amount is less than 20t, the converter lime reduction amount is 21±0.5kg / t; the casting residue recovery amount is 20-25t, the converter lime reduction amount is 19±0.5kg / t; the casting residue recovery amount is greater than 25t, and the converter lime reduction amount is 17±0.5kg / t; the light-burned dolomite adding amount is 5±0.5kg / t; the light-burned dolomite is added after the gun is ignited after slagging; and the iron ore is added according to the rich temperature after the slag is stable; The step S4 specifically comprises the following steps: Blowing gun position: 2900mm-3000mm; oxygen pressure during blowing: 1.0Mpa-1.15Mpa; oxygen flow during blowing: 54000-56000Nm³ / h; the gun position is lowered to 2400-2450mm after blowing for 60-70s, the gun position is lowered to 2150-2200mm after blowing for 130-140s, the gun position is lifted to 2600-2650mm after blowing for 200-210s, the gun position is lifted to 3200-3250mm after blowing for 250-260s, and the gun position is lifted to 3200-3250mm after blowing for 250-260s; the gun position is waiting according to the slag condition, and the lance is lifted to discharge the slag. After slagging, reblowing, opening blowing lance position: 3000-3050mm, oxygen flow 45000-46000Nm 3 / h; after successful ignition, lance position is lowered to 2700-2800mm, oxygen flow is adjusted to 55000-55500Nm 3 / h.

2. A method of recycling of slag according to claim 1, characterized in that: The step S1 specifically comprises: recovering the casting residue by adopting the hot metal ladle, the hot metal ladle must have molten iron covering the bottom, and the amount of molten iron is required to be 30t-80t; placing the prepared hot metal ladle on the overpass trolley, opening to the ladle dumping, lifting the hot metal ladle to the ladle dumping position by the crown block, waiting for the recovery of the casting residue, lifting the hot metal ladle to the overpass trolley, opening to the converter dumping, and then lifting the hot metal ladle to the ladle dumping interval.

3. A method of smelting of cast slags according to claim 2, characterized in that: The hot metal ladle recovering the casting residue must be the ladle number of the static tapping or the top slag modification, and the process from recovering the casting residue by the hot metal ladle to returning the hot metal ladle to the ladle dumping interval is controlled within 0.5-2 hours, and the number of recovered ladles is at most 6.

4. A method of recycling of slag according to claim 3, characterized in that: The folding iron process specifically comprises: first checking whether the slag surface of the hot metal ladle is crusty when the hot metal ladle is returned, and if the hot metal ladle is crusty, the folding iron can be carried out after treatment; paying attention to the change of the slag surface when folding iron, stopping folding iron when the weight reaches 50% of the planned weight, checking the slag surface of the hot metal ladle, confirming that there is no abnormality, and then folding the remaining molten iron after the next folding iron weight reaches 90% of the planned weight.

5. A method of smelting of cast slags according to claim 4, characterized in that: The two furnaces after recovering the casting residue by the hot metal ladle do not carry out desulfurization treatment and slagging treatment, and the two furnaces after recovering the casting residue by the hot metal ladle can only give the LF straight steel grade. The step S2 specifically comprises: the ladle number of the converter is filled with the casting residue, and the filling amount is controlled according to the molten iron amount converted by the casting residue recovery amount; folding iron after recovering the casting residue, filling into the converter, and the weight is 20t-25t, if the weight is too large, it means that there is more steel left in the continuous casting machine, and the molten iron conversion method: Casting residue recovery amount: <20t, molten iron conversion amount: considering 50% recovery rate, i.e. actual amount*0.5; casting residue recovery amount: 20-25t, molten iron conversion amount: considering 60% recovery rate, i.e. actual amount*0.6; casting residue recovery amount: >25t, molten iron conversion amount: 25*0.6+(actual amount-25); During the filling process of the converter, scrap steel must be added first, and then molten iron is added; because the hot metal ladle contains casting residue, small flow of molten iron is added, 80t-100t is added, the converter is shaken front and back, after no abnormal reaction, the remaining molten iron is added; after the molten iron is added, the converter is shaken front and back twice, after no violent reaction, the lance can be lowered to blow oxygen.

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