CN108977614B - Method for inhibiting splashing in earlier stage of converter smelting - Google Patents

Method for inhibiting splashing in earlier stage of converter smelting Download PDF

Info

Publication number
CN108977614B
CN108977614B CN201810915920.4A CN201810915920A CN108977614B CN 108977614 B CN108977614 B CN 108977614B CN 201810915920 A CN201810915920 A CN 201810915920A CN 108977614 B CN108977614 B CN 108977614B
Authority
CN
China
Prior art keywords
oxygen
smelting
lance
oxygen pressure
splashing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810915920.4A
Other languages
Chinese (zh)
Other versions
CN108977614A (en
Inventor
高志滨
薛志
段朋朋
刘忠建
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shandong Iron and Steel Co Ltd
Original Assignee
Shandong Iron and Steel Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shandong Iron and Steel Co Ltd filed Critical Shandong Iron and Steel Co Ltd
Priority to CN201810915920.4A priority Critical patent/CN108977614B/en
Publication of CN108977614A publication Critical patent/CN108977614A/en
Application granted granted Critical
Publication of CN108977614B publication Critical patent/CN108977614B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/30—Regulating or controlling the blowing
    • C21C5/35—Blowing from above and through the bath
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/40—Production or processing of lime, e.g. limestone regeneration of lime in pulp and sugar mills

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)

Abstract

The invention belongs to the field of converter steelmaking, and particularly relates to a method for inhibiting splashing in the early stage of converter smelting, which comprises the following steps: 1) after the smelting furnace starts, the oxygen lance is lowered into the furnace and oxygen is blown, the whole lance position is blown within 3-4 minutes according to the trend of high-low, the lance position is lowered from 1800 minus 1900mm to 1550 minus 1650mm of the normal smelting lance position, and simultaneously, the oxygen pressure is raised to 0.85-0.88 MPa; 2) blowing for 4 min 10 s to 4 min 30 s, and starting to carry out operation change including gun lifting; adding materials; reducing the pressure; 3) after the step 2) is finished, improving the bottom blowing flow; 4) after all the operations are finished, gradually reducing the lance position, increasing the oxygen pressure, recovering the bottom blowing flow, adjusting the oxygen pressure to the level before the operation change in the step 2), and then starting smelting. The invention ensures the stability of the reaction in the molten pool in the earlier stage of converter smelting and avoids the problems of splashing, especially smoke-producing splashing with iron, caused by over-sufficient metallurgical power or rapid temperature rise in the molten pool in the earlier stage of blowing.

Description

Method for inhibiting splashing in earlier stage of converter smelting
Technical Field
The invention belongs to the field of converter steelmaking, and particularly relates to a method for inhibiting splashing in the early stage of converter smelting.
Background
The converter splash is an important reason for metal loss in the steel-making link. After preliminary slagging in the early stage of smelting begins, molten metal contains a large amount of gas generated by reaction in a furnace, meanwhile, the interface of slag and the molten metal is not clear, and the slag is mixed with a large amount of metal, so that if splashing occurs in the reaction process in the furnace, a large amount of iron-containing slag is sprayed out of the furnace, and metal loss is caused. The temperature of the molten pool rises unevenly in the early stage of smelting, and the existing low-temperature dead angle can also cause early splashing in the process of colliding with a high-temperature area. In order to solve the problem of frequent splashing in the early stage of smelting, a novel operation method needs to be adopted to replace the conventional smelting process and prevent the splashing in the early stage.
Disclosure of Invention
In order to solve the above problems, an object of the present invention is to provide a method for suppressing the splashing in the early stage of converter smelting. The invention provides a control method for inhibiting splashing in the early stage of smelting by researching the change characteristics of the reaction in the converter within 4-5 minutes of converter blowing, which ensures the normal and stable reaction in the converter in the early stage of blowing and avoids the splashing problem, particularly the splashing with iron, caused by violent reaction in the converter in the early stage or uneven temperature change.
The specific technical scheme of the invention is as follows:
the invention provides a control method for inhibiting splashing in the early stage of converter smelting, which comprises the following steps:
1) after the smelting furnace starts, the oxygen lance is lowered into the furnace and oxygen is blown, the whole lance position is blown within 3-4 minutes according to the trend of high-low, the lance position is lowered from 1800 minus 1900mm to 1550 minus 1650mm, and simultaneously, the oxygen pressure is raised to 0.85-0.88 MPa;
2) when the blowing time is from 4 minutes 10 seconds to 4 minutes 30 seconds, the operation change is started, and the operation change mainly comprises the following steps:
① lifting the lance, wherein the lance position is increased by 200-;
② feeding, namely adding lime or raw dolomite into the furnace from a storage bin in 2-3 batches to press slag rising at the early stage and then rising to a furnace opening;
③, pressure reduction, namely instantly reducing the oxygen pressure after the lance is lifted for feeding, further relieving the intensity of the reaction in the furnace, reducing the stirring power brought to the molten pool by top blowing oxygen and promoting the steel slag in the furnace to recover to a calm state.
3) After the step 2) is finished, a specially set bottom blowing strong stirring control switch is selected to improve the bottom blowing flow, increase the stirring power from bottom blowing gas and promote CO and CO generated by reaction in molten steel2And the gas is overflowed to consolidate the operation effect.
4) After all the operations are finished, the early-stage splashing is effectively inhibited, the lance position is gradually reduced, the oxygen pressure is increased, the bottom blowing flow is recovered, the bottom blowing flow is adjusted to the original normal level (the level before the operation change in the step 2), and then the smelting is started. Starting the conventional smelting operation.
Preferably, the lance position in the step 1) is at a basic interval of 45-50mm according to a high-low trend, and oxygen is blown at a distance of 200-300m3Time 20-30 second is the basic time interval, and the gun position gradually decreases in amplitude and decreases in frequency.
Preferably, the first batch of lime, dolomite and ore are normally added according to the existing model in the step 1), the addition amount depends on the silicon content of molten iron, the addition amount of slag is 55-60%, the addition amount of ore is 25-30%, and the balance is dolomite.
Preferably, the lance position and the oxygen pressure of the oxygen lance in the step 1) need to reach the normal level completely before smelting for 4 minutes, so that the subsequent operation effect is prevented from being influenced because one oxygen lance cannot reach the normal level.
Preferably, the lance position lifting in the step 2) must be controlled between 200-300mm, so as to avoid the slag TFe from being raised due to excessive lifting; the feeding amount of lime or raw dolomite is controlled to be 500kg per batch of 300-; the oxygen pressure needs to be instantly reduced to 0.65-0.75 MPa.
Preferably, the bottom-blowing flow rate in step 3) needs to be set at 600-800Nm3Is between/h.
Preferably, in the step 4), after the splashing is effectively controlled, the gun position is gradually reduced, the oxygen pressure is recovered, the bottom blowing flow is recovered, the time for adjusting to the original normal level is controlled between 20 and 30 seconds, and the influence on the operation effect caused by too fast recovery is avoided.
Preferably, the adjustment to the original normal level in the step 4) comprises reducing the lance position to 1550-3/h。
In the existing operation process, several operations such as constant gun pressure, variable gun pressure, constant gun pressure and the like are mostly used, namely, the oxygen pressure at the gun position is not moved in the whole process, the oxygen pressure at the gun position is moved, the oxygen pressure at the gun position is not moved, and the like. None of these operations is effective in stably controlling the splashing of the converter. This operation has combined three kinds of modes in an organic whole in fact, after rifle position is pressed down gradually to normal rifle position, reaches the key time point of silicomanganese oxidation, becomes rifle position, becomes oxygen pressure operation, and the cooperation is added with the material, bottom blowing stirs by force, can make the smelting process more stable, after the suppression splash takes place, successively resumes rifle position, oxygen pressure, reinforced, bottom blowing, the back is operated according to reinforced model to being close the terminal point. The core of the method is the series combination of gun position lifting, oxygen pressure reduction, feeding pressing and bottom blowing strong stirring before splashing occurs.
Compared with the prior art, the invention has the advantages that:
(1) the problem of unstable splashing control caused by no matching of gun position, oxygen pressure and charging or incorrect matching sequence in conventional operation is solved by the gun lifting-charging-pressure reducing operation steps in the earlier stage of smelting, the intensity of reaction change in the furnace is quickly relieved, the soft blowing atmosphere in the furnace under high gun position and low oxygen pressure is formed, and the phenomenon of slag splashing overflow caused by the action of severe external force during the silicon-manganese oxidation period is avoided.
(2) Through the bottom blowing strong stirring effect, the effects of the gun lifting, feeding and pressure reduction operation steps are consolidated, the upward floating of gas in molten steel is promoted, the early-stage temperature is uniform, a good molten steel motion flow field is formed, and the stable control capability is improved.
(3) The invention effectively controls the splashing in the early stage of converter smelting, particularly the splashing with iron, reduces the metal loss, reduces the consumption of steel and iron materials of the converter, and plays an active role in cost reduction and efficiency improvement in the steelmaking process. Meanwhile, due to the effective reduction of the splashing condition, the smoke dust amount generated in the earlier stage of smelting is reduced, the safety of equipment and personnel is guaranteed, and the positive influence is exerted on safety and environment-friendly work.
Detailed Description
The present invention will be further described with reference to the following specific examples.
Example 1
1. Adding scrap steel and molten iron into the converter to prepare for starting the smelting production of the first time. After the equipment has the conditions, the gun is lowered and oxygen is turned on to start blowing. The initial gun position is 1850 mm. And blowing for 1 minute and 30 seconds, and then adding the first batch of slag charge and ore, wherein 3200kg of lime is added, 1100kg of ore is added, and 1500kg of dolomite is added.
2. After blowing is started, when blowing is carried out for 3 minutes, the position of an oxygen lance is reduced to 1550mm, and the oxygen pressure is increased to 0.85-0.88Mpa, namely the normal smelting horizontal state.
3. When the blowing time is 4 minutes and 15 seconds, the gun position is increased by 200mm to 1750mm, the accuracy is ensured in the lifting process, the lifting is strictly carried out according to the range of 200 and 300mm, and the overhigh lifting is avoided; then adding lime into the furnace in 3 batches, wherein each batch is 350kg, and the interval between each batch is about 10 seconds; then quickly reducing the oxygen pressure to 0.68Mpa so as to realize the purpose of quickly slowing down the intensity of the reaction in the furnace.
4. After the gun lifting-charging-pressure reducing operation is completely finished, the specially set auxiliary bottom blowing mode is used for increasing the bottom blowing flow to 600Nm3And h, performing bottom blowing strong stirring for 10 seconds.
5. And (4) the reaction in the furnace returns to be calm, the gun position is gradually reduced to 1550mm, feeding is started according to the model, and meanwhile, the bottom blowing flow is returned to be normal.
Example 2
1. Adding scrap steel and molten iron into the converter to prepare for starting the smelting production of the first time. After the equipment has the conditions, the gun is lowered and oxygen is turned on to start blowing. The initial gun position is 1800mm high. And blowing for 1 minute and 30 seconds, and then adding the first batch of slag charge and ore, wherein 3300kg of lime is added, 1150kg of ore is added, and 1500kg of dolomite is added.
2. After blowing is started, when blowing is carried out for 3 minutes, the position of an oxygen lance is reduced to 1550mm, and the oxygen pressure is increased to 0.85-0.88Mpa, namely the normal smelting horizontal state.
3. When the blowing time is 4 minutes and 15 seconds, the gun position is increased by 200mm to 1750mm, the accuracy is ensured in the lifting process, the lifting is strictly carried out according to the range of 200 and 300mm, and the overhigh lifting is avoided; then adding lime into the furnace in 3 batches, wherein each batch is 350kg, and the interval between each batch is about 10 seconds; then quickly reducing the oxygen pressure to 0.70Mpa so as to realize the purpose of quickly slowing down the intensity of the reaction in the furnace.
4. After the gun lifting-charging-pressure reducing operation is completely finished, the specially set auxiliary bottom blowing mode is used for increasing the bottom blowing flow to 600Nm3And h, performing bottom blowing strong stirring for 10 seconds.
5. And (4) the reaction in the furnace returns to be calm, the gun position is gradually reduced to 1550mm, feeding is started according to the model, and meanwhile, the bottom blowing flow is returned to be normal.
The inventor fully considers the influence of the operation between 4-5 minutes in the earlier stage of the converter smelting on the earlier stage splash suppression effect by combining production practice, and performs a series of operations on a lance position, oxygen pressure, feeding and bottom blowing by changing the original operation steps so as to achieve the optimal control effect.
According to the control method, the process method is adopted, firstly, a furnace smelting is started, the gun position and the oxygen pressure are controlled to be normal, and then the operations of moving the gun, feeding, reducing the pressure and blowing at the bottom are carried out in the severe reaction time period of the silicomanganese oxidation period of 4-5 minutes. The smelting process operators carry out system operation, after the converter is applied, the splashing rate of the converter is reduced to be within 10%, the splashing slag amount is controlled to be within 5.8kg/t, the problem of metal loss caused by splashing is avoided, the loss of the converter cost is reduced, and meanwhile, the method has good effects on environmental protection requirements, the safety of the operators and the stability of equipment.
Unless otherwise specified, all the details in this specification are prior art in this field and are not described herein again.
The present invention may be embodied in many different forms and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (4)

1. A method for inhibiting splashing in the early stage of converter smelting comprises the following steps:
1) after the smelting furnace starts, the oxygen lance is lowered into the furnace and oxygen is blown, the whole lance position is blown within 3-4 minutes according to the trend of high-low, the lance position is lowered from 1800 minus 1900mm to 1550 minus 1650mm, and simultaneously, the oxygen pressure is raised to 0.85-0.88 MPa;
2) and when the blowing time is from 4 minutes 10 seconds to 4 minutes 30 seconds, starting to carry out operation change, wherein the method comprises the following steps:
① lifting the lance, wherein the lance position is increased by 200-;
② feeding, namely feeding lime or raw dolomite into the furnace from a storage bin in 2-3 batches;
③ decompression, after gun lifting feeding, the oxygen pressure is reduced;
3) after the step 2) is finished, the bottom blowing flow is increased to 600-800Nm3/h；
4) After all the operations are finished, gradually reducing the lance position, increasing the oxygen pressure, recovering the bottom blowing flow, adjusting the oxygen pressure to the level before the operation change in the step 2), and then starting smelting.
2. The method as claimed in claim 1, wherein the lance position of step 1) is at a basic pitch of 45-50mm according to a high-low trend, and is blown with oxygen at a distance of 200-300m3The time is 20-30 seconds, which is the basic time interval, and the gun position is reduced.
3. The method as claimed in claim 1, wherein the lime or raw dolomite charge amount in step 2) is controlled to be 500kg per batch at 300-; the oxygen pressure is reduced to 0.65-0.75 MPa.
4. The method of claim 1, wherein the time for adjusting step 4) to the level before performing the operation change in step 2) is controlled to be 20-30 seconds.
CN201810915920.4A 2018-08-13 2018-08-13 Method for inhibiting splashing in earlier stage of converter smelting Active CN108977614B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810915920.4A CN108977614B (en) 2018-08-13 2018-08-13 Method for inhibiting splashing in earlier stage of converter smelting

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810915920.4A CN108977614B (en) 2018-08-13 2018-08-13 Method for inhibiting splashing in earlier stage of converter smelting

Publications (2)

Publication Number Publication Date
CN108977614A CN108977614A (en) 2018-12-11
CN108977614B true CN108977614B (en) 2020-06-16

Family

ID=64552795

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810915920.4A Active CN108977614B (en) 2018-08-13 2018-08-13 Method for inhibiting splashing in earlier stage of converter smelting

Country Status (1)

Country Link
CN (1) CN108977614B (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110699511B (en) * 2019-09-27 2021-07-13 山东钢铁股份有限公司 Method for smelting high-silicon molten iron
CN112280924B (en) * 2020-10-10 2022-03-08 山东莱钢永锋钢铁有限公司 Method for controlling temperature in converter smelting
CN112143853B (en) * 2020-10-13 2022-04-15 长春工业大学 Splash forecasting and splash pressing method and system in AOD furnace smelting process
CN113430327A (en) * 2021-05-14 2021-09-24 阳春新钢铁有限责任公司 Method for controlling splashing and slag overflowing of converter

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104250672A (en) * 2014-05-29 2014-12-31 莱芜钢铁集团有限公司 Efficient dephosphorization method of combined blown converter
CN105525055A (en) * 2014-09-30 2016-04-27 上海梅山钢铁股份有限公司 Method for controlling splashing in less slag smelting decarbonization period of converter

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57123913A (en) * 1981-01-26 1982-08-02 Nisshin Steel Co Ltd Oxygen blowing method for converter

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104250672A (en) * 2014-05-29 2014-12-31 莱芜钢铁集团有限公司 Efficient dephosphorization method of combined blown converter
CN105525055A (en) * 2014-09-30 2016-04-27 上海梅山钢铁股份有限公司 Method for controlling splashing in less slag smelting decarbonization period of converter

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
120t复吹转炉单渣法高拉碳工艺;焦玉莉;《钢铁》;20141031;第49卷(第10期);第30-33页 *
50t转炉前期喷溅控制;杨波 等;《山东冶金》;20130831;第35卷(第4期);第66-67页 *

Also Published As

Publication number Publication date
CN108977614A (en) 2018-12-11

Similar Documents

Publication Publication Date Title
CN108977614B (en) Method for inhibiting splashing in earlier stage of converter smelting
CN110205436B (en) Smelting method for producing IF steel in full-flow low-oxygen level
CN109628697B (en) High-carbon dephosphorization method for smelting medium-high carbon steel grade in converter
CN102943145B (en) Converter smelting method of ultra-low phosphorus steel
CN103614508B (en) Method for smelting high-titanium liquid iron by utilizing converter
CN109022675B (en) Energy supply method by using chemical energy for smelting of full-scrap steel electric arc furnace
CN107012282B (en) Method for improving purity of high-quality ultra-low carbon steel
CN105154623A (en) Efficient alloying method for smelting 38CrMoAl steel
CN112813222A (en) Blowing method for high scrap ratio molten iron of converter
CN104109727A (en) Method for smelting low-phosphorous steel by using semisteel through converter
CN114941049B (en) Converter bottom control method
CN110699511A (en) Method for smelting high-silicon molten iron
CN113699301B (en) Converter smelting method for improving energy production by adopting high-flow oxygen
CN113106190B (en) Steelmaking method for obtaining high-manganese low-phosphorus molten steel through converter smelting
CN113088617B (en) Converter steelmaking method
CN112760449B (en) Smelting method of slag steel used by Considel electric furnace
CN104451022A (en) Method for reducing content of total iron in final slag of dephosphorization furnace
CN110527785B (en) Direct alloying process of manganese ore in semi-steel less-slag smelting converter
CN114622054A (en) Method for improving converter end-point manganese ratio
CN113088616A (en) Method for efficiently controlling manganese content of molten steel during steel making of return steel
CN113278760A (en) Method for defoaming converter double-slag smelting steel slag
CN116814898B (en) Method for reducing total iron in furnace door slag of electric furnace
KR20020052520A (en) Method of low-carbon ferromanganese(LCFeMn) manufacturing by recycling dust containing manganese
CN108570526B (en) Control method for converter non-normal smelting
CN108359817B (en) Sectional type air supply vanadium extraction method for converter

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant