CN111100964A - Method for improving foaming of converter final slag - Google Patents
Method for improving foaming of converter final slag Download PDFInfo
- Publication number
- CN111100964A CN111100964A CN202010108030.XA CN202010108030A CN111100964A CN 111100964 A CN111100964 A CN 111100964A CN 202010108030 A CN202010108030 A CN 202010108030A CN 111100964 A CN111100964 A CN 111100964A
- Authority
- CN
- China
- Prior art keywords
- slag
- foaming
- foam
- converter
- furnace
- 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.)
- Pending
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
- C21C5/36—Processes yielding slags of special composition
-
- 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
- C21C5/36—Processes yielding slags of special composition
- C21C2005/366—Foam slags
-
- 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
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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 relates to the field of converter steelmaking, in particular to a method for improving foaming of converter final slag. In the method, the waste probe used by the converter is reused in the tapping process, so that the foam slag is quickly stabilized, and is stabilized, and then the slag pressing is assisted to better inhibit the foam slag. The invention has simple operation, convenient execution and good use effect, can quickly stabilize the foam slag in a shorter time, reduces the defects of alloy and deoxidizer consumption increase, inclusion increase in steel and the like caused by the foam slag entering the steel ladle, can save the cost and avoid waste.
Description
Technical Field
The invention relates to the field of converter steelmaking, in particular to a method for improving final slag foaming of a converter.
Background
The process of converter steelmaking is to add a slagging agent to remove harmful elements such as phosphorus, sulfur and the like in molten iron, to ensure the harmful elements to enter steel slag, and to oxidize excessive carbon by using blown oxygen to smelt qualified molten steel. In the converter steelmaking process, furnace materials such as light-burned lime, light-burned dolomite, sintered ore and the like need to be added, and slag is formed through a series of complex reactions to promote harmful elements such as phosphorus, sulfur and the like in molten iron to enter the slag. The oxygen blown in through the top-blowing oxygen lance reacts with carbon in the molten iron to generate carbon monoxide gas, and after encountering slag with certain viscosity in the dissipation process, the foaming phenomenon, namely the steel slag foaming phenomenon, is generated. During normal smelting, steel slag foaming degree needs to be controlled through feeding or adjusting the position of an oxygen lance, so that the steel slag foaming degree can not be too low, the difficulty in slag melting is caused, harmful elements are not favorably removed, the steel slag foaming degree is serious, and the defects of aggravation of lining erosion, increase of iron content in steel, loss increase and the like can be caused.
When a steel grade with lower carbon is smelted by the converter, the condition of serious foaming of steel slag is easily generated, once the steel grade is not properly treated, the steel slag is foamed in the steel discharging process, the erosion influence is generated on a furnace lining, the condition of slag discharging at a steel outlet in the later steel discharging stage is also generated, the molten steel slag quantity in a steel ladle is increased, and the defects of increased consumption of deoxidizers and alloys, increased inclusion in steel and the like are caused. The main measures for reducing the foaming of the steel slag at the end point of the converter are as follows: when the temperature of molten steel is insufficient in the last stage of smelting, the temperature is inevitably increased by blowing oxygen, serious foaming is inevitably generated in the process, and the foaming is reduced by blowing nitrogen into an oxygen lance generally.
In the process of tapping, if the steel slag is seriously foamed, tapping must be stopped, the furnace is lifted in time, and a nitrogen lance is used for blowing in nitrogen, so that the foaming phenomenon of the slag can be reduced, but because the mode is used, a large amount of heat is necessarily taken away, the temperature of molten steel is indirectly reduced to different degrees, and generally, the temperature of the molten steel is reduced by 8-10 ℃ every 30 seconds of nitrogen blowing. In addition, serious foaming is found in the tapping process, and the smelting period is prolonged inevitably due to the fact that the furnace is lifted again, so that the production rhythm is influenced.
Disclosure of Invention
In order to effectively solve the foaming phenomenon of steel slag in the tapping process and avoid various defects caused by slag discharging in the later tapping period, the invention provides the method for improving the final slag foaming of the converter.
In order to achieve the aim, the invention provides a method for improving the foaming of converter final slag, which comprises the following steps:
(1) collecting slag and paper waste probes generated in the steelmaking process for later use;
(2) after tapping is started, observing the foaming condition of the furnace slag in the furnace, if obvious foaming of the furnace slag occurs, putting the paper waste probe into the middle rear part of the furnace, burning the paper waste probe to quickly destroy the foam slag so as to break the foam slag, and quickly reducing the foam slag along with the continuous burning to gradually stabilize the foam slag;
(3) when utilizing the spade to press the sediment, every throw 2 ~ 3 shovels, the observation hole is observed the interior sediment of stove and is stabilized the condition: if the slag is stable and does not foam, stopping the operation; if the slag still has foaming phenomenon, the operation is continued until tapping is finished.
Preferably, the paper waste probe in the step (2) includes a TSC (thermo Sample Carbon probe), a TSO (thermo Sample Oxygen probe) waste paper probe and a waste paper probe after refining temperature measurement and Oxygen determination, which are measured by a sublance in the later stage of smelting.
Preferably, the number of the waste paper probes thrown into the furnace in the step (2) is 2-3.
Preferably, the tapping time in the step (2) is 4 minutes, and the tapping speed is 500 kg/sec.
Preferably, the temperature of molten steel in the step (2) is 1620-1670 ℃ and the temperature in the furnace is 1500-1600 ℃.
Preferably, when the slag is pressed by a shovel in the step (3), the amount of the slag is 5-10 kg/shovel.
Preferably, the total amount of the slag charged in the step (3) is about 8-10 shovels.
Preferably, the method for improving the final slag foaming of the converter comprises the following specific steps:
(1) when the shift is handed over, the trolley is hoisted to a lower track platform of the converter furnace by using the hoist, the cooled slag is shoveled into the trolley, the trolley is hoisted to the converter operation platform by using the hoist, and the slag in the trolley is transported into a slag hopper behind the converter furnace to finish the slag preparation work;
(2) collecting TSC and TSO waste paper probes measured by a sublance at the later stage of smelting and waste paper probes after refining, temperature measurement and oxygen determination, and intensively placing the TSC and TSO waste paper probes and the waste paper probes in a probe disposal box behind a furnace for later use;
(3) when molten steel smelting is finished and tapping is started, the foaming condition of the slag in the furnace is observed manually through an observation hole arranged on a fire-blocking door: if the slag is stable, no measures need to be taken; if obvious foaming of the slag occurs, namely the slag generates the condition like laundry foam, 2-3 waste probes are thrown into the middle rear part of the furnace through throwing holes arranged on the fire-blocking door, the foam slag is quickly destroyed through the burning of the paper waste probes, the foam slag is broken, and the foam slag is quickly reduced along with the continuous burning and gradually becomes stable;
(4) along with the gradual reduction of the foam slag, the slag in the slag hopper is thrown into the furnace by the shovel, and the foam slag is further pressed by the slag, so that a better stabilizing effect is achieved. When utilizing the spade to press the sediment, every throw 2 ~ 3 shovels, the observation hole is observed the interior sediment of stove and is stabilized the condition: if the slag is stable and does not foam, stopping the operation; if the slag still has foaming phenomenon, the operation is continued until tapping is finished.
During the converting process, a number of metal droplets are generated as a result of the action of the oxygen stream on the molten bath. After the metal droplets with oxygen fall into the slag, the metal droplets react with FeO to generate a large amount of CO bubbles which are dispersed in the converter to form an emulsion of gas-slag-metal intimate mixture. The total volume of small bubbles dispersed in the slag tends to exceed the volume of the slag itself. The slag becomes a film that envelopes and spaces the bubbles, causing the slag to foam and expand, forming a foamy slag. The waste paper probe mainly comprises paper, floats in the foam slag when being thrown into the furnace, consumes oxygen in CO and FeO in the foam slag through self combustion, breaks small bubbles dispersed in the slag, breaks the balance of gas-slag-metal, and greatly reduces the volume of the foam slag after the gas overflows, thereby achieving the effect of stabilizing the foam slag.
The invention has the beneficial effects that:
the application of the invention can quickly stabilize the foam slag in a short time, and can also recycle the waste, thereby saving the cost and avoiding the waste. The method can be applied to any steel plant and has the advantages of wide application range, high popularization value and the like.
Detailed Description
The following describes an embodiment of the present invention in detail, taking a 120-ton converter of a mountain Steel group Steel works as an example.
A method for improving converter final slag foaming comprises the following specific operation steps:
step 1) during shift, the trolley is lifted to a lower track platform of the converter by the aid of the hoist, about 500 kilograms of cooled slag is shoveled into the trolley, the trolley is lifted to the converter operation platform by the aid of the hoist, the slag in the trolley is conveyed into a slag bucket behind the converter, slag preparation work is completed, and the slag is used for further inhibiting slag foaming in the converter in the later tapping stage.
And 2) collecting the TSC and TSO waste paper probes measured by the sublance at the later stage of smelting and the waste probes after refining, temperature measurement and oxygen determination, and intensively placing the TSC and TSO waste paper probes and the waste probes in a probe disposal box behind the furnace for later use. Under normal conditions, 2 waste probes are generated in one furnace of converter, and 6 waste probes are generated in one furnace of refining. The foaming phenomenon of the converter final slag does not occur in every furnace, and the occurrence probability is about 10-20%, so that the use requirement of subsequent defoaming can be met.
And 3) when the molten steel is smelted and tapping is started, manually observing the foaming condition of the slag in the furnace through an observation hole arranged on the fire door: if the slag is stable, no measures need to be taken; if obvious foaming of the slag occurs, namely the slag generates the condition like laundry foam, the waste probe is thrown into the middle rear part of the furnace through a throwing hole arranged on a fire door, the foam slag is quickly destroyed through the combustion of a paper probe, the foam slag is broken, the foam slag is quickly reduced along with the continuous combustion and gradually tends to be stable, and the foam slag can be ensured to tend to be stable by 2-3 waste probes generally. The tapping time is 4 minutes, the tapping speed is about 500 kilograms per second, the molten steel temperature is 1620-1670 ℃ during tapping, and the temperature in the furnace is 1500-1600 ℃.
And 4) along with the gradual reduction of the foam slag, the slag in the slag hopper is put into the furnace by using a shovel, and the foam slag is further pressed by using the slag, so that a better stabilizing effect is achieved. When utilizing the spade to press the sediment, every throw 2 ~ 3 shovels (5 ~ 10 kg/spade), observe the hole again and observe the interior sediment of stove and stabilize the condition: if the slag is stable and does not foam, stopping the operation; if the slag still has foaming phenomenon, the above operations are continued until tapping is finished, and the slag is stable and does not foam when the total amount of the slag is about 8-10 shovels.
The method is applied to improve the final slag foaming of the converter, the slag foaming can be quickly stabilized, the waste probe is recycled, the cost is reduced, and the temperature drop loss caused by blowing nitrogen to foam slag by lifting the converter slag is avoided. Ensures that the slag is recovered stably in the tapping period, and reduces the consumption of deoxidizers and alloys caused by the slag falling from the furnace mouth and the increase of inclusions in steel. Taking a 120-ton converter as an example, after the foaming of slag is inhibited, the slag content in a ladle can be reduced by about 5%, the deoxidation dosage in tapping is reduced by about 2%, the alloy consumption is reduced by about 0.6%, the inclusion in steel is reduced by about 5%, and the temperature in the whole tapping process is not reduced.
In the prior art, a steel mill adopts a special slag pressing agent for pressing slag, but the price is about 800 yuan per ton. The slag pressing agent also needs to be put into the furnace, and the input amount is about 100kg-200kg per furnace.
The method can quickly stabilize the foam slag within 2-3 minutes. The existing waste probe treatment mode is usually direct discarding, the invention is effectively utilized, and the cost is 0 yuan. The existing slag treatment mode is as follows: the iron resources contained in the iron slag are bought for reuse by screening when the iron slag is transported out of a factory, the cost is about 40 yuan/ton, and the invention effectively utilizes the slag and reduces the cost. In addition, in the existing nitrogen purging mode, the nitrogen cost is about 65 yuan per furnace when the nitrogen unit price is 0.3 yuan per cubic meter, purging is 30 seconds, and the flow is 26000 cubic meters per hour, and the method can reduce the cost by 0.52 yuan per ton steel when the steel tapping amount is 125 tons.
In the process of tapping, if the steel slag is seriously foamed, tapping must be stopped, the furnace is lifted in time, and a nitrogen lance is adopted to blow in nitrogen, so that the foaming phenomenon of the slag can be reduced, but because the mode is adopted, a large amount of heat is necessarily taken away, the temperature of molten steel is indirectly reduced to different degrees, and generally, the temperature of the molten steel is reduced by 8-10 ℃ every 30 seconds of blowing in nitrogen. In addition, serious foaming is found in the tapping process, and the smelting period is prolonged inevitably due to the fact that the furnace is lifted again, so that the production rhythm is influenced. By adopting the method, the situations that the temperature of the molten steel is reduced by blowing in nitrogen and the steel slag is lifted due to serious foaming do not exist, compared with the prior art, the smelting period can be shortened by about 3 minutes, and the economy and the efficiency are improved.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (8)
1. A method for improving the foaming of converter final slag is characterized by comprising the following steps:
(1) collecting slag and paper waste probes generated in the steelmaking process for later use;
(2) after tapping is started, observing the foaming condition of the slag in the furnace, if obvious foaming of the slag occurs, putting the waste probe into the middle rear part of the furnace, burning the waste probe by paper to quickly destroy the foam slag, so that the foam slag is broken, and rapidly reducing the foam slag along with the continuous burning to gradually tend to be stable;
(3) when a shovel is used for pressing slag, every 2-3 shovels are thrown, the observation hole observes the slag stabilizing situation in the furnace: if the slag is stable and does not foam, stopping the operation; if the slag still has foaming phenomenon, the operation is continued until tapping is finished.
2. The method for improving the final slag foaming of the converter according to claim 1, wherein the paper waste probes in the step (2) comprise TSC (TSC-TSO) waste paper probes measured by a sublance in the later stage of smelting and waste paper probes measured by a refining temperature and oxygen measuring device.
3. The method for improving converter final slag foaming according to claim 1, wherein the number of the paper waste probes in the step (2) is 2-3.
4. The method for improving foaming of final slag of a converter according to claim 1, wherein tapping time in step (2) is 4 minutes and tapping speed is 500 kg/sec.
5. The method for improving foaming of the final slag of the converter according to any one of claim 1, wherein the temperature of the molten steel at the time of tapping in the step (2) is 1620-1670 ℃ and the temperature in the converter is 1500-1600 ℃.
6. The method of claim 1, wherein the amount of slag is 5-10 kg/shovel when the slag is pressed by a shovel in the step (3).
7. The method for improving the final slag foaming of the converter according to claim 1, wherein the total amount of the slag charged in the step (3) is about 8-10 shovel.
8. The method for improving the final slag foaming of the converter according to any one of claims 1 to 7, wherein the method for improving the final slag foaming of the converter comprises the following specific operation steps:
(1) when the shift is handed over, the trolley is hoisted to a lower track platform of the converter furnace by using the hoist, the cooled slag is shoveled into the trolley, the trolley is hoisted to the converter operation platform by using the hoist, and the slag in the trolley is transported into a slag hopper behind the converter furnace to finish the slag preparation work;
(2) collecting waste paper probes after TSC and TSO measurement by a sublance in the later smelting period and waste paper probes after refining, temperature measurement and oxygen determination, and intensively placing the waste paper probes in a probe disposal box behind a furnace for later use;
(3) when molten steel smelting is finished and tapping is started, the foaming condition of the slag in the furnace is observed manually through an observation hole arranged on a fire-blocking door: if the slag is stable, no measures need to be taken; if obvious foaming of the slag occurs, namely the slag generates the condition like laundry foam, 2-3 waste probes are thrown into the middle rear part of the furnace through throwing holes arranged on the fire-blocking door, the foam slag is quickly destroyed through the burning of the paper waste probes, the foam slag is broken, and the foam slag is quickly reduced along with the continuous burning and gradually becomes stable;
(4) along with the gradual reduction of the foam slag, the slag in the slag hopper is put into the furnace by using the shovel, and the foam slag is further pressed by using the slag, so that a better stabilizing effect is achieved; when utilizing the spade to press the sediment, every throw 2 ~ 3 shovels, the observation hole is observed the interior sediment of stove and is stabilized the condition: if the slag is stable and does not foam, stopping the operation; if the slag still has foaming phenomenon, the operation is continued until tapping is finished.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010108030.XA CN111100964A (en) | 2020-02-21 | 2020-02-21 | Method for improving foaming of converter final slag |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010108030.XA CN111100964A (en) | 2020-02-21 | 2020-02-21 | Method for improving foaming of converter final slag |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111100964A true CN111100964A (en) | 2020-05-05 |
Family
ID=70427730
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010108030.XA Pending CN111100964A (en) | 2020-02-21 | 2020-02-21 | Method for improving foaming of converter final slag |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111100964A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114085942A (en) * | 2021-10-27 | 2022-02-25 | 重庆钢铁股份有限公司 | Method for reducing slag surface height in converter tapping process |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101487069A (en) * | 2008-01-18 | 2009-07-22 | 上海梅山钢铁股份有限公司 | Foam slag inhibitor for converter |
| CN103540706A (en) * | 2012-07-11 | 2014-01-29 | 攀钢集团研究院有限公司 | Furnace slag bubblization inhibition method |
| CN110023517A (en) * | 2017-01-23 | 2019-07-16 | 日本制铁株式会社 | Inhibit the method and converter refining method of clinker foaming |
-
2020
- 2020-02-21 CN CN202010108030.XA patent/CN111100964A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101487069A (en) * | 2008-01-18 | 2009-07-22 | 上海梅山钢铁股份有限公司 | Foam slag inhibitor for converter |
| CN103540706A (en) * | 2012-07-11 | 2014-01-29 | 攀钢集团研究院有限公司 | Furnace slag bubblization inhibition method |
| CN110023517A (en) * | 2017-01-23 | 2019-07-16 | 日本制铁株式会社 | Inhibit the method and converter refining method of clinker foaming |
Non-Patent Citations (1)
| Title |
|---|
| ***等: "《炼钢生产自动化技术》", 30 November 2006 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114085942A (en) * | 2021-10-27 | 2022-02-25 | 重庆钢铁股份有限公司 | Method for reducing slag surface height in converter tapping process |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5039480A (en) | Method for manufacturing molten metal containing Ni and Cr | |
| CN109136455A (en) | A method of it bessemerizing terminal slag bubble and quickly eliminates | |
| CN113102712B (en) | Steel ladle casting residue recycling method suitable for ultra-low carbon steel | |
| CN105861775A (en) | Smelting process for ultra-low phosphorus steel with high nickel content | |
| CN103045793B (en) | Vacuum smelting device for converter and use method of vacuum smelting device | |
| CN114150100B (en) | Steelmaking method for smelting high-carbon low-phosphorus steel by converter | |
| CN111100964A (en) | Method for improving foaming of converter final slag | |
| CN111270041B (en) | Method for reducing phosphorus content in low-phosphorus steel production tapping process of dephosphorization furnace | |
| UA104595C2 (en) | method for making a steel with low carbon low sulphur low nitrogen using conventional steelmaking Equipment | |
| JP4311097B2 (en) | Method for preventing slag flow in converter | |
| CN112430708B (en) | Recycling method of continuous casting stainless steel liquid casting residues | |
| US6500224B1 (en) | Method for operating a steelmaking furnace during a steelmaking process | |
| Aleksashin et al. | Creation and growth of oxygen-converter steelmaking | |
| CN100540686C (en) | A kind of process for making | |
| CN105112598B (en) | A kind of method that converter product bottom slag is directly used in pneumatic steelmaking | |
| JP5915568B2 (en) | Method of refining hot metal in converter type refining furnace | |
| JP4686880B2 (en) | Hot phosphorus dephosphorization method | |
| JP3333339B2 (en) | Converter steelmaking method for recycling decarburized slag | |
| KR900002710B1 (en) | Rapid decarburiztion steel making process | |
| JP2006274329A (en) | Method for decarburize-refining molten iron | |
| CN113789425B (en) | Method for smelting return high silicon steel water by converter | |
| CN107034332A (en) | A kind of molten iron pre-desulfurization method | |
| Bilgiç | Effect of bottom stirring on basic oxygen steelmaking | |
| Wang et al. | New steelmaking process based on clean deoxidation technology | |
| RU2628588C1 (en) | Procedure of melting steel in 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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200505 |