CN109439848B - Ladle and ferroalloy vacuum refining system and method - Google Patents
Ladle and ferroalloy vacuum refining system and method Download PDFInfo
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- CN109439848B CN109439848B CN201811560888.9A CN201811560888A CN109439848B CN 109439848 B CN109439848 B CN 109439848B CN 201811560888 A CN201811560888 A CN 201811560888A CN 109439848 B CN109439848 B CN 109439848B
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- 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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/10—Handling in a vacuum
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- 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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/072—Treatment with gases
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- 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
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- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
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Abstract
The application provides a ladle, ferroalloy vacuum refining system and method, the method includes that ferrosilicon molten iron and liquid manganese-rich slag are filled into the ladle for ferroalloy circulating vacuum refining; placing the ladle in a vacuum treatment position, and connecting a bottom blowing pipeline connected with a first air brick to perform bottom blowing stirring with small air volume; pre-vacuumizing; raising the ladle to a target treatment height, and sequentially starting other stages of pumps except for an Nth stage of mechanical vacuum pump to continuously reduce the pressure in the vacuum chamber so as to perform vacuumizing operation, and continuously increasing the gas quantity of bottom blowing gas while reducing the pressure so as to enable ferrosilicon molten iron to start circulating flow to enter the vacuum chamber, then downwards flushing the ferrosilicon molten iron into liquid manganese-rich slag, uniformly mixing the ferrosilicon molten iron and the liquid manganese-rich slag, and completing desilication manganese reduction reaction; breaking vacuum after the vacuum refining cycle is completed, and lowering the liquid level of the ferrosilicon molten iron to a horizontal track; and carrying out refining operation on the refined molten iron after the slag skimming operation.
Description
Technical Field
The application relates to a ladle and ferroalloy vacuum refining system and method, and belongs to the technical field of metallurgy.
Background
With the increase of the demand of iron and steel enterprises for fine ferroalloy, the ladle refining process is increasingly widely applied to the ferroalloy industry. The ladle can be used for better refining of manganese-silicon alloy, depletion of medium-low carbon ferromanganese slag and the like.
The common process flow comprises the linkage operation of a manganese-silicon alloy submerged arc furnace, a refining electric furnace and a ladle shaking furnace. The refining electric furnace is operated intermittently, the manganese-silicon alloy submerged arc furnace is operated continuously, the refining electric furnace and the manganese-silicon alloy submerged arc furnace are discharged simultaneously, and medium-low carbon ferromanganese slag (containing about 20% of manganese) produced by the refining electric furnace is poured into a ladle, and the produced molten iron is used as a final product, namely medium-low carbon ferromanganese. And weighing the manganese-silicon alloy melt refined by the manganese-silicon alloy submerged arc furnace, and adding the weighed manganese-silicon alloy melt into a ladle. The ladle rotates at a certain rotation speed, under good dynamics condition, si in the manganese-silicon alloy rapidly reduces MnO in the medium-low carbon manganese iron slag, so that the purpose of manganese increasing and desilication is achieved, and the ladle is tilted to pour out waste residues after the MnO in the slag is depleted to a certain requirement. And the intermediate alloy melt after removing part of silicon is added into a refining electric furnace again for further refining. After tapping, the refining electric furnace reloads one half of the total ingredients of high-grade manganese ore and lime for melting, after the intermediate alloy subjected to shaking pre-refining is blended, the rest one half of manganese ore and lime are added into the furnace for further desilication and manganese lifting refining, and tapping is carried out after sampling analysis is qualified, so that a periodic operation is completed.
The principle of the production of low-carbon ferromanganese is mainly that silicon in ferrosilicon and manganese oxide in liquid manganese slag are subjected to oxidation-reduction reaction in a ladle to produce Mn and SiO 2 The reaction is a severe exothermic reaction, and the ladle shaking production can fully utilize the heat of waste slag and the heat released by the reaction of silicon and MnO in the slag.
2(MnO)+[Si]＝2[Mn]+(SiO 2 )。
The ladle is used for putting slag and molten iron into the ladle for shaking, so that dynamic conditions are improved, slag and molten iron are mixed, a reaction interface is increased, a diffusion process is accelerated, and reaction time is shortened. Under the driving action of the eccentric shaft, the rocker ladle horizontally and eccentrically translates. Due to the action of the ladle shaking wall and the inertia of the liquid melt, the liquid alloy and the slag swing and rotate relative to the ladle body, and the phenomenon of iron rolling emulsification occurs, so that the contact area of slag and gold is effectively enlarged, the mass transfer process is accelerated, and the completion of chemical reaction is promoted.
The main factors affecting the interface movement within the rocker paddle are: rotational speed, eccentricity, liquid level height, upper-lower liquid ratio, rocker diameter and the like, wherein the rotational speed is the most main influencing factor, and the eccentricity is the second.
The ladle shaking equipment mainly comprises a ladle (containing a lining), a cradle, an eccentric shaking device, a transmission device, a tipping device, a lubrication system, a control system and the like.
Prior art related to the application
The technical scheme in the first prior art is as follows:
the ladle shaking-electric furnace method is a main method for producing medium-low carbon ferromanganese. The typical process for producing low-carbon ferromanganese is to store liquid silicon-manganese alloy produced by a manganese-silicon alloy submerged arc furnace in a ladle, store manganese-rich slag produced by a refining electric furnace in a slag ladle, slowly add the liquid silicon-manganese alloy and the manganese-rich slag into a ladle by adopting a casting crane to carry out silicon-manganese alloy desilication reaction, wherein the sum of the volumes of the liquid silicon-manganese alloy and the manganese-rich slag is generally not more than 1/2 of the effective volume of the ladle. The ladle shaking mechanism is started, and the ladle is shaken horizontally under the action of the eccentric shaft for 10-15 minutes. Tilting the ladle by adopting an overhead travelling crane, pouring out the alloy which is well rocked in the ladle, and pouring slag in the ladle. The alloy is added into a refining electric furnace for refining, and the slag is subjected to water quenching treatment. And after refining in the refining electric furnace is finished, discharging molten iron, and casting.
The ladle reactor is internally provided with slag-metal liquid-liquid two-phase reaction, and the reaction rate of slag and metal at high temperature is far greater than the mass transfer rate between the two phases, so the mass transfer step is a control link. The adoption of the eccentric rotary shaking ladle can greatly promote the mixing of the two liquid phases of the slag and the gold, and increase the contact area of slag Jin Liangxiang, thereby accelerating the reaction of the two phases of the slag and the gold.
Drawbacks of the first prior art:
1. the ladle refining process has difficult dust removal design and poor dust removal effect.
2. The filling coefficient is lower during ladle refining, the whole packing is needed to be replaced when the refractory is replaced, and the unit consumption of the refractory is increased.
3. The ladle refining has higher requirements on mechanical equipment of the ladle device, and the control refining is mainly or empirically performed, so that the reaction degree of the ladle cannot be accurately controlled.
4. The ladle wall, slag and molten iron relatively move in the ladle refining process, the side wall is repeatedly flushed, and the temperature drop of the molten iron is large.
However, the determination of the technological parameters of the domestic shake ladle mainly depends on field experience, and parameters such as the diameter, the eccentricity, the rotating speed and the like of the shake ladle are determined empirically. For example, the state iron alloy factory in China adopts the method of "listening to judge the movement state of slag and gold" to judge the mixing condition of slag and gold. Some manufacturers rely on the flue gas at the furnace mouth to judge the progress of the reaction.
The ladle is driven by the eccentric shaft to horizontally and eccentrically translate, and the ladle body, slag and molten iron relatively move, so that the reaction is promoted. The ladle wall is continuously flushed by molten iron and slag, and early erosion of the ladle wall by acid slag is a main reason for erosion of the ladle shaking refractory. The eccentricity of the eccentric shaft of the rocker ladle can be adjusted, but the relative movement of the ladle body and the internal high-temperature melt is still realized. Because the reaction of silicon and oxygen in the ladle is rapid and violent, slag formed in the middle and early stage has serious erosion to the furnace lining, the service life of the ladle is very low, and the ladle is generally about 200-300 furnaces. The continuous relative movement of the molten iron and slag and the ladle wall causes great temperature drop of the molten iron and sometimes affects the next refining.
The ladle shaking capacity used by iron alloy enterprises in China is small at present, and the effective volume of the vast majority of ladle shaking is 5-8m 3 The production efficiency is low. The refractory material in the small-sized rocker ladle has the conditions of bad working environment, low service life, low operation rate, high production cost and the like. Meanwhile, in order to ensure the effect of the shake-pack, the filling coefficient of the shake-pack is not more than 0.5.
In the ladle smelting process, no good dust removal measures are generally available. The ladle needs to be frequently replaced with a furnace lining and integrally hoisted, so that the design of the dust hood is difficult, while some patents propose ideas, more manufacturers have no good dust falling measures because of difficult implementation. When the ladle is used for adding iron and slag, the ladle refining process and the ladle are finished, the ladle is discharged, and a large amount of smoke dust is generated.
In order to satisfy the reaction space in the ladle, the typical filling factor is not more than 0.6, and usually not more than 0.5, that is, 15m3 (total volume of molten iron+slag), and the internal space after the ladle is built is generally about 30m 3. And when the packing is replaced, the whole packing is required to be replaced, so that the unit consumption of the refractory materials for refining the ferroalloy ladle is very large.
Prior art II related to the application
The technical scheme of the second prior art is as follows:
the development of a single-nozzle vacuum refining furnace for more than thirty years shows that theory and practice: the furnace type vacuum refining furnace has the advantages of high refining efficiency, simple structure, less loss of refractory materials, high argon utilization rate, suitability for smelting of small-capacity ladles, and the like, and is mainly used for vacuum refining of molten steel of iron and steel enterprises.
Drawbacks of the second prior art:
the existing single-nozzle vacuum refining furnace is mainly used for vacuum refining of molten steel of iron and steel enterprises, and is not applied to molten iron refining of iron alloy production enterprises.
Accordingly, providing a new ladle for ferroalloy cyclic vacuum refining, ferroalloy vacuum refining system and method have become a technical problem to be solved in the art.
Disclosure of Invention
In order to solve the above-described drawbacks and disadvantages, an object of the present application is to provide a ladle for cyclic vacuum refining of ferroalloys.
It is another object of the present application to provide a ferroalloy vacuum refining system comprising the ladle for ferroalloy cyclic vacuum refining.
It is still another object of the present application to provide a ferroalloy vacuum refining method that utilizes the ferroalloy vacuum refining system. The application mainly solves the smoke dust control problem in the ladle refining technology used in the prior art, and simultaneously controls the circulating flow speed of molten iron by controlling the vacuum degree and the flow of bottom blowing stirring gas, thereby accelerating the reaction speed of liquid manganese-rich slag and ferrosilicon molten iron; in addition, the application can fill the molten iron more fully, thereby saving the comprehensive refractory consumption of smelting and realizing ladle refining with large capacity.
In order to achieve the above object, in one aspect, the present application provides a ladle for ferroalloy cyclic vacuum refining, wherein the ladle for ferroalloy cyclic vacuum refining comprises a ladle body and a vacuum chamber; the vacuum chamber is of a cylindrical structure with an open lower end; the vacuum chamber is positioned above the bag body;
the vacuum chamber comprises an upper part of the vacuum chamber and an immersion pipe, the bottom end of the immersion pipe is of a slope structure, the lower end of the immersion pipe is inserted into the ferrosilicon molten iron, and the lower end of the immersion pipe is as close to slag Jin Yemian formed between the ferrosilicon molten iron and liquid manganese-rich slag as possible;
the bottom surface of the bag body is provided with a first air brick which is positioned near the center of the dipping pipe and is connected with a bottom blowing valve station through a bottom blowing pipeline;
an inlet formed in the top end of the outer wall of the upper part of the vacuum chamber is connected with an N-level mechanical vacuum pump.
According to a specific embodiment of the application, in the ladle, the distance between the bottom end of the dipping pipe and the slag-metal liquid level is 50-200mm.
The dipping pipe is vacuumized and then inserted into ferrosilicon molten iron, and the distance between the bottom end of the dipping pipe and the slag-metal liquid level is 50-200mm; however, in the embodiment of the application, the distance can be adjusted according to the reaction state, and if the slag-metal reaction is too severe, the distance can be increased appropriately.
According to the concrete embodiment of the application, in the ladle, the bottom surface of the ladle body is also provided with a plurality of air bricks which are arranged outside the dip pipe;
preferably, the number of the air bricks is 2-4.
Wherein, a plurality of air bricks arranged outside (periphery) of the dipping pipe can promote the reaction in the whole package body and reduce dead zones.
On the other hand, the application also provides a ferroalloy vacuum refining system, wherein the ferroalloy vacuum refining system comprises the ladle, a refining electric furnace, a manganese silicon alloy submerged arc furnace, a ladle car and a jacking device for ferroalloy circulating vacuum refining;
the refining electric furnace is used for producing liquid manganese-rich slag, receiving molten iron obtained after ladle cyclic vacuum refining for ferroalloy cyclic vacuum refining and refining the molten iron;
the manganese-silicon alloy submerged arc furnace is used for producing ferrosilicon molten iron;
the ladle for ferroalloy cyclic vacuum refining is used for containing ferrosilicon molten iron and liquid manganese-rich slag and is used for carrying out cyclic vacuum refining in the ladle;
the ladle car is used for conveying the ladle for ferroalloy circulating vacuum refining;
the jacking device is used for placing the ladle car and lifting the ladle for ferroalloy cyclic vacuum refining to a target treatment height.
According to a specific embodiment of the application, in the system, the refining equipment (namely the ladle for ferroalloy circulating vacuum refining provided by the application) is a single-nozzle refining furnace with larger stirring capacity.
In still another aspect, the present application provides a ferroalloy vacuum refining method, wherein the ferroalloy vacuum refining method uses the ferroalloy vacuum refining system, and the ferroalloy vacuum refining method includes the following steps:
(1) Filling ferrosilicon molten iron produced by a manganese-silicon alloy submerged arc furnace and liquid manganese-rich slag produced by a refining electric furnace into a ladle for ferroalloy circulating vacuum refining; placing the ladle in a vacuum treatment position, and connecting a bottom blowing pipeline connected with a first air brick to perform bottom blowing stirring with small air volume;
(2) Starting an N-stage pump of the N-stage mechanical vacuum pump, and when the pressure in the dipping pipe reaches the target pressure, completing pre-vacuumizing and preparing for vacuum treatment;
(3) After the ladle is lifted to the target treatment height, the pressure in the vacuum chamber is continuously reduced by sequentially starting other stages of pumps except for an Nth stage of mechanical vacuum pump, so that vacuumizing operation is performed, the gas quantity of bottom blowing gas is continuously increased while the pressure is reduced, so that ferrosilicon molten iron starts to circularly flow into the vacuum chamber, and then the ferrosilicon molten iron is lowered and rushed into liquid manganese-rich slag, so that the uniform mixing of the ferrosilicon molten iron and the liquid manganese-rich slag is realized, and the desilication and manganese reduction reaction is completed;
(4) After the vacuum refining cycle is completed, breaking vacuum by adopting nitrogen, and after the liquid level of the ferrosilicon molten iron is reduced, reducing the ladle from the target processing height to a horizontal track;
(5) After slag skimming operation is carried out on the ladle, the obtained refined molten iron is added into a refining electric furnace to carry out refining operation.
According to a specific embodiment of the application, in the method, the volume ratio of the liquid manganese-rich slag to the ferrosilicon water is 1.5-2:1.
According to a specific embodiment of the application, in the method, the manganese content of the liquid manganese-rich slag is more than 15% based on 100% of the total weight of the liquid manganese-rich slag;
in a specific embodiment of the application, the liquid manganese rich slag used contains about 20% manganese.
According to a specific embodiment of the application, in the method, the silicon content of the ferrosilicon iron is 14-28% based on 100% of the total weight of the ferrosilicon iron; in a specific embodiment of the present application, the ferrosilicon iron used contains about 27% silicon.
According to a specific embodiment of the application, in the method, the small-air-amount bottom-blowing stirring is performed under the air amount of 25-50L/min (such as 30L/min). Wherein the amount of gas is related to the throughput.
According to a specific embodiment of the present application, in the method, the bottom blowing gas is an inert gas, which includes nitrogen or argon.
According to a specific embodiment of the present application, in the method, the step (2) includes: and starting an Nth stage pump of the N-stage mechanical vacuum pump, controlling the pressure in the dipping pipe to reach 10KPa, and completing pre-vacuumizing to prepare for vacuum treatment.
According to a specific embodiment of the present application, in the method, in the step (3), the target treatment height may be calculated according to a specific ladle and a size of the vacuum chamber, so long as the vacuum chamber dip tube is inserted into molten iron by 50-200mm after reaching the vacuum degree; in embodiments of the application, the height is typically 400-600mm.
According to a specific embodiment of the present application, in the method, the step (3) includes:
after the ladle is lifted to the target processing height, when the pressure in the vacuum chamber reaches 5KPa, starting an N-1 stage pump of the N-stage mechanical vacuum pump; when the pressure in the vacuum chamber reaches below 2KPa, starting an N-2 stage pump of the N-stage mechanical vacuum pump to perform vacuumizing operation; simultaneously increasing the gas quantity of the bottom blowing gas to 50-70L/min; when the pressure in the vacuum chamber is reduced to below 133Pa, all bottom blowing pipelines are opened, and the total flow of bottom blowing gas is continuously increased to 120-150L/min.
According to a specific embodiment of the present application, in the method, in the step (4), the completion of the vacuum refining cycle may be determined by observation with a high-temperature vacuum camera disposed in the vacuum chamber, specifically: the state of the reaction fume is observed by the high temperature vacuum camera, and the darkening of the color of the small flame of the fume is generally considered to be basically completed.
In addition, the specific requirement of the specific amplitude of the reduction of the liquid level of the ferrosilicon molten iron in the step (4) is not required, and the ferrosilicon molten iron can be calculated according to the field operation requirement by a person skilled in the art.
According to the embodiment of the application, in the method, the vacuum degree and the flow rate of the bottom blowing stirring accompanying gas can be adjusted according to the intensity of the reaction, but the method needs to ensure that the vacuum degree and the flow rate of the bottom blowing stirring accompanying gas are all within the scope defined by the application.
According to a specific embodiment of the application, the bottom end of the dipping pipe of the vacuum chamber is of a slope structure (i.e. the slope structure formed after the bottom end of the cylindrical dipping pipe is beveled), and after the lower end of the dipping pipe is inserted into the ferrosilicon molten iron, the structure can enable the descending side of the vacuum chamber (i.e. the descending side of the ferrosilicon molten iron, which is contacted with the liquid manganese-rich slag when the ferrosilicon molten iron descends in the circulating flow process of the ferrosilicon molten iron) to be lower than the ascending side (i.e. the ascending side of the ferrosilicon molten iron, which is the side of the ferrosilicon molten iron, which ascends into the vacuum chamber in the circulating flow process of the ferrosilicon molten iron), so that the ferrosilicon molten iron can fully contact and react with slag in the descending process.
In the ferroalloy vacuum refining method provided by the application, firstly, a ladle for ferroalloy circulating vacuum refining is placed on a ladle car, then liquid manganese-rich slag is added into the ladle body of the ladle, and a ferrosilicon iron (liquid manganese silicon alloy) is directly discharged into the ladle body of the ladle by a manganese silicon alloy submerged arc furnace; then the ladle car is driven to a vacuum treatment position, a quick connector of a bottom blowing valve station is connected, the bottom blowing valve station of the ladle is started, and inert gas is blown in; then lifting the ladle car through a jacking device, inserting the lower end of a vacuum chamber dipping pipe into molten iron, starting an N-level mechanical vacuum pump, and when the pressure in the vacuum chamber reaches a certain degree, enabling liquid manganese-silicon alloy to start to circularly flow, and then entering the vacuum chamber and then descending to flush into manganese-rich slag; the liquid manganese-silicon alloy circulates in the vacuum chamber for a plurality of times, after slag and gold are uniformly mixed and desilication and reduction of manganese reaction are completed, vacuumizing and blowing are stopped, and the primary desilication reaction is completed; then breaking vacuum, lowering the ladle car, and starting the ladle car to a hoisting position for subsequent treatment; and finally, opening the ladle to a slag removing position, completing slag removing operation under a slag removing dust hood, and hanging the molten iron to a refining electric furnace to perform iron charging operation.
In the steelmaking field, slag coiling is not expected to occur in RH treatment or VD treatment, slag coiling phenomenon can occur when the consumption of inert gas is increased, and in the technical scheme provided by the application, ferroalloy refining is performed by utilizing the slag coiling phenomenon, namely slag-metal reaction is performed, and the refining process is not afraid of oxidation of molten iron.
According to the specific embodiment of the application, in the vacuum degassing process, air is blown through the air bricks arranged at the bottom end of the ladle body, so that the flow of ferrosilicon molten iron and liquid manganese-rich slag is promoted; refining of the small-capacity ladle can be realized through the single-vacuum-chamber refining furnace; the vacuum pump system adopts an N-level mechanical vacuum pump, so that energy is saved, flexible control of vacuum degree can be realized, production cost is reduced, the vacuum pump system does not need high vacuum degree, only needs to maintain a certain vacuum degree for realizing circulation of ferrosilicon water, and simultaneously, when the dipping pipe is inserted into the ferrosilicon water, the bottom end of the dipping pipe of the vacuum chamber is close to slag Jin Yemian as much as possible for realizing good slag-metal reaction; the method is characterized in that large-gas stirring is adopted, the circulated ferrosilicon molten iron is continuously contacted with a slag layer, and meanwhile, the molten iron is continuously contacted and reacted with the slag layer in the circulating flow process; the slag layer and the ladle wall basically keep relative static, so that the overflow of flue gas in the treatment process is reduced, the reaction of molten iron and slag is mainly carried out under the slag layer in the vacuum chamber, and the flue gas can be pumped away through a mechanical vacuum pump system and discharged after the temperature and dust reduction treatment is carried out on the flue gas.
Compared with the traditional ladle shaking method, the application strengthens the slag-gold reaction speed and controls the reaction area in the alloy refining process by adopting a vacuum refining mode, and can improve the refining quality and efficiency;
the refining is carried out in the ladle, so that the operations of adding the ladle into the ladle and tapping from the ladle to the ladle are reduced, a dust removal system for ladle refining is not required, the overflow of smoke dust in the refining process can be prevented, and the smoke dust pollution is avoided;
the technical scheme provided by the application reduces the times of unpacking operation and reduces the heat loss; the treatment time is shortened, so that the temperature loss in the refining process is reduced;
the filling coefficient of the ladle used by the application is higher, can reach more than 0.8, and the main reaction is carried out at a slag-metal interface, so that the scouring of the ladle refractory is reduced, the service life is prolonged, and the comprehensive refractory consumption is reduced.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for the description of the embodiments will be briefly described, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to the drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic view showing a ladle for cyclic vacuum refining of ferroalloy according to example 1 of the present application;
fig. 2 is a schematic structural diagram of a ferroalloy vacuum refining system provided in embodiment 2 of the present application.
The main reference numerals illustrate:
1. a first air brick;
2. a bag body;
3. inert gas bubbles;
4. ferrosilicon iron;
5. liquid manganese-rich slag;
6. a vacuum chamber;
7. a three-stage mechanical vacuum pump;
8. a bottom blowing valve station;
9. a ladle car;
10. a jacking device;
11. ladle for cyclic vacuum refining of ferroalloys;
12. a refining electric furnace;
13. a manganese-silicon alloy submerged arc furnace;
14. conventional ladles.
Detailed Description
In order to make the technical features, objects and advantageous effects of the present application more clearly understood, the technical aspects of the present application will now be described in detail with reference to the following specific examples, but should not be construed as limiting the scope of the present application.
Example 1
The embodiment provides a ladle for ferroalloy circulating vacuum refining, wherein the schematic structure of the ladle is shown in fig. 1, and the ladle comprises a ladle body 2 and a vacuum chamber 6 as can be seen from fig. 1; the ladle body 2 is used for containing ferrosilicon molten iron 4 and liquid manganese-rich slag 5, and the vacuum chamber 6 is of a cylindrical structure with an open lower end; the vacuum chamber 6 is positioned above the bag body 2;
the vacuum chamber 6 comprises a vacuum chamber upper part and an immersion pipe, the bottom end of the immersion pipe is of a slope structure, the lower end of the immersion pipe is inserted into the ferrosilicon molten iron, and the lower end of the immersion pipe is as close to slag Jin Yemian formed between the ferrosilicon molten iron and liquid manganese-rich slag as possible;
the bottom surface of the bag body 2 is provided with a first air brick 1, the first air brick 1 is positioned near the center of the dipping pipe and is connected with a bottom blowing valve station 8 through a bottom blowing pipeline;
an inlet formed in the top end of the outer wall of the upper part of the vacuum chamber is connected with a three-stage mechanical vacuum pump 7;
in the embodiment, the distance between the bottom end of the dipping pipe and the slag gold liquid level is 50-200mm;
in this embodiment, 2 air bricks are further disposed on the bottom surface of the bag body 2, and are disposed outside the dip pipe.
Example 2
The embodiment provides a ferroalloy vacuum refining system, wherein the structural schematic diagram of the ferroalloy vacuum refining system is shown in fig. 2, and as can be seen from fig. 2, the system comprises a ladle 11 for ferroalloy cyclic vacuum refining, a refining electric furnace 12, a manganese silicon alloy submerged arc furnace 13, a ladle car 9, a jacking device 10 and a conventional ladle 14, which are provided in embodiment 1;
the refining electric furnace 12 is an electric furnace for producing liquid manganese-rich slag, receiving molten iron obtained after the circulating vacuum refining of the ladle 11 for the circulating vacuum refining of the ferroalloy and refining the molten iron;
the manganese-silicon alloy submerged arc furnace 13 is a manganese-silicon alloy submerged arc furnace for producing ferrosilicon molten iron;
the ladle 11 for ferroalloy cyclic vacuum refining is a ladle for containing ferrosilicon molten iron and liquid manganese-rich slag and carrying out cyclic vacuum refining therein;
the conventional ladle 14 is a ladle for holding a product obtained by cyclic vacuum refining;
a ladle car 9 for transporting the ladle 11 for the cyclic vacuum refining of ferroalloy;
the jacking device 10 is used for placing the ladle car 9 and lifting the ladle 11 for cyclic vacuum refining of ferroalloy to a target treatment height.
Example 3
The embodiment provides a ferroalloy vacuum refining method, wherein the ferroalloy vacuum refining method is realized by adopting the ferroalloy vacuum refining system provided by the embodiment 2, and the method comprises the following specific steps:
step 1: the liquid manganese-rich slag containing about 20wt% of manganese of the refining electric furnace was discharged into the ladle body of the ladle for ferroalloy cyclic vacuum refining provided in example 1, about 18 tons, while the ferrosilicon iron was discharged from the manganese-silicon alloy submerged arc furnace into the ladle (the molten iron contains about 27wt% of silicon), about 15 tons of ferrosilicon iron per furnace, and the lower end of the dipping pipe of the vacuum chamber was inserted into the ferrosilicon iron. Opening the ladle car from the furnace of the manganese-silicon alloy submerged arc furnace to a vacuum treatment position; and (3) connecting a bottom blowing pipeline connected with the first air brick to perform bottom blowing stirring with a small air volume of 30L/min by using inert gas so as to form inert gas bubbles 3.
Step 2: and pre-vacuumizing, starting a third stage pump of the third stage mechanical vacuum pump, and preparing for vacuum treatment after the vacuum chamber dip pipe reaches 10 KPa.
Step 3: the ladle car runs on the jacking device, the jacking device is started, the ladle car is lifted to the target height for treatment, and the depth of the vacuum chamber dip pipe inserted into the ferrosilicon molten iron is about 200mm; and starting the vacuumizing operation.
Step 4: when the pressure in the vacuum chamber reaches 5KPa, starting a second stage pump of the third stage mechanical vacuum pump; when the pressure in the vacuum chamber is lower than 2KPa, a first-stage pump of the three-stage mechanical vacuum pump is started; simultaneously increasing the gas quantity of bottom blowing gas (inert gas) to 70L/min; when the vacuum pressure in the vacuum chamber is reduced to below 133Pa, the total flow of bottom blowing gas (inert gas) is increased to 150L/min, and at the moment, three air bricks are simultaneously opened.
Step 5: according to the calculation of related literature, the circulation flow of the vacuum refining device is about 8t/min, so that the ferrosilicon molten iron can finish a circulation process for less than 2 min. Taking the circulation factor as 3, and completing the pre-desilication reaction within 6 minutes; when refining is carried out by adopting the conventional ladle shaking technology in the field, the period is generally more than 10-15 min.
Step 6: after the vacuum refining cycle is completed, nitrogen is adopted to break vacuum, after the liquid level of molten iron is reduced, a ladle car is lowered onto a rail, and the ladle car is opened to a lifting position for subsequent treatment.
Step 7: and (3) hoisting the ladle to a slag removing position, and starting slag removing operation after the slag removing and dedusting system is started.
Step 8: after the slag skimming is completed, the ladle is hoisted to a refining electric furnace to carry out refining operation.
The foregoing description of the embodiments of the application is not intended to limit the scope of the application, so that the substitution of equivalent elements or equivalent variations and modifications within the scope of the application shall fall within the scope of the patent. In addition, the technical features and the technical features, the technical features and the technical application can be freely combined for use.
Claims (9)
1. The ferroalloy vacuum refining method is characterized by utilizing a ferroalloy vacuum refining system, wherein the ferroalloy vacuum refining system comprises a ladle for ferroalloy circulating vacuum refining, a refining electric furnace (12), a manganese silicon alloy submerged arc furnace (13), a ladle car (9) and a jacking device (10);
the ladle for ferroalloy cyclic vacuum refining is used for containing ferrosilicon molten iron and liquid manganese-rich slag and carrying out cyclic vacuum refining in the ladle;
the refining electric furnace (12) is an electric furnace for producing liquid manganese-rich slag, receiving molten iron obtained after ladle cyclic vacuum refining for ferroalloy cyclic vacuum refining and refining the molten iron;
the manganese-silicon alloy submerged arc furnace (13) is a manganese-silicon alloy submerged arc furnace for producing ferrosilicon molten iron;
the ladle car (9) is used for conveying the ladle for ferroalloy circulating vacuum refining;
the jacking device (10) is used for placing the ladle car (9) and lifting the ladle for ferroalloy circulating vacuum refining to a target treatment height;
wherein, the ladle for ferroalloy circulating vacuum refining comprises a ladle body (2) and a vacuum chamber (6); the ladle body (2) is used for containing ferrosilicon molten iron and liquid manganese-rich slag, and the vacuum chamber (6) is of a cylindrical structure with an open lower end; the vacuum chamber (6) is positioned above the bag body (2);
the vacuum chamber (6) comprises a vacuum chamber upper part and an immersion pipe, the bottom end of the immersion pipe is of a slope structure, the lower end of the immersion pipe is inserted into ferrosilicon molten iron, and the lower end of the immersion pipe is as close as possible to slag Jin Yemian formed between the ferrosilicon molten iron and liquid manganese-rich slag; the distance between the bottom end of the dipping pipe and the slag-metal liquid level is 50-200mm;
the bottom surface of the bag body (2) is provided with a first air brick (1), the first air brick (1) is positioned near the center of the dipping pipe and is connected with a bottom blowing valve station (8) through a bottom blowing pipeline;
an inlet formed in the top end of the outer wall of the upper part of the vacuum chamber is connected with an N-level mechanical vacuum pump;
the ferroalloy vacuum refining method comprises the following steps:
(1) Filling ferrosilicon molten iron produced by a manganese-silicon alloy submerged arc furnace and liquid manganese-rich slag produced by a refining electric furnace into a ladle body of a ladle for ferroalloy circulating vacuum refining; placing the ladle in a vacuum treatment position, and connecting a bottom blowing pipeline connected with a first air brick to perform bottom blowing stirring with small air volume;
(2) Starting an N-stage pump of the N-stage mechanical vacuum pump, and when the pressure in the dipping pipe reaches the target pressure, completing pre-vacuumizing and preparing for vacuum treatment;
(3) After the ladle is lifted to the target processing height, when the pressure in the vacuum chamber reaches 5KPa, starting an N-1 stage pump of the N-stage mechanical vacuum pump; when the pressure in the vacuum chamber reaches below 2KPa, starting an N-2 stage pump of the N-stage mechanical vacuum pump to perform vacuumizing operation; simultaneously increasing the gas quantity of the bottom blowing gas to 50-70L/min; when the pressure in the vacuum chamber is reduced to below 133Pa, opening all bottom blowing pipelines, continuously increasing the total flow of bottom blowing gas to 120-150L/min, so that after the ferrosilicon molten iron starts to circularly flow into the vacuum chamber, then descending and flushing the ferrosilicon molten iron into liquid manganese-rich slag, uniformly mixing the ferrosilicon molten iron and the liquid manganese-rich slag, and completing desilication reduction manganese reaction;
(4) After the vacuum refining cycle is completed, breaking vacuum by adopting nitrogen, and after the liquid level of the ferrosilicon molten iron is reduced, reducing the ladle from the target processing height to a horizontal track;
(5) After slag skimming operation is carried out on the ladle, the obtained refined molten iron is added into a refining electric furnace to carry out refining operation.
2. A method according to claim 1, characterized in that the bottom surface of the bag body (2) is further provided with a number of air bricks, which are arranged outside the dip tube.
3. The method of claim 2, wherein the number of air bricks is 2-4.
4. The method of claim 1, wherein the volume ratio of the liquid manganese-rich slag to ferrosilicon water is 1.5-2:1.
5. The method according to claim 1 or 4, characterized in that the manganese content of the liquid manganese-rich slag is more than 15% based on 100% by total weight of the slag.
6. The method according to claim 1 or 4, wherein the silicon content is 14-28% based on 100% of the total weight of the ferrosilicon iron.
7. The method according to claim 1 or 4, wherein the small-air-amount bottom-blowing stirring is performed at an air amount of 25-50L/min.
8. The method of claim 1 or 4, wherein the bottom blowing gas is an inert gas comprising nitrogen or argon.
9. The method according to claim 1 or 4, wherein the step (2) comprises: and starting an Nth stage pump of the N-stage mechanical vacuum pump, controlling the pressure in the dipping pipe to reach 10KPa, and completing pre-vacuumizing to prepare for vacuum treatment.
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| CN112094976B (en) * | 2020-10-11 | 2024-06-14 | 宁夏昌茂祥冶炼有限公司 | Bottom rotary ferroalloy smelting system |
| CN115232923B (en) * | 2022-07-27 | 2023-06-02 | 辽宁科技大学 | Method for refining molten steel by VD furnace |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0589443U (en) * | 1992-05-12 | 1993-12-07 | 新日本製鐵株式会社 | Immersion pipe for molten steel treatment |
| JP2000119730A (en) * | 1998-10-08 | 2000-04-25 | Nippon Steel Corp | Method for refining molten steel under reduced pressure |
| CN105624438A (en) * | 2016-02-02 | 2016-06-01 | 镇远县鸿丰新材料有限公司 | Method for refining low-carbon ferromanganese alloy through poor-manganese slag |
| CN207958424U (en) * | 2018-02-06 | 2018-10-12 | 北京科技大学 | A kind of efficient single-mouth refining furnace |
| CN209260138U (en) * | 2018-12-20 | 2019-08-16 | 中冶京诚工程技术有限公司 | Ladle and ferroalloy vacuum refining system for the refining of ferroalloy circulating vacuum |
-
2018
- 2018-12-20 CN CN201811560888.9A patent/CN109439848B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0589443U (en) * | 1992-05-12 | 1993-12-07 | 新日本製鐵株式会社 | Immersion pipe for molten steel treatment |
| JP2000119730A (en) * | 1998-10-08 | 2000-04-25 | Nippon Steel Corp | Method for refining molten steel under reduced pressure |
| CN105624438A (en) * | 2016-02-02 | 2016-06-01 | 镇远县鸿丰新材料有限公司 | Method for refining low-carbon ferromanganese alloy through poor-manganese slag |
| CN207958424U (en) * | 2018-02-06 | 2018-10-12 | 北京科技大学 | A kind of efficient single-mouth refining furnace |
| CN209260138U (en) * | 2018-12-20 | 2019-08-16 | 中冶京诚工程技术有限公司 | Ladle and ferroalloy vacuum refining system for the refining of ferroalloy circulating vacuum |
Non-Patent Citations (1)
| Title |
|---|
| 章俊 ; 王振 ; 方孝红 ; 张旭 ; .长短腿RH精炼炉用于替代摇包冶炼铁合金的新方法.铁合金.2016,(06),1-5. * |
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