CN109694932A - The pre- dephosphorization technology directly supplied oxygen in molten iron - Google Patents
The pre- dephosphorization technology directly supplied oxygen in molten iron Download PDFInfo
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- CN109694932A CN109694932A CN201910096541.1A CN201910096541A CN109694932A CN 109694932 A CN109694932 A CN 109694932A CN 201910096541 A CN201910096541 A CN 201910096541A CN 109694932 A CN109694932 A CN 109694932A
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- molten iron
- dephosphorization
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- oxygen
- oxidizing gas
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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
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/02—Dephosphorising or desulfurising
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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
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/02—Dephosphorising or desulfurising
- C21C1/025—Agents used for dephosphorising or desulfurising
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- Engineering & Computer Science (AREA)
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- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
Abstract
The invention discloses the pre- dephosphorization technologies directly supplied oxygen in molten iron; the following steps are included: oxidizing gas is sprayed into molten iron container at the top of molten iron by top air supply device; oxidizing gas is blown into molten iron container from molten iron bottom by bottom-blowing air feed element; coolant and part dephosphorization material are added from top feed bin by auxiliary addition element, protective gas is first blown before oxidizing gas.The present invention is dephosphorization furnace or the independent pre- dephosphorization station of design by the way that traditional converter is transformed, it realizes and realizes the pre- dephosphorization of molten iron in molten iron container, existing oxygen coverter arrangement and organization of production are not influenced, mitigate oxygen coverter and produces pressure, improve its operating rate, oxidant and the coolant utilization rate for solving pre- dephosphorizing process are low, dephosphorization effect is unstable and influences normal organization of production and production capacity Upgrade Problem, oxidant, coolant, the slag material consumption of subsequent decarbonizing furnace are reduced, conducive to the popularization of the new processes, new technology such as Low-phosphorus Steel, alloy direct-reductionization.
Description
Technical field
The present invention relates to the processing technology field of molten iron harmful element more particularly to it is a kind of directly supplied oxygen in molten iron it is pre-
Dephosphorization technology.
Background technique
Phosphorus is harmful element in most steel grades.With the rapid development of science and technology, market to the high quality of steel,
The requirement of low cost is higher and higher, such as: cryogenic steel, marine steel, anti-hydrogen induced cracking steel and part slab steel, in addition to requiring
Other than sulfur content is extremely low, phosphorus content in steel is also required to be lower than 0.01% or 0.005%；In order to reduce the production of oxygen converter steelmaking
Cost carries out less-slag melting and alloy direct-reduction technique, also requires molten iron phosphorus content lower than 0.020%.In addition, in iron ore
In the case where resource growing tension, import mineral resources is depended on unduly, must bring unfavorable shadow to the long-run development of China's steel and iron industry
It rings, how to develop and use the explored high-phosphorus iron ore in China is the important topic that China's steel industry faces.
Stablize and the pre- dephosphorization technology of efficient molten iron, is that converter realizes that low cost is smelted and low-phosphorous, ultra-low phosphoretic steel produces most
Effective way.
The dephosphorization technology of the prior art is Dephosphorising agent to be added in various ways in molten iron or molten iron surface, is allowed to and iron
Phosphorus in water generates phosphorus compound, so that phosphorus be made to be fixed in slag or enter gas phase to reach pre- dephosphorization purpose.For will be in molten iron
Phosphorus ligands, it is necessary to be allowed to react with Dephosphorising agent and generate stable compound and separated from molten iron.It is taken off according to different
Required different oxygen positions, Dephosphorising agent can be divided into dephosphorization under oxidizing atmosphere agent and dephosphorization under reducing atmosphere agent two in phosphorus reaction product and reaction process
Major class, dephosphorization under reducing atmosphere agent are mainly used for the dephosphorization of ferroalloy and steel alloy；Common dephosphorization under oxidizing atmosphere agent is the oxygen by being easily reduced
Compound dephosphorization agent of the compositions such as agent, basic anhydride and fluxing agent, such as soda system Dephosphorising agent, lime Dephosphorising agent etc..
Molten iron dephosphorization agent is mainly made of oxidant, slag former and fluxing agent.The effect of oxidant is to supply oxygen, by molten iron
In phosphorus oxygen be melted into P2O5, and be combined into phosphate with slag former and stay in dephosphorized slag, normally gaseous oxidant (mainly O2
Or CO2) and solid oxidizer (mill scale, iron ore, sinter return fine, manganese ore etc.)；There are two main classes for slag former: soda
(Na2CO3) system and lime (CaO) system, play a part of solidifying silicon, phosphorous oxides, forms stable silicate or phosphate；It helps
Flux is generally fluorite and calcium chloride etc., for reducing dephosphorization slag melting point, improving the mobile performance of dephosphorized slag, while intensifying dephosphorization
Dephosphorization effect is strengthened in reaction.
To solve the smelting of high phosphorus hot metal and realizing the steady production of Low-phosphorus Steel, the country is turned using duplex technology arrangement dephosphorization
Furnace or by the way of platform aperture realizes the pre- dephosphorization of molten iron.It has a defect that, since oxygen, sinter, ore etc. aoxidize
The utilization rate of the curing agent such as agent and lime, soda is not high, haves the shortcomings that dephosphorization rate is low, dephosphorization efficiency is unstable, causes simultaneously
The oxidation ratio of carbon is high, subsequent decarbonizing furnace shortage of heat, and part ferrosilicon, silicon carbide or aluminium carbon ball etc. need to be added as heating material
Material, and the normal organization of production of conventional converter is influenced, limitation steel making working procedure production capacity is promoted.
The deficiencies of unstable, carbon-drop rate is high, organization of production difficulty is big since there are dephosphorization efficiency, the existing pre- dephosphorization work of molten iron
Skill is not widely popularized always.
Summary of the invention
It is an object of the invention to overcome drawbacks described above existing in the prior art, one kind is provided and is directly supplied oxygen in molten iron
Pre- dephosphorization technology；The present invention is laid out according to fashion of feeding molten iron and workshop, is dephosphorization furnace by the way that traditional converter is transformed, or design independent
Pre- dephosphorization station, the pre- dephosphorization of molten iron can also be realized in the molten iron container such as blast furnace iron outlet groove, ladle, fish torpedo ladle, mixed iron blast,
Existing oxygen coverter arrangement and organization of production are not influenced, are mitigated oxygen coverter and are produced pressure, improve its operating rate.The present invention is by iron
The generalities of the pre- dephosphorization of water, oxidant and the coolant utilization rate for solving pre- dephosphorizing process are low, dephosphorization effect is unstable, influence just
The problems such as normal organization of production and production capacity are promoted.By pre- dephosphorization stabilised efficiency in 80% or more, pre- dephosphorizing process molten iron carbon loss
Less than 0.5%, oxidant, coolant, the slag material consumption of subsequent decarbonizing furnace are reduced, is Low-phosphorus Steel, alloy direct-reductionization etc.
The smooth popularization of new process, new technology provides technical guarantee.
The technical scheme adopted by the invention to solve the technical problem is that:
A kind of pre- dephosphorization technology directly supplied oxygen in molten iron, comprising the following steps:
Oxidizing gas is sprayed into molten iron container at the top of molten iron by top air supply device, it will by bottom-blowing air feed element
Oxidizing gas is blown into molten iron container from molten iron bottom, adds coolant from top feed bin by auxiliary addition element and part is de-
Phosphate material is first blown protective gas before oxidizing gas.
The coolant includes partially sintering mine, lump ore, iron scale；The dephosphorization material and coolant by continuous
The mode for feeding intake or being fed in batches is added.
The oxidizing gas that molten iron is sprayed at the top of molten iron is oxygen, the oxidation that molten iron is blown into from molten iron bottom
Property gas be CO2, the protective gas is using nitrogen, argon gas or CO2。
Dephosphorization material is directly added into fill iron container before pre- dephosphorization technology tapping or during tapping, or passes through blowing
The direct injection dephosphorization material of system.
The dephosphorization material includes lime stone system Dephosphorising agent, lime Dephosphorising agent；Utilize wherein CaCO3Decompose the CO generated2
The oxidation for directly participating in Si, P element, decomposes the CaO of generation as slag making raw material；Lime stone system Dephosphorising agent, lime are de-
Phosphorus agent is with " CaO-CaF2Or CaO-CaCl2" based on powdery or blocky Dephosphorising agent, wherein the granularity of powdery Dephosphorising agent is less than spray
Mouth internal diameter avoids spray gun from blocking, and Dephosphorising agent granularity is less than 1mm；Blocky Dephosphorising agent is with addition of blocky lime stone, lime, fluorite；Two kinds
In Dephosphorising agent, each raw material is as follows with addition of ratio:
Lime stone system Dephosphorising agent: CaF2/CaCO3≥0.1；Lime Dephosphorising agent: CaF2/CaO≥0.13。
The top air supply device, bottom-blowing air feed element, auxiliary addition element use submerged lance, the immersion spray
Rifle is supplied respectively using double medium entirety spray guns or two sets of independent spray guns, and two sets of independent spray guns include that a set of spray gun blows oxidisability
Gas, another set of spray gun blow protective gas and Dephosphorising agent.
Double medium entirety spray guns include gun body, oxidizing gas pipeline, protective gas pipeline, spray gun gas chamber,
The front end of gas chamber is connect by stainless steel tube with oxidizing gas main line with oxidizing gas piping connection, rear end, protectiveness
Gas piping and the protective gas main line of rear end, Dephosphorising agent distributor box connect, the oxidizing gas pipeline, protectiveness gas
Body pipeline, spray gun gas chamber are sleeved on the inside of gun body, are respectively equipped with out on the oxidizing gas pipeline, protective gas pipeline
Closing valve；
Protective gas pipeline uses stainless steel tube or seamless pipe, and the part that oxidizing gas pipeline is contacted with molten iron uses
It is made of high-temperature refractory；
Oxidizing gas pipeline front end is zirconium matter or other high-temperature refractory hollow pipes, at rear end to spray gun gas chamber
For stainless steel tube, it is connected with air supply header road, is closely connected between zirconium matter hollow pipe and stainless steel tube with casing.
The double medium entirety spray guns in bottom-blowing air feed element, that is, bottom further include bottom blowing nozzle, and bottom blowing nozzle is mounted on same
Brick cup is mounted on different brick cups, and oxidizing gas pipeline, protective gas pipeline, spray gun gas chamber are mounted on molten iron appearance
The bottom end or side of device；Brick cup is arranged in entire or half of molten iron container bottom.
Bottom-blowing air feed element uses CO2, protective gas controlled by two sets independent air supply systems, two kinds of gas mediums
It is mixed by setting ratio, enters air supply device through Dephosphorising agent distributor box.
Top spray oxygen supply intensity Q is less than 50%, L/L of corresponding conventional converter oxygen supply intensity0Less than 0.25, wherein L is molten bath
Impact depth, L0For pool depth, and according to Q, L/L0It is worth and determines oxygen rifle height；When top spray oxygen, bottom blowing protective gas
Air supply intensity is greater than 0.01Nm3/ min.t, using CO2For bottom blowing medium, top blowing oxygen automatically switches to nitrogen, argon gas after closing；By
Process conditions limitation, if can only top injecting oxygen, bottom blowing inert gas air supply intensity should be greater than 0.05Nm3/min.t, pushes up storehouse
Cooperation blowing powdery dephosphorization material while adding dephosphorization material.
The beneficial effects of the present invention are:
It is dephosphorization furnace by the way that traditional converter is transformed, or design only 1. the present invention can be laid out according to fashion of feeding molten iron and workshop
Vertical pre- dephosphorization station can also realize that molten iron is pre- de- in the molten iron container such as blast furnace iron outlet groove, ladle, fish torpedo ladle, mixed iron blast
Phosphorus does not influence existing oxygen coverter arrangement and organization of production, mitigates oxygen coverter and produce pressure, improve its operating rate, the present invention
Pre- dephosphorization is high-efficient, carbon loss can be stablized in 80% or more, pre- dephosphorizing process molten iron less than 0.5%, reduce subsequent de-
Oxidant, coolant, slag material consumption and the cost of carbon furnace, are the new processes such as Low-phosphorus Steel, alloy direct-reductionization, new technology
It smoothly promotes and technical guarantee is provided.Oxidant and the coolant utilization rate for solving pre- dephosphorizing process are low, dephosphorization effect is unstable,
The problem of influencing normal organization of production and production capacity promotion.
2, the present invention solves the utilization rate due to the curing agent such as the oxidants such as oxygen, sinter, ore and lime, soda
It is not high, have the shortcomings that dephosphorization rate is low, dephosphorization efficiency is unstable, while causing the oxidation ratio of carbon high, subsequent decarbonizing furnace heat
Deficiency need to be added part ferrosilicon, silicon carbide or aluminium carbon ball etc. as heating material, and influence the normal production group of conventional converter
It knits, limitation steel making working procedure production capacity is promoted and problem at high cost.
3. the present invention is supplied by the way that oxidizing gas is sprayed into molten iron at the top of molten iron by top air supply device by bottom blowing
Oxidizing gas is blown into molten iron from molten iron bottom by gas element, adds coolant and portion from top feed bin by auxiliary addition element
Divide dephosphorization material.It pushes up storehouse and the ratio of coolant and injection dephosphorization agent is added according to practical iron water amount, molten iron condition, pre- dephosphorization effect
Fruit, blowing ability etc. determine, and according to the thermal balance of dephosphorizing process, calculate coolant and Dephosphorising agent additional amount, pass through the mould that feeds
Type automatically controls additional amount, under the premise of sufficiently meeting technique and requiring, can be effectively reduced coolant and injection dephosphorization agent
Usage amount reduces production cost.
4. coolant of the invention uses sinter, lump ore, iron scale, the addition for stating dephosphorization material and coolant is used
The mode of continuous dosing or fed batch guarantees that dephosphorisation reaction is steady, prevents clinker conglomeration.By adding part from top feed bin
The coolants such as sinter, lump ore, iron scale and part dephosphorization material can be conveniently adjusted molten iron temperature, mitigate fire proofed wood
Material corrodes, stablizes dephosphorized slag index, by the way that into molten iron, directly oxygen supply and injection dephosphorization agent can be improved dephosphorization efficiency, solve due to
The contradiction of the limited technique requirement for being unable to satisfy the control for the treatment of process temperature and dephosphorization slag making of blowing amount.
5. the oxidizing gas that the present invention sprays into molten iron at the top of molten iron is oxygen or CO2, the protective gas is used
Nitrogen, argon gas.Oxygen is directly sprayed into molten iron using submerged lance, is directly blown into molten iron using bottom-blown air brick
CO2 improves oxidizing gas utilization rate, increases the contact probability of Si, P in oxygen element and molten iron, promote to generate SiO2 and
P2O5 reduces gas consumption, stablizes dephosphorization efficiency, reduces carbon oxidation in preprocessing process.
6. dephosphorization material is directly added before pre- dephosphorization technology tapping or during tapping in the present invention into fill iron container, or
By the direct injection dephosphorization material of injection system, the dephosphorization material includes lime stone system Dephosphorising agent, lime Dephosphorising agent, is utilized
CaCO3Decompose the CO generated2The oxidation for directly participating in Si, P element, decomposes the CaO of generation as slag making raw material；According to blowing
Mode, gas medium can be the protectiveness such as nitrogen, argon, can also use CO2As blowing media；It is lower than 1350 DEG C to generate fusing point
Dephosphorized slag, according to " CaO-SiO2-CaF2" ternary phase diagrams, lime stone system Dephosphorising agent, lime Dephosphorising agent are with " CaO-
CaF2Or CaO-CaCl2" based on powdery or blocky Dephosphorising agent, wherein the granularity of powdery Dephosphorising agent is avoided less than nozzle pluggage
Spray gun blocking is typically designed Dephosphorising agent granularity less than 1mm；Blocky Dephosphorising agent be require in proportion with addition of blocky lime stone, lime,
Fluorite.In two kinds of Dephosphorising agents, each raw material is as follows with addition of ratio: lime stone system Dephosphorising agent: CaF2/CaCO3≥0.1；Lime
Dephosphorising agent: CaF2/CaO≥0.13.Process costs are reduced, process product quality is improved.
7. protective gas of the invention uses nitrogen, argon gas or CO2, oxidizing gas pipeline is automatically performed gas and cuts
It changes and regulatory function, opens gas process: " dephosphorization is strengthened in protective gas stirring → oxygen blast dephosphorization → protective gas stirring "；Injection dephosphorization
Agent pipeline opens gas process: " dephosphorization is strengthened in protective gas stirring → injection dephosphorization agent → protective gas stirring " can guarantee: 1. oxygen
Solid/liquid/gas reactions area temperature guarantees nozzle or air brick.2. spraying into powdery Dephosphorising agent by technique requirement to protect gas as medium.3. shape
At dynamic atmosphere, reaction between carbon and oxygen is reduced, avoids CO that discharge is concentrated to cause to turn over greatly.4. inhibiting foamed clinker.5. preventing gas supply member
Part blocking.After 6. oxygen-supplying amount reaches technique initialization, continues to be blown into protective gas and dephosphorized slag is promoted to react with molten iron, reinforcing dephosphorization.
8. state top air supply device, bottom-blowing air feed element, auxiliary addition element of the invention is submerged lance, described double
Medium entirety spray gun includes oxidizing gas pipeline, protective gas pipeline, spray gun gas chamber, the front end of gas chamber and oxidizing gas
Piping connection, rear end and oxidizing gas main line connect, and the protective gas main line of protective gas pipeline and rear end connects
It connects, is respectively equipped with controlled valve on the oxidizing gas pipeline, protective gas pipeline.Controlled valve realizes gas supply mechanism
" gas " handoff functionality makes molten iron be in flow regime for the protective gas such as nitrogen-blow, argon gas before oxidizing gas, prevents
Only air supply device blocking or local vigorous reaction cause molten iron to turn over greatly.Wherein oxygen pipeline is into molten iron directly for O2, protectiveness
Gas piping passes through protective gas injection dephosphorization agent into molten iron.O2It is reacted with Si and generates SiO2,SiO2It is generated with Dephosphorising agent low
Fusing point dephosphorized slag, and P2O5It is combined into stable phosphate.The submerged lance is only using double medium entirety spray guns or two sets
Vertical spray gun supplies respectively, and two sets of independent spray guns include that a set of spray gun blows oxidizing gas, another set of spray gun blow protective gas and
Dephosphorising agent, can be conveniently adjusted and control the straying quatity of gas with various and component, guarantee process product quality, reduce process at
This.
9. being connect since protective gas pipeline uses stainless steel tube or seamless pipe with Dephosphorising agent distributor box；Oxidisability gas
The part that body pipeline is contacted with molten iron avoids oxygen supply process metal tube scaling loss using making of high-temperature refractory.Protectiveness gas
The air supply device quantity of body and oxidizing gas, arrangement, air supply intensity, Dephosphorising agent injecting velocity, blowing amount etc. are according to molten iron item
Part, pretreating effect, process cycle setting, the air supply intensity of protective gas are generally higher than 3 times of oxidizing gas intensity, benefit
Oxygen reaction zone temperature is reduced with the diffusion of protective gas, improves the service life of spray gun and air brick core.
10. since the double medium entirety spray guns in bottom-blowing air feed element, that is, bottom further include bottom blowing nozzle, the installation of bottom blowing nozzle
In same brick cup or it is mounted on different brick cups.Bottom blowing nozzle is arranged in dedicated bottom blowing brick cup, oxidizing gas pipe
Road, protective gas pipeline, spray gun gas chamber are mounted on the bottom end or side of molten iron container.The distribution of brick cup according to processing needs,
It generally uniform can be arranged in entire or half of molten iron container bottom, and brick cup quantity, knot are designed according to container shapes and treating capacity
Structure is compact, convenient for arrangement, reduces manufacture and use maintenance cost；Guarantor is blown by medium bottom blowing brick cups double before being blended into molten iron
Shield property gas, when processing, are switched to oxygen blast and injection dephosphorization agent, avoid spray nozzle clogging.
11. the present invention uses CO by bottom-blowing air feed element2, protective gas pass through two sets of independent air supply systems respectively
Control, two kinds of gas mediums are mixed by setting ratio, enter air supply device through Dephosphorising agent distributor box.According to preprocessed molten iron amount,
Hot metal composition, molten iron temperature, pretreatment time etc. adjust CO2Air supply intensity, gas supply ratio with protective gas, air supply device
Quantity, distribution according to powder granularity, blowing amount, pretreating effect design.It is blown by spray gun and bottom-blowing air feed element
CO2, it is reacted with the C in molten iron and generates CO, the dynamic conditions that mixing effect can be improved, improve dephosphorization.
12 top blast oxygen supply intensity Q of the present invention should be less than 50%, L/L of corresponding conventional converter oxygen supply intensity0Less than 0.25, and
According to Q, L/L0It is worth and determines oxygen rifle height.L is the impact depth in molten bath, L0For pool depth, decarbonization rate can be delayed, realized
The purpose of " dephosphorization guarantor carbon "；Position, design specialized dephosphorization oxygen lance, the hole count of dephosphorization oxygen lance, hole are pre-processed in dephosphorization converter, molten iron
Diameter and oxygen flow are designed according to pretreating effect, molten iron container, pre-processing period etc..When top blast oxygen, bottom blowing protectiveness gas
The air supply intensity of body is greater than 0.01Nm3/ min.t, or use CO2For bottom blowing medium, CO is utilized2Decomposition improve melting bath stirring effect
Fruit improves dephosphorization efficiency, and top blowing oxygen automatically switches to the protective gas such as nitrogen, argon gas after closing.
13. limited by process conditions, if can only top injecting oxygen, bottom blowing inert gas air supply intensity should be greater than
0.05Nm3/min.t, cooperation blowing powdery dephosphorization material while top storehouse adds dephosphorization material can reach higher dephosphorization effect
Rate.
Detailed description of the invention
Fig. 1 is impact depth L and pool depth L0Schematic diagram.
Fig. 2 is CaO-2CaOSiO2-CaF2 ternary phase diagrams.
Fig. 3 is the structural schematic diagram of double medium spray guns and bottom blowing gas-feeding brick core.
Fig. 4 is the left view of Fig. 3.
Specific embodiment
Technical solution in order to enable those skilled in the art to better understand the present invention, below in conjunction with of the invention real
The attached drawing in example is applied, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described implementation
Example is only a part of the embodiment of the present invention, instead of all the embodiments.
In conjunction with Fig. 1-Fig. 4, a kind of pre- dephosphorization technology directly supplied oxygen in molten iron, comprising the following steps:
By top air supply device oxidizing gas is sprayed into molten iron at the top of molten iron, will be aoxidized by bottom-blowing air feed element
Property gas from molten iron bottom be blown into molten iron, coolant and part dephosphorization material are added from top feed bin by auxiliary addition element.
The ratio that coolant and injection dephosphorization agent is added in storehouse is pushed up, according to practical iron water amount, molten iron condition, pre- dephosphorization effect, blowing ability
Deng determination, and according to the thermal balance of dephosphorizing process, coolant and Dephosphorising agent additional amount are calculated, is automatically controlled and is added by charging model
Enter amount.
The coolant includes partially sintering mine, lump ore, iron scale.
The addition of the dephosphorization material and coolant guarantees that dephosphorisation reaction is flat by the way of continuous dosing or fed batch
Surely, clinker conglomeration is prevented.
By partially sintering the coolants such as mine, lump ore, iron scale and part dephosphorization material from the addition of top feed bin, to adjust
Molten iron temperature is saved, mitigates refractory material erosion, stablize dephosphorized slag index, by the way that directly oxygen supply and injection dephosphorization agent can into molten iron
Dephosphorization efficiency is improved, solves to be limited what the technique for being unable to satisfy the control for the treatment of process temperature and dephosphorization slag making required due to blowing amount
Contradiction.The ratio for pushing up storehouse addition and injection dephosphorization agent, according to practical iron water amount, molten iron condition, pre- dephosphorization effect, blowing ability etc.
It determines, and according to the thermal balance of dephosphorizing process, calculates coolant and Dephosphorising agent additional amount, automatically controlled by charging model.
The oxidizing gas that molten iron is sprayed at the top of molten iron is oxygen, the oxidation that molten iron is blown into from molten iron bottom
Property gas be CO2.Oxygen is directly sprayed into molten iron using submerged lance, is directly blown into molten iron using bottom-blown air brick
CO2, oxidizing gas utilization rate is improved, the contact probability of Si, P in oxygen element and molten iron are increased, promotes to generate SiO2With
P2O5, gas consumption is reduced, dephosphorization efficiency is stablized, reduces carbon oxidation in preprocessing process.
Dephosphorising agent is directly added before pre- dephosphorization technology tapping or during tapping into fill iron container, or passes through blowing system
It unites direct injection dephosphorization agent.It is generally lime stone system Dephosphorising agent with Dephosphorising agent under the conditions of this, can also be lime Dephosphorising agent, benefit
Use CaCO3Decompose the CO generated2The oxidation for directly participating in Si, P element, decomposes the CaO of generation as slag making raw material；According to spray
The mode blown, gas medium can be the protectiveness such as nitrogen, argon, can also use CO2As blowing media.
The Dephosphorising agent includes lime stone system Dephosphorising agent, lime Dephosphorising agent.Utilize CaCO3Decompose the CO generated2Directly join
With the oxidation of Si, P element, the CaO of generation is decomposed as slag making raw material；According to the mode of blowing, gas medium can be nitrogen, argon
Etc. protectiveness, CO can also be used2As blowing media.
To generate the dephosphorized slag that fusing point is lower than 1350 DEG C, according to " CaO-SiO2-CaF2" ternary phase diagrams, the lime stone system
Dephosphorising agent, lime Dephosphorising agent are with " CaO-CaF2Or CaO-CaCl2" based on powdery or blocky Dephosphorising agent, wherein powdery is de-
The granularity of phosphorus agent is less than nozzle pluggage and spray gun is avoided to block, and is typically designed Dephosphorising agent granularity less than 1mm；Blocky Dephosphorising agent be by than
Example is required with addition of blocky lime stone, lime, fluorite.In two kinds of Dephosphorising agents, each raw material is as follows with addition of ratio:
Lime stone system Dephosphorising agent: CaF2/CaCO3≥0.1。
Lime Dephosphorising agent: CaF2/CaO≥0.13。
The protective gas uses nitrogen, argon gas or CO2.The effect of protective gas includes: 1. oxygen reaction zone temperature
Degree guarantees nozzle or air brick.2. spraying into powdery Dephosphorising agent by technique requirement to protect gas as medium.3. dynamic atmosphere is formed,
Reaction between carbon and oxygen is reduced, avoids CO that discharge is concentrated to cause to turn over greatly.4. inhibiting foamed clinker.5. preventing air supply device from blocking.6. supplying
After oxygen amount reaches technique initialization, continues to be blown into protective gas and dephosphorized slag is promoted to react with molten iron, reinforcing dephosphorization.
Oxidizing gas pipeline is automatically performed gas switching and regulatory function, opens gas process: " protective gas stirring → oxygen blast
Dephosphorization is strengthened in dephosphorization → protective gas stirring "；Injection dephosphorization agent pipeline opens gas process: " protective gas stirring → injection dephosphorization agent
Dephosphorization is strengthened in the stirring of → protective gas ".
The top air supply device, bottom-blowing air feed element, auxiliary addition element are submerged lance, and submerged lance is general
For single Analysis of Nested Design.According to pretreatment amount, processing the time, oxygen supply intensity require design spray gun outer diameter, gas supply pipe diameter sum number amount,
Length etc. is immersed, leads to the caliber of protective gas pipeline, quantity should be realized according to powder granularity and the design of blowing amount and stablize, be fast
Fast dephosphorization.
The submerged lance can also be used two sets of independent spray guns and supplied respectively using double medium entirety spray guns, i.e., a set of
Spray gun oxygen blast, another set of spray gun blow protective gas and Dephosphorising agent.
Double medium entirety spray guns include gun body 1, oxidizing gas pipeline 3, protective gas pipeline 2, spray gun gas
Room 4, the front end of gas chamber 4 is connect with oxidizing gas pipeline 3, rear end is connect by stainless steel tube 5 with oxidizing gas main line,
Protective gas pipeline 2 is connect with the protective gas main line of rear end, Dephosphorising agent distributor box, the oxidizing gas pipeline 3,
Protective gas pipeline 2, spray gun gas chamber 4 are sleeved on 1 inside of gun body, therefore 2 pipeline of protective gas pipeline needs injection dephosphorization
Agent, caliber are relatively large.Controlled valve is respectively equipped on the oxidizing gas pipeline, protective gas pipeline.Controlled valve
Realize that " gas " handoff functionality of gas supply mechanism makes at molten iron for the protective gas such as nitrogen-blow, argon gas before oxidizing gas
In flow regime, prevent air supply device blocking or local vigorous reaction from molten iron being caused to turn over greatly.Wherein oxygen pipeline is straight into molten iron
It connects for O2, protective gas pipeline pass through protective gas injection dephosphorization agent into molten iron.O2It is reacted with Si and generates SiO2,SiO2
Low melting point dephosphorized slag, and P are generated with Dephosphorising agent2O5It is combined into stable phosphate.
Protective gas pipeline uses stainless steel tube or seamless pipe, connect with Dephosphorising agent distributor box；Oxidizing gas pipeline
The part contacted with molten iron avoids oxygen supply process metal tube scaling loss using making of high-temperature refractory.Protective gas and oxygen
The property the changed air supply device quantity of gas, arrangement, air supply intensity, Dephosphorising agent injecting velocity, blowing amount etc. are according to molten iron condition, pre- place
Effect, process cycle setting are managed, the air supply intensity of protective gas is generally higher than 3 times of oxidizing gas intensity, utilizes protection
Property gas diffusion reduce oxygen reaction zone temperature, improve spray gun and air brick core service life.
3 front end of oxidizing gas pipeline is zirconium matter or other high-temperature refractory hollow pipes 31, and process can also
It is substituted with hard solid tubes, baking process hard material is melted and cleaned out；Rear end (to spray gun gas chamber) is stainless steel tube
33, it is connected with air supply header road, is closely connected between zirconium matter hollow pipe and stainless steel tube with casing 32.Oxygen pipeline and protection gas
The pipeline of body can be to be one or more, and if more, spray gun bottom end is typically provided spray gun gas chamber, to stabilizing gas pressure,
Tail end supplies main line with it and is connected.Spray gun of the invention is longer, related with immersion depth, processing station integral layout, and bottom
Blow that air supply brick core is shorter, it is related with the resistance to material of fill iron container and steel construction thickness, service life etc..
The double medium entirety spray guns in bottom-blowing air feed element, that is, bottom further include bottom blowing nozzle, and bottom blowing nozzle is arranged dedicated
Bottom blowing brick cup, oxidizing gas pipeline, protective gas pipeline, spray gun gas chamber are mounted on the bottom end or side of molten iron container.Seat
The distribution of brick generally uniform can be arranged in entire or half of molten iron container bottom according to processing needs, and according to container shapes and
Treating capacity designs brick cup quantity.To avoid spray nozzle clogging, double medium bottom blowing brick cups are blown protective gas before being blended into molten iron, locate
Oxygen blast and injection dephosphorization agent are switched to when reason.
Bottom blowing nozzle is mountable in same brick cup, also respectively can be on different brick cups.
Bottom-blowing air feed element can use CO2, protective gas pass through two sets of independent air supply systems controls respectively, two kinds
Gas medium is mixed by setting ratio, enters air supply device through Dephosphorising agent distributor box.According to preprocessed molten iron amount, hot metal composition,
Molten iron temperature, pretreatment time etc. adjust CO2Air supply intensity, gas supply ratio with protective gas, the quantity of air supply device are divided
Cloth is designed according to powder granularity, blowing amount, pretreating effect.The CO being blown by spray gun and bottom-blowing air feed element2, in molten iron
C reaction generate CO, can improve mixing effect, improve dephosphorization dynamic conditions.
To delay decarbonization rate, reach the treatment principle of " dephosphorization guarantor carbon ", top spray oxygen supply intensity Q should be less than corresponding conventional and turn
50%, L/L of furnace oxygen supply intensity0Less than 0.25, and according to Q, L/L0It is worth and determines oxygen rifle height.L is the impact depth in molten bath, L0
For pool depth.Position, design specialized dephosphorization oxygen lance, hole count, aperture and the oxygen of dephosphorization oxygen lance are pre-processed in dephosphorization converter, molten iron
Flow is designed according to pretreating effect, molten iron container, pre-processing period etc..When top spray oxygen, the gas supply of bottom blowing protective gas
Intensity is greater than 0.01Nm3/ min.t, or use CO2For bottom blowing medium, CO is utilized2Decomposition improve melting bath stirring effect, improve it is de-
Phosphorus efficiency, top spray oxygen automatically switch to the protective gas such as nitrogen, argon gas after closing.It is limited by process conditions, if can only top
Injecting oxygen, bottom blowing inert gas air supply intensity should be greater than 0.05Nm3/min.t.To reach higher dephosphorization efficiency, top storehouse adds
While dephosphorization material, cooperation blowing powdery dephosphorization material.
Under the low air supply intensity of the present invention, the reaction between carbon and oxygen intensity of preprocessing process is low, and fugitive dust is few, the feature of environmental protection is good, to processing
Process still has a small amount of fugitive dust, can be less than 10mg by design bag filter, guarantee dust emission concentration.
Based on the embodiments of the present invention, those of ordinary skill in the art are obtained without making creative work
The every other embodiment obtained, should fall within the scope of the present invention.
Claims (10)
1. a kind of pre- dephosphorization technology directly supplied oxygen in molten iron, characterized in that the following steps are included:
By top air supply device oxidizing gas is sprayed into molten iron container at the top of molten iron, will be aoxidized by bottom-blowing air feed element
Property gas from molten iron bottom be blown into molten iron container, coolant and part dephosphorization material are added from top feed bin by auxiliary addition element
Material, is first blown protective gas before oxidizing gas.
2. the pre- dephosphorization technology directly supplied oxygen in molten iron as described in claim 1, characterized in that the coolant includes portion
Divide sinter, lump ore, iron scale；The dephosphorization material and coolant by continuous dosing or are fed in batches addition.
3. the pre- dephosphorization technology directly supplied oxygen in molten iron as described in claim 1, characterized in that described to be sprayed at the top of molten iron
The oxidizing gas for entering molten iron is oxygen, and the oxidizing gas for being blown into molten iron from molten iron bottom is CO2, the protectiveness gas
Body uses nitrogen, argon gas or CO2。
4. the pre- dephosphorization technology directly supplied oxygen in molten iron as described in claim 1, characterized in that in pre- dephosphorization technology tapping
Dephosphorization material is directly added during preceding or tapping into fill iron container, or passes through the direct injection dephosphorization material of injection system.
5. the pre- dephosphorization technology directly supplied oxygen in molten iron as claimed in claim 4, characterized in that the dephosphorization material includes
Lime stone system Dephosphorising agent, lime Dephosphorising agent；Utilize wherein CaCO3Decompose the CO generated2The oxidation of Si, P element are directly participated in,
The CaO generated is decomposed as slag making raw material；Lime stone system Dephosphorising agent, lime Dephosphorising agent are with " CaO-CaF2Or CaO-
CaCl2" based on powdery or blocky Dephosphorising agent, wherein the granularity of powdery Dephosphorising agent is less than nozzle pluggage spray gun is avoided to block,
Dephosphorising agent granularity is less than 1mm；Blocky Dephosphorising agent is with addition of blocky lime stone, lime, fluorite；In two kinds of Dephosphorising agents, each raw material with addition of
Ratio is as follows:
Lime stone system Dephosphorising agent: CaF2/CaCO3≥0.1；Lime Dephosphorising agent: CaF2/CaO≥0.13。
6. the pre- dephosphorization technology directly supplied oxygen in molten iron as described in claim 1, characterized in that the top gas supply member
Part, bottom-blowing air feed element, auxiliary addition element use submerged lance, the submerged lance using double medium entirety spray guns or
Two sets of independent spray guns of person supply respectively, and two sets of independent spray guns include that a set of spray gun blows oxidizing gas, and another set of spray gun blows protection
Property gas and Dephosphorising agent.
7. the pre- dephosphorization technology directly supplied oxygen in molten iron as claimed in claim 6, characterized in that double media integrally spray
Rifle includes gun body, oxidizing gas pipeline, protective gas pipeline, spray gun gas chamber, front end and the oxidizing gas pipe of gas chamber
Road connection, rear end are connect by stainless steel tube with oxidizing gas main line, the protectiveness gas of protective gas pipeline and rear end
Body main line, the connection of Dephosphorising agent distributor box, the oxidizing gas pipeline, protective gas pipeline, spray gun gas chamber are sleeved on spray
On the inside of gun body, controlled valve is respectively equipped on the oxidizing gas pipeline, protective gas pipeline；
Protective gas pipeline uses stainless steel tube or seamless pipe, and the part that oxidizing gas pipeline is contacted with molten iron is used with high
Warm refractory material production；
Oxidizing gas pipeline front end is zirconium matter or other high-temperature refractory hollow pipes, is not at rear end to spray gun gas chamber
Become rusty steel pipe, is connected with air supply header road, is closely connected between zirconium matter hollow pipe and stainless steel tube with casing.
8. the pre- dephosphorization technology directly supplied oxygen in molten iron as claimed in claim 7, characterized in that pair of bottom-blowing air feed element
Medium entirety spray gun further includes bottom blowing nozzle, and bottom blowing nozzle is mounted on same brick cup or is mounted on different brick cups, oxygen
The property changed gas piping, protective gas pipeline, spray gun gas chamber are mounted on the bottom end or side of molten iron container；Brick cup is arranged in entirely
Or half of molten iron container bottom.
9. the pre- dephosphorization technology directly supplied oxygen in molten iron as claimed in claim 6, characterized in that bottom-blowing air feed element uses
CO2, protective gas by two sets independent air supply systems controls, two kinds of gas mediums are by setting ratio mixing, through Dephosphorising agent
Distributor box enters air supply device.
10. the pre- dephosphorization technology directly supplied oxygen in molten iron as claimed in claim 3, characterized in that top spray oxygen supply intensity Q is small
In 50%, L/L of corresponding conventional converter oxygen supply intensity0Less than 0.25, wherein L is the impact depth in molten bath, L0For pool depth,
And according to Q, L/L0It is worth and determines oxygen rifle height；When top spray oxygen, the air supply intensity of bottom blowing protective gas is greater than 0.01Nm3/
Min.t, using CO2For bottom blowing medium, top blowing oxygen is switched to nitrogen, argon gas after closing；It is limited by process conditions, if can only top
Injecting oxygen, bottom blowing inert gas air supply intensity should be greater than 0.05Nm3/min.t, while top storehouse adds dephosphorization material, cooperation spray
Blow powdery dephosphorization material.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115232906A (en) * | 2021-04-22 | 2022-10-25 | 石家庄市宏森熔炼铸造有限公司 | Preparation method of low-phosphorus high-purity pig iron |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001200309A (en) * | 2000-01-18 | 2001-07-24 | Sumitomo Metal Ind Ltd | Top blowing oxygen lance for converter and converter refining method |
| CN101880751A (en) * | 2009-05-07 | 2010-11-10 | 营口东邦冶金设备耐材有限公司 | Composite desulfurization/dephosphorization spray gun for molten iron |
| CN102643946A (en) * | 2012-04-24 | 2012-08-22 | 北京科技大学 | Converter steelmaking method through power injection dephosphorization by adopting supersonic speed oxygen lance and supersonic speed oxygen lance |
| CN104480251A (en) * | 2014-12-05 | 2015-04-01 | 中冶京诚工程技术有限公司 | Pretreatment device for simultaneously desulfurizing, desiliconizing and dephosphorizing molten iron, and application and smelting method thereof |
| CN106282487A (en) * | 2016-09-13 | 2017-01-04 | 北京北科中钢工程技术有限公司 | A kind of pre-dephosporizing method for molten iron |
| CN106282832A (en) * | 2016-08-06 | 2017-01-04 | 山东泰山钢铁集团有限公司 | Hot-metal bottle dephosphorization, refining furnace and Argon station smelt titaniferous ferritic stainless steel method |
-
2019
- 2019-01-31 CN CN201910096541.1A patent/CN109694932B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001200309A (en) * | 2000-01-18 | 2001-07-24 | Sumitomo Metal Ind Ltd | Top blowing oxygen lance for converter and converter refining method |
| CN101880751A (en) * | 2009-05-07 | 2010-11-10 | 营口东邦冶金设备耐材有限公司 | Composite desulfurization/dephosphorization spray gun for molten iron |
| CN102643946A (en) * | 2012-04-24 | 2012-08-22 | 北京科技大学 | Converter steelmaking method through power injection dephosphorization by adopting supersonic speed oxygen lance and supersonic speed oxygen lance |
| CN104480251A (en) * | 2014-12-05 | 2015-04-01 | 中冶京诚工程技术有限公司 | Pretreatment device for simultaneously desulfurizing, desiliconizing and dephosphorizing molten iron, and application and smelting method thereof |
| CN106282832A (en) * | 2016-08-06 | 2017-01-04 | 山东泰山钢铁集团有限公司 | Hot-metal bottle dephosphorization, refining furnace and Argon station smelt titaniferous ferritic stainless steel method |
| CN106282487A (en) * | 2016-09-13 | 2017-01-04 | 北京北科中钢工程技术有限公司 | A kind of pre-dephosporizing method for molten iron |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115232906A (en) * | 2021-04-22 | 2022-10-25 | 石家庄市宏森熔炼铸造有限公司 | Preparation method of low-phosphorus high-purity pig iron |
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