CN1046562A - The production method of normal steels - Google Patents

Abstract

The production method of the normal steels of recommending is included in melting carbon element work in-process in the steel melting furnace, is injected into ladle, add sweetening material, reductive agent in the ladle and contain alloying element through heat treated oxidation material in advance.At this moment, reductive agent is to add in batches, portion be with sweetening material the carbon element work in-process inject that ladle is no more than that 1/3 Quality Process adds and another deal with before above-mentioned carbon element work in-process have gone out toward ladle, adding through heat treated oxidation material.

Description

The production method of normal steels

The invention belongs to field of metallurgy, more particularly, is the production method about conventional steel grade.

So-called normal steels, we are interpreted as having the steel grade of following composition (quality %):

Carbon-0.05～0.50

Manganese-0.25～2.50

Iron-all the other.

In addition, normal steels also can comprise following composition (quality %):

Silicon-below 0.60

Aluminium-below 0.08

Chromium-below 2.00

Vanadium-below 0.20

Following and other elements of titanium-0.20.

The present invention is applicable to the production of converter, open hearth and electric furnace normal steels.

The production that the present invention is used for manganese steel is the most effective.

At present, in world's practice, outer (as in the ladle) purifying method of the stove of steel obtains broad development, its objective is the quality that improves institute's smelting metal in the steelmaking equipment.

In ladle, molten steel is carried out also will carrying out the purifying treatment of desulfurization, dephosphorization, dehydrogenation, denitrogenation and other element to molten steel alloying and rotten the processing except adding various elements.

The purifying treatment of molten steel, generally do not carry out simultaneously with alloying process, but make these operations carry out successively-at first be to add the various iron alloys that contain alloying element in the ladle to make the molten steel alloying, in molten steel, be blown into various sweetening materials then so that its purification is then carried out vacuum-treat to molten steel again.

Each operation in these operations all is accompanied by thermal losses, therefore, in order to compensate the outer thermal losses of handling of molten steel stove, require or metal is placed on reheat in the steelmaking equipment, oxidisability before molten steel is come out of the stove increases and makes the degradation of steel, or make the specific equipment can in ladle, heat molten steel, certainly, can increase the price of steel like this and for the production of using steel always, be not all to be worthwhile in any case.

With in molten steel, adding howlite concentrate or manganese metal slag as alloying element with to add excellent aluminium produces steel as reductive agent in ladle method (SU, A, 1219654) be well-known.

This method comprises carbon element work in-process and the amputation dross-oxidised that goes out not deoxidation in the ladle.Alloying element is by in the molten steel in the way adding ladle that they are restored from howlite concentrate or manganese metal slag, and will in advance alloying element be solidificated on the aluminium bar before adding ladle.The materials consumption of this method will make the amount that adds aluminium will be higher than by the necessary amount of stoichiometry and select for use.

Existing method can not guarantee the detrimental impurity in the purify hot metal, and especially sulphur so just causes obstacle for the high-quality steel that obtains low sulfur content.

Employing forces club-shaped material and adds the disappearance that alloying element and reductive agent can cause some elements in the way dealing molten steel that inserts molten steel, especially manganese, steel is caused the pollution of external nonmetallic impurity, promptly be left on contain the abandoned mine residue in the alloying element oxidation material composition pollution all these all can make the degradation of steel.

Add bar-shaped reductive agent, can make its scaling loss consumingly because of the result who interacts with airborne oxygen and contact with the eternal ferriferous oxide that can't do without of carbon steel water surface, this will improve the price of steel.

In addition, the preparation work of bar-shaped reductive agent is coated with the oxidation material that last layer contains alloying element on its surface, increase auxiliary expenses, and this can increase the price of steel equally.

The bar that adopts the special steel alloying of making to use, except meeting causes certain technical difficulty aspect its preparation work, storage and use, it also can limit their use range when producing normal steels, in the composition of normal steels, and the content of manganese from 0.5 to 2.0%.

Scribble above the employing aluminium bar that one deck contains the alloying element oxidation material can not guarantee to obtain the steel of the manganese that requires and aluminum chemistry composition, because the scaling loss of reductive agent is not controlled operation, but depending on a series of wayward or complete uncontrollable parameters as the half-finished oxidisability of carbon element before coming out of the stove, the carbon element work in-process are come out of the stove in the process from steel melting furnace and the influence of the back of coming out of the stove by the molten steel surface secondary oxidation etc.

Making the existing method (SU, A, 1044641) of steel alloying with manganese is that everybody is familiar with.It is included in melting carbon element work in-process in the steel melting furnace, and it is put into ladle, will contain alloying element and add molten steel surface in the ladle through heat treated oxidation material with reductive agent and lime in advance.As the low-phosphorous manganese slag in the alloying element people iron alloy production commonly used, reductive agent aluminium then commonly used, the amount of lime should guarantee that the alkalescence of slag is 2.0～3.5.Then to molten steel top blast oxygen 3～30 seconds and blowing argon gas.

But, can not obtain the high-quality steel in this way, because, oxidation material, reductive agent and the lime that will contain alloying element-manganese (the low-phosphorous manganese slag that iron alloy is produced) simultaneously are added to together by the carbon element reolled steel water surface of putting into ladle in the steel melting furnace, then oxygen blast again, can make like this to make the process of steel alloying be difficult to control, and can not guarantee the height desulfurization of molten steel in the ladle with manganese.

Can guarantee to reduce the sulphur content in the steel and use sweetening material when generally in ladle, handling degree of depth deoxidation molten steel, as synthetic refining slag, calcic or contain magnesium material (all being the powder shape usually) etc. and handle the sulphur content that also can reduce in the molten steel.

The prerequisite that also has a deep desulfuration is exactly to increase contacting between sweetening material and the molten steel.This contact can reach by following manner when handling molten steel in ladle, for example, before not tapping, in advance the synthetic slag is put into ladle, like this, in the beginning of tapping in ladle molten steel is mixed tempestuously with synthetic slag.

When using calcic or magniferous sweetening material, be to reach high contact by the way that in the molten steel body, adds powder material.Also have a series of additive methods in addition.

In known method, make the molten steel alloying overbasic slag that forms afterwards with manganese, although also have certain sulfide capacity, be helpless to the deep desulfuration of molten steel, stir because can not guarantee the fierceness of molten steel and slag in these cases.

Therefore, obtaining the low high-quality steel of sulphur content, to reduce its cost again simultaneously be impossible.

The oxygen blast meeting causes the unreasonable consumption of reductive agent, scaling loss, molten steel local excessive oxidation in manganese reductive reaction zone, reduce the sulfide capacity (or reducing the ability that absorbs sulphur) that forms surperficial slag, molten steel oxide and sulfide impurities are polluted, in other words, the degradation of steel, and cost increases.

After the carbon element work in-process have gone out, add various materials toward ladle together again and can reduce recovery in ladle manganese alloy element.This point will make the degradation and the cost up of steel with the speed that can not control alloying process.

Produce steel in this way than steel being carried out the productivity that alloying can reduce steel melting furnace with iron alloy.This is because add the process that all material can prolong alloying again after the carbon element work in-process are put into ladle, because material melts needs elapsed time, will reduce productivity like this and makes the cost up of steel.

The oxidation material that contains manganese alloy element that uses in aforesaid method is very expensive, because it is the big material of a kind of energy consumption.Because it can only be produced in electric arc, that is to say that its production will expend a large amount of electric energy, in addition, also needs very big facility investment.

Adopt this material can improve the price of steel.Under the situation of the manganese alloy element rate of recovery not high (80%) and reductive agent loss very high (reaching 20%), the price of steel also can increase.

In addition, manganese steel can only be obtained, and the steel alloy of other element can not be obtained with aforesaid method.

Owing in aforesaid method, exist the feature of mentioning, make its application in the production of steel be subjected to the production that the part can not be generalized to the low high-quality steel of sulphur content.

Task of the present invention is exactly to create a kind of like this method that adds the production normal steels of the oxidation material, reductive agent and the sweetening material that contain alloying element in the ladle, it can reduce the treating under the condition of course of processing cost, owing to the content of sulphur content that has reduced steel and nonmetallic impurity makes moderate progress the quality that obtains steel.

The solution of this task is as follows: in the production method of normal steels, be included in melting carbon element work in-process in the steel melting furnace, put it into ladle, in ladle, add sweetening material, reductive agent and contain alloying element through outside the heat treated oxidation material in advance, according to the present invention, reductive agent is added ladle in batches, a collection of is to add with sweetening material when the carbon element work in-process go out in the process that is less than 1/3 quality in the ladle, another batch is before the carbon element work in-process have gone out in the molten steel, with containing adding through heat treated oxidation material in advance of alloying element.

Use can reduce the gas saturation of steel through heat treated oxidation material in advance, because in heat treated process, has in fact just got rid of the combined moisture in the oxidation material.

Reduce the gas saturation of steel in the production process in ladle, just do not needed later vacuum-treat and other to be intended to reduce other treatment processs of gas in the steel.

Reduce gas in the steel, help to improve the quality of steel as the content of hydrogen and nitrogen, because reduced the flake susceptibility of steel and the dustiness of nitrogen phosphorus nonmetallic impurity.

In the heat-treatment process of oxidation material, destroyed without existing carbonate cpds in the heat treated material.Therefore, when handling the steel alloy of any element, use through heat treated oxidation material and can prevent that all the slag that forms from foaming and spill slag from ladle, can reduce the content of oxidation nonmetallic impurity in the Finished Steel simultaneously greatly.Can make the quality improvement of steel like this, also can save the additional refining that is intended to eliminate nonmetallic impurity in the steel.

In addition, can destroy the meltable high oxide that contains alloying element and sinter oxide compound at a low price in the heat treatment process of oxidation material, promptly part is got rid of the oxygen that is combined in the mineral.This method is very effective under heat treated reductive condition.

Reduce the oxygen level in the oxide compound contain alloying element, help to reduce the consumption of reductive agent in the alloy process and the quality of steel is improved and reduces cost owing to having reduced the oxidation nonmetallic impurity.

Add the fusing that helps the promote the oxidation material through heat treated material in advance in the ladle, form the slag of homogeneous, in this case, can improve the possibility of regulating and controlling the steel production process, thus the quality of raising steel.

When the carbon element work in-process are come out of the stove, in ladle, add the oxidisability level that reductive agent can be regulated steel in the tapping process in batches, just reduce the oxygen level of steel, this will have remarkable influence to the desulfurization degree of steel.

No matter the reinforced time is at the beginning of the carbon element work in-process are come out of the stove, the centre with hindering the half-finished even deoxidation of carbon element in a collection of adding ladle of reductive agent, also can reduce desulfurization degree after still having gone out.

First reductive agent is put into sweetening material, can make the deoxidation effectively in the process of coming out of the stove of carbon element work in-process, can quicken the fusing of sweetening material, that is to say, it can more early interact with molten metal more fully, the consumption that can also save reductive agent simultaneously.

So this thing happens in meeting, be because of reductive agent and oxygen, such as the oxygen that is dissolved in the carbon element work in-process body, interactional reaction.It has heat dissipating, i.e. the evolution of heat in reaction process.This heat is used to quicken the fusing of sweetening material, and in other words, they can participate in the desulphurization reaction of molten steel as soon as possible.Quicken homogenizing of sweetening material, help them can flow the molten steel interaction of strong agitation for a long time with the carbon element work in-process that are placed into ladle.All these helps to improve the desulfurization degree of steel, promptly improves the quality of steel.

Formed sulfide of the result of desulphurization reaction and oxysulfide all float molten steel surface, form covering slag.This layer slag can protect molten steel surface to avoid secondary oxidation, reduces the consumption of reductive agent.Reduce the content of nonmetallic impurity.

All these all can improve the quality of steel and reduce its cost.

Reductive agent and sweetening material add the production process technology index variation that will make steel respectively: the time is grown and causes desulfidation poor because sweetening material homogenizes, can not fully carry out thereby desulfidation is slowed down, can increase the consumption of reductive agent and the dustiness of the oxidation nonmetallic impurity that the consequent increases steel.These all can reduce the quality index of steel, and the cost of steel is increased.

Add first reductive agent with sweetening material in the ladle and can guarantee the effective desulfurization of molten steel in the carbon element work in-process are come out of the stove the process that is not more than quality 1/3, this is to overlap the result who carries out owing to add fusing, deoxidation of molten steel and three processes of molten steel desulfurizing of material.It is also very helpful to this that carbon element work in-process and reductive agent and sweetening material mix in ladle consumingly, and this is because the very big kinetic energy of the half-finished whereabouts of carbon element steel flow and cause the result of the convection current of molten steel by it.

In addition, when above-mentioned materials is added ladle together, also do not filled with 1/3 in ladle, just occur the slag of one deck homogeneous in the carbon element surface of semi-finished, it has the performance of very high absorption sulphur and can stop molten steel to carry out secondary oxidation by surface and oxygen in a large amount of.

All these helps to make molten steel desulfurization effectively, improves the quality of steel and reduces cost.

That night, a little (the carbon element work in-process have been appeared more than 1/3 of quality) was when adding ladle with first reductive agent with sweetening material, the energy of whereabouts carbon element work in-process stream can be absorbed by molten steel amount in the ladle, slacken metal and the convection process that adds material greatly, significantly reduce the deoxidation and the desulfurization rate of metal, thereby cause the too high consumption of material and make the downgrade of steel, cost up.

Another batch reductive agent can make the alloying process of steel and desulfurization have the economic oxidation material and the consumption of reductive agent with adding through the heat treated oxidation material that contains alloying element in advance.

So can be because when adding reductive agent and oxidation material, in ladle, possessed the good condition of carrying out metal alloyization and desulfurization like this.Oxygen level in metal oxygen level in the carbon element work in-process when coming out of the stove is much lower, and this is owing to add the cause of it having been carried out pre-deoxidation behind first reductive agent.Can reasonably consume reductive agent like this, make it under this condition, be used for fully alloying element is restored from oxidation material.

In addition, when adding second batch of reductive agent and oxidation material, the slag that forms in the metallic surface can be protected metal to avoid secondary oxidation and hinder second batch of reductive agent and the interaction of airborne oxygen.Because slag has the performance that absorbs sulphur, so it will continue the carbon element work in-process of new injection ladle are carried out effective desulfurization.So, the alloying process of steel has been overlapped with sweetening process.

All these all can improve the quality of steel owing to reducing sulphur content, and owing to rationally use reductive agent and make the refining process cost reduction of steel through the heat treated oxidation material that contains alloying element in advance.

If second batch of reductive agent and the oxidation material that contains alloying element are added respectively, will destroy this refining process of steel.

When at first adding oxidation material, will make its do sth. in advance to melt and mix with the covering slag that has formed, thereby slag is watered down, reduced the oxide compound that contains alloying element content partly, become alloying process very slow and can not fully alloying element be absorbed into diffusion process in the steel at reaction zone.In addition, can the sweetening process of metal be worsened owing to the oxide content that contains alloying element in covering slag composition is too high.This can make the quality of steel reduce, and must increase the additional consumption that contains alloying element oxidation material, sweetening material and reductive agent, and this will increase the cost of steel.

At first in ladle, add second batch of reductive agent, add the oxidation material that contains alloying element afterwards again, can cause the unreasonable consumption of reductive agent like this, may float the slag surface after its fusing, interact with airborne oxygen.Can increase the downgrade that makes steel because of the content of oxidation nonmetallic impurity like this, also make steel become expensive owing to reductive agent too much consumes.In addition, can make the production process of steel complicated, so that might produce the steel that to control chemical ingredients.

All material added before the carbon element work in-process have gone out in the ladle, and with iron alloy steel was carried out alloying process and compared the productivity that can not reduce steel melting furnace.

Alloying process is overlapped with sweetening process, not only can improve the quality of Finished Steel, also can reduce its price.This is because save an operation preface of carrying out refining desulfuration in special arrangement.

That recommends here overlaps alloying with desulfurization, only can both add under the condition of ladle just possible before the carbon element work in-process have gone out at all material.

As the fruit part material, such as, second batch of reductive agent is with adding in the ladle through the heat treated oxidation material that contains alloying element again after the carbon element work in-process have gone out in ladle in advance, at this moment alloying process just is difficult to control, and sweetening process is as getting special measure even can stop, and takes these measure meetings to improve the cost of steel, such as, additional preheating causes neutrality or reducing atmosphere etc. on the slag surface.

So can be like this, be because after the carbon element work in-process have gone out, in ladle, add material again in ladle, owing to lack whereabouts carbon element work in-process stream metal in the ladle mixed stirred effect, just changed the moving condition of molten steel treating processes in the ladle greatly.Do not have to mix and stir the moving process that can make in reduction and the desulfurization reaction zone and become very complicated, that is to say, react removing of after product, such as the element that restores from the oxide compound liquation, or reacted oxidation products comes out from its reaction zone.Alloying and sweetening process begin to be subjected to the restriction of original composition and reaction product diffusion.Speed this or the sort of reaction can significantly slow down.Also owing to be present in the slag composition of initial protion in the slag-contain the oxide compound of alloying element and have very high sulfide capacity, and make the temperature of original composition and concentration gradient point become bigger.Their major part concentrates at the upper strata of slag, and not at reaction zone.Being full of the element that the upper strata of the molten metal of smelting reduction agent is reduced out waters down consumingly.The partition ratio value of the alloying element between slag and the metal is in rapid variation, and the activity of slag interalloy element descends, and this will cause reduction rate to descend and reduce the possibility of control alloying process.This means the steel that might obtain the regulation chemical ingredients.These conditions can make the degradation of steel and increase its cost.

Preferably make reductive agent with alumina-bearing material.

According to its physical-chemical performance, under the condition of rationally utilizing, aluminium is one of best materials.It is widely adopted in the metallothermic reduction process.Aluminum ratio silicon or carbon are much higher to the affinity of oxygen, this just can reclaim alloying element to come out from slag more completely, the oxidation products of aluminium is alumina (aluminum oxide), and it can still less reduce the activity of slag interalloy element than the oxidation products-silica (silicon oxide) of silicon.Silica is the tangible acidic oxide of performance, in order it to be neutralized the general basic oxide that add calcium, magnesium and other elements that replenish again in reduction process in slag.The additional energy consumption that not only needs these additives melts it and will be raised to necessary temperature, can water down slag simultaneously, reduces the activity of slag interalloy element to a certain extent.All these can make the sweetening process of steel worsen, and reduce the rate of recovery from slag interalloy element, and steel is polluted by nonmetallic impurity, reduce the quality of steel and raise the cost.

Use aluminium to make reductive agent than the heat-treatability that can improve process with silicon, when replenished corresponding slag making of adding and sweetening material in the slag in case of necessity in the past, as lime, and must be for melting the additional again hectic fever carrier of these materials.

Must not increase under the situation that energy consumption melts supplementary material, replenish and add the sulfide capacity that sweetening material helps to improve slag, can directly in the ladle injection process, reduce the sulphur content of Finished Steel, and must on special device, not carry out additional desulfurization process steel at the carbon element work in-process.The cost that this helps to improve the quality of steel and reduces steel.

Wish to use aluminium base, calcium base and silicon-base alloy as reductive agent.

In containing the composition of al reducing agent, add silicon and calcium and can not only strengthen the deoxidation of carbon element molten steel, and can reinforcing desulfuration.Fully used the difference of these elements on its physics-chem characteristic in the method.When its was added ladle, it can make or even the very carbon element work in-process deoxidation of depths of static molten steel density than the big silicon of aluminium.This effect was just better when the steel flow that is fallen when the carbon element work in-process was stirred.When the actual temperature of molten metal in the ladle was 1550-1620 ℃, silicon can be as calcium, magnesium and is formed the gasiform oxide compound the aluminium in a way.Loss when therefore, it and airborne oxygen interact is unusually little.

This point helps the reasonable utilization of wrapping and it can improve the possibility of the treating processes of control steel in ladle.This just means the quality that can improve steel, reduces the cost of steel.

After entering the calcium adding ladle in the alloying constituent, other element-aluminium in alloy and silicon can not only improve the desulfurization degree of molten metal, can also help to form the covering slag that one deck has very high sulfide capacity.Form high temperature (1550-1620 ℃) that the gaseous calcium Chemistry and Physics Institute the needs high-vapor-pressure of calcium down, in the method for recommending, be used for guaranteeing the desulfurization of molten metal and do not have a gas phase loss of very big calcium.So can be so, be to make because in alloy, exist other composition-aluminium and silicon that the activity of calcium descends greatly in the alloy.In addition, the density of alloy is significantly higher than pure calcium, and therefore, the fusing of alloy is to carry out in the molten metal body, rather than at metallic surface, and what this will improve calcium effectively utilizes degree.

Aforesaid method owing to reduce sulphur content in the steel, and improves the quality of steel under using the situation of alloy, and is same owing to rationally utilize alloy, and the cost of steel is descended, and can reduce the alloy loss when interacting with airborne oxygen in addition.

The mixture of wishing to utilize aluminium base, calcium base and iron-based is as reductive agent.

Add iron in the composition of mixture and help to increase its density, it can be deep in molten metal or the slag body go.The density of mixture is higher than the density of the reductive agent in its composition, help to reduce reductive agent and the interactional loss of airborne oxygen, help to reduce the content of nonmetallic impurity in the steel, it is mutual to help to improve the desulfurization journey, thereby improve the quality of steel, reduce the cost of steel.

The mixture that will have high deoxidation and nature of devulcanization is in going out the half-finished process of carbon element in ladle, at first with sweetening material, add in the ladle through heat treated oxidation material with containing alloying element then, can make carbon element half-finished come out of the stove to overlap with its deoxidation, desulfurization and alloying carry out.

Use the mixture of recommending to guarantee to strengthen the process of producing steel in the ladle, must under the situation of replenishing processing on the isolated plant, not make steel improve its quality immediately after rolling.This also helps to reduce the cost of steel.

Be used under 900 ° to the 1250 ℃ temperature through the heat treated Mn oxide that contains in advance as being suitable through the heat treated oxidation material that contains alloy material in advance.

Use the heat treated oxidation material of process of any kind of can both eliminate it when melting contact with molten metal bubbing with the eliminating slag phenomenon of foaming.In slag, there is not the gaseous product of decomposing oxidation thing to help effective utilization, the loss when reducing it and entering oxygen in the decomposing gas composition and interact of reductive agent, owing to reduced oxide compound and sulfide oxidation nonmetallic impurity in the steel, and the quality of steel is improved, also can be because of not needing to take to improve the addition thereto of staff's labor condition and the unnecessary consumption of reductive agent, and the cost of steel is reduced.

If consider manganese is all arranged in the composition of most trade mark normal steels (its content account for mass percent 0.2 to 2.0), therefore, it is conspicuous adopting the extensive possibility of recommend method.

The selection that contains the pretreatment temperature of manganese oxidation material is subjected to following situation restriction, promptly in metallurgy refining operation in the composition of actual all manganese ores that use of institute, and the carbonate cpds of manganese and other elements in addition except combined moisture is arranged.

Therefore, in pyrometallurgical process, adopt so-called " life " ore will have bubbing, often cause liquation and molten steel from steel melting furnace or ladle, to spray.

Use is not less than 900 ℃ in temperature and descends the heat treated consumption that the manganese oxidation material can increase reductive agent that contains, and its loss can increase in the bubbing process.Can reduce the degree that manganese restores in this case from slag.In addition, this can cause steel to be polluted downgrade and cost up to cause steel by nonmetallic impurity.

Under temperature more than 900 ℃ and 900 °, heat-treat containing the manganese oxidation material, can pulverize the mineral of carbonates all in the manganese ore composition, also help manganese to the transition of oxide compound and contain less oxygen, this will reduce the consumption of reductive agent, raising from the effect that slag reclaims, improves manganese the quality of steel and reduces its cost.

Under temperature more than 1250 ℃, contain the thermal treatment of manganese oxidation material, can form the silicate that is difficult to reductive manganese, as Mn ₂SiO ₄(tephroite) or MnSiO ₃(rhodonite).

In addition, improve heat treated temperature and can increase the temperature of fusion that obtains material, this also can hinder fully carrying out of reduction process, impels molten steel to be polluted by nonmetallic impurity, promptly reduces the quality of steel and raises the cost.

Preferably the heat treated in advance manganese oxidation material that contains is sent in the ladle, molten metal is reasonably heated with neutral air-flow.

This reinforced method can guarantee can reclaim manganese more completely from contain the manganese metal in the carbon element work in-process are come out of the stove process in the ladle.

To add the heat treated oxidation material of process and overlap, so just solid slag making materials and sweetening material can be added ladle with while heating of metal liquation in ladle.Can the quality of steel be improved because of the sulphur content that reduces in the steel like this, also can contain the cost that the manganese oxidation material reduces steel owing to reasonably using through heat treated.

When will not being in the molten metal body that adds in the ladle through the heat treated manganese oxidation material that contains with neutral air-flow, but such as the surface that is added in molten steel, will reduce the reduction rate of manganese like this, the sweetening process of molten metal is deteriorated significantly, can can increase the content of the nonmetallic impurity in the steel owing to the loss that interacts and increase reductive agent with airborne oxygen.All these will reduce the quality of steel and increase cost.

Adding through molten metal not being heated in the heat treated oxidation material process in the molten metal body with neutral air-flow, will the temperature decline of molten metal owing to adding cold oxidation material and neutral gas.So just the carbon element work in-process must be placed in the steel melting furnace supplementary heating and make its undue oxidation, this means the consumption that will increase reductive agent, increase the quantity of nonmetallic impurity in steel, make the quality deteriorated of steel.

In addition,, fall into containing manganese oxidation material small-particle through Overheating Treatment and may not can melting fully of molten metal body, float to the separation surface of molten metal and slag and assimilated, thereby can make the reduction rate decline of manganese by the latter because the temperature of molten steel is low.This can increase the manganese oxide content that covers in the slag and reduce its sulfide capacity.The sweetening process of slag will worsen, and can reduce the quality of steel, improve its cost.

Wish to use the slag making mixture as sweetening material, it adds the amount of ladle, and be (1.0～1.1) in mixture and first ratio that adds reductive agent: (0.20～0.30) is selected.

In ladle, going out the carbon element work in-process, add reductive agent and slag making desulfurization mixture during beginning, can reduce the concentration that is dissolved in oxygen in the carbon element work in-process, this can cause the desulfurization condition of molten metal, and reaches the effect that enlarges markedly metal and slag surface in contact.

Liquid stream own guarantees that liquid stream at this moment has the ability that can bring the lip-deep slag making sweetening material of molten metal into the molten metal body together when being added to ladle 1/3 weight coming out of the stove to enlarge the strong convection current of slag and the intermetallic surface in contact molten metal that the kinetic energy of stream causes that will lean on the carbon element work in-process to fall and carbon element work in-process.

In addition, reductive agent and slag making sweetening agent are added simultaneously, owing to the scaling loss that molten slag layer has been avoided reductive agent is stamped in the metallic surface.Can reduce the consumption of reductive agent like this, reduce consuming, reduce the amount of nonmetallic impurity in the steel, thereby can improve the quality of steel, reduce its cost.

In this case, the amount of slag making sweetening agent and reductive agent is to be (1.0-1.1) according to the ratio of sweetening agent and first reductive agent: (0.20-0.30) definite, this amount can make the metal that has deoxidation in the carbon element work in-process are come out of the stove process in ladle and liquid molten slag layer on the metallic surface, and this will cause the favourable condition into the steel desulfurization.

When reductive agent consumption is reduced to when being lower than prescribed value, the deoxidation degree level of molten metal will descend, and promptly the content of oxygen drops to insufficient quantity in the liquation.This will reduce desulfurization degree.

When reductive agent consumption increases to when being higher than prescribed value, the nonmetallic impurity amount in the steel will increase, the cost up that this can reduce the quality of steel and make steel owing to the unreasonable consumption of material.

When the ratio that changes slag making sweetening agent and reductive agent, when the consumption that makes slag former changes toward the aspect that reduces, the desulfurization performance of slag and sulfide capacity thereof will descend, and increase to when being higher than prescribed value when the consumption of slag former, its homogenization process will prolong, can reduce desulfurization degree like this, so that reduce the quality of Finished Steel and increase cost.

Hope also replenishes when adding another batch reductive agent and adds sweetening material.

This charging process can make the half-finished deoxidation of carbon element, coincides with its alloying under the situation that keeps sweetening process, can obtain cheap high-quality steel like this under the situation of economical with materials consumption.When adding various material together in ladle, can also before the fusion deoxidation of carbon element work in-process intensive just not take place at oxidation material that contains alloying element and sweetening material.In this way create favorable conditions for the sweetening agent that from slag, restores alloying element and molten steel.

Have desulfurization on the molten metal surface and contain the oxidation material of alloying element, can protect molten metal to avoid secondary oxidation and guarantee rationally to use reductive agent, be actually prevent it with the interaction of airborne oxygen the required favourable condition of scaling loss.

Consider that the temperature of fusion of reductive agent always is lower than and contains alloying element oxidation material temperature of fusion, reductive agent will be to be melted in the body of molten metal than oxidation material faster speed.Therefore, when containing the oxidation material fusing of alloying element, the concentration of reductive agent in metallic substance is very high, therefore the process that restores element from liquation can carry out that this is extremely important for the process of producing steel in ladle with very high speed, will be accompanied by a large amount of thermal lossess and additional thermophore consumption because prolong the treatment time in this process.

The formed waste heat of reductive agent reaction result also helps to improve the speed of reduction process, and waste heat mainly is to consume melting sweetening material and containing on the oxidation material of alloying element, because when using metallic reducing agent, the reaction of reductive agent has exothermal nature.In this case, sweetening material rapid deterioration and raising cover the sulfide capacity of slag.

Rationally utilize reductive agent to help to reduce the content of nonmetallic impurity in the steel.All these is favourable with the cost that reduces steel to the quality that improves steel.

Add various materials respectively in the ladle and will destroy this process.At first only add second batch of reductive agent, will interact owing to oxygen and produce very high reductive agent loss, steel are polluted and worsen steel by nonmetallic impurity desulfurization condition with air.So can be like this, be because at reductive agent high flow rate (former consideration main available it come) with slag, do not have under the situation of alloying element oxide from slag reduction alloying element, very most reductive agent floats to the surface of slag and interacts with airborne oxygen after fusion, make molten metal be polluted the quality that these can reduce steel by nonmetallic impurity.In addition, when adding the oxidation material of alloying element, very most reductive agent uses up, therefore, from slag the process poor effect of reduction alloy material these heat condition of fusing sweetening material is worsened, thereby make the sweetening process variation of molten metal.

Earlier adding contains the oxidation material of alloying element in the ladle, and then adds other materials, can worsen the reduction and the sweetening process of molten metal like this.So can be like this, be because molten oxidation material mixes with the covering slag, can reduce the concentration of alloying element oxide like this, thereby worsen the reductive condition of alloy.In addition, the condition of molten metal desulfurization is variation also, and this is can cause the concentration of oxygen in redistributing of oxygen between slag and the metal and the molten metal to improve because improve the content of slag interalloy element oxide, and this will make the degradation of steel.

Hope acts as a supplement with rhombspar and adds sweetening material in the ladle, and its quantity is that 0.8-1.2 selects in rhombspar with the ratio that adds second batch of reductive agent.

Rhombspar is added ladle with second batch of reductive agent, in fact can avoid the scaling loss that interaction caused (loss) of oxygen in reductive agent and the air fully and help alloying element reduction more fully from slag.In this case, the rhombspar that adds ladle forms a protective layer on the slag surface, interacts with resistance～reductive agent floating upward slag surface and with airborne oxygen.

In this case, form the at utmost deoxidation layer of a slag, significantly increase its sulfide capacity at the separation surface of metal and slag.The molten metal desulfurization causes favourable condition in the molten steel, and this will help to improve the quality of steel and reduce its cost.

In addition, what form in the slag is being protected by the upper strata slag reliably along interface deep deoxidation layer, avoids secondary oxidation, and this is because the rhombspar that adds ladle helps to form infusibility layer above the slag with second batch of reductive agent.This also can help to improve the quality of steel.Reduce its cost.

Do not add the loss that rhombspar will increase reductive agent if add second batch of reductive agent because reductive agent after the deoxidation be easy to floating on slag surface and by airborne oxygen institute's oxidation and loss.Molten metal can take place in this case by airborne oxygen secondary oxidation.All these will cause the desulfurization degree of steel to reduce, the quality and the increase cost that increase the content of nonmetallic impurity in the steel and reduce steel.

Do not add can the deteriorate significantly desulfurization condition of molten metal of second batch of reductive agent if add rhombspar, this is owing to the deoxidation degree level of molten metal when adding rhombspar is the same as before, and the sulfide capacity of slag is then owing to its viscosity raising has reduced.This will make the downgrade of steel owing to the unreasonable use of rhombspar, and cost improves.

Amount in rhombspar can make the metal deoxidation for the ratio that adds second crowd of reductive agent 0.8-1.2 adds and the concentration on slag upper strata is increased.

When if the rhombspar that consumes is lower than the regulation ratio, then the upper strata slag can not thicken, this can cause the unreasonable use of reductive agent, owing to interact and loss with airborne oxygen, can reduce molten metal deoxidation degree level, worsen the desulfurization situation, and the quality of inevitable reduction steel and increase cost.

When the rhombspar that consumes is higher than the regulation ratio, slag is thickened fully, thereby lost its effect as the sweetening agent of steel, this also can make the degradation of steel, cost up.

When the reductive agent that consumes is lower than the regulation ratio, can reduces the deoxidation degree level of steel and correspondingly reduce desulfurization degree.If increased the consumption of reductive agent, it can be dissolved in and make it be higher than the concentration that requires of each concrete grade of steel in the molten metal, the steel grade chemical constitution that this can be against regulation.All these can reduce the quality of steel and increase cost.

Preferably use carbide of calcium as sweetening material, will add in batches.In this case, first carbide of calcium adds with first alumina-bearing material and lime, and its amount is (4.0-5.0) in aluminium in lime and the alumina-bearing material and carbide of calcium: (0.3-0.6): ratio (1.5-2.0).Replenish the carbide of calcium that adds and add with second batch of alumina-bearing material, its amount should be (1.0-1.2) mutually in the aluminium in the alumina-bearing material with carbide of calcium: ratio (2.5-3.6) is selected.

Begin to add the contact area maximum that slag making materials can guarantee metal and slag at the carbon element work in-process toward what ladle was injected, at this moment adding alumina-bearing material can guarantee best molten metal deoxidation this can make the worsening condition of desulfurization, and carbide of calcium itself is exactly good sweetening agent in the molten metal of deoxidation.

Lime is added ladle with alumina-bearing material and carbide of calcium can improve the sulfide capacity that forms slag on the molten metal surface.All these will help to improve the quality of steel and reduce cost, because reduced the content of sulphur in the composition of steel.

The consumption of lime is lower than the ratio of mentioning, and meeting is deficiency because carbide of calcium is fluxed, and causes the slag temperature of fusion to improve, and consequent reduction desulfurization degree, makes the metal quality variation.In addition because the surface of molten metal by its no slag protection secondary oxidation consumingly takes place in slag amount at least.The mistake high oxidation that can cause aluminium like this, too high consumption and in the molten metal body, form a large amount of nonmetallic impuritys, the quality that worsens the desulfurization situation and reduce steel increases the cost of steel.

It is improper too that the consumption of lime surpasses the ratio mention, because, can reduce the concentration of carbide of calcium in the slag in this case, the sulfide capacity of slag is reduced, the degradation that this can reduce desulfurization degree and make steel.In this case, reduce and make the cost up of steel from the rate of recovery of slag interalloy element.

The consumption of alumina-bearing material is lower than the ratio of proposition, can make molten metal deoxidation degree deficiency, can increase sulphur solubleness therein.And the reduction desulfurization degree, make the excessive variation and the cost up of steel.

The ratio that the consumption of alumina-bearing material is higher than proposition is not suitable for too, because the melting aluminum rising phenomenon can take place and by the oxidation of airborne oxygen institute when its is added molten metal.All these can cause, and nonmetallic impurity content increases in the steel, makes the downgrade of steel and owing to the unreasonable consumption of alumina-bearing material makes cost up.

The ratio regular meeting that the consumption of carbide of calcium is lower than proposition reduces to cause the degradation of steel the sulfide capacity of slag.

The consumption of carbide of calcium can cause the increase of slag temperature of fusion when being higher than the ratio of proposition, thereby increases viscosity, and this can make the desulfurization performance of slag reduce, and the quality of steel is reduced, and cost improves.

Second batch of carbide of calcium is added ladle through heat treated oxidation material and alumina-bearing material in advance with containing alloying element in the process that the carbon element work in-process are come out of the stove, can guarantee that molten metal alloying process and sweetening process coincide.This point can be distributed by the function of the material that adds ladle and reached.Increase the sulfide capacity that carbide of calcium can improve slag, increase the desulfurization degree of molten metal with this.To contain alloying element and add the alloy process and the additional deoxidation thereof that can guarantee molten metal through heat treated oxygen material in advance with alumina-bearing material, this can improve desulfurization degree too.The quality of steel is improved for all these and cost reduces.

When the consumption with carbide of calcium reduced to the ratio that is lower than proposition, the sulfide capacity that slag can occur descended, the degradation phenomenon of desulfurization degree reduction and steel.

When the consumption of carbide of calcium is surpassed the ratio that proposes, can cause slag to thicken, desulfurization level descends and the degradation and the cost up of steel.

When the consumption with alumina-bearing material reduces to the ratio that is lower than proposition, not foot phenomenon of molten metal deoxidation can appear, and this can cause the degradation of desulfurization reduction and steel.In addition, reduce the reduction ratio from slag interalloy element, this also can make the downgrade of steel, cost up.

When the consumption of alumina-bearing material is increased to the ratio that is higher than proposition, can become expensive, in addition, can make the degradation of steel because of the specific requirement scope that its aluminium content does not meet every kind of grade of steel because of its unreasonable consumption make the steel valency.

Therefore, the technology of recommendation can guarantee to improve the quality of steel and reduce its cost.

The production method of normal steels is implemented in the following manner.

Can adopt existing any stove, the converter of blowing as open hearth, electric furnace and oxygen, the agent of coal gas oxygen mix, neutral gas and other gas top blast, bottom blowing and mixing is as steelmaking equipment.The carbon element work in-process of melting following chemical components in steel melting furnace (by quality %):

Carbon-0.05-0.30

Manganese-0.05-0.10

Trace

Sulphur-below 0.30

Phosphorus-below 0.025

Iron-all the other.

Selecting the steel melting furnace of production carbon element finished product by the method for recommending is to be subjected to concrete grade of steel requirement commonly used is restricted, and can be determined by the production plant of steel.

The carbon element work in-process that obtained in steel melting furnace are put into ladle, the latter's capacity should with the capacity of steel melting furnace mutually suitably or be multiple.

In the process that the carbon element work in-process are come out of the stove, add sweetening material (mixture of lime, lime base, rhombspar, carbide of calcium and/or other) in the ladle.

When ladle by the carbon element work in-process be full of be no more than its quality 1/3 the time, add a collection of (part) reductive agent with sweetening material.Another part reductive agent is to add through heat treated oxidation material in advance with containing alloying element.Adding all these materials all will realize before the carbon element work in-process have gone out in the ladle.

Can adopt manganese containing materials, also can adopt contain chromium, contain vanadium, titaniferous and other materials be as containing alloying element through heat treated oxidation material in advance, with they respectively or as requested the chemical constitution of melting steel grade add in the ladle ordinatedly.

Containing alloying element must finish before the carbon element work in-process have gone out in ladle through the adding of heat treated oxidation material in advance.

Can use aluminium, calcium, silicon, iron, titanium and other basic alloy and mixture as reductive agent.Obtain the steel of required chemical ingredients at last.

Use in advance through heat treated oxidation material can avoid fully foaming of slag in the ladle also can prevent when the injection carbon element work in-process toward ladle in by ladle in splash molten steel and slag outward.Reduction process is steadily carried out and is in fact being contained alloying element in advance through not having chemical combination moisture content fully in the heat treated oxidation material, can significantly reduce the hydrogen in the gained steel and the gas amount of nitrogen, reduce the amount (they form) of the nonmetallic impurity in the steel when slag foams, improve the quality of Finished Steel and reduce its price with this.

The process of reduction alloying element is long in the heat treated oxidation material of process in advance from add ladle, in fact finishes with go out half-finished the finishing of carbon element in ladle.At this moment, the degree that reclaims alloying element from oxidation material in steel reaches 90～97%, has improved the degree of utilizing iron alloy directly to reclaim alloying element greatly.All these helps to obtain cheap steel.

Add reductive agent in the ladle in batches and can guarantee in the carbon element work in-process are come out of the stove process, to make its even deoxidation, reduce the loss of the reductive agent that causes owing to interacting with airborne oxygen, reduce the content of nonmetallic impurity in the steel, help the desulfurization of molten metal, these all can improve the quality of steel and reduce its price.

When disposable in ladle (a collection of) adds reductive agent, no matter the time that adds how-be in beginning, centre that the carbon element work in-process are come out of the stove or after having gone out, the half-finished deoxidation process of carbon element all can not evenly carry out.The desulfurization condition of molten metal is worsened, owing to the loss that interacts and increase reductive agent with airborne oxygen.Steel is polluted by the oxidation products of nonmetallic impurity, reductive agent.The degradation that all these all can make steel makes price become expensive.

A collection of reductive agent with sweetening material add can guarantee the molten metal desulfurization favourable condition this be because the desulfurization of deoxidation process and molten metal processing is carried out simultaneously.Reasonably utilized reductive agent in this case: virtually completely be used for the half-finished deoxidation of carbon element.It is also helpful to this to a great extent to have sweetening material in ladle.These sweetening materials form a molten slag layer on the molten metal surface after fusing, the protection molten metal is avoided secondary oxidation, and makes reductive agent avoid interacting to airborne oxygen.All these helps to obtain high-quality steel and reduces its price.

When respectively with a reductive agent and sweetening material adding ladle, this process is just destroyed.Adding reductive agent in advance can be owing to interacts with airborne oxygen, because the density of the reductive agent of fusing is littler than carbon element work in-process, so it floats over the surface of molten metal, thus it is directly contacted with airborne chlorine and by with mechanical melts in approach such as oxygen (because secondary oxidation constantly enter in the melts) interaction cause the very lossy of reductive agent.

This can make the further sweetening process deterioration of molten metal add the combustion of desulfurization material toward ladle in after, with the degradation that causes steel and improve its price.

Add sweetening material in the ladle and do not add reductive agent, can not guarantee to get rid of effectively sulphur from molten metal, because the very high this point (desulfurization) that influences of its deoxidation degree level, this can make the downgrade of steel, makes price become expensive.

A reductive agent is gone out in the process of 1/3 quality to add strong deoxidation and the desulfurization that ladle can guarantee molten metal at the carbon element work in-process with sweetening material.This is that its molten steel falls mobile can cause powerful molten metal in ladle convection current because the carbon element work in-process are when beginning to tap, and this helps it to mix with reductive agent and sweetening material.Can cause molten metal long-pending like this, can guarantee that like this with very high speed sulphur being rejected to the slag neutralization makes the molten metal deoxidation with the very large contact surface of sweetening material that in stirring, melts and reductive agent.In addition, the initial period in that the carbon element work in-process inject in the ladle, also do not form molten slag layer on the molten metal surface at that time, alkali plain half-finished fall to fail to be convened for lack of a quorum materials such as adding the reductive agent of ladle and sweetening agent is brought into the depths of molten metal.This also helps to increase the contact area of these materials and molten metal, and these can the content of sulphur makes the quality raising of steel and price is reduced in the steel owing to having reduced.

These materials add ladle very late, as be full of more than ladle 1/3 quality at the carbon element work in-process after, the mixing process that adds material (reductive agent and sweetening agent) is significantly worsened, and this is to absorb because fall the half-finished body of carbon element that the kinetic energy of stream injected ladle to a great extent.In this case, the desulfurization rate of molten metal and the sulphur uniformity coefficient along the ladle altitude distribution will significantly be reduced.The quality of steel is reduced and cost up.

Another part reductive agent can guarantee from slag strongly also fully to reduce alloying element with containing adding through heat treated oxidation material in advance of alloying element, consumes reductive agent economically and can not interrupt the desulfurization degree of molten metal.So can be like this, be because add second part of reductive agent and contain alloying element pass through heat treated chlorinatable material in advance the time, in ladle, had deoxidation well to have the molten metal of low sulfur content.Therefore, the reductive agent that adds ladle mainly consume with slag in the interaction of the alloying element oxide that exists, and have only very little amount to be used for newly injecting the half-finished deoxidation of carbon element of ladle.In ladle because on the molten metal surface that previous desulfurization forms and the covering molten slag layer that in reduction alloying element process from slag, increases volume again; protecting the surface of molten metal reliably; make its avoid secondary oxidation and with this reduce reductive agent because of with atmosphere in the loss that causes of the interaction of oxygen because desulfurization improves the quality of steel and reduces nonmetallic, oxide compound and foreign matter content oxidation of sulfureted.All these helps to reduce the price of steel.

With to contain adding respectively through heat treated oxidation material in advance of alloying element fashionable, this process is destroyed with reductive agent, so that reduces the quality of steel, increases the price of steel.

Add the unreasonable consumption that second part of reductive agent can cause it earlier, because adding second part still during agent, the oxygen level in the molten metal is very low, and has in the slag of very high sulfide capacity and do not have easy reductive oxide compound, as the oxide compound of iron, manganese, vanadium etc.Therefore, the reductive agent of fusing, its consumption are to determine that according to being used for the also original of alloying element the floating molten surface of going up interacts with airborne oxygen.This not only can cause the loss of reductive agent, and can make the degradation of steel because add later in the ladle contain alloying element can not guarantee the Restore All alloying element through heat treated oxidation material in advance, this will make the degradation of steel.

In addition, in liquation, there is new reductive alloying element oxide, can reduces its sulfide capacity, sweetening process is worsened, thereby reduce the quality of steel.

When at first add in the ladle contain alloying element through heat treated oxidation material in advance, and then it is also unreasonable to add reductive agent, because it makes slag saturated when these material melts, has therefore reduced its sulfide capacity and has worsened desulfurization condition.In addition, enter the partial oxygen in the alloying element oxide, be transformed in the fine molten metal that takes off peroxide this moment.Along with the carbon element work in-process of new injection also aerobic can enter in the molten metal.When not having reductive agent, in molten metal, can produce accumulating of oxygen, this will have very bad influence afterwards to the quality of steel, can increase the sulphur content of steel and the content of nonmetal oxide impurity.In this case, the price of steel can increase.

Before the carbon element work in-process have gone out, all material is all added ladle, can guarantee from slag, to restore alloying element strongly and the sweetening process of not interrupting it.This is because in the carbon element work in-process are being come out of the stove process, the caused convection current of kinetic energy that has intensive to be fallen to flowing by the carbon element work in-process in its body.In the process of coming out of the stove, the alloying element that the stirring of molten metal helps to be reduced is brought the depths of ladle into from reaction zone, and this helps the uniform distribution of these elements along the ladle height, also can aggravate reduction process simultaneously.Therefore, the reduction process of alloying element is to carry out under intensive is dynamic with very high speed, has in fact gone out just to finish up to the carbon element work in-process.

Can also guarantee from slag, very fully to reclaim alloying element like this.

After the carbon element work in-process have gone out, in ladle, add another part reductive agent again and contain alloying element through heat treated oxidation material in advance the time, can have a strong impact on the speed and the completeness of reduction alloying element from slag.The alloying element oxide that is not reduced will be dissolved in the slag, and its sulfide capacity is reduced, and this will reduce the quality of steel and increase its price.

Preferably use alumina-bearing material as reductive agent.

According to the affinity to oxygen, aluminium is to be widely used in most active element in the material of the deoxidation of metallurgical industry steel and reduction process.

Therefore, should at first ought push away alumina-bearing material in order rationally to utilize for reduction process.In addition, as using alumina-bearing material, the exothermicity of reduction process will improve, and can just improve the consumption of sweetening material like this to the molten metal supplementary heating.

When in ladle, producing steel, very important factor is exactly the rapidity of process, because production process prolongs the productivity that not only can reduce steel melting furnace, this can increase the cost of steel, and requiring supplementary heating to remedy the thermal losses of molten metal, the latter is directly related with the production time of steel in ladle.

If this steel melting furnace that can consume will be improved the temperature of carbon element work in-process before coming out of the stove.Like this, except meeting increases the cost of steel, also can reduce the quality of steel.This is because carbon element work in-process overheated oxygen level that often is accompanied by it in steel melting furnace increases, and just must add reductive agent in molten metal in order to reduce it, and the meeting of interaction of the latter and oxygen forms nonmetallic impurity.Nonmetallic impurity content increase the quality that will reduce steel.

Utilize the material of other element bases to make reductive agent, because they are to the high-affinity of oxygen and poor effect.For example, when using ferrosilicon, the exothermicity of reduction process has reduced, but in slag, increased acidic oxide proportion, it constitutes a whole set of compound with the oxide compound that contains alloying element, and the active of alloying element in the slag significantly descended, and reduces the degree that reclaims alloying element from slag, thereby reduce the quality of steel, increase the cost of steel.In addition, the content that increases acidic oxide in the slag can reduce its sulfide capacity, thereby makes the degradation of steel.

It is improper to utilize carbonaceous material to make reductive agent, because the reaction process of reduction alloying element has endothermic nature from slag, promptly absorb heat, for compensate it will add consume this consumption of energy carrier with compare with other metallic reducing agent will be high many, because what fusing contained alloying element must expend heat through thermal treatment oxidation material in advance.

All these all can reduce the quality of steel and make cost up.

When the manganese steel of any Chemical Composition of melting, it is through heat treated in advance under 900-1250 ℃ of temperature as this manganese oxidation material that contains of oxidation material that use contains the manganese oxidation material.

Select this oxidation material that contains alloying element manganese for use, be based on following reason, promptly in fact all contain manganese in all steel grades commonly used, its content is in 0.25 to 2.5%(quality) scope in.

Temperature is that 900-1250 ℃ thermal treatment temp is to be decided by the needs of getting rid of combined moisture in the oxidation material.As top said, the existence of combined moisture can cause slag to foam in the alloying process of steel and molten steel and slag spill from ladle, also can improve in the Finished Steel by gas, and as the pollution level of hydrogen, nitrogen, these can make the quality deteriorated of steel.

In addition, the thermal treatment that contains the manganese oxidation material under this temperature helps to destroy and contains the carbonate cpds that is had in the manganese oxidation material.As described above, it can cause slag to foam as combined moisture, metal and slag spill and make Finished Steel to be increased and increase the content of nonmetallic impurity by the pollution level of nitrogen, hydrogen from ladle, this will reduce the quality of steel and increase the cost of steel, because the refining that must take addition thereto to be intended to eliminate gas and to reduce nonmetallic impurity.

As adopt without thermal treatment or through 900 ℃ of following heat-treated contain the manganese oxidation material, as contain MnO ₂(pyrolusite), Mn ₃O ₄(hausmannite) and with the MnCO of carbonate form mineral ₃, CaCO ₃When the material, when these materials are added ladle, will resolve into the composition of oxide compound and carbonate and form gas cyaniding thing and carbonic acid gas.The gaseous product that oxidation material decomposes can make the slag in the ladle foam and impel metal and slag to spill from ladle.In addition, they can also make oxygen carry out the transition to from atmosphere in the slag body and go, and increase the consumption of reductive agent, increase the content of nonmetallic impurity in Finished Steel, make the downgrade of steel, make the cost up of steel simultaneously.

Contain the manganese oxidation material and heat-treat under 900 ℃ of following temperature and can not guarantee to get rid of fully combined moisture, the nonmetallic impurity that the latter's existence meeting is increased owing to steel and the pollution of nitrogen and hydrogen make its degradation.

Adding through heat-treated more than 1250 ℃ to contain the manganese oxidation material also improper because the oxidation material fusing will take place, can change its physics-chem characteristic under this temperature, especially can cause improving temperature of fusion.This point next step can cause reduction process in the ladle to prolong and the carbon element work in-process in ladle, gone out after also in the reduction process of this poor efficiency of continuation.

To in neutral gas stream, add ladle through heat treated manganese containing materials and can make the molten metal heating simultaneously.Like this, in fact, can reclaim manganese more completely from oxidation material has gone out in ladle up to the carbon element work in-process.

Make adding contain the heating of manganese oxidation material and molten metal and coincide, can replenish in ladle and add the desulfurization compound, can improve the quality of steel and the cost of reduction steel like this through heat treated in advance.

On the molten metal surface in ladle, add the heat treated manganese oxidation material that contains of process the reduction process of manganese is worsened, the desulfurization of severe exacerbation molten metal, this will reduce the quality of steel and increase its cost.

Adding through not allowing the molten metal heating can reduce the quality of steel heat treated containing in the manganese oxidation material process with neutral gas stream.So meeting so, is can make the liquation cooling because of add cold material in the molten metal body, reduction contains the burn-off rate of manganese oxidation material through Overheating Treatment, thereby the reductive condition of manganese is worsened, and means the desulfurization degree that reduces molten metal.Owing to the steel of steel is handled and had nervous thermal technology's standard and cannot replenish the adding sweetening material, thereby this situation is more serious.All these will make the degradation of steel and increase its cost.

Use slag making materials to should be (1.0-1.1) as sweetening material and in slag making materials mutually with the ratio that adds first part of reductive agent: (0.20-0.30) selected quantity adds ladle.

Sweetening agent adds with first part of reductive agent, can guarantee to make its deoxidation and desulfurization at the carbon element work in-process at the very start toward the ladle injection.In addition, the slag that forms on the molten metal surface has very high sulfide capacity.This just may improve the desulfurization degree of molten metal in the process that whole carbon element work in-process inject toward ladle.So can reduce the loss of reductive agent, be by it is not subjected to secondary oxidation and prevention reductive agent to float the slag surface and interacts with airborne oxygen at the slag protection that forms on the molten metal liquid surface.

The desulfurization slag former of selecting and the ratio of reductive agent are (1.0-1.1): (0.20-0.30), and the covering slag that can guarantee in ladle, to obtain the low deoxidation molten metal of tar content He have high sulfide capacity.When falling the consumption of sweetening agent to such an extent that be lower than the regulation of proposition, can reduce the desulfurization performance of slag, just reduce its sulfide capacity, can reduce the quality of steel and the cost of raising steel like this.

The consumption that increases sweetening agent can make the quality deteriorated of steel too, and this is because the slag that forms on the molten metal surface has very high viscosity.This can make the moving condition of molten metal desulfurization worsen.The consumption of reductive agent is lower than prescribed value can influence the deoxidation of steel and its desulfurization, and this also can make the degradation of steel.The reductive agent consumption is higher than prescribed value can cause its unreasonable use, and this can improve the cost of steel and increase the degradation restock when adding another part reductive agent that makes steel owing to nonmetallic impurity content and adds sweetening material.

Can be with rhombspar as sweetening material, its quantity is that 0.8-1.2 selects for use in the ratio of it and another part reductive agent.

Add material like this in ladle, can guarantee the reasonable use of reductive agent, this is that it blocks molten metal and is not subjected to secondary oxidation because form a protection molten slag layer on the molten metal surface after the rhombspar fusing.In addition, the slag of formation has very high sulfide capacity, and this can make the molten metal desulfurization, thus can improve steel quality and reduce cost.Adding reductive agent and rhombspar respectively can make the deoxidation of molten metal and sweetening process worsen.So can this thing happens be because, if in ladle, add reductive agent earlier, will increase its loss owing to interacting like this with airborne oxygen, can increase the amount of nonmetallic impurity in the steel, reduce the quality of steel.Add rhombspar too early slag is thickened, reduce its sulfide capacity, this can cause owing to the high quality that reduces steel of sulphur content.In addition, can cause the unreasonable consumption of reductive agent in this case, increase its loss owing to the oxygen in it and the atmosphere interacts.Can increase the cost of steel like this.

In another example of the present invention, use carbide of calcium as sweetening material.In this case, first part of carbide of calcium adds with first part of alumina-bearing material and lime, its amount should be (4.0-5.0) in lime mutually with aluminium and carbide of calcium in the alumina-bearing material: (0.3-0.6): ratio (1.5-2.0) is selected for use, and another part carbide of calcium and another part alumina-bearing material replenish adding, and its amount should be (1.0-1.2) in the aluminium in the alumina-bearing material mutually with the ratio of carbide of calcium: (2.5-3.6) select for use.

First part of carbide of calcium adds with lime and alumina-bearing material can guarantee carbon element work in-process deoxidation and desulfurization and form the slag that one deck has high sulfide capacity on the molten metal surface effectively, and all material is all reasonably used.Accomplishing this point, is because the slag protection molten metal that lime and carbide of calcium fusing back form is avoided the secondary oxidation of oxygen in the atmosphere, like this, can accomplish that when the molten metal deoxidation wherein the content of oxidation nonmetallic impurity is very low.Strong and in process deoxidation fully, at the carbon element work in-process for desulfurization creates favorable conditions.In fact deoxidation is to carry out in the interactional molten metal of isolated and airborne oxygen.

Therefore, when carbide of calcium melts also in the desulfurization of carrying out molten metal.

The lime that adds ladle with carbide of calcium and alumina-bearing material helps to have the molten slag layer of high sulfide capacity in the formation of molten metal surface.All these help to obtain high quality and steel cheaply.

The consumption that increases carbide of calcium can make slag thicken, the result can reduce its sulfide capacity, owing to the loss that interacts and increase reductive agent with airborne oxygen, worsens desulfurization condition, increase the amount of nonmetallic impurity in the steel simultaneously, these can make the degradation of steel and increase its cost.

Reduce the consumption of carbide of calcium, can make the sweetening process of molten metal worsen and obtain having the slag of protosulphide capacity, this will reduce the quality of steel.

The too high consumption of alumina-bearing material can cause its unreasonable use and make the steel valency become expensive.Thereby reducing alumina-bearing material consumption can make the deoxidation of steel and desulfurization worsen the quality that reduces steel.

The consumption that improves lime can make slag thicken, and reduces its sulfide capacity, and molten metal deoxidation and desulfurization are worsened, and this is owing to airborne oxygen interaction the loss of alumina-bearing material being increased.In addition, the nonmetallic impurity amount in the steel increases.Quality of steel is reduced for these and cost improves.

The consumption that reduces lime can increase the scaling loss of alumina-bearing material owing to interacting with airborne oxygen equally.This can improve the content of nonmetallic impurity in the steel, and reduces desulfurization degree.These all can make the degradation of steel, and cost increases.

Add second part of carbide of calcium with replenishing through heat treated oxidation material in advance and another part alumina-bearing material, its amount should be (1.0-1.2) in the aluminium in the alumina-bearing material mutually with the ratio of carbide of calcium: 2.5-3.6) come selectedly, can guarantee the new half-finished deoxidation of carbon element of injecting, desulfurization and carry out simultaneously from the process of slag reduction alloying element.Reach alumina-bearing material-reductive agent that this point just must make adding, be by covering slag protection not by the oxidation of the institute of the oxygen in the atmosphere, effectively be dissolved in the oxygen in the carbon element work in-process and be included in that the oxygen in the alloying element oxide interacts in the slag.

Therefore, be that the desulfurization of molten metal creates favorable conditions by the carbide of calcium of fusing.Carbide of calcium can also improve the sulfide capacity of slag in addition, and it also will have the contact of tart oxide compound in the synthetic compound.Consequently obtain high quality and steel cheaply.

When adding various material respectively, this process will be destroyed, and can make the degradation and the cost up of steel.

At first add and contain alloying element, can produce the intensive fusing and slag is watered down through heat treated oxidation material in advance.In this case, the oxide concentration that contains what is called " vivaciously " oxygen in the composition of slag has improved, and that is to say that the unstable oxide compound of heating power is that the concentration that contains the oxide compound of alloying element has improved under this situation.At this moment between molten metal and slag, take place oxygen redistribute and molten metal in the concentration of oxygen also improved.This can make the desulfurization condition of molten metal worsen and cause the downgrade of Finished Steel.In addition, the condition of reduction alloying element also worsens from slag, and this will make the degradation of steel.

After adding second part of carbide of calcium and reductive agent, add again and contain also having little effect of alloying element, only can cause its a large amount of losses because former consideration mainly is the too high consumption of the reductive agent of reduction alloying element from slag through heat treated oxidation material in advance.Remaining reductive agent floats last slag surface and interacts with airborne oxygen.All these will reduce steel quality and increase its cost.

When the consumption of carbide of calcium surpasses the ratio that proposes, slag is thickened, reduce its sulfide capacity, these can reduce the desulfurization degree of steel.In addition, because the viscosity of slag is big, this causes difficulty with regard to the process for reduction alloying element from slag.All these, nature can make the degradation of steel and make cost up.

The consumption of carbide of calcium in reducing by second part (lower than the ratio that improves) can worsen owing to the sulfide capacity that has reduced slag makes the desulfurization condition of molten metal, and this will cause the downgrade and the cost up of steel.

The ratio regular meeting that the consumption of reductive agent is higher than proposition causes its unreasonable use, too high scaling loss, degradation and cost up that steel is polluted by nonmetallic impurity and will inevitably make steel.

The ratio regular meeting that the consumption of reductive agent is lower than proposition causes the residue too high levels of oxygen in the steel, and it will stay with the form of nonmetallic impurity when steel solidifies.

In addition, reduce the rate of recovery that from slag, reclaims alloying element, can cause the against regulation chemical ingredients of steel.In this case, the desulfurization condition of molten metal is worsened.All these can cause steel and downgrade, cost up.

Therefore, when using when heat treated material, reductive agent above-mentioned, sweetening material, slag making materials and consumption in accordance with regulations specifically add ladle in advance, the method for this production steel of recommendation can improve the quality of steel and makes the method for this production steel commonly used with low cost owing to the content that has reduced sulphur content and nonmetallic impurity.

To the present invention be illustrated by the example of specifically finishing below.

In addition, enumerate method (SU, A, a 1044641) example (example 26) in order to contrast by existing explained hereafter steel.

The chemical constitution of Finished Steel and characteristic thereof are all listed in table 1.

Example 1

The method of producing chrome-bearing steel is to carry out in volume is 350 tons casting ladle.The carbon element work in-process are to put into ladle with 1650 ℃ temperature from top-blown oxygen converter.The cylinder-packing of casting ladle is that the refractory materials with high alumina is built into.

As oxidation material, used 1600 ℃ of heat treated in advance its chemical constitutions of chromium material (quality %) that contain of temperature to be: 70.81-Cr ₂O ₃; 12.20-FeO; 9.31-Al ₂O ₃; 5.94-SiO ₂; 1.74-MgO.

Used the fluorite mixture as sweetening material, it contains (by quality %) and is not less than 75.0-CaF ₂; All the other are other incidental impurity and the lime that newly burns till, and it contains (quality %): CaO-92.0 and MgO-6.5, and all the other are other incidental impurities.

Used alumina-bearing material as reductive agent: aluminum base alloy, contain principal element-aluminium-Yue 86%, all the other-impurity.Reductive agent adds with sweetening material.

A alumina-bearing material and sweetening material have added ladle when reaching 1/3 quality (0.1 ton) when the carbon element work in-process charge into together.Then 5.7 tons the alumina-bearing material that contains 1.8 tons of chromium oxidation material and another parts before having gone out in the ladle, the carbon element work in-process is added ladle together.

Finished Steel is cast on the continuous billet casting machine, and the steel billet section is that 3 50 * 1650mm is rolled into it the steel plate that thickness is 10-30mm then and has carried out metallographic examination.

Obtain the steel of following chemical constitution (quality %): C-0.12; Si-0.25; Mn-0.55; S-0.004; P-0.020; Al-0.020; Cr-0.49; Ni-0.70; Cu-0.45; Fe-all the other.At this moment, the rate of recovery of chromium is 96.3%, desulfurization degree-71.4%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.6; Sulfide-1.8; Silicate-1.9.

What obtain is the high-quality steel because sulphur content and nonmetal content is low.

Example 2

The production method of steel commonly used realizes the melting in 100 tons of electric arc furnace of carbon element work in-process in the casting ladle.

As the oxidation material that contains alloying element, that has used under 900 ℃ of temperature heat treated in advance contains the manganese oxidation material, and its composition (quality %) is: MnO+Mn ₃O ₃+ Mn ₃O ₄-54.8(is Mn-42.3 wherein); SiO ₂-18.0; Fe ₂O ₃-2.3; Al ₂O ₃-3.0; CaO-5.0; MgO-2.1; C-2.2; P-0.15; S-0.015; Other incidental impurities-12.435.

For the material and the fluorite of lime base have been adopted in desulfurization, situation about mentioning in its composition and the example 1 is similar: adopted metallic reducing agent-aluminum base alloy as reductive agent, its composition also situation with example 1 is similar.

When obtain 1640 ℃ carbon element work in-process at electric arc furnace after, it is put into ladle with 6 minutes, its cylinder-packing is a fireclay.

A reductive agent weighs 60 kilograms and goes out in the process of 1/3 weight to add ladle when the carbon element work in-process with 0.5 ton sweetening materials.

Another part reductive agent weighs 0.565 ton of manganese oxidation material that contains with 3.5 tons and added ladle before the carbon element work in-process has gone out.

The casting of Finished Steel, rolling and metallographic examination is similar to last example.

Obtain the steel (quality %) of following chemical constitution: C-0.12; Si-0.22; Mn-1.51; S-.007; P-0.011; Al-0.022; Fe-all the other.

At this moment, the rate of recovery of manganese is 95.27%, desulfurization degree-64.5%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.3; Sulfide-2.2; Silicate-1.7.

Because sulphur content and nonmetallic impurity content are low, what obtain is the high-quality steel.

Example 3

The working system of steel commonly used is realized situation such as example 22 in 100 tons of casting ladle.

Used material and consumption thereof are all identical with example 1.

The oxidation material that different is contains alloying element has used under 1100 ℃ of temperature through heat treated the manganese oxidation material that contains, its chemical constitution such as example 2 in advance.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.11; Si; 0.23; Mn-1.53; S-0.008; P-0.010; Al-0.023; Fe-all the other.

At this moment, the rate of recovery of manganese is 95.94%, desulfurization degree-61.9%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.4; Sulfide-2.4; Silicate-1.8.

Because sulphur and nonmetallic impurity content are low, what therefore obtain is the high-quality steel.

Example 4

The production method of steel commonly used realizes in 100 tons of casting ladle, as example 2 and 3.

Same material and same consumption thereof have been used.Different is has used under 1250 ℃ of temperature through heat treated the manganese oxidation material that contains, its chemical constitution such as example 2 in advance as the oxidation material that contains alloying element.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.12; Si-0.3; Mn-1.52; S-0.007; P-0.022; Al-0.022, Fe-all the other.

At this moment, the rate of recovery of manganese is 94.49%, desulfurization degree-63.6%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.5; Sulfide-2.0; Silicate-1.9.

Because the content of sulphur and nonmetallic impurity is low, resulting is the high-quality steel.

Example 5

The production method of steel commonly used realizes in 100 tons of casting ladle, as routine 3-4.The material and the consumption thereof that use are all identical with example 3.It is to add ladle in the air-flow at neutral gas-argon that difference is in manganese containing materials, meanwhile, also the molten metal in the ladle has been carried out electric-arc heating.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

Resulting steel has following chemical constitution (quality %): C-0.12; Si-0.21; Mn-1.55; S-0.004; P-0.012; Al-0.024; Fe-all the other.

At this moment, the rate of recovery of manganese is 97.9%, desulfurization degree-83.2%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.2; Sulfide-1.4; Silicate-1.6.

Because the content of sulphur and nonmetallic impurity is low, so what obtain is the high-quality steel.

Example 6

The production method of steel commonly used is carried out in the casting ladle, and is similar to example 5.

Used material as sweetening material based on lime and fluorite.

Difference is to contain the oxidation material quality of alloying element, has adopted following material:

-under 1100 ℃ of temperature through the heat treated manganese oxidation material that contains in advance, similar to the material of example 2:

-heat treated vanadium the oxidation material that contains of process under 1600 ℃ of temperature, its composition is (quality %): V ₂O ₅-85(is V-47.77 wherein); Al ₂O ₃-0.4; TiO ₂-1.8; SiO ₂-2.5; CaO-1.1Fe ₂O ₃-7.0; MgO-0.6; S-0.3; P-0.07; Other incidental impurities-0.23.

Used metallic reducing agent-aluminum base alloy as reductive agent, the alloy phase that uses in its chemical constitution and the example 1 seemingly.

Carbon element work in-process with 1645 ℃ of temperature are to refine in electric arc furnace, in 6.5 minutes process it are injected in the casting ladle with fireclay liner then.

The a reductive agent that weighs 0.07 ton adds ladle with sweetening material when the carbon element work in-process fill into 1/3 quality.At this moment, the weight of sweetening material is 0.55 ton.

Another part reductive agent and oxidation material are to add ladle in the air-flow of neutral gas-argon, also molten metal have been carried out electric-arc heating simultaneously.

At this moment the quality of reductive agent is 0.63 ton, contains manganese oxidation material-3.5 ton, contains vanadium oxidation material-0.225 ton.

The casting of Finished Steel, rolling and metallographic examination is similar to example 1.

The steel that obtains has following chemical constitution (quality %): C-0.10; Si-0.22; Mn-1.51; S-0.004; P-0.011; V-0.10; Al-0.022; Fe-all the other.

At this moment, the rate of recovery of manganese is 93.7%, the rate of recovery of vanadium-94.2%, desulfurization degree-79.2%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.3; Sulfide-1.8; Silicate-1.8.

Because sulphur and nonmetallic impurity content are low, what obtain is the high-quality steel.

Example 7

The production method of steel commonly used realizes that situation is similar to example 1 in 350 tons of casting ladle.

Used the mixture similar as sweetening material to example 1.

Used under 1100 ℃ of temperature through heat treated the manganese oxidation material that contains, its chemical constitution such as example 2 in advance as the oxidation material that contains alloying element.

Used metallic reducing agent-aluminum base alloy, its chemical constitution such as example 1 in order to reduce alloying element.

Carbon element work in-process melting to 1650 ℃ is injected by converter and is had in the ladle of fireclay liner 6 minutes times spent.

When the carbon element work in-process charge into when reaching 1/3 quality, in ladle, add a reductive agent and sweetening material, its quantity is respectively 0.46 ton and 2.3 tons, adds another part reductive agent with containing the manganese oxidation material then before the carbon element work in-process have gone out, and its quantity is respectively 112.6 tons and 1.9 tons.

The casting of Finished Steel, rolling similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.09; Si-0.62; Mn-1.43; S-0.005; P-0.007; Al-0.027; Fe-all the other.

At this moment, the rate of recovery of manganese is 95.0%, desulfurization degree-61.2%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.4; Sulfide-1.8; Silicate-1.9.

Because sulphur and nonmetallic impurity content are low, what obtain is the high-quality steel.

Example 8

The production method of steel commonly used realizes that situation is similar to example 7 in 350 tons of casting ladle.

The material and the consumption thereof that use are identical with example 7.

The consumption that difference is reductive agent and sweetening material has used slag former as sweetening material, and it is added in the ladle with a reductive agent.

In this example, the consumption of slag former is 2.3 tons, and reductive agent is 0.69 ton, and promptly slag former should be 1.0: 0.3 mutually with the ratio of first part of reductive agent quantity.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.10; Si-0.60; Mn-1.46; S-0.004; P-0.010; AAl-0.033; Fe-all the other.

At this moment, the rate of recovery of manganese is 97.9%, desulfurization degree-58.4%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.5; Sulfide-1.9; Silicate-1.9.

Because the content of sulphur and nonmetallic impurity is low, what obtain is the high-quality steel.

Example 9

The production method of steel commonly used is to realize that situation is similar to example 7 in 350 tons casting ladle.

Used material and consumption thereof are identical with example 7.Difference is the consumption of reductive agent and sweetening material.The latter adds ladle with a reductive agent, has used slag former as reductive agent.In this example, the consumption of slag former is 2.5 tons, and reductive agent-0.45 ton, promptly the ratio of the two should be 1: 1: 0.2 mutually.

The casting of Finished Steel, rolling with check is similar to example 1 mutually entirely.

The steel that obtains has following chemical constitution (quality %): C-0.10; Si-0.63; Mn-1.42; S-0.005; P-0.010; Al-0.030; Fe-all the other.

At this moment, the rate of recovery of manganese is 95.6%, desulfurization degree-55.9%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.3; Sulfide-1.8; Silicate-1.8.

Because the nonmetallic impurity content of sulphur is low, what obtain is the high-quality steel.

Example 10

The production method of steel commonly used realizes that situation is similar to example 7 in 350 tons of casting ladle.

Employed material and consumption thereof are all identical with example 7.Difference is the consumption of reductive agent and sweetening material, and the latter adds ladle with a reductive agent.At this moment, the consumption of reductive agent is 0.47 ton, and sweetening material-1.72 ton, the ratio of the two should be 0.3: 1.1 mutually.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.11; Si-0.54; Mn-1.46; S-0.006; P-0.012; Al-0.024; Fe-all the other.

At this moment, the rate of recovery of manganese is 93.7%, desulfurization degree-63.1%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.6; Sulfide-1.4; Silicate-1.7.

Because the content of sulphur and nonmetallic impurity is low, gained be the high-quality steel.

Example 11

Production method commonly used realizes that situation is similar to example 7 in 350 tons of casting ladle.

The material and the consumption thereof that use are identical with example 7.Difference is that on the consumption of reductive agent and sweetening material, the latter adds ladle with a reductive agent.At this moment, the consumption of sweetening material is 1.95 tons, reductive agent-0.46 ton, and promptly the ratio of the two should be 1.05: 0.25 mutually.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.12; Si-0.57; Mn-1.49; S-0.004; P-0.011; Al-0.034; Fe-all the other.

The manganese recovery ratio of this moment is 96.7%, desulfurization degree-64.9%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.4; Sulfide-1.3; Silicate-1.6.

Because the content of sulphur and nonmetallic impurity is low, so what obtain is the high-quality steel.

Example 12

The production method of steel commonly used realizes that situation is similar to example 6 in 100 tons of casting ladle.

Used same material.Difference is to contain the consumption of manganese oxidation material, is 1.2 tons herein.

In addition, in this example, with another part reductive agent with contain the manganese oxidation material and replenish to have added sweetening material toward ladle in, its chemical constitution is similar to the material of use in the example 1, and its consumption is 0.5 ton, and the consumption of another part reductive agent is 0.2 ton.

The casting of Finished Steel, rolling similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.10; Si-0.24; Mn-0.51; S-0.004; P-0.012; Al-0.031; Fe-all the other.

At this moment, the rate of recovery of manganese is 93.8%, desulfurization degree-82.4%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.7; Sulfide-1.4; Silicate-1.6.

Because sulphur and nonmetallic impurity content are low, what obtain is the high-quality steel.

Example 13

The production method of steel commonly used realizes that at 100 tons of casting molten steel situation is similar to example 12.

Same material and same consumption have been used.Difference is, with the additional composition that adds the sweetening material of ladle of another part reductive agent.Sweetening material is by 70%-CaO in this example, 10%-CaF ₂And 20%Al ₂O ₃Form, its consumption is 0.5 ton.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.12; Si-0.21; Mn-0.49; S-0.006; P-0.010; Al-0.026; Fe-all the other.

At this moment, the rate of recovery of manganese is 94.4%, desulfurization degree-74.9%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.8; Sulfide-1.9; Silicate-2.1.

Because the content of sulphur and nonmetallic impurity is low, what obtain is the high-quality steel.

Example 14

The production method of steel commonly used is to realize that situation is similar to example 12 in 100 tons casting ladle.

Used identical materials and consumption thereof, difference is, replenishes the composition of the sweetening material that adds simultaneously with another part reductive agent.

Sweetening material in this example is by 60%-CaO, 10%-MgO, 5%-CaF ₂And 25%-Al ₂O ₃Form, its consumption is 0.5 ton.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.10; Si-0.28; Mn-0.50; S-0.006; P-0.012; Al-0.028; Fe-all the other.

At this moment, the rate of recovery of manganese is 95.6%, desulfurization degree-71.4%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.9; Sulfide-1.8; Silicate-2.0.

Because sulphur and nonmetallic impurity content are low, what obtain is the high-quality steel.

Example 15

The production method of steel commonly used realizes that situation is similar to example 11 in 350 tons of casting ladle.

Same material and consumption thereof have been used.Difference is, with another part reductive agent with contain the manganese oxidation material to replenish the sweetening additive that adds ladle be rhombspar, its consumption is 0.8 to select for use by the ratio of rhombspar and another part reductive agent.The consumption of rhombspar is 1.75 tons in addition.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.09; Si-0.57; Mn-1.48; S-0.005; P-0.012; Al-0.020; Fe-all the other.

At this moment, the rate of recovery of manganese is 93.7%, desulfurization degree-79.4%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.7; Sulfide-1.5; Silicate-1.9.

Because the content of sulphur and nonmetallic impurity is low, what obtain is the high-quality steel.

Example 16

The production method of steel commonly used realizes that situation is similar to example 15 in 350 tons of casting ladle.

Identical materials and consumption thereof have been used.Difference is, adds the consumption of the rhombspar of ladle with another part reductive agent.Herein, the consumption of rhombspar is 1.0 to select for use by the ratio of rhombspar and another part reductive agent.The consumption of rhombspar is 2.2 tons herein.

The casting of Finished Steel, rolling all similar to example 15 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.12; Si-0.51; Mn-1.51; S-0.006; P-0.015; Al-0.027; Fe-all the other.

Herein, the rate of recovery of manganese is 96.1%, desulfurization degree-74.6%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.7; Sulfide-1.9; Silicate-1.5.

Because the content of sulphur and nonmetallic impurity is low, what obtain is the high-quality steel.

Example 17

The production of steel commonly used realizes that situation is similar to example 15 in 350 tons of casting ladle.

Identical materials and consumption thereof have been used.Difference is, adds the consumption of the rhombspar of ladle with another part reductive agent.In this example, the consumption of rhombspar is that the ratio by rhombspar and another part reductive agent is 1.2 to select for use, and the rhombspar consumption of this moment is 2.6 tons.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.10; Si-0.56; Mn-1.46; S-0.005; P-0.012; Al-0.021; Fe-all the other.

The manganese recovery ratio of this moment is 93.9%, desulfurization degree-76.8%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.5; Sulfide-1.4; Silicate-1.8.

Because sulphur and nonmetallic impurity content are low, what therefore obtain is the high-quality steel.

Example 18

The production method of steel commonly used realizes that situation is similar to example 12 in 100 tons of casting ladle.

Same material and consumption thereof have been used.Difference is, in this example as add with a alumina-bearing material and replenish the sweetening material that adds with another part alumina-bearing material and be to use carbide of calcium.Carbide of calcium adds ladle with a alumina-bearing material and lime, and its quantity is that the ratio in aluminium in lime and the alumina-bearing material and carbide of calcium should be 4.0: 0.3: 1.5 mutually and selects for use.

The total flow of lime, alumina-bearing material and carbide of calcium is 0.6 ton.

With carbide of calcium quantity that another part alumina-bearing material adds ladle is that ratio in aluminium in the alumina-bearing material and carbide of calcium should be 1: 2.5 mutually and selects for use.This moment, the consumption of carbide of calcium was 0.3 ton.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.10; Si-0.21; Mn-0.52; S-0.004; P-0.014; Al-0.023; Fe-all the other.

At this moment manganese recovery ratio is 94.7%, desulfurization degree-79.1%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.5; Sulfide-1.2; Silicate-1.8.

Because the content of sulphur and nonmetallic impurity is low, what therefore obtain is the high-quality steel.

Example 19

The production method of steel commonly used realizes that situation is similar to example 18 in 100 tons of casting ladle.

Same material and consumption have been used.Difference is the consumption of carbide of calcium.Carbide of calcium adds ladle with a material and lime, and its quantity is that the ratio in aluminium in lime and the alumina-bearing material and carbide of calcium should be 4.0: 0.6: 1.5 mutually and selects for use.

The total flow of lime, alumina-bearing material and carbide of calcium is 0.6 ton.

With quantity that another part alumina-bearing material adds the carbide of calcium of ladle together is that ratio by the aluminium in the alumina-bearing material and carbide of calcium should be 1: 3.6 mutually and selects for use.This moment, the consumption of carbide of calcium was 0.55 ton.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.12; Si-0.24; Mn-0.49; S-0.006; P-0.019; Al-0.024; Fe-all the other.

The manganese recovery ratio of this moment is 92.3%, desulfurization degree-76.8%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.8; Sulfide-1.9; Silicate-2.0.

Because the content of sulphur and nonmetallic impurity is low, what therefore obtain is the high-quality steel.

Example 20

The production method of steel commonly used realizes that situation is similar to example 18 in 100 tons of casting ladle.

Same material and consumption thereof have been adopted.Difference is the consumption of carbide of calcium.With quantity that a alumina-bearing material and lime add the carbide of calcium of ladle together is that ratio in aluminium in lime and the alumina-bearing material and carbide of calcium should be 4.0: 0.5: 2.0 mutually and selects for use.

The total flow of lime, alumina-bearing material and carbide of calcium is 0.6 ton.

With amount that another part alumina-bearing material adds the carbide of calcium of ladle together is that ratio in aluminium in the alumina-bearing material and carbide of calcium should be 1: 30 mutually and selects for use.At this moment the consumption of carbide of calcium is 0.45 ton.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.09; Si-0.21; Mn-0.52; S-0.005; P-0.016; Al-0.021; Fe-all the other.

The manganese recovery ratio of this moment is 96.3%, desulfurization degree-79.8%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.6; Sulfide-1.7; Silicate-1.9.

Because the nonmetallic impurity content of sulphur is low, so what obtain is the high-quality steel.

Example 21

The production method of steel commonly used realizes that situation is similar to example 18 in 100 tons of casting ladle.

Same material and consumption thereof have been used.Difference is the consumption of carbide of calcium.

With quantity that a alumina-bearing material and lime add the carbide of calcium of ladle together is that ratio in aluminium in lime and the alumina-bearing material and carbide of calcium should be 4.0: 0.5: 1.7 mutually and selects for use.

The total flow of lime, alumina-bearing material and carbide of calcium is 0.6 ton.

With quantity that another part alumina-bearing material adds the carbide of calcium of ladle is that ratio in aluminium in the alumina-bearing material and carbide of calcium should be 1.2: 2.5 mutually and selects for use.The carbide of calcium consumption here is 0.35 ton.

The casting of Finished Steel, rolling all similar to example 18 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.10; Si-0.25; Mn-0.54; S-0.006; P-0.018; Al-0.023; Fe-all the other.

At this moment manganese recovery ratio is 97.1%, desulfurization degree-74.9%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.7; Sulfide-1.9; Silicate-1.6.

Because the content of the nonmetallic impurity of sulphur is low, what therefore obtain is the high-quality steel.

Example 22

The production method of steel commonly used realizes that situation is similar to example 18 in 100 tons of casting ladle.

Same material and consumption thereof have been used.Difference is the consumption of carbide of calcium.

With quantity that a alumina-bearing material adds the carbide of calcium of ladle and stone calamity together is that ratio in aluminium in lime and the alumina-bearing material and carbide of calcium should be 5.0: 0.3: 1.5 mutually and selects for use.

The total flow of lime, alumina-bearing material and carbide of calcium is 0.6 ton.

With quantity that another part alumina-bearing material adds the carbide of calcium of ladle is that ratio in aluminium in the alumina-bearing material and carbide of calcium should be 1.2: 3.6 mutually and selects for use.

At this moment carbide of calcium consumption is 1.08 tons.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.11; Si-0.23; Mn-0.51; S-0.004; P-0.021; Al-0.025; Fe-all the other.

At this moment manganese recovery ratio is 95.3%, and desulfurization degree is 79.8%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.6; Sulfide-1.4; Silicate-1.8.

Because the content of the nonmetallic impurity of sulphur is low, so what obtain is the high-quality steel.

Example 23

The production method of steel commonly used realizes in 100 tons of casting ladle.Situation is similar to example 18.

Same material and consumption thereof have been used.Difference is the consumption of carbide of calcium.

With quantity that a alumina-bearing material adds the carbide of calcium of ladle and lime together is that ratio in aluminium in lime and the alumina-bearing material and carbide of calcium should be 5.0: 0.6: 1.5 mutually and selects for use.

The total flow of lime, alumina-bearing material and carbide of calcium is 0.6 ton.

With quantity that another part alumina-bearing material adds the carbide of calcium of ladle is that ratio in aluminium in the alumina-bearing material and carbide of calcium should be 1.2: 3.0 mutually and selects for use.This moment, the consumption of carbide of calcium was 0.4 ton.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that draws has following chemical constitution (quality %): C-0.12; Si-0.27; Mn-0.55; S-0.005; P-0.014; Al-0.026; Fe-all the other.

The manganese recovery ratio of this moment is 97.6%, desulfurization degree-77.4%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.5; Sulfide-1.7; Silicate-2.0.

Because the content of the nonmetallic impurity of sulphur is low, so what obtain is the high-quality steel.

Example 24

The production method of steel commonly used realizes that situation is similar to example 18 in 100 tons of casting ladle.

Same material and consumption thereof have been used.Difference is the consumption of carbide of calcium.

With quantity that a alumina-bearing material adds the carbide of calcium of ladle and lime together is that ratio in aluminium in lime and the alumina-bearing material and carbide of calcium should be 5.0: 0.5: 2.0 mutually and selects for use.

The total flow of lime, alumina-bearing material and carbide of calcium is 0.6 ton.

With quantity that another part alumina-bearing material adds the carbide of calcium of ladle is that ratio in aluminium in the alumina-bearing material and carbide of calcium should be 1.1: 3.0 mutually and selects for use.

The consumption of carbide at this moment is 0.45 ton.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.09; Si-0.21; Mn-0.52; S-0.004; P-0.017; Al-0.023; Fe-all the other.

At this moment manganese recovery ratio is 94.1%, and desulfurization degree is-81.2%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.5; Sulfide-1.2; Silicate-1.7.

Because the content of sulphur and nonmetallic impurity is low, what therefore obtain is the high-quality steel.

Example 25

The production method of steel commonly used realizes that situation is similar to example 18 in 100 tons of casting ladle.

Same material and consumption thereof have been used.Difference is the consumption of carbide of calcium.

With quantity that a alumina-bearing material adds the carbide of calcium of ladle and lime together is that ratio in aluminium in lime and the alumina-bearing material and carbide of calcium should be 5.0: 0.5: 1.7 mutually and selects and is chosen to be.

The total flow of lime, alumina-bearing material and carbide of calcium is 0.6 ton.

The quantity of carbide of calcium that adds ladle with another part alumina-bearing material also is 0.45 ton as example 24.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.12; Si-0.22; Mn-0.50; S-0.005; P-0.014; Al-0.020; Fe-all the other.

The manganese recovery ratio of this moment is 93.9%, desulfurization degree-77.3.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-1.7; Sulfide-1.4; Silicate-1.9.

Because the content of sulphur and nonmetallic impurity is low, what therefore obtain is the high-quality steel.

Make comparisons usefulness of example 26()

The production method of steel commonly used is to realize by existing technology (SUA, 1044641) in 350 tons of casting ladle.

When whole carbon element work in-process all go out after ladle, in ladle, add 4.2 tons of low-phosphorous manganese slags in the iron alloys production, (weight %) is as follows for its chemical constitution: SiO ₂-25; MnO-65; CaO-5.5; FeO-0.2; Al ₂O ₃-2.2; MgO-2.3; P-0.010; All the other are other impurity; 3.3 ton lime, its CaO content is 90%, and all the other are other incidental impurities and 0.72 ton of alumina-bearing material, and 86% aluminium is wherein arranged, and all the other are other incidental impurities.

After this, the oxygen of haveing broken up for 15 seconds on the molten surface, blowing argon gas 10 minutes on the molten metal then.

The casting of Finished Steel, rolling all similar to example 1 with metallographic examination.

The steel that obtains has following chemical constitution (quality %): C-0.12; Si-0.24; Mn-0.50; S-0.018; P-0.020; Al-0.021; Fe-all the other.

The manganese recovery ratio-70.4% of this moment, desulfurization degree-21.2%.

The nonmetallic impurity dustiness (level) of steel is: oxide compound-3.2; Sulfide-3.6; Silicate-2.9.

Because the content height of sulphur and nonmetallic impurity, what therefore obtain is non-prime steel.

Mode standard

The rate of recovery % of X chromium

From above example of enumerating and table, as can be seen, utilize the method for recommending to make desulfurization degree, manganese recovery ratio increase the dustiness that manyfold also significantly reduces nonmetallic impurity.All these is to carry out under the condition that reduces steel production method cost commonly used.

The present invention can be used for the production of converter, open hearth and electric furnace Common Steels.

The present invention is used for steel ladle production effect the best of manganese steel.

Claims (8)

1, the production method of normal steels, be included in melting carbon element work in-process in the furnace, be injected into ladle, add sweetening material, reductive agent in the ladle and contain alloying element through heat treated oxidation material in advance, be characterized in reductive agent is added ladle in batches, portion is to go out in the ladle to be no more than in 1/3 process to quality at the carbon element work in-process with sweetening material to add, and another part is with adding ladle together before the carbon element work in-process have gone out through heat treated oxidation material in advance.

2, according to claim 1, the characteristics of normal steels production method are, will contain the conduct of manganese oxidation material through heat treated oxidation material use in advance through heat treated in advance under 900-1250 ℃ of temperature.

3, according to claim 2, the characteristics of present method are, are to add ladle in neutral air-flow through the heat treated manganese oxidation material that contains in advance, and will heat this moment to molten metal.

4, according to claim 1, the characteristics of present method are, slag former is used as sweetening material, and it be should be (1.0-1.1) in slag former mutually with the ratio that adds first part of reductive agent: (0.2-0.3) selected amount adds ladle.

5, according to claim 1, the characteristics of present method are, will replenish the adding sweetening material simultaneously when adding another part reductive agent.

6, according to claim 5, the characteristics of present method are, rhombspar is replenished the sweetening material that adds ladle simultaneously as another part reductive agent use, and its quantity is selected in rhombspar and its 0.8-1.2 ratio that adds reductive agent simultaneously.

7, according to claim 1 or 4 or 5 or 6, the characteristics of present method are, alumina-bearing material is used as reductive agent.

8, according to claim 1 and 5, the characteristics of present method are, carbide of calcium is used as sweetening material, at this moment, carbide of calcium adds with a alumina-bearing material and lime, its quantity should be (4.0-5.0) mutually in the aluminium in lime and the alumina-bearing material and the ratio of carbide of calcium: (0.3-0.6): (1.5-2.0) select for use, and the quantity of the carbide of calcium that replenish to add simultaneously with another part alumina-bearing material should should be (1.0-1.2) with the ratio of carbide of calcium mutually in the aluminium in the alumina-bearing material: (2.5-3.6) select for use.