CN111254345A - Low-titanium low-microelement casting molten iron for wind power and preparation method thereof - Google Patents
Low-titanium low-microelement casting molten iron for wind power and preparation method thereof Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C37/00—Cast-iron alloys
- C22C37/06—Cast-iron alloys containing chromium
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- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
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- C21B13/0006—Making spongy iron or liquid steel, by direct processes obtaining iron or steel in a molten state
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/0066—Preliminary conditioning of the solid carbonaceous reductant
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/02—Dephosphorising or desulfurising
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0006—Adding metallic additives
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- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0056—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using cored wires
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
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- C22C37/10—Cast-iron alloys containing aluminium or silicon
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Abstract
The invention provides a production method of low-titanium low-trace-element cast molten iron for wind power. The molten iron comprises: ti is less than or equal to 0.010 percent, Cr + V + Mo + Sn + Sb + Pb + Bi + Te + As + B + Al is less than or equal to 0.040 percent. The preparation method is carried out by adopting a smelting reduction method. The method determines the maximum limit value of the content of more than ten trace elements suitable for the molten iron of the wind power equipment, and particularly realizes the accurate control of the content of key trace elements such as sulfur, phosphorus, titanium and the like. The method optimizes the mode of a key technical system in the whole smelting process, cancels the processes of high energy consumption, high pollution material agglomeration and pelletizing such as coking, sintering, pelletizing and the like, directly adopts mineral powder and common coal powder for smelting, does not need a concentrate method, can produce by adopting common ores, improves the smelting efficiency, improves the utilization rate of subsequent processes, reduces the energy consumption and protects the environment.
Description
Technical Field
Embodiments of the present disclosure relate generally to the field of steel smelting, and more particularly, to a cast molten iron for wind power that directly produces low-titanium low-trace elements and a method for preparing the same.
Background
Wind energy is a clean renewable energy source, the total amount of the global wind energy is 10 times larger than the total amount of the permanent energy which can be developed and utilized on the earth, the global wind energy is the most promising energy source in the renewable energy sources, the world is emphasized, the wind energy reserves of China are also large and wide in distribution, the wind energy reserves on the land only have about 2.53 hundred million kilowatts, and the total wind energy reaches 10 hundred million kilowatts. The new energy strategy in China sets the key point for the vigorous development of wind power generation. The casting is an important part of wind power generation equipment, the castings on the wind power generation equipment are all ferrite-based nodular iron castings with high requirements, and the casting mainly comprises components such as a hub provided with blades, a gear box body, a base, a bearing seat and the like, wherein the hub is a core part in the casting.
Wind power castings are in severe operating environments, operate at high altitudes of dozens of meters to more than one hundred meters all year round, are subjected to various extremely severe weather and complex wind alternating loads, and are in service for 20 years at-20 ℃ or even-40 ℃. Therefore, the requirement on the quality performance index of the casting is higher, besides the conventional performance index, the requirement on the low-temperature impact performance index is also met, and particularly, the higher requirement on the anti-spheroidization element Ti is provided.
Production and smelting equipment for domestic molten iron for wind power castings selects effective volume of 200-500 m3The small blast furnace of (1). The long-term smelting of the large-volume blast furnace easily causes the fluctuation of the furnace conditions, reduces the efficiency of the blast furnace, has large fluctuation of the furnace conditions and is difficult to produce qualified products stably.
The molten iron for smelting wind power castings is required to be prepared from high-quality raw fuels, the requirements of charging coke (including coal injection) and impurities of sulfur, phosphorus, manganese, titanium and other trace elements in ores for smelting the molten iron for the wind power castings are met, and meanwhile, the molten iron for smelting the wind power castings is required to be dephosphorized by an external furnace treatment and an oxidation method, so that the cost is high and the pollution is serious.
Disclosure of Invention
The invention aims to provide wind power casting molten iron for directly producing low-titanium low-trace elements and a production method thereof.
According to the embodiment of the disclosure, the cast molten iron for wind power with low titanium and low trace elements is provided, high-energy-consumption and high-pollution pelletizing processes such as coking, sintering and pelletizing are cancelled, mineral powder and common pulverized coal are directly adopted for smelting, a concentrate method is not adopted, and the molten iron has the following chemical components and important percentage requirements: ti is less than or equal to 0.010 percent, Cr + V + Mo + Sn + Sb + Pb + Bi + Te + As + B + Al is less than or equal to 0.040 percent.
Further, the molten iron comprises the following chemical components in percentage by weight: c: 3.7-4.1%, Si: 0.0001-0.0012%, P: 0.010-0.018%, S: 0.015 to 0.025, Ti: 0.0001-0.010%, Cr: 0.0001-0.010, V: 0.0001-0.010%, Mo: 0.005-0.030, Sn: 0.0001-0.005%, Sb: 0.0005 to 0.003%, Pb: 0.0005 to 0.0011%, Bi: 0.0001-0.0005%, Te: 0.0002-0.0006%, As: 0.0002-0.0010%, B: 0.0001-0.0010%, Al: 0.002-0.010% and the balance Fe.
Further, the molten iron comprises the following chemical components in percentage by weight: less than or equal to 0.005 percent of Ti, and less than or equal to 0.02 percent of Cr + V + Mo + Sn + Sb + Pb + Bi + Te + As + B + Al.
Further, there is provided a method of directly producing the above cast molten iron, comprising the steps of: the high-energy-consumption and high-pollution pelletizing process such as coking, sintering, pelletizing and the like is cancelled, mineral powder and common coal powder are directly adopted for smelting, a concentrate method is not adopted, common mineral powder is adopted, a melting reduction process is adopted, oxygen-enriched hot air with the temperature of more than 1080 ℃ and the oxygen-enriched content controlled within 40 +/-2 percent is sprayed into a melting reaction furnace through an oxygen-enriched spray gun (1) at the speed of 300 +/-50 m/s, and the air quantity is controlled at 140000 plus materials, 180000Nm and 180000Nm3(ii) a The phosphorus content in the ore entering the furnace is strictly controlled to be less than 0.1 percent, the granularity of the ore powder is strictly controlled to be less than 8mm, reasonable dolomite and quicklime powder are added and heated to be more than 450 ℃, inert or reducing gas is sprayed into a reduction zone (6) of a smelting reduction reaction furnace through an ore powder spray gun (2), the spraying speed is more than 50m/s, the inert or reducing gas is sprayed into molten iron through a slag layer and reduced by residual carbon elements in the molten iron, meanwhile, the granularity of the pulverized coal is strictly controlled to be less than 6mm, the moisture content of the pulverized coal is less than 3 percent, the temperature is more than or equal to 85 ℃, inert or reducing gas is sprayed into the reduction zone (6) of the smelting reduction reaction furnace through a pulverized coal spray gun (3), the inert or reducing gas is sprayed into the molten iron through the slag layer, the spraying speed is more than 50 m/s.
Further, the reducing gas consists essentially of CxHy、H2And one or more of CO.
Furthermore, reasonable dolomite and quicklime powder are added, the proportion of the mixture is up to the slag alkalinity target of 1.25 +/-0.05, and quaternary alkalinity (CaO + MgO)/(Al) is adopted2O3+SiO2) And (4) calculating.
Further, when the generated slag reaches a certain amount, the reaction furnace is removed through a slag hole (4), and a communicating vessel type slag-free tapping process tapping chamber (5) is adopted to tap iron into a ladle.
Further, ensure the gas in the slagThe proportion of the components is as follows: (H)2+CO)/(CO2+H2O) is less than 10, and the controlled slag amount is more than 0.42 t/tFe.
And further, performing magnesium wire feeding desulfurization in a ladle, simultaneously performing double-hole wire feeding by adopting a double wire feeding machine, standing for 5 minutes after desulfurization, and performing sampling inspection to control the residual magnesium content to be 0.030% -0.045%.
Further, the magnesium wire is a high-magnesium core-spun wire with the diameter of phi 13mm, the wire is wrapped by 0.30mm cold rolling strip steel, the linear density is 380-400 g/m, the weight of the content is 220g/m, the content of passivated magnesium in the content is 28-40%, the content of silicon is 4-6%, the content of graphite is 8-12%, the content of calcium oxide is 45-55%, the sum of all components in the content is 100%, and the adding amount of core wires is 0.82% of the mass of molten iron. The invention has the advantages and effects that:
the invention can produce the casting molten iron for wind power which completely meets the quality requirement of low titanium and low trace elements at the present stage by adopting the common mineral powder and the coal powder, cancels the processes with heavy pollution and high energy consumption such as sintering, coking, pelletizing and the like, and fills the blank in the technical field of producing the special molten iron for wind power equipment by the smelting reduction method in China.
The invention optimizes the components and the content of the special molten iron for the wind power equipment, and the main components except Fe in the molten iron are C, Si, Mn, P and S. The wind power casting is also controlled by the components of V, Cr, Sn, Pb, Bi, Mo, Sb, Cu, Al, Ni, B and other trace elements, especially Ti. Repeated experiments and corrections are carried out on the mechanical property, the metallographic structure and the element components of the molten iron product, the maximum limit value of the content of more than ten trace elements in the molten iron suitable for the wind power equipment is determined, and especially the accurate control on the content of the key trace elements such as sulfur, phosphorus, titanium and the like is realized. The mode of a key technical system of the whole smelting process is optimized, the smelting efficiency is improved, the utilization rate of the subsequent flow is also improved, the energy consumption is reduced, and the environment is protected.
The invention optimizes the technological parameters of the smelting reduction, determines the technological technology suitable for producing the special molten iron for the wind power equipment, and particularly optimizes the main requirements of hot air temperature, oxygen content, air quantity, speed, ore, the proportion of the flux and the quantity of the pulverized coal, so that the smelted molten iron has more accurate control on components compared with the traditional technology, saves energy consumption, is simple and direct to operate and has stable technology.
The proper mixture of dolomite and quicklime is adopted to ensure the alkalinity and the fluidity of the slag and the control of impurities and trace elements in the smelting process. The slag-free tapping process ensures the purity of iron and does not waste molten iron. The invention provides the proportion of gas in the slag, and the Ti removal effect is well ensured by controlling the proportion. And the magnesium wire with specific components is adopted for desulfurization, so that the removal of impurities in the molten iron is also ensured.
In conclusion, the molten iron for wind power casting with low titanium and low micro-roundness is produced by utilizing melting reduction, the process is simple, the quality of the molten iron for wind power casting is guaranteed after technological parameters are optimized, and special impurity removal and component adjustment treatment on the molten iron are not needed in the using process.
It should be understood that the statements herein reciting aspects are not intended to limit the critical or essential features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become apparent from the following description.
Drawings
The above and other features, advantages and aspects of various embodiments of the present disclosure will become more apparent by referring to the following detailed description when taken in conjunction with the accompanying drawings. In the drawings, like or similar reference characters designate like or similar elements, and wherein:
FIG. 1 is a schematic view showing a structure of a smelting reduction furnace according to the present invention;
figure 2 shows a material flow diagram of the present invention.
1-an oxygen-enriched spray gun; 2-mineral powder spray gun; 3-a pulverized coal spray gun; 4-a slag hole; 5-a tapping chamber; 6-reduction zone; a 7-oxidation zone;
Detailed Description
To make the objects, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be described clearly and completely with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are some, but not all embodiments of the present disclosure. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.
In addition, the term "and/or" herein is only one kind of association relationship describing an associated object, and means that there may be three kinds of relationships, for example, a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.
A method for producing molten iron for casting provided by an embodiment of the present invention will be described with reference to fig. 1.
Preparing a main raw material and a reducing agent;
the main raw material is iron oxide ore powder, wherein when the ore raw material is selected, the phosphorus content in the ore is strictly controlled to be less than 0.1%, the granularity of the ore powder is strictly controlled to be less than 8mm, and the grade of the iron ore is more than 55%. Common imported ore or domestic concentrate powder is adopted.
In some embodiments, dolomite and limestone are crushed and uniformly mixed with the iron oxide ore powder according to process parameters to obtain the main raw material. The weight ratio of the dolomite, the limestone and the iron oxide ore powder is adjusted to ensure that the alkalinity R of the obtained smelting slag is 1.25, so that the contents of titanium and trace elements in the molten iron can be effectively controlled. Wherein, the alkalinity R is calculated according to quaternary alkalinity, and R is (wCaO + wMgO)/(wSiO)2+wAl2O3) Respectively are CaO, MgO and SiO2、Al2O3Content (%, w). Preheating the main raw materials to above 450 ℃ by a mineral powder heating system.
The reducing agent is anthracite and/or bituminous coal powder. Anthracite and bituminous coal are transported to a raw coal bunker through a stock ground, and are transported to a crushing and drying system from the raw coal bunker through a belt, so that coal powder with the particle size of less than or equal to 6mm, the moisture of less than or equal to 3 percent and the temperature of more than or equal to 85 ℃ is obtained as a reducing agent. The production cost is low because the use of expensive coke is not required. The pulverized coal includes bituminous coal (also referred to as gas coal) and anthracite coal, and the proportion of the bituminous coal is required to be less than 50 wt%.
In some embodiments, the content of the trace elements in the molten iron can be effectively controlled by adjusting the rational carbon ratio (C/O molar ratio) of the reducing agent to the main raw material to be 0.8 to 1.3, for example, 1.0.
The main raw material, the reducing agent and the oxygen-enriched air are input into a melting reduction furnace for reduction reaction.
Inert gases or reducing gases are respectively sprayed into a reduction area (6) of the smelting reduction reaction furnace through a mineral powder spray gun (2) and sprayed into molten iron through a slag layer to be reduced by residual carbon elements in the molten iron. At the same time
The main raw materials are sprayed into an iron slag molten pool of the smelting reduction furnace through a mineral powder spray gun (2) positioned in the middle of the smelting reduction furnace. Inert gases or reducing gases are respectively sprayed into a reduction area (6) of the smelting reduction reaction furnace through a mineral powder spray gun (2) and sprayed into molten iron through a slag layer to be reduced by residual carbon elements in the molten iron. The blowing speed is more than 50 m/s. The gas amount of the mineral powder spray gun (2) for conveying is 8000-11000 Nm3H is used as the reference value. The carrier gas used by the mineral powder spray gun can be inert or reducing gas.
In some embodiments, dolomite and limestone ore fines may also be injected into the smelting reduction furnace as an auxiliary material separately through an auxiliary material lance located in the middle of the smelting reduction furnace. The carrier gas used by the auxiliary material spray gun can be inert gas or coke oven gas, methane and H2And the like.
And spraying the reducing agent into an iron slag molten pool of the smelting reduction furnace from a coal powder spray gun positioned in the middle of the smelting reduction furnace.
In some embodiments, the amount of the conveying gas of the pulverized coal spray gun is 1500-4000 Nm3H is used as the reference value. The carrier gas used by the pulverized coal injection lance can be inert or reducing gas. The blowing speed is more than 50m/s, the blowing amount of the coal dust is more than 600kg/t molten iron, and the proportion of the bituminous coal in the coal dust is less than 50 wt%, so that carbon is supplemented for the molten iron.
Oxygen-enriched air is blown into the smelting reduction furnace from an oxygen lance positioned at the top of the smelting reduction furnace. The volume percentage of oxygen in the oxygen-enriched air is 40%, the temperature of the oxygen-enriched air is 1000-1100 ℃, and the input speed of the oxygen-enriched air is 300 +/-50 Nm3Min, the air volume is controlled at 140000 and 180000Nm3/h。
It should be noted that the above steps: the main raw material, the reducing agent and the oxygen-enriched air are respectively injected into the smelting reduction reaction furnace through corresponding injection systems (a mineral powder injection gun, a coal powder injection gun and an oxygen gun) and can be simultaneously carried out, and sequentially or alternatively carried out. In the embodiment of the present disclosure, the above steps are performed simultaneously.
The main raw material and the reducing agent are respectively sprayed into an iron slag melting pool of the smelting reduction reaction furnace through corresponding spraying systems (a mineral powder spray gun and a coal powder spray gun), the temperature of the melting pool is controlled within the range of 1450 and 1550 ℃, the stability of the spraying system is ensured, the reaction of the melting pool is stable, and the pressure in the smelting reduction reaction furnace is ensured to be kept at 60-100 kPa.
In some embodiments, oxygen-enriched air is blown into the smelting reduction furnace from an oxygen lance positioned at the top of the smelting reduction furnace, and a weakly oxidizing atmosphere is controlled and maintained in the smelting reduction furnace due to the 35% to 55% oxygen contained therein. The temperature of the oxygen-enriched air is 1000-1100 ℃, so the reducing agent coal powder is sprayed into the smelting reduction furnace to burn and release heat, and a heat source is provided for the reduction reaction in the smelting reduction furnace. Meanwhile, based on the addition amount and the addition speed of the reducing agent, the addition speed of the oxygen-enriched air and the oxygen content, the combustion of the reducing agent coal powder in the melting reduction furnace is partial combustion to generate CO gas, and the CO gas can participate in the reduction reaction. Therefore, the reducing agent coal powder is sprayed into the melting reduction furnace to burn and release heat, so that the temperature in the melting reduction furnace is controlled within the range of 1450-. And CO gas escaping from the molten pool and high-temperature oxygen-enriched air sprayed from the top of the furnace are subjected to secondary combustion to release heat to maintain the high temperature in the furnace, a part of heat is brought back to the molten pool by splashed slag in strong slag iron splashing stirring, the heat generated by the secondary combustion at the upper part is transferred to the molten pool, and the sprayed mineral powder and coal powder are melted.
In some embodiments, the carrier gas used by the ore powder spray gun and the reducing agent spray gun can also be a mixed gas of inert gas and air or a mixed gas of reducing gas and air. The oxidizability of the slag bath can be regulated and controlled by regulating the proportion of the inert gas and the air,the FeO content of the slag is ensured to reach 5-10%, and the slag has certain dephosphorization capability. Simultaneously, the gas component proportion in the slag is ensured: (H)2+CO)/(CO2+H2O) is less than 8, and the slag amount is controlled to be more than 0.42t/tFe, so that the titanium removal is ensured.
The reducing gas mainly comprises CxHy and H2And CO, which reacts with FeO dissolved in the molten iron and the slag liquid to generate liquid molten iron. The slag alkalinity was controlled to 1.25 ± 0.05. The temperature of the oxygen-enriched hot air is higher than 1080 ℃, and the oxygen-enriched content is 40 +/-2%.
In some embodiments, the intermediate portion of the smelting reduction furnace is defined as about 1/2 points between the hearth and the roof (of course, it should be understood that the term "1/2" is not strictly limited, for example, in terms of height of the smelting reduction furnace, ranging from 2/5 to 2/5). One ore powder spray gun can be arranged, or a plurality of ore powder spray guns can be arranged; one or more pulverized coal spray guns can be arranged; and the mineral powder spray guns and the coal powder spray guns are alternately arranged, so that the main raw materials and the reducing agent can be uniformly mixed. The number of the ore powder injection lances and the number of the coal injection lances may be appropriately selected by those skilled in the art according to actual conditions, and is not limited herein.
Tapping molten iron in the molten pool through the communicating vessel.
And (4) calculating the amount of molten iron in the molten pool, and when the amount of molten iron meets the storage requirement, increasing the pressure in the furnace through the pressure adjustment in the furnace, namely tapping through a communicating vessel type slag-free tapping process.
When the generated slag reaches a certain amount, the reaction furnace is removed through a slag hole (4), tapping is carried out in a tapping chamber (5) by adopting a communicating vessel type slag-free tapping process, and a sample is taken for analysis after tapping.
The magnesium wire is fed into a ladle for desulfurization, a double-wire feeder is adopted for feeding wires in double holes simultaneously, the magnesium wire is a high-magnesium core-spun wire with the diameter of phi 13mm, the core-spun wire is wrapped by 0.30mm cold-rolled strip steel, the linear density is 380-400 g/m, the weight of contents is 220g/m, the content of passivated magnesium in the contents is 28-40%, the content of silicon is 4-6%, the content of graphite is 8-12%, the content of calcium oxide is 45-55%, the sum of all components in the contents is 100%, and the adding amount of core wires is 0.82% of the mass of molten iron. And (5) sampling and checking after desulfurization is finished.
The wire feeding amount is calculated according to the sulfur content, the wire feeding addition amount is required to be accurate, molten iron splashing in the desulfurization process is avoided, the temperature loss is reduced, the treatment bag is accurately and quickly positioned, and the molten iron retention time is reduced. Standing for 5 minutes after desulfurization, sampling and checking, wherein the residual magnesium content is controlled to be 0.030% -0.045%. The molten iron comprises the following components:
TABLE 1 examples 1 to 3 chemical compositions and weight percentages (unit: wt%)
| C | Si | P | S | Ti | |
| Example 1 | 3.92 | 0.0008 | 0.016 | 0.113 | 0.007 |
| Example 2 | 3.98 | 0.0009 | 0.017 | 0.104 | 0.008 |
| Example 3 | 3.97 | 0.0007 | 0.015 | 0.120 | 0.007 |
TABLE 1 examples 1 to 3 chemical components and weight percentages (unit: wt%)
| Cr | V | Mo | Sn | Sb | Pb | Bi | Te | As | B | Al | |
| Example 1 | 0.011 | 0.010 | 0.006 | 0.004 | 0.001 | 0.001 | 0.0004 | 0.0003 | 0.0014 | 0.001 | 0.013 |
| Example 2 | 0.010 | 0.012 | 0.008 | 0.004 | 0.002 | 0.001 | 0.0003 | 0.0004 | 0.0014 | 0.001 | 0.014 |
| Example 3 | 0.012 | 0.011 | 0.007 | 0.003 | 0.001 | 0.001 | 0.0003 | 0.0005 | 0.0015 | 0.001 | 0.013 |
From the component inspection of tables 1 and 2, the molten iron produced by using the common mineral powder and the non-coking coal powder by adopting the melting reduction process has stable components, meets the requirement of the cast molten iron for wind power with low titanium and low trace elements, is superior to the molten iron for steelmaking smelted by a common blast furnace method, reduces pollutant emission because a material granulation sintering process is not adopted, and the product completely meets the component requirements of the molten iron for casting of wind power equipment and the like.
According to the embodiment of the disclosure, the following technical effects are achieved: the main components of the nodular iron except Fe are C, Si, Mn, P, S and Mg. The wind power casting is also controlled by the components of V, Cr, Sn, Pb, Bi, Mo, Sb, Cu, Al, Ni, B and other trace elements, especially Ti.
Repeated experiments and corrections are carried out on the mechanical property, the metallographic structure and the element components of the molten iron product, the maximum limit value of the content of more than ten trace elements in the molten iron suitable for the wind power equipment is determined, and especially the accurate control on the content of the key trace elements such as sulfur, phosphorus, titanium and the like is realized. The key technical innovation of the whole smelting process is to carry out solidification in a regulation and system mode. The common mineral powder can be adopted to produce the cast iron which completely meets the quality requirement of high-quality cast iron at the present stage; and does not need to use expensive coke, and the production and operation cost is low.
In the description of the present application, the description of the terms "one embodiment," "some embodiments," etc. means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. The low-titanium low-microelement foundry molten iron for wind power is characterized in that high-energy-consumption and high-pollution pelletizing processes such as coking, sintering and pelletizing are cancelled, mineral powder and common coal powder are directly adopted for smelting, a concentrate method is not adopted, and the molten iron comprises the following chemical components in percentage by weight: ti is less than or equal to 0.010 percent, Cr + V + Mo + Sn + Sb + Pb + Bi + Te + As + B + Al is less than or equal to 0.040 percent.
2. The cast molten iron of claim 1, wherein the molten iron comprises the following chemical components in percentage by weight: c: 3.7-4.1%, Si: 0.0001-0.0012%, P: 0.010-0.018%, S: 0.015 to 0.025, Ti: 0.0001-0.010%, Cr: 0.0001-0.010, V: 0.0001-0.010%, Mo: 0.005-0.030, Sn: 0.0001-0.005%, Sb: 0.0005 to 0.003%, Pb: 0.0005 to 0.0011%, Bi: 0.0001-0.0005%, Te: 0.0002-0.0006%, As: 0.0002-0.0010%, B: 0.0001-0.0010%, Al: 0.002-0.010% and the balance Fe.
3. The cast molten iron of claim 2, wherein the molten iron comprises the following chemical components in percentage by weight: less than or equal to 0.005 percent of Ti, and less than or equal to 0.02 percent of Cr + V + Mo + Sn + Sb + Pb + Bi + Te + As + B + Al.
4. A method of directly producing the foundry molten iron of claims 1 to 3, which comprises the steps of: the high-energy-consumption and high-pollution pelletizing process such as coking, sintering, pelletizing and the like is cancelled, mineral powder and common coal powder are directly adopted for smelting, a concentrate method is not adopted, common mineral powder is adopted, a melting reduction process is adopted, oxygen-enriched hot air with the temperature of more than 1080 ℃ and the oxygen-enriched content controlled within 40 +/-2 percent is sprayed into a melting reaction furnace through an oxygen-enriched spray gun (1) at the speed of 300 +/-50 m/s, and the air quantity is controlled at 140000 plus materials, 180000Nm and 180000Nm3(ii) a Strictly controlling the phosphorus content in the ore entering the furnace to be less than 0.1 percent and strictly controlling the granularity of the mineral powderLess than 8mm, adding reasonable dolomite and quicklime powder, heating to more than 450 ℃, spraying inert or reducing gas into a reduction area (6) of the smelting reduction reaction furnace through a mineral powder spray gun (2), spraying the inert or reducing gas at a spraying speed of more than 50m/s, spraying the inert or reducing gas into molten iron through a slag layer, reducing residual carbon elements in the molten iron, strictly controlling the granularity of the coal powder to be less than 6mm, controlling the moisture content of the coal powder to be less than 3 percent and the temperature to be more than or equal to 85 ℃, spraying the inert or reducing gas into the reduction area (6) of the smelting reduction reaction furnace through a coal powder spray gun (3), spraying the inert or reducing gas into the molten iron through the slag layer at a spraying speed of more than 50m/s, spraying the coal powder at a spraying amount of more than 600 kg.
5. The method of casting molten iron according to claim 4, wherein the reducing gas consists essentially of CxHy、H2And one or more of CO.
6. The method for casting molten iron according to claim 5, wherein reasonable dolomite and quicklime powder are added in a proportion to achieve a slag basicity target of 1.25 ± 0.05, and quaternary basicity ═ CaO + MgO)/(Al is used2O3+SiO2) And (4) calculating.
7. The method for casting molten iron according to claim 6, wherein when the amount of the generated slag reaches a certain amount, the reaction furnace is removed through the slag hole (4), and the tapping chamber (5) is tapped into the ladle by a communicating vessel type slag-free tapping process.
8. The method of casting molten iron according to claim 7, wherein the ratio of gas components in the slag is ensured to be: (H)2+CO)/(CO2+H2O) is less than 10, and the controlled slag amount is more than 0.42 t/tFe.
9. The method of casting molten iron according to claim 8, further comprising performing magnesium wire feeding desulfurization in the ladle using a twin wire feeder while feeding wires through two holes, standing for 5 minutes after desulfurization, and performing sampling inspection while controlling the amount of residual magnesium to 0.010% to 0.020%.
10. The method for casting molten iron according to claim 9, wherein the magnesium wire is a high-magnesium cored wire with a diameter of phi 13mm, the wire is wrapped with 0.30mm cold-rolled strip steel, the linear density is 380-400 g/m, the weight of the content is 220g/m, the content of passivated magnesium in the content is 28-40%, the content of silicon is 4-6%, graphite is 8-12%, calcium oxide is 45-55%, the sum of the components in the content is 100%, and the adding amount of the core wire is 0.82% of the mass of the molten iron.
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|---|---|---|---|---|
| CN112011721A (en) * | 2020-08-26 | 2020-12-01 | 内蒙古赛思普科技有限公司 | Pig iron for directly producing low-silicon low-titanium low-trace-element nodular cast iron and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1176310A (en) * | 1995-07-19 | 1998-03-18 | 霍戈文斯·斯塔尔公司 | Method and apparatus for producing pig iron by smelting reduction and method of obtaining such plant |
| WO1999016911A1 (en) * | 1997-09-26 | 1999-04-08 | Technological Resources Pty. Ltd. | Direct smelting process for producing metals from metal oxides |
| CN110408737A (en) * | 2019-08-14 | 2019-11-05 | 临沂玫德庚辰金属材料有限公司 | A kind of dedicated pig iron making process of wind power casting |
-
2020
- 2020-02-26 CN CN202010118713.3A patent/CN111254345A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1176310A (en) * | 1995-07-19 | 1998-03-18 | 霍戈文斯·斯塔尔公司 | Method and apparatus for producing pig iron by smelting reduction and method of obtaining such plant |
| WO1999016911A1 (en) * | 1997-09-26 | 1999-04-08 | Technological Resources Pty. Ltd. | Direct smelting process for producing metals from metal oxides |
| CN110408737A (en) * | 2019-08-14 | 2019-11-05 | 临沂玫德庚辰金属材料有限公司 | A kind of dedicated pig iron making process of wind power casting |
Non-Patent Citations (1)
| Title |
|---|
| 朱苗勇: "《现代冶金工艺学--钢铁冶金卷（第2版）》", 13 December 2016, 《现代冶金工艺学--钢铁冶金卷（第2版）》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112011721A (en) * | 2020-08-26 | 2020-12-01 | 内蒙古赛思普科技有限公司 | Pig iron for directly producing low-silicon low-titanium low-trace-element nodular cast iron and preparation method thereof |
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