CN110093545B - Method for preparing vanadium-nitrogen alloy by rotary hearth furnace - Google Patents
Method for preparing vanadium-nitrogen alloy by rotary hearth furnace Download PDFInfo
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- CN110093545B CN110093545B CN201910417256.5A CN201910417256A CN110093545B CN 110093545 B CN110093545 B CN 110093545B CN 201910417256 A CN201910417256 A CN 201910417256A CN 110093545 B CN110093545 B CN 110093545B
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/05—Mixtures of metal powder with non-metallic powder
- C22C1/051—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor
- C22C1/053—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor with in situ formation of hard compounds
- C22C1/055—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor with in situ formation of hard compounds using carbon
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/05—Mixtures of metal powder with non-metallic powder
- C22C1/051—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor
- C22C1/053—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor with in situ formation of hard compounds
- C22C1/056—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor with in situ formation of hard compounds using gas
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
- C22C29/16—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on nitrides
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C35/00—Master alloys for iron or steel
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Abstract
The invention provides a method for preparing vanadium-nitrogen alloy by a rotary hearth furnace, belonging to the field of material preparation. The method comprises the following steps: mixing and crushing vanadium oxide and carbonaceous reducing agent, and pressing the mixture into balls under the action of a binder to obtain ball materials; and (3) putting the ball material into a rotary hearth furnace, introducing nitrogen into the rotary hearth furnace, carrying out high-temperature reaction, and cooling to obtain the vanadium-nitrogen alloy. According to the invention, the vanadium-nitrogen alloy is prepared by using the rotary hearth furnace, three working areas (the low-temperature preheating area, the high-temperature reducing area and the cooling area) of the rotary hearth furnace are fully utilized, compared with the vanadium-nitrogen alloy prepared by reducing the traditional blast furnace, the vanadium-nitrogen alloy prepared by using the rotary hearth furnace has less heat loss, and has the advantages of simple process, strong operability and short production period.
Description
Technical Field
The invention relates to the technical field of material preparation, in particular to a method for preparing vanadium-nitrogen alloy by a rotary hearth furnace.
Background
The vanadium nitride alloy is a novel alloy additive, and can replace ferrovanadium to be used for producing microalloyed steel. The vanadium nitride alloy added into the steel can improve the comprehensive mechanical properties of the steel, such as strength, toughness, ductility, thermal fatigue resistance and the like, and enables the steel to have good weldability. Under the condition of achieving the same strength, the vanadium nitride is added, so that the adding amount of vanadium is saved by 30-40%, and the cost is further reduced. The vanadium nitride alloy can be used in structural steel, tool steel, pipeline steel, steel bar and cast iron. The vanadium nitride alloy can be applied to high-strength low-alloy steel to simultaneously carry out effective vanadium and nitrogen microalloying, promote the precipitation of carbon, vanadium and nitrogen compounds in the steel and more effectively play roles in sedimentation strengthening and grain refinement.
At present, vanadium-nitrogen alloy is produced by adding a reducing agent graphite into vanadium oxide (vanadium pentoxide, vanadium tetraoxide, vanadium trioxide or a mixture of the three) to be pressed into blocks, placing the blocks in a blast furnace by powder metallurgy, and carrying out reduction and nitridation reaction in a high-temperature nitrogen atmosphere. The theoretical temperature of reduction and nitridation reaction of vanadium is determined to be higher than 1250 ℃ by the property of vanadium, so the current production process of vanadium-nitrogen alloy mainly comprises a high-temperature vacuum method and a high-temperature non-vacuum method. For example, Chinese patent CN103243254A provides a production method of vanadium-nitrogen alloy, wherein firstly, vanadium pentoxide is reduced into vanadium tetraoxide, then carbon powder is added for carrying out segmented reaction again, but nitrogen is required to be introduced and then a certain positive pressure is maintained, and meanwhile, the temperature is raised to 1500-1600 ℃; the high temperature non-vacuum method of blast furnace adopted at present needs the temperature of nitriding to be 1800 ℃ in the production process, and the energy consumption is high.
In summary, the existing methods for producing vanadium nitride alloys either operate in a vacuum environment or increase the temperature above 1800 ℃ to densify the vanadium nitride. The preparation method of the vanadium nitride alloy has the advantages of complex production process, long production period, higher equipment requirement, higher reaction temperature and high energy consumption.
Disclosure of Invention
In view of the above, the present invention aims to provide a method for preparing a vanadium-nitrogen alloy in a rotary hearth furnace. The method adopts the rotary hearth furnace to prepare the vanadium-nitrogen alloy, the working area of the rotary hearth furnace can fully meet the requirements for preparing the vanadium-nitrogen alloy, and the method has the advantages of simple process, strong operability, short production period and low energy consumption loss.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a method for preparing vanadium-nitrogen alloy by a rotary hearth furnace, which comprises the following steps:
mixing and crushing vanadium oxide and carbonaceous reducing agent, and pressing the mixture into balls under the action of a binder to obtain ball materials;
and (3) putting the ball material into a rotary hearth furnace, introducing nitrogen into the rotary hearth furnace, carrying out high-temperature reaction, and cooling to obtain the vanadium-nitrogen alloy.
Preferably, the high temperature reaction comprises two stages of high temperature carbothermic reduction and nitridation reactions.
Preferably, the high-temperature reaction is carried out at 1200-1600 ℃ for 10-50 min.
Preferably, the mass ratio of the vanadium oxide to the carbonaceous reducing agent is 3-5: 1.
Preferably, the flow rate of the nitrogen is 1500-2500 mL/min.
Preferably, the rotating speed of the rotary hearth furnace is 30-80 min/r.
Preferably, the high-temperature reaction also comprises low-temperature preheating before the high-temperature reaction.
Preferably, the low-temperature preheating temperature is 500-680 ℃, and the time is 5-15 min.
Preferably, the cooling is furnace cooling, the end point temperature of the cooling is 15-35 ℃, and the time is 5-15 min.
Preferably, the pressure for pressing the pellets is 10-20 MPa, and the pressure maintaining time is 3-10 s.
The invention provides a method for preparing vanadium-nitrogen alloy by a rotary hearth furnace, which comprises the following steps: mixing and crushing vanadium oxide and carbonaceous reducing agent, and pressing the mixture into balls under the action of a binder to obtain ball materials; and (3) putting the ball material into a rotary hearth furnace, introducing nitrogen into the rotary hearth furnace, carrying out high-temperature reaction, and cooling to obtain the vanadium-nitrogen alloy. According to the invention, the vanadium-nitrogen alloy is prepared by using the rotary hearth furnace, three working areas (the low-temperature preheating area, the high-temperature reducing area and the cooling area) of the rotary hearth furnace are fully utilized, compared with the vanadium-nitrogen alloy prepared by reducing the traditional blast furnace, the vanadium-nitrogen alloy prepared by using the rotary hearth furnace has less heat loss, and has the advantages of simple process, strong operability and short production period. The data of the embodiment show that the vanadium-nitrogen alloy prepared by the invention has the nitrogen content of 10-20%, the oxygen content of less than 0.5% and the purity of more than 98%.
Detailed Description
The invention provides a method for preparing vanadium-nitrogen alloy by a rotary hearth furnace, which comprises the following steps:
mixing and crushing vanadium oxide and carbonaceous reducing agent, and pressing the mixture into balls under the action of a binder to obtain ball materials;
and (3) putting the ball material into a rotary hearth furnace, introducing nitrogen into the rotary hearth furnace, carrying out high-temperature reaction, and cooling to obtain the vanadium-nitrogen alloy.
The vanadium oxide and the carbonaceous reducing agent are mixed and crushed, and then pressed into balls under the action of the binder, so that the ball material is obtained.
In the present invention, the vanadium oxide is preferably V2O3、V2O5And one or more of ammonium polyvanadate; the carbonaceous reducing agent is preferably one or more of graphite, carbon black, coke, activated carbon and other carbonaceous reducing agents; the binder is preferably one or more of Polyacrylamide (PAM), polyvinyl alcohol (PVA) and epoxy resin binder. The invention has no special limitation on the dosage of the binder, and can ensure that the ball material can be obtained.
In the invention, the mass ratio of the vanadium oxide to the carbonaceous reducing agent is preferably 3-5: 1, and more preferably 10: 3.3.
In the present invention, the crushing is preferably to less than 150 mesh.
In the invention, the pressure for pressing the balls is preferably 10-20 MPa, and the pressure maintaining time is preferably 3-10 s, and more preferably 8 s.
After the ball material is obtained, the ball material is put into a rotary hearth furnace, nitrogen is introduced into the rotary hearth furnace for high-temperature reaction, and the vanadium-nitrogen alloy is obtained after cooling.
In the present invention, the high temperature reaction preferably comprises two stages of high temperature carbothermic reduction and nitridation reactions.
In the invention, the high-temperature reaction temperature is preferably 1200-1600 ℃, more preferably 1450-1550 ℃, and the time is preferably 10-50 min, more preferably 30 min.
In the invention, the flow rate of the nitrogen is preferably 1500-2500 mL/min, and more preferably 1800-2100 mL/min.
In the invention, the rotating speed of the rotary hearth furnace is preferably 30-80 min/r, and more preferably 40-50 min/r. Compared with the traditional blast furnace reduction preparation of vanadium-nitrogen alloy, the rotary hearth furnace preparation of vanadium-nitrogen alloy has the advantages of less heat loss, simple process, strong operability and short production period.
In the present invention, it is preferable to further include low-temperature preheating before the high-temperature reaction.
In the invention, the low-temperature preheating temperature is preferably 500-680 ℃, more preferably 650 ℃, and the time is preferably 5-15 min, more preferably 10 min.
In the invention, the cooling is preferably furnace cooling, the end point temperature of the cooling is preferably 15-35 ℃, more preferably 25 ℃, and the time is preferably 5-15 min, more preferably 10 min.
The vanadium-nitrogen alloy prepared by the method has the nitrogen content of 10-20%, the oxygen content of less than 0.5% and the purity of more than 98%.
The method for preparing vanadium-nitrogen alloy by using a rotary hearth furnace provided by the invention is described in detail with reference to the following examples, but the method is not to be construed as limiting the scope of the invention.
Example 1
With V2O5And coke is used as raw material, and the raw material is V2O510kg of coke, 3.30kg of coke, mixing with V2O5And crushing coke into powder samples with the granularity of less than 150 meshes, uniformly stirring, selecting polyvinyl alcohol (PVA) as a binder, and pressing for 10s under the pressure of 10MPa to form balls.
And (3) putting the pressed pellets into a rotary hearth furnace, setting the rotating speed of the rotary hearth furnace to be 40min/r, setting the temperature of a low-temperature preheating zone of the rotary hearth furnace to be 650 ℃, and keeping the temperature for 5 min. And then entering a high-temperature reduction region for high-temperature carbothermic reduction and nitridation, setting the temperature of the high-temperature reduction region to 1450 ℃, keeping the temperature for 30min, wherein the introduction rate of nitrogen is 1800mL/min, finally entering a cooling region, and cooling to room temperature (25 ℃) along with a furnace for 5min to obtain the vanadium-nitrogen alloy. The nitrogen content in the obtained vanadium-nitrogen alloy is as follows: 15.39%, oxygen content: 0.31 percent and the purity is more than 98 percent.
Example 2
With V2O5And graphite as raw material V2O510kg of coke, 3.30kg of coke, mixing with V2O5Crushing graphite into powder with the granularity of less than 150 meshes, uniformly stirring, and selectingPolyacrylamide (PAM) as a binder was pressed at a pressure of 20MPa for 10s to form balls.
And (3) putting the pressed pellets into a rotary hearth furnace, setting the rotating speed of the rotary hearth furnace to be 50min/r, setting the temperature of a low-temperature preheating zone of the rotary hearth furnace to be 650 ℃, and keeping the temperature for 10 min. And then entering a high-temperature reduction region for high-temperature carbothermic reduction and nitridation, setting the temperature of the high-temperature reduction region to 1550 ℃, keeping the temperature for 30min, wherein the introduction rate of nitrogen is 2100mL/min, finally entering a cooling region, and cooling to room temperature (25 ℃) along with a furnace for 10min to obtain the vanadium-nitrogen alloy. The nitrogen content in the obtained vanadium-nitrogen alloy is as follows: 17.39%, oxygen content: 0.26% and purity more than 98%.
Example 3
With V2O5And active carbon as raw material, adopting raw material V2O510kg of coke, 3.30kg of coke, mixing with V2O5And crushing the active carbon into powder samples with the granularity of less than 150 meshes, uniformly stirring, selecting polyvinyl alcohol (PVA) as a binder, and pressing for 8s under the pressure of 15MPa to form balls.
And (3) putting the pressed pellets into a rotary hearth furnace, setting the rotating speed of the rotary hearth furnace to be 80min/r, setting the temperature of a low-temperature preheating zone of the rotary hearth furnace to be 680 ℃, and keeping the temperature for 15 min. And then entering a high-temperature reduction region for high-temperature carbothermic reduction and nitridation, setting the temperature of the high-temperature reduction region to be 1200 ℃, keeping the temperature for 50min, wherein the introduction rate of nitrogen is 1500mL/min, finally entering a cooling region, and cooling to room temperature (25 ℃) along with a furnace for 15min to obtain the vanadium-nitrogen alloy. The nitrogen content in the obtained vanadium-nitrogen alloy is as follows: 14.39%, oxygen content: 0.35% and purity more than 98%.
Example 4
With V2O3And active carbon as raw material, adopting raw material V2O310kg of coke, 3.30kg of coke, mixing with V2O3And crushing the active carbon into powder samples with the granularity of less than 150 meshes, uniformly stirring, selecting polyvinyl alcohol (PVA) as a binder, and pressing the mixture for 5s under the pressure of 10MPa to form balls.
And (3) putting the pressed pellets into a rotary hearth furnace, setting the rotating speed of the rotary hearth furnace to be 30min/r, setting the temperature of a low-temperature preheating zone of the rotary hearth furnace to be 500 ℃, and keeping the temperature for 10 min. And then entering a high-temperature reduction region for high-temperature carbothermic reduction and nitridation, setting the temperature of the high-temperature reduction region to 1600 ℃, keeping the temperature for 10min, wherein the introduction rate of nitrogen is 2500mL/min, finally entering a cooling region, and cooling to 35 ℃ along with a furnace for 10min to obtain the vanadium-nitrogen alloy. The nitrogen content in the obtained vanadium-nitrogen alloy is as follows: 12.39%, oxygen content: 0.41 percent and the purity is more than 98 percent.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (1)
1. The method for preparing the vanadium-nitrogen alloy by the rotary hearth furnace is characterized by comprising the following steps of:
mixing and crushing vanadium oxide and carbonaceous reducing agent, and pressing the mixture into balls under the action of a binder to obtain ball materials; the vanadium oxide is V2O5The carbonaceous reducing agent is graphite, the mass ratio of the vanadium oxide to the carbonaceous reducing agent is 10:3.3, and the binder is polyacrylamide; the pressure for pressing the pellets into balls is 20MPa, and the pressure maintaining time is 10 s;
putting the ball material into a rotary hearth furnace, introducing nitrogen into the rotary hearth furnace, carrying out high-temperature reaction, and cooling to obtain vanadium-nitrogen alloy; the flow rate of the nitrogen is 2100mL/min, and the rotating speed of the rotary hearth furnace is 50 min/r; the method also comprises low-temperature preheating before the high-temperature reaction, wherein the low-temperature preheating temperature is 650 ℃ and the time is 10 min; the temperature of the high-temperature reaction is 1550 ℃, and the time is 30 min; the cooling is furnace cooling, the end temperature of the cooling is 25 ℃, and the time is 10 min.
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| CN113684363B (en) * | 2021-08-05 | 2022-09-27 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for producing vanadium-nitrogen alloy with preset sulfur content |
| CN116334466A (en) * | 2021-12-15 | 2023-06-27 | 陕西五洲矿业股份有限公司 | Processing technology for preparing vanadium-nitrogen alloy based on powdery vanadium pentoxide |
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| CN106148751A (en) * | 2016-08-01 | 2016-11-23 | 江苏省冶金设计院有限公司 | Prepare the method and system of nitrogen-vanadium alloy |
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| US3591367A (en) * | 1968-07-23 | 1971-07-06 | Reading Alloys | Additive agent for ferrous alloys |
| CN101603132A (en) * | 2009-07-16 | 2009-12-16 | 钢铁研究总院 | A kind of method and apparatus of production VN alloy |
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