CN108080649B - Method for preparing superfine iron powder by low-temperature hydrocarbon duplex reduction - Google Patents
Method for preparing superfine iron powder by low-temperature hydrocarbon duplex reduction Download PDFInfo
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- B22F2009/043—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by ball milling
Abstract
A method for preparing superfine iron powder by low-temperature carbon-hydrogen duplex reduction comprises the following steps of firstly, ball-milling iron concentrate powder with certain purity, carbon powder and a catalyst respectively; step two, uniformly mixing the ball-milled materials in the step one according to a certain proportion; step three, placing the uniformly mixed materials in a protective atmosphere for heating reduction, and cooling to obtain primary reduced iron; step four, ball milling the primary reduced iron obtained in the step three; step five, placing the primary reduced iron subjected to ball milling in the step four in a hydrogen atmosphere for final reduction, and discharging the iron after cooling to obtain reduced iron powder; and step six, performing ball milling on the reduced iron powder in the step five to obtain superfine iron powder. Compared with the prior art, the method has the advantages of low reaction temperature, low energy consumption, low hydrogen consumption and the like, high-quality superfine iron powder is easy to obtain, and the preparation process is simple, the energy consumption is low, and the production cost is low.
Description
Technical Field
The invention relates to the field of powder metallurgy preparation, in particular to a low-temperature carbon-hydrogen duplex reduction preparation method for preparing micron-sized and submicron-sized superfine iron powder.
Background
In the prior art, micron-sized iron powder is one of basic raw materials in the powder metallurgy industry, and the particle size is 1-10 microns. The micron-sized iron powder has larger specific surface area and activity, and is mainly used in the fields of powder metallurgy, manufacturing of mechanical parts, production of friction materials, antifriction materials, superhard materials, magnetic materials, lubricants, products thereof and the like. In recent years, the method has wide application prospects in various fields such as electromagnetism, biology, medicine, optics and the like. Especially, the development of 3D printing technology will promote the market of superfine iron powder to further expand.
Most of the traditional iron powder is produced by a two-step reduction method, namely, in the first step, a tunnel kiln is adopted for reduction to obtain an iron ingot with the reduction rate of 97-98%, the iron ingot is crushed and ball-milled to form 100-200-mesh iron powder, and the oxygen content of the iron powder is reduced to about 0.5% by hydrogen reduction. Because the reduction temperature of the tunnel kiln is high (1150 ℃) and the smelting period is long (72 hours), the product obtained in the first step can only be an iron ingot. Due to the ductility of iron, the iron is difficult to be ground to below 40 microns at low cost, and the price of the iron powder is low. The other superfine iron powder process adopts ball milling common iron powder and multi-stage grading and hydrogen reduction, and has low yield, high power consumption, low yield and low economic performance.
The small amount of iron powder is atomized, and through melting industrial pure iron in a medium frequency induction furnace and preparing 100-200 mesh iron powder in rotating atomizing equipment, superfine iron powder may not be obtained. The atomization method is suitable for making alloy powder.
The following methods can prepare the superfine iron powder:
1) carbonyl process
The preparation of carbonyl iron powders is generally carried out by the conventional thermal decomposition process, i.e. by reacting Fe (CO)5Directly decomposing at a certain temperature to prepare iron powder. The principle of the laser pyrolysis method is to utilize a continuous laser flow system to react carbonyl compounds Fe (CO)5Cracking to prepare the superfine iron powder. But because of the higher cost of the carbonyl process system and the Fe (CO)5The method is a toxic and explosive substance, the operation of the whole process flow is complex, the processing cost is high, and the mass production can be realized at present to form large-scale production.
2) Gas phase reduction process
The gas phase reduction method is generally to add FeCl2Evaporating the iron salt at high temperature, using H in the gas phase2Or NH3Used as a reducing agent to prepare the superfine iron powder. The reaction process comprises three steps of ferric salt dehydration, evaporation and gas phase reduction. The A-Fe is instantaneously nucleated in the gas phase reduction method, the nucleation temperature is lower, and the grain diameter of the iron powder is small and granularThe degree distribution is centralized; however, the reaction is carried out in a gas phase, so that the reaction process is fine, the reaction is easily influenced by devices and the like, the stability is not good, and the mass production is not available at present.
3) Solid phase reduction process
The solid phase reduction process is generally referred to as in H2Under the atmosphere, FeC is added2O4·2H2And decomposing and reducing precursors such as O or FeOOH and the like to prepare the superfine iron powder. The reduction temperature is suitably 510 ℃. The method has extremely high requirements on the preparation of the precursor, and the large-scale preparation is difficult at present.
4) Vacuum evaporation method and sputtering method
The vacuum evaporation method refers to a method of evaporating a metal in vacuum and then cooling and condensing its vapor to obtain a metal micropowder. The sputtering method is to prepare high-melting point superfine metal powder by using sputtering phenomenon instead of evaporation, and can be used for preparing metal iron powder. The method has the advantages that the prepared ultrafine powder has concentrated particle size distribution and uniform particles, and has the defect that the vacuum environment is difficult to realize during industrial production.
5) High energy ball milling process
The high energy ball milling method is a method in which hard balls are strongly collided, ground and stirred with metallic iron by using the rotation or vibration of a ball mill to pulverize the powder into ultrafine particles. Because the metal iron has metal ductility, the preparation of micron-level and submicron-level iron powder is difficult and has high energy consumption.
6) Simultaneous hydrogen reduction of iron oxide high-energy ball mill
And (3) putting the pure iron oxide raw material into a ball mill for ball milling and refining, and introducing hydrogen gas at 200-350 ℃ for reduction to obtain the superfine iron powder. This method can produce ultrafine iron powder, but the hydrogen gas conversion rate at low temperature is low, resulting in a high hydrogen gas consumption.
Disclosure of Invention
In view of the above analysis, the present invention provides a method for preparing superfine iron powder, which has the advantages of low energy consumption, easy obtaining of high quality superfine iron powder, simple preparation process and low production cost.
The purpose of the invention is mainly realized by the following technical scheme:
a method for preparing superfine iron powder by low-temperature hydrocarbon duplex reduction comprises the following steps:
step one, performing ball milling on iron concentrate powder with certain purity, carbon powder and a catalyst respectively;
step two, uniformly mixing the ball-milled materials in the step one according to a certain proportion;
step three, placing the uniformly mixed materials in a protective atmosphere for heating reduction, and cooling to obtain primary reduced iron;
step four, ball milling the primary reduced iron obtained in the step three;
step five, placing the primary reduced iron subjected to ball milling in the step four in a hydrogen atmosphere for final reduction, and discharging the iron after cooling to obtain reduced iron powder;
and step six, performing ball milling on the reduced iron powder in the step five to obtain superfine iron powder.
Further, the first step is specifically that the iron ore concentrate powder is ground to d50Is 6 μm and d90<10 microns; grinding carbon powder to d50<10 μm and d90<20 microns; the catalyst was ground to below 325 mesh.
Further, the iron ore concentrate powder contains over 71.0 percent of total iron and less than 0.2 percent of acid insoluble matters; the ash content of the carbon powder is less than 3 percent, and the sum of volatile matter and water is less than 8 percent.
Because the content of impurities in the reducing agent carbon powder is not too high to prepare pure iron powder, otherwise the grade of the metal iron powder is influenced. Research shows that ash content in the carbon powder is less than 3%, and the sum of water content and volatile matter content in the carbon powder is less than 8%, because the content is too high, the total amount of the added carbon powder is increased, and the content of impurities exceeds the standard.
Further, the catalyst is potassium carbonate, sodium carbonate or a mixture of the two.
Further, in the second step, the mass ratio of the iron ore concentrate powder to the carbon powder to the catalyst is 100: 15-20: 0.5-1.5.
A small amount of alkaline carbonate catalyst is added, so that the low-temperature reaction performance of the iron oxide can be accelerated, but the iron powder grade is reduced by excessive addition, researches show that the catalyst is a high-efficiency additive selected from potassium carbonate, sodium carbonate or a mixture of the potassium carbonate and the sodium carbonate, and the addition amount is preferably 0.5-1.5% of the mass of the iron concentrate powder.
The carbon powder is mainly used for reducing the consumption of hydrogen for reducing hydrogen. The carbon addition amount is too small, so that the significance of reducing the hydrogen amount in the technical process is small, a working procedure is added, and the cost is increased; the carbon addition is too high, so that the carbon content in the iron powder is easy to exceed the standard, and researches show that the addition of the carbon is 15-20% of the mass of the fine iron powder.
Further, the heating reduction temperature in the third step is 800-850 ℃, the heating time is 2-3 hours, the paving thickness of the material is 10-30 mm, and the protective atmosphere is nitrogen or argon.
From kinetics, the finer the granularity is, the faster the reaction speed is or the lower the required reaction temperature is, so that the carbon thermal reduction temperature of the superfine iron concentrate powder is only 800-850 ℃, and the reaction iron grains are not easy to grow at the temperature. The reaction temperature is too high, the iron powder is easy to sinter into hard blocks, and superfine iron powder cannot be obtained. The reduction time is preferably 2-3 h, and when the material thickness is thinner, the reduction time is shorter, and vice versa. And the iron powder is easy to sinter due to the overlong reduction time.
The material thickness of the reduction furnace is not suitable to be too thick, because the mixed bulk density of the superfine iron concentrate powder, the carbon powder and the like is small, the heat transfer is poor, and the too thick heat is not suitable to be transferred to the material center. Researches show that 10-30 mm materials are suitable.
Further, the fourth step is to ball mill the primary reduced iron of the third step to 325 meshes.
The carbon-reduced iron powder is ground, which is equivalent to mixing the materials once, so that the subsequent hydrogen reduction product has more uniform quality.
Further, in the fifth step, the reduction temperature is 750-800 ℃, the material thickness in the reduction process is 10-30 mm, and the reduction time is 1-3 h.
The fine granularity of the primary iron powder in hydrogen reduction is not suitable for the reduction temperature to be too high, the iron powder is easy to sinter, and the too low reaction is not thorough.
Further, in the sixth step, the superfine iron powder is d50<7 μm, d90<12 micron superfine iron powder.
The iron powder after hydrogen reduction forms soft blocks, and the bulk density is about 0.5-0.7 g/cm3And the raw materials are ground to meet the specified product requirements.
Further, the atmosphere heating furnace used in the reduction process is a steel strip atmosphere heating furnace or a boat pushing atmosphere heating furnace; the heating process adopts electric heating or gas heating.
The invention has the following beneficial effects:
aiming at the defects in the prior art, the invention provides a low-temperature carbon-hydrogen duplex reduction preparation method for preparing micron-grade and submicron-grade superfine iron powder, and d is obtained by controlling the process parameters of each step50<7 μm and d90<12 micron superfine iron powder.
The invention overcomes the defects in the prior art, such as high reduction temperature of high-temperature gas-based and coal-based reduction methods and large particle size of iron powder; the high-energy ball milling method is very difficult because the specific ductility of iron powder is very difficult to be ground to the micron or submicron level, and the power consumption is very high. Compared with the prior art, the method has the advantages of low reaction temperature, low energy consumption, low hydrogen consumption and the like, high-quality superfine iron powder is easy to obtain, and the preparation process is simple, the energy consumption is low, and the production cost is low.
Compared with the prior tunnel kiln process, the reduction temperature of the tunnel kiln is reduced to 800-850 ℃ and the heating time is reduced to 2-3 h from 48h, more importantly, the smelting conditions can ensure that the granularity of the primary reduced iron powder is fine, and the sintering is serious during the reduction of the tunnel kiln, so that the primary reduced iron powder becomes an iron ingot. By the low-temperature duplex preparation process of the superfine iron powder, about 80 percent of hydrogen consumption can be reduced, and the preparation cost of the superfine iron powder is greatly reduced.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
Drawings
The drawings are only for purposes of illustrating particular embodiments and are not to be construed as limiting the invention, wherein like reference numerals are used to designate like parts throughout.
FIG. 1 is a process flow chart of the preparation of ultrafine iron powder by the low-temperature hydrocarbon duplex reduction method of the invention.
Fig. 2 is a particle size distribution diagram of the ultra-fine iron powder product obtained by the present invention.
Detailed Description
The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form a part hereof, and which together with the embodiments of the invention serve to explain the principles of the invention.
Aiming at the defects in the prior preparation technology, such as high reduction temperature of high-temperature gas-based and coal-based reduction methods and large particle size of iron powder; the high-energy ball milling method is quite difficult to grind the specific ductility of the iron powder to micron or submicron grade, and the power consumption is extremely high, so that in order to prepare high-purity superfine iron powder, the invention develops a method for preparing superfine iron powder by low-temperature hydrocarbon duplex reduction, which comprises the following steps:
firstly, ball milling, namely milling pure iron concentrate powder (acid insoluble matter is less than 0.2%) with total iron of more than 71.0% by a ball mill until d50About 6 microns, d90<10 microns, grinding pure carbon powder (ash content is less than 3%, volatile component and water content are less than 8%) to d50<10 μm, d90<20 microns, and the catalyst is potassium carbonate (analytically pure), sodium carbonate (analytically pure) or a combination of the potassium carbonate and the sodium carbonate, which are ground to below 325 meshes.
A small amount of alkaline carbonate catalyst is added, so that the low-temperature reaction performance of the iron oxide can be accelerated, but the iron powder grade is reduced by excessive addition, researches show that the catalyst is a high-efficiency additive selected from potassium carbonate, sodium carbonate or a mixture of the potassium carbonate and the sodium carbonate, and the addition amount is preferably 0.5-1.5% of the mass of the iron concentrate powder.
Secondly, proportioning and uniformly mixing, namely proportioning the finely ground iron concentrate powder, carbon powder and a catalyst according to the mass ratio of 100: 15-20: 0.5-1.5, and then uniformly mixing.
And thirdly, carbon reduction, namely, putting the uniformly mixed material into an atmosphere protection heating furnace for heating reduction, wherein the protection atmosphere is nitrogen or argon, the temperature is 800-850 ℃, the heating time is 2-3 h, the paving thickness is 10-30 mm, and the primary reduced iron is obtained after reduction and cooling.
The preparation method of the superfine iron powder provided by the invention combines the advantages of a gas-based reduction method, a carbothermic reduction method and a ball milling method, iron oxide belongs to brittle substances, and iron powder belongs to plastic substances, so that the iron oxide can be more easily crushed to a micron level. From kinetics, the finer the granularity is, the faster the reaction speed is or the lower the required reaction temperature is, so that the carbon thermal reduction temperature of the superfine iron concentrate powder is only 800-850 ℃, and the reaction iron grains are not easy to grow at the temperature. The reaction temperature is too high, the iron powder is easy to sinter into hard blocks, and superfine iron powder cannot be obtained. The reduction time is preferably 2-3 h, and when the material thickness is thinner, the reduction time is shorter, and vice versa. And the iron powder is easy to sinter due to the overlong reduction time.
Because the content of impurities in the reducing agent carbon powder is not too high to prepare pure iron powder, otherwise the grade of the metal iron powder is influenced. Research shows that ash content in the carbon powder is less than 3%, and the sum of water content and volatile matter content in the carbon powder is less than 8%, because the content is too high, the total amount of the added carbon powder is increased, and the content of impurities exceeds the standard. The carbon powder is mainly used for reducing the consumption of hydrogen for reducing hydrogen. The carbon addition amount is too small, so that the significance of reducing the hydrogen amount in the technical process is small, a working procedure is added, and the cost is increased; the carbon addition is too high, so that the carbon content in the iron powder is easy to exceed the standard, and researches show that the addition of the carbon is 15-20% of the mass of the fine iron powder.
The material thickness of the reduction furnace is not suitable to be too thick, because the mixed bulk density of the superfine iron concentrate powder, the carbon powder and the like is small, the heat transfer is poor, and the too thick heat is not suitable to be transferred to the material center. Researches show that 10-30 mm materials are suitable.
And step four, carrying out primary reduced iron ball milling, and grinding primary reduced iron powder to 325 meshes in a ball mill.
The carbon-reduced iron powder is ground, which is equivalent to mixing the materials once, so that the subsequent hydrogen reduction product has more uniform quality.
And fifthly, hydrogen reduction, namely placing the ground primary reduced iron powder into an atmosphere protection heating furnace for final reduction by using hydrogen, wherein the reduction temperature is 750-800 ℃, the material thickness is 10-30 mm, the reduction time is 1-3 h, and the reduced iron powder is cooled in a cooling section of the heating furnace and then discharged.
The fine granularity of the primary iron powder in hydrogen reduction is not suitable for the reduction temperature to be too high, the iron powder is easy to sinter, and the too low reaction is not thorough. Research shows that the suitable hydrogen reduction conditions of the primary reduced iron powder are as follows: the thickness of the primary reduced iron powder is 10-30 mm, the heating time is 1-3 h, and the heating temperature is 750-800 ℃.
Sixthly, carrying out hydrogen reduced iron powder ball milling, and levigating the hydrogen reduced iron powder to d through a ball mill50<7 μm, d90<12 micron superfine iron powder.
The iron powder after hydrogen reduction forms soft blocks, and the bulk density is about 0.5-0.7 g/cm3And the raw materials are ground to meet the specified product requirements.
In the invention, the carbon reduction heating furnace and the hydrogen reduction heating furnace can adopt a steel strip atmosphere heating furnace or a push boat atmosphere heating furnace, and both can realize the functions of atmosphere protection and hydrogen introduction reduction. The heating can be electric heating or gas heating.
The invention can utilize the existing milling equipment to mill various raw materials and products to specified granularity, such as high-pressure roller and airflow classification, airflow mill and airflow classification, impact mill and airflow classification, stirring mill and the like, but not limited to the equipment.
Compared with the tunnel kiln process, the reduction temperature of the tunnel kiln is reduced to 1150-850 ℃, the heating time is reduced to 2-3 h from 48h, and more importantly, the smelting conditions can ensure that the granularity of the primary reduced iron powder is fine, and the sintering is serious during the reduction of the tunnel kiln, so that the primary reduced iron powder becomes an iron ingot. By the low-temperature duplex preparation process of the superfine iron powder, about 80 percent of hydrogen consumption can be reduced, and the preparation cost of the superfine iron powder is greatly reduced.
Description of the embodiments
Examples 1-3 all prepared ultrafine iron powder by low-temperature hydrocarbon duplex reduction according to the present invention, in the examples, the iron concentrate powder components are shown in table 1, the carbon powder components are shown in table 2, and sodium carbonate and potassium carbonate were analytically pure raw materials.
TABLE 1 pure iron concentrate powder composition/wt%
| TFe | Water content | Acid insoluble substance |
| 71.3 | <1.0 | 0.1 |
TABLE 2 carbon powder composition/wt%
| Volatile matter | Ash content | Fixed carbon | Water content |
| 4.25 | 1.44 | 91.91 | 2.40 |
Grinding pure iron oxide to d50About 6 microns, d90<10 micron, pure carbon powder ground to d50<10 micron, d90<20 microns, the catalyst is ground to below 325 mesh.
In the embodiment, the iron ore concentrate powder is ground in a mode of combining a high-pressure roller mill and an airflow classifier; carrying out superfine grinding on the carbon powder by adopting a mode of combining impact grinding and airflow grading; grinding the catalyst and the primary reduced iron by using a common ball mill; and finely grinding the iron powder after hydrogen reduction by adopting a mode of combining an impact mill and an airflow classifier.
Examples 1-3 tests were carried out according to the formulation in table 3, the furnace in the examples being a steel strip furnace, the reduction was carried out according to the carbon reduction conditions in table 3, the reduction was carried out under nitrogen protection, and the product was ground to 325 mesh level by a ball mill after cooling. Then hydrogen reduction is carried out according to the hydrogen reduction conditions in the table 3, and the product is ball-milled to d after being cooled50<7 μm, d90<12 micron superfine iron powder.
TABLE 3 implementation conditions and results
Example 1
Iron ore concentrate powder, carbon powder and catalyst K2CO3The mass ratio of the ingredients is 100:16.5: 0.6; the temperature for carbon reduction is 820 ℃, the heating time is 1.5h, and the paving thickness is 20 mm; the temperature for hydrogen reduction is 790 ℃, the heating time is 2.0h, and the paving thickness is 20 mm; the final superfine iron powder product contains total iron 98.5%, C0.02%, residual oxygen 0.25% and acid insoluble 0.1%.
Example 2
Iron ore concentrate powder, carbon powder and catalyst Na2CO3The mass ratio of the ingredients is 100:18.2: 1.2; the carbon reduction is carried out at 840 ℃ for a heating time of2.5h, paving the material with the thickness of 25 mm; the temperature for hydrogen reduction is 760 ℃, the heating time is 2.5h, and the paving thickness is 25 mm; the final superfine iron powder product contains total iron 98.3%, C0.03%, residual oxygen 0.26% and acid insoluble 0.09%.
Example 3
The weight ratio of the iron concentrate powder to the carbon powder to the catalyst is 100:16.5:1.3, and the catalyst is K2CO3And Na2CO3In which K is2CO30.5% of Na2CO30.8 percent; the temperature for carbon reduction is 820 ℃, the heating time is 1.5h, and the paving thickness is 20 mm; the temperature for hydrogen reduction is 790 ℃, the heating time is 2.0h, and the paving thickness is 20 mm; the final superfine iron powder product contains total iron 98.5%, C0.02%, residual oxygen 0.25% and acid insoluble 0.1%.
The chemical components of the products obtained in examples 1-3 meet the requirements of national powder metallurgy industry, wherein the residual carbon, acid insoluble substances, residual oxygen and the like are lower than those of other similar superfine iron powder, the particle size distribution of the final product is shown in figure 2, d50Is 5.76 μm, d9010.98 microns and 21.21 microns, and the loose packed density of the product is 1.2-1.5 g/cm3。
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.
Claims (4)
1. A method for preparing superfine iron powder by low-temperature hydrocarbon duplex reduction is characterized in that the method combines a gas-based reduction method, carbothermic reduction and a ball milling method, and the method comprises the following steps:
step one, performing ball milling on iron concentrate powder with certain purity, carbon powder and a catalyst respectively;
step two, uniformly mixing the ball-milled materials in the step one according to a certain proportion;
step three, placing the uniformly mixed materials in a protective atmosphere for heating reduction, and cooling to obtain primary reduced iron;
step four, ball milling the primary reduced iron obtained in the step three;
step five, placing the primary reduced iron subjected to ball milling in the step four in a hydrogen atmosphere for final reduction, and discharging the iron after cooling to obtain reduced iron powder;
step six, performing ball milling on the reduced iron powder in the step five to obtain superfine iron powder;
the first step is to finely grind the iron ore concentrate powder to d50Is 6 μm and d90<10 microns; grinding carbon powder to d50<10 μm and d90<20 microns; grinding the catalyst to below 325 meshes;
the acid insoluble matters in the iron ore concentrate powder are less than 0.2 percent; the sum of the volatile matter and the water content of the carbon powder is less than 8 percent;
the iron ore concentrate powder contains more than 71.0 percent of total iron; the ash content of the carbon powder is less than 3 percent;
in the second step, the mass ratio of the iron concentrate powder to the carbon powder to the catalyst is 100: 15-20: 0.5-1.5;
the temperature of heating reduction in the third step is 800-850 ℃, the heating time is 2-2.5 hours, and the paving thickness of the material is 10-30 mm;
the fourth step is specifically that the primary reduced iron in the third step is ball-milled to 325 meshes;
in the fifth step, the reduction temperature is 750-800 ℃, the thickness of the material in the reduction process is 10-30 mm, and the reduction time is 1-2.5 h;
in the sixth step, the superfine iron powder is d50<7 μm, d90<12 micron superfine iron powder.
2. The method for preparing the superfine iron powder by the low-temperature hydrocarbon double reduction according to claim 1, wherein the catalyst is potassium carbonate, sodium carbonate or a mixture of the potassium carbonate and the sodium carbonate.
3. The method for preparing superfine iron powder by low-temperature hydrocarbon duplex reduction according to claim 1, wherein the temperature of heating reduction in the third step is 820-840 ℃, the heating time is 2-2.5 h, the paving thickness of the material is 15-25 mm, and the protective atmosphere is nitrogen or argon.
4. The method for preparing superfine iron powder by low-temperature hydrocarbon duplex reduction according to any one of claims 1 to 3, wherein the atmosphere heating furnace used in the reduction process is a steel strip atmosphere heating furnace or a pusher-boat atmosphere heating furnace; the heating process adopts electric heating or gas heating.
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| WO2023067498A1 (en) * | 2021-10-19 | 2023-04-27 | Pometon Spa | Plant and use of a plant for obtaining metal powders for burners |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR970002097B1 (en) * | 1994-12-20 | 1997-02-22 | 김만제 | Method of iron powder |
| CN1641053A (en) * | 2005-01-07 | 2005-07-20 | 梅卫东 | Composite additive for vanadium-titanium magnetite reduction |
| CN101586172A (en) * | 2009-07-06 | 2009-11-25 | 何德武 | Method for preparing metallized pellet and reduced iron powder |
| CN104190950A (en) * | 2014-07-25 | 2014-12-10 | 玉溪大红山矿业有限公司 | Iron powder production process |
| CN106238745A (en) * | 2016-08-19 | 2016-12-21 | 朝阳金河粉末冶金材料有限公司 | The method utilizing strip stove temperature production reduced iron powder |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8333821B2 (en) * | 2010-02-05 | 2012-12-18 | Innova Powders, Inc. | Environmentally friendly system and method for manufacturing iron powder |
-
2017
- 2017-12-14 CN CN201711340876.0A patent/CN108080649B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR970002097B1 (en) * | 1994-12-20 | 1997-02-22 | 김만제 | Method of iron powder |
| CN1641053A (en) * | 2005-01-07 | 2005-07-20 | 梅卫东 | Composite additive for vanadium-titanium magnetite reduction |
| CN101586172A (en) * | 2009-07-06 | 2009-11-25 | 何德武 | Method for preparing metallized pellet and reduced iron powder |
| CN104190950A (en) * | 2014-07-25 | 2014-12-10 | 玉溪大红山矿业有限公司 | Iron powder production process |
| CN106238745A (en) * | 2016-08-19 | 2016-12-21 | 朝阳金河粉末冶金材料有限公司 | The method utilizing strip stove temperature production reduced iron powder |
Non-Patent Citations (2)
| Title |
|---|
| 低温下碳还原氧化铁的催化机理研究;郭培民等;《钢铁钒钛》;20061231;第27卷(第4期);1-5 * |
| 利用粉体纳米晶化促进低温冶金反应的研究;赵沛等;《钢铁》;20050630;第40卷(第6期);6-9 * |
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