CN1177013A - Method and apparatus for smelting high melting metal by plasma - Google Patents

Method and apparatus for smelting high melting metal by plasma Download PDF

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Publication number
CN1177013A
CN1177013A CN 96119824 CN96119824A CN1177013A CN 1177013 A CN1177013 A CN 1177013A CN 96119824 CN96119824 CN 96119824 CN 96119824 A CN96119824 A CN 96119824A CN 1177013 A CN1177013 A CN 1177013A
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furnace
smelting
plasma
high melting
furnace charge
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CN1051579C (en
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曹永仙
徐永香
高连让
赵素琴
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Institute of Mechanics of CAS
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Abstract

In the invented method we adopt making furnace charge briquet ,drying and plasma furnace smelting three steps to smelt high melting metal. The smelting equipment is a plasma furnace, in which three graphite electrodes are fitted with a space of 120 deg. between each other. The furnace is filled with working medium which can produce plasma. Electric arc is used to heat the furnace charge briquet to proceed smelting reduction so that high melting metal alloy is produced. This method is high in ore utilization rate, low in prodn. cost and high in efficiency.

Description

The method and apparatus of smelting high melting metal by plasma
The present invention relates to the plasma smelting technology, particularly ac plasma single stage method smelting high melting metal ore deposit obtains the method and the device of refractory metal alloy.
At present, extracting the metallurgical method of producing the refractory metal iron alloy at home and abroad mainly contains: electro-silicothermic process, electro-carbothermic process, perrin process (comprising silicothermic process and metal fever method).Perrin process is to utilize silicon, aluminium, ferrosilicon and silumin etc. to react with mineral aggregate, utilizes the reaction heat that produces, and keeps smelting process and is accomplished.The use of this method has limitation, and heat-generating agent cost height, and is very tight to the impurity requirement of mineral aggregate.Electro-silicothermic process and electro-carbothermic process all are under electric furnace heat supply condition, with silicon (or ferrosilicon), carbon mineral aggregate are reduced.Electric furnace is to utilize resistance or air arc to heat, and the temperature height is limited to 2000 ℃, and electrothermal efficiency has only 30-40%, this type of heating is subjected to the restriction of the shape and the resistance of mineral aggregate, require slag that higher resistivity is arranged, make reductive agent with ferrosilicon, its power consumption is big, production cost is high; Make reductive agent with carbon, its fixed carbon and ash content are all had requirement (fixed carbon is not less than 80%, and ash content is not more than 15%), the utilization of coke is restricted.The specific conductivity of counter electrode also has higher requirements, and the cost of electrode is raise, and in use, consumed electrode is very big.And requiring mineral aggregate is lump ore or oxidesintering ore deposit, and powder will lack as far as possible, must carry out pre-treatment to mineral aggregate, guarantees certain temperature, complex procedures.Because of electric furnace is an open type, not only noise is big, and flue dust directly discharges, and causes Working environment seriously polluted, and calorific loss is also very big.And reinforced for batch of material enters, can not continuous dosing, cause power source loads inhomogeneous, the iron alloy of smelting must utilize the method for toppling over to discharge in the stove back that quit work.The problem of its existence is that technical process is long, and the yield of complicated operation, valuable metal is low, power consumption big, deficiency in economic performance.
The object of the present invention is to provide a kind of method and apparatus that adopts hydrogen plasma technology single stage method refining refractory metal.
At the problem that prior art exists, the present invention utilizes ac plasma to have the characteristics (hydrogen ion body arc core temperature is the 6000-7000 degree) that temperature height, concentration of energy, temperature can dig, smelting high melting metal.
The scheme of plasma furnace smelting high melting metal alloy of the present invention is, adopts system furnace charge ball, drying, and plasma furnace is smelted three steps.System furnace charge ball process is coke powder, refractory metal mineral aggregate, auxiliary ingredients to be mixed make the furnace charge ball through adhesive bond; Dry: as to make the finish mix ball dry forming that dries, need not to fuse; Plasma furnace is smelted: add the working medium that can produce plasma body in plasma furnace, the furnace charge ball is dropped into, and make it pass the plasma arc district, be heated and fall into burner hearth, plasma body that carbon and working medium produce and mineral aggregate carry out the smelting reducing reaction and generate refractory metal alloy, be discharged into outside the stove by the refractory metal discharging device, the plasma smelting device is a plasma body stove, is made up of producer and reactor.Producer is a circular platform type, producer is provided with the working medium import that can produce plasma body, cast feeder, three angle-inserting type Graphite Electrodes, the Graphite Electrodess of 120 degree become 0-60 ° of angle with the body of heater plane each other on the body of heater circumference, inwall studs with the furnace lining of high temperature material, its effect is to produce hydrogen plasma, and thermal source is provided.Be provided with the high temperature material burner hearth that has ring groove in the reactor, outer wall is provided with smoke-uptake and refractory metal discharging device, with furnace wall inside and outside the water cooling, the purposes of the ring groove of producer and set of reactors or burner hearth is plasma high-temperature gas metal bath surface in furnace bottom or burner hearth, return otch above the burner hearth again, enter ring groove, improve utilization ratio, the increase reaction probability of heat, ring groove is collected the valuable metal flue dust, is improved its rate of recovery.The reactor effect is to carry out the smelting reducing reaction, generates metal alloy.
Fig. 1 is a hydrogen plasma smelting technology schematic flow sheet of the present invention.
Fig. 2 is a plasma smelting apparatus structure synoptic diagram of the present invention.
Introduce detailed content of the present invention and embodiment below in conjunction with accompanying drawing 1, Fig. 2:
Fig. 1 has provided the process flow diagram of plasma furnace smelting high melting metal alloy method of the present invention, is the single stage method smelting high melting metal.The first step is to make the furnace charge ball after earlier coke powder, refractory metal mineral aggregate, auxiliary ingredients and binding agent being mixed, and auxiliary ingredients is generally lime and fluorite.The refractory metal mineral aggregate generally is tungsten concentrate, concentrated molybdenum ore, tantalum-niobium concentrate, the slag that contains the tantalum niobium and silver preparation concentrate etc., also other refractory metal collective concentrate.Second step was the furnace charge ball dry forming that will make, can adopt several different methods to make its drying, and the exsiccant result can not be scattered the furnace charge ball in fragmentation when entering plasma furnace, and because of water consumption power, corrosion furnace wall.The 3rd step was that plasma furnace is smelted, the interior adding of plasma furnace before this can produce the working medium of plasma body, as hydrogen, nitrogen, coal gas or argon gas etc., the furnace charge ball is dropped into, make the furnace charge ball pass the plasma arc district and be heated and fall into burner hearth, the plasma body that carbon and working medium produce carries out smelting reducing reaction generation insoluble metal alloy with mineral aggregate.
When smelting ferrotungsten, the content percentage and the used share of the used composition of furnace charge ball are: WO3 is 100 parts of 46.54-66.48% and tungsten concentrates, coke powder 18-25 part of fixed carbon 〉=78%, lime 4-10 part of CaO 〉=75%, CaF 2Be fluorite 1.5-4 part of 94%, Na 2SiO 3Binding agent 5-10 part for 40-50%.Obtaining ferrotungsten is: W78-81%, and direct yield 95-98%, foreign matter content meets the requirements.When smelting the tungsten iron alloy, furnace charge ball component content percentage and used share are: WO 3Be 100 parts of the tungsten concentrates of 46.54-66.48%, M 0Be concentrated molybdenum ore 10-21.8 part of 45%, lime 7.5-15.9 part of CaO 〉=75%, coke powder 13-20 part of fixed carbon 〉=78%, Na 2SiO 3Binding agent 5-20 part for 40-50%; Obtaining the molybdenum ferro-tungsten is: (Mo+W) grade 78-82%, and Mo direct yield 92-95%, W direct yield 95-97%, foreign matter content meets the requirements.When smelting tantalum-niobium alloy, furnace charge ball composition percentage and used share are: Ta 2O 5Tantalum-niobium concentrate or Nb for 1.5-3.00% 2O 5Be 100 parts in the slag of 2-4%, coke powder 10-20 part of fixed carbon 〉=78%, lime 9-12 part of CaO 〉=75%, CaF 2Be fluorite 5-10 part of 94%, Na 2SiO 3Binding agent 5-10 part for 40-50% obtains tantalum-niobium alloy, and tantalum niobium concentration ratio is 6-9 tantalum and niobium direct yield 92-95%, satisfies the requirement of producing tantalite niobite power.When smelting ferrocolumbium, furnace charge ball composition percentage and used share are: Nb 2O 5100 parts in the niobium concentrate of 5-20%, coke powder 16-22 part of fixed carbon 〉=78%, lime 3.8-16 part of CaO 〉=75%, Na 2SiO 3Binding agent 5-10 part for 40-50%.Obtain ferrocolumbium, the niobium grade is 11-32%, and niobium direct yield 87-94% satisfies steel-making requirements.
The structure of smelting high melting metal device of the present invention as shown in Figure 2, it is a plasma body stove, it comprises producer 1 and reactor 2 two portions, producer 1 is a circular platform type, be provided with the working medium import 3 that can produce plasma body thereon, throw in the cast feeder 5 of furnace charge ball and the three angle-inserting type Graphite Electrodes 4 of hexagonal angle each other on the body of heater circumference, the producer inwall studs with high temperature resistant furnace lining, its effect is to produce plasma body, and thermal source is provided, cylinder shape in the reactor, its inwall is the high temperature resistant furnace lining that has ring groove 8, burner hearth can adopt conventional cylinder shape, preferably adopts the approximate circle ball-type, and outer wall is provided with smoke-uptake 6 and refractory metal discharging device 7.Be provided with in the outlet of discharging device 7 one with outlet shape identical plug, extract plug after, refractory metal alloy is promptly emitted by discharging device 7.Three root graphite electrodes 4 can become 0-60 ° of angle with the body of heater level as required.Furnace lining in the plasma furnace adopts graphite material or other resistant to elevated temperatures material, is provided with watercooling jacket 9 on outer wall, and inside and outside wall all can adopt water cooling.
Now introduce embodiments of the invention in conjunction with Fig. 1, Fig. 2.Smelting process of the present invention as shown in Figure 1, the prepared furnace charge ball behind the dry forming, can drop into plasma furnace before this.Subordinate list has provided several examples of smelting into the refractory metal iron alloy with different refractory metal mineral aggregates, wherein used coke powder fixed carbon 〉=78%, and working medium adopts the hydrogen of hydrogen richness 99.9%, and auxiliary ingredients is: lime CaO 〉=75%, fluorite CaF 294%, binding agent is: Na 2SiO 340-50%.Plasma furnace as shown in Figure 2, burner hearth adopts the approximate circle ball-type, the furnace wall is provided with watercooling jacket 9, three root graphite electrodes 4 and body of heater horizontal plane angles at 45, adds the voltage of alternating current of 130-150 volt on the Graphite Electrodes 4 of plasma furnace, produces electric arc; Hydrogen relative value 0.4 normal atmosphere that reduces pressure, flow 0.05-0.2 liter/hour, enter into arc region through working medium import 3, produce hydrogen plasma, carry heat and enter reactor 2 again, continue heating for the furnace charge ball.Furnace charge ball warp cast feeder 5 drops in the stove continuously, passes plasma arc and is heated, falls in the burner hearth, and carbon and hydrogen plasma and mineral aggregate carry out the smelting reducing reaction, and the refractory metal iron Yu gold of generation is discharged into outside the stove by refractory metal discharging device 7.The flue gas that produces in the smelting enters ring groove 8 by the burner hearth inner opening, and discharges through smoke-uptake 6, discharges after also can installing dust arrester installation additional and gathering dust again, and reduces and pollutes.
Adopt method of the present invention and device, in the smelting of mineral aggregate, the shape of metal content, granularity and the existence of needs is not all required, considering its economy, thereby the utilization ratio of mineral aggregate is improved; Simultaneously, focusing carbon dust granularity, fixed carbon, ash content and electrode composition are not strict with, and have reduced production cost; Also need not to consider to generate the electric conductivity of slag, only consider its good fluidity, for smelting provides better condition; And do not need to topple over the blowing that gets off, can be under the situation that do not quit work blowing, improved production efficiency.
Subordinate list
Example Example 1 Example 2 Example 3 Example 4 Example 5
Title Tungsten concentrate is smelted into ferrotungsten High tin tungsten ore is smelted into ferrotungsten Non-standard tungsten ore, molybdenum ore are smelted into the molybdenum ferro-tungsten Contain tantalum, slag that niobium is low is smelted into tantalum-niobium alloy The niobium concentrate that detrimental impurity is high becomes ferro-niobium
The ore deposit ?WO 3 66.48 ??WO 3 46.54 WO 3 57.45 ???Ta 2O 5 2.756 ????Nb 2O 5 6.06
Material ?Sn 1.39 ??Sn 9.30 Mo 45.70 ???Nb 2O 5 3.504 ????P 1.03
Main ?Cu 1.60 ??Cu 0.56 Sn 6.102 ???Ca 15.70 ????S 0.12
Want ?S 0.24 ??As 0.16 Cu 2.92 ???SiO 2 28.30 ????F 0.35
Composition % ??TFe 21.95 TFe (two ore deposit sums) 26.00 ???TFe 8.59 ????TFe 36.75
Tungsten concentrate 100 Tungsten concentrate 100 Tungsten ore 100 Slag 100 Mineral aggregate 1.00
Furnace charge Coke powder 18 Coke powder 23 Molybdenum ore 21.80 Coke powder 12 Coke powder 16
Proportioning Lime 4 Lime 8 Coke powder 15 Lime 9-10 Lime 3.8
(％) Fluorite 1.5 Fluorite 2 Lime 15.90 Fluorite 5-6 Water glass 10
Binding agent 10 Binding agent 10 Binding agent 15 Binding agent 5
Refractory metal ?W 78-84 ????W 78.03- 78.21 M0/W 0.2 ??Ta 2O 5(amounting to) 10.94 ????Nb 11.99
Iron alloy ?Sn ＜0.02 ????Sn 0.02- 0.03 M 0-W 82.06 ??Nb 2O 5(amounting to) 13.64 ????P 0.45
Composition ?Cu ＜0.05 ????As ＜0.04 Sn (0.02 ???Ca 1.09 ????S 0.062
And yield ?S ＜0.07 ????Cu 0.03- 0.06 Cu 0.054 ??SiO 2 14.30 ????F Do not exist
(％) The W direct yield 95-97 The W direct yield 95-98 M 0Direct yield 92.82 The Ta direct yield 92.27 ????Nb/P 27.6
The W direct yield 96.09 The Nb direct yield 94.45 The Nb direct yield 87.97

Claims (9)

1. method that adopts ac plasma stove smelting high melting metal alloy is characterized in that it comprises: system furnace charge ball, drying, plasma furnace are smelted three steps; Wherein
System furnace charge ball process is: refractory metal mineral aggregate, coke powder, auxiliary ingredients mixing are become the furnace charge ball through adhesive bond; Drying process is: make the furnace charge ball of the making dry forming that dries.
The plasma furnace smelting process is: add the working medium that can produce plasma body in plasma furnace, with stove with the ball input, and make it pass arc region to be heated and to fall into burner hearth, the plasma body that carbon and working medium produce carries out smelting reducing reaction generation refractory metal alloy with mineral aggregate.
2. the method for smelting high melting metal alloy according to claim 1 is characterized in that when smelting ferrotungsten, and the used composition of furnace charge ball is in the system furnace charge ball process: WO 3Be 100 parts of the tungsten concentrates of 46.54-66.48%, coke powder 18-25 part of fixed carbon 〉=78%, lime 4-10 part of CaO 〉=75%, CaF 2Be fluorite 1.5-4 part of 94%, Na 2SiO 3Binding agent 5-10 part for 40-50%.
3. the method for smelting high melting metal alloy according to claim 1 is characterized in that when smelting the tungsten iron alloy, and the used composition of furnace charge ball is in the system furnace charge ball process: WO 3Be 100 parts of the tungsten concentrates of 46.54-66.48%, MO is concentrated molybdenum ore 10-21.8 part of 45%, lime 7.5-15.9 part of CaO 〉=75%, coke powder 13-20 part of fixed carbon 〉=78%, Na 2SiO 3Binding agent 5-20 part for 40-50%.
4. the method for smelting high melting metal alloy according to claim 1 is characterized in that when smelting tantalum-niobium alloy, and the used composition of furnace charge ball is in the system furnace charge ball process: Ta 2O 5Tantalum-niobium concentrate or Nb for 1.50-3.00% 2O 5Be 100 parts in the slag of 2-4%, coke powder 10-20 part of fixed carbon 〉=78%, lime 9-12 part of CaO 〉=75%, CaF 2Be fluorite 5-10 part of 94%, Na 2SiO 3Binding agent 5-10 part for 40-50%.
5. the method for smelting high melting metal alloy according to claim 1 is characterized in that when smelting ferrocolumbium, and the used composition of furnace charge ball is Nb in the system furnace charge ball process 2O 5100 parts in the niobium concentrate of 5-20%, coke powder 16-22 part of fixed carbon 〉=78%, lime 3.8-16 part of CaO 〉=75%, Na 2SiO 3Binding agent 5-10 part for 40-50%.
6. according to the method for described any the smelting high melting metal alloy of claim 1-5, it is characterized in that the working medium of the produced plasma body that adds is hydrogen in plasma furnace.
7. plasma furnace that is used for smelting high melting metal, body of heater comprises producer and reactor two portions, producer is conventional circular platform type, producer is provided with the Graphite Electrodes of working medium import, cast feeder and the generation electric arc that can produce plasma body, it is characterized in that three root graphite electrodes are set on circumference the oblique cutting mode of hexagonal angle each other, the producer inwall studs with high temperature resistant furnace lining; Reactor wall is the high temperature material furnace lining that is provided with ring groove, and outer wall is provided with the smoke-uptake that communicates with burner hearth.
8. the plasma furnace of smelting high melting metal according to claim 7 is characterized in that three root graphite electrodes become 0-60 ° of angle with the body of heater horizontal plane.
9. the plasma furnace of smelting high melting metal according to claim 7 is characterized in that the reactor burner hearth is the approximate circle ball-type, and the top of the spaced walls between burner hearth and ring groove has breach.
CN96119824A 1996-09-18 1996-09-18 Method and apparatus for smelting high melting metal by plasma Expired - Fee Related CN1051579C (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1098935C (en) * 1999-11-24 2003-01-15 武汉科技大学 AC plasma melting reduction process and equipment for direct smelting of ferroalloy with very low carbon content
CN103589867A (en) * 2013-11-20 2014-02-19 北京环宇冠川等离子技术有限公司 Method and device for treating ironmaking ash, mud and mill tailings by plasma torch heating technology
CN104745831A (en) * 2013-12-30 2015-07-01 大冶特殊钢股份有限公司 Carbon conductive slag for electroslag steel smelting
CN111333338A (en) * 2019-12-24 2020-06-26 力玄科技(上海)有限公司 Utilize plasma melting furnace to carry out useless resource utilization production line admittedly, useless dangerously

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4082914A (en) * 1973-05-14 1978-04-04 Nikolai Iosifovich Bortnichuk Method of stabilizing arc voltage in plasma arc furnace and apparatus for effecting same
CA1173784A (en) * 1981-07-30 1984-09-04 William H. Gauvin Transferred-arc plasma reactor for chemical and metallurgical applications
AT375404B (en) * 1983-02-03 1984-08-10 Voest Alpine Ag METHOD FOR CARRYING OUT MELTING, MELTING METALURGICAL AND / OR REDUCTION METALURGICAL PROCESSES IN A PLASMA MELTING FURNACE AND DEVICE FOR CARRYING OUT THE METHOD
US4731112A (en) * 1986-02-19 1988-03-15 Midrex International, B.V. Rotterdam, Zurich Branch Method of producing ferro-alloys
CN86106257B (en) * 1986-09-17 1987-12-02 枣庄市化学冶金研究所 Plasma carbothermic method for producing molybdenum iron

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1098935C (en) * 1999-11-24 2003-01-15 武汉科技大学 AC plasma melting reduction process and equipment for direct smelting of ferroalloy with very low carbon content
CN103589867A (en) * 2013-11-20 2014-02-19 北京环宇冠川等离子技术有限公司 Method and device for treating ironmaking ash, mud and mill tailings by plasma torch heating technology
CN104745831A (en) * 2013-12-30 2015-07-01 大冶特殊钢股份有限公司 Carbon conductive slag for electroslag steel smelting
CN111333338A (en) * 2019-12-24 2020-06-26 力玄科技(上海)有限公司 Utilize plasma melting furnace to carry out useless resource utilization production line admittedly, useless dangerously

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