CN107723484A - A kind of crucible of preparation method and application of ferrochrome in this method - Google Patents
A kind of crucible of preparation method and application of ferrochrome in this method Download PDFInfo
- Publication number
- CN107723484A CN107723484A CN201710779922.0A CN201710779922A CN107723484A CN 107723484 A CN107723484 A CN 107723484A CN 201710779922 A CN201710779922 A CN 201710779922A CN 107723484 A CN107723484 A CN 107723484A
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- Prior art keywords
- crucible
- quartz sand
- ferrochrome
- furnace charge
- preparation
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Classifications
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B34/00—Obtaining refractory metals
- C22B34/30—Obtaining chromium, molybdenum or tungsten
- C22B34/32—Obtaining chromium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B5/00—General methods of reducing to metals
- C22B5/02—Dry methods smelting of sulfides or formation of mattes
- C22B5/10—Dry methods smelting of sulfides or formation of mattes by solid carbonaceous reducing agents
-
- 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
Abstract
The present invention relates to a kind of crucible of preparation method and application of ferrochrome in this method, in order to realize that ferrochrome is smelted in microwave heating, while solves technical problem higher to crucible requirement in the method for microwave heating smelting ferrochrome, comprises the following steps：1) dispensing：Furnace charge includes chromite powder, reducing agent, auxiliary material；The percentage by weight of the furnace charge is respectively：Chromite powder is 65 70%, and reducing agent is 15 20%, and auxiliary material is 13 18%；2) ball processed：Each feed powder of furnace charge is well mixed according to proportioning, add water, suppress balling-up, drying；3) pellet is laid on crucible, thickness is no more than 150mm, and then crucible is fitted into micro-wave oven and heated；4) furnace charge after heating is taken out, is broken by water cooling, jaw, Gravity separation, obtains ferrochrome grain.The high carbon ferro-chrome Cr contents that the present invention reduces are 55 60%, and the Cr rate of recovery 85 92% is suitable with traditional mineral hot furnace product index, and reduces power consumption and dust pollution, and economical solves microwave metallurgical furnace charge release problems.
Description
Technical field
The present invention relates to a kind of technique for producing high carbon ferro-chrome, refers in particular to obtain high carbon ferro-chrome with microwave reduction chromite
Method and this method in used crucible.
Technical background
High-carbon chrome alloy is mainly as steel-making additive, for producing stainless steel, tool steel, spring steel, ball bearing
The various special steels such as steel, acid resisting steel, heat resisting steel, improve the high temperature resistance of steel, anti-oxidant, corrosion-resistant, wear-resistant, high intensity property
Energy.Ferrochrome is mainly produced using mineral hot furnace at present, belongs to high energy consumption, high pollution industry.As national requirements for environmental protection is continuous
Upgrading, and under increasingly stricter carbon emission quota system, mine heat furnace smelting ferrochrome technique will progressively withdraw from the market, low energy
Consumption, low stain, the metallurgical technology of low cost are the directions of future development.
Microwave metallurgical is referred to as green metallurgical, be it is developed in recent years it is a kind of smelt new technology, have homogeneous heating,
The features such as firing rate is fast, good energy-conserving effect and pollution are few.In recent years, although the research of microwave high-temperature heating art increasingly by
To concern, a certain degree of commercial application is realized in microwave high-temperature heat resolve and microwave sintering ceramic material etc.,
And good economy is shown, but studied due to microwave smelting mineral resources reaction mechanism and high temperature microwave metallurgical reaction
Hysteresis, especially refractory crucible quality requirement needed for the microwave metallurgical ferrochrome higher to reduction temperature is higher, smelts simultaneously
After the completion of furnace charge and crucible be difficult to depart from, cause by the way of microwave heats to produce ferrochrome being difficult to industrialize.
The content of the invention
Higher to crucible requirement in the method for ferrochrome and stove after the completion of smelting is smelted to solve the heating of existing microwave
The technical problem for being difficult to depart from of material and crucible, an object of the present invention are prepared to provide one kind using microwave reduction chromite
The method of ferrochrome, another object of the present invention for provide can be conveniently stripped after a kind of smelting crucible.The microwave of the present invention
The technique for reducing chromite, energy-saving, carbon emission is relatively low, crucible is convenient in demoulding after smelting.
The present invention technical solution be：
A kind of preparation method of ferrochrome, its difference are to comprise the following steps：
1) dispensing：
Furnace charge includes chromite powder, reducing agent, auxiliary material；The percentage by weight of the furnace charge is respectively：Chromite powder is 65-
70%, reducing agent 15-20%, auxiliary material 13-18%；The reducing agent is semi-coke, and auxiliary material is silica；
2) ball processed：Each feed powder of furnace charge is well mixed according to proportioning, add water, suppress balling-up, drying；
3) pellet is laid on crucible, thickness is no more than 150mm, then crucible is fitted into micro-wave oven, using 20KW
Microwave heats 120-150min, 1500-1550 DEG C of heating-up temperature；
4) pellet after heating is taken out, is broken by water cooling, jaw, Gravity separation, obtains high-carbon chrome alloy grain.
Further, a diameter of 30-50mm of pellet described in step 2).
Further, it is stripped for convenience, crucible structure used is in step 3)：Crucible includes crucible body, coating
Quartz sand layer and graphite bisque in crucible body, the quartz sand layer are coated in crucible body, and the graphite sealing applies
Cloth is on quartz sand layer.
Further, the quartz sand thickness is 50mm, and graphite bisque is 10mm, the quartz sand particle used in quartz sand layer
A diameter of 0.5-2mm.
Further, the crucible body using silica fire resistant it is brick into.
A kind of crucible, including crucible body, the quartz sand layer and graphite bisque that are coated in crucible body, the quartz
Layer of sand is coated in crucible body, and the graphite sealing is coated on quartz sand layer.
Further, the quartz sand thickness is 50mm, and graphite bisque is 10mm, the quartz sand particle used in quartz sand layer
A diameter of 0.5-2mm.
Further, the crucible body using silica fire resistant it is brick into.
Beneficial effect possessed by the present invention：
1st, the high carbon ferro-chrome Cr contents that the present invention reduces are 55-60%, Cr rate of recovery 85-92%, reach traditional industry and refer to
Mark；Relative to traditional mineral hot furnace technique, microwave smelting high carbon ferrochrome, power consumption reduces 30%-40%, and dust reduces 90%,
CO2 discharges reduce 30%；
2nd, addition auxiliary material silica is mainly used to reduce ferrochrome smelting slag melting point in preparation method of the invention.Contain in chromite
There are substantial amounts of MgO, Al2O3, magnesium aluminate spinel can be produced in reduction process, up to more than 2000 DEG C, microwave stove heat is difficult to fusing point
Melted, in smelting process, it will be enriched in mineral aggregate surface, so as to hinder reduction reaction to continue.For that purpose it is necessary to add
A certain amount of auxiliary material, to reduce its fusing point.According to SiO2-MgO-Al2O3Ternary slag phase figure, add the SiO of suitable dose2It can incite somebody to action
Slag melting point control is smelted at 1450-1500 DEG C, is effectively reduced and is continued to react required temperature, saves energy consumption.
3rd, the invention using the demoulding bed material of quartz sand layer and graphite bisque as crucible, good solves
The adhesion problems of microwave metallurgical high temperature furnace charge and refractory crucible, requirement of the microwave metallurgical to refractory material is reduced, is
Microwave smelting high carbon ferrochrome realizes that serialization, industrialized production lay the foundation.Chromite, which is smelted, needs melting furnace slag, is melted after smelting
The clinker melted easily with crucible adhesion, causes alloy to be difficult to collect, while the easy erosion of refractory of metallurgical slag, causes to manufacture crucible
Refractory material service life substantially reduce.Fusing point is up to more than 3000 DEG C under anoxic conditions for graphite, and reactivity is relatively low, high temperature
Do not allow easy-sintering, be refractory to clinker, isolation clinker and alloy can be played, prevent it from being contacted with refractory material.Graphite is inhaled simultaneously
It is good to receive microwave property, it is ensured that furnace charge bottom temp reaches reaction and required.Quartz sand will not be heated by microwave, graphite bisque
Underlay quartz sand can play temperature buffer effect, reduce refractory temperatures, while quartz sand layer can reduce microwave to fire resisting
The injury of material, substantially reduce quality requirement of the microwave metallurgical to refractory material.Alloy and clinker can be light after the completion of smelting
Separated from graphite linings.Simultaneously quartz sand, graphite powder by separating, dry after it is reusable.
Brief description of the drawings
Fig. 1 is present invention process flow chart；
Fig. 2 is the structural representation that the present invention uses crucible.
Embodiment
As shown in figure 1, a kind of process chart of the preparation method of ferrochrome is：
1) dispensing：Furnace charge includes chromite powder, reducing agent, auxiliary material；The percentage by weight of the furnace charge is respectively：Chromite powder
For 65-70%, reducing agent 15-20%, auxiliary material 13-18%；The reducing agent is semi-coke, and auxiliary material is silica；The present invention's
Auxiliary material silica is added in preparation method to be mainly used to reduce ferrochrome smelting slag melting point.Contain substantial amounts of MgO, Al in chromite2O3,
Magnesium aluminate spinel can be produced in reduction process, fusing point is up to more than 2000 DEG C, and microwave stove heat is difficult to be melted, smelting process
In, it will be enriched in mineral aggregate surface, so as to hinder reduction reaction to continue.For that purpose it is necessary to a certain amount of auxiliary material is added, with drop
Its low fusing point.According to SiO2-MgO-Al2O3Ternary slag phase figure, add the SiO of suitable dose2Slag melting point control can will be smelted to exist
1450-1500 DEG C, effectively reduce and continue to react required temperature, save energy consumption.
2) ball processed：The feed powder of the proportioning is well mixed, adds water, suppresses balling-up, drying, a diameter of 30- of pellet
50mm；
3) pellet is laid on crucible, thickness is no more than 150mm, and the crucible is fitted into micro-wave oven, uses
20KW microwaves heat 120-150min, 1500-1550 DEG C of heating-up temperature；Furnace charge, water cooling are taken out, jaw is broken, and Gravity separation, obtains height
Carbon ferrochrome grain.
Example below is carried out in 20KW micro-wave ovens, and relevant material composition is shown in Table 1.
Table 1：Test raw material composition
Embodiment 1：Chromite powder 1960g, semi-coke powder 510g, Cab-O-sil 430g, after being mixed, adds hydraulic pressure that diameter 30mm is made
Pellet, in 105 DEG C of drying；Refractory crucible middle berth 50mm quartz sand+10mm graphite powders.Drying pellet is layered on graphite bisque
On；20KW microwave rates are sent into, 140min is heated, obtains alloy 1032g, wherein Cr：57.12%, Si1.37%, C7.5%, Cr
The rate of recovery 85.3%.
Embodiment 2：Chromite powder 2162g, semi-coke powder 562g, Cab-O-sil 476g, after being mixed, adds hydraulic pressure that diameter 50mm is made
Pellet, in 105 DEG C of drying；Refractory crucible middle berth 50mm quartz sand+10mm graphite powders.Drying pellet is layered on graphite bisque
On；20KW microwave rates are sent into, 150min is heated, obtains alloy 1178g, wherein Cr：57.26%, Si1.43%, C8.1%, Cr
The rate of recovery 88.5%.
Embodiment 3：Chromite powder 1554g, semi-coke powder 404g, Cab-O-sil 342g, after being mixed, adds hydraulic pressure that diameter 30mm is made
Pellet, in 105 DEG C of drying；Refractory crucible middle berth 50mm quartz sand+10mm graphite powders.Drying pellet is layered on graphite bisque
On；20KW microwave rates are sent into, 120min is heated, obtains alloy 893g, wherein Cr：55.52%, Si1.13%, C6.9%, Cr are returned
Yield 92.1%.
Embodiment 4：The long crucible structure schematic diagram of the present invention is illustrated in figure 2, crucible includes crucible body 1, is coated on earthenware
Quartz sand layer 2 and graphite bisque 3 on crucible body, quartz sand layer is coated in crucible body, and graphite sealing is coated on quartz sand
On layer.Quartz sand thickness is 50mm, and graphite bisque is 10mm, a diameter of 0.5-2mm of quartz sand particle used in quartz sand layer.Earthenware
Crucible body using silica fire resistant it is brick into.
The present invention uses the demoulding bed material of quartz sand layer and graphite bisque as crucible, and good solves in microwave metallurgical
The adhesion problems of high-temp. furnace material and refractory crucible, requirement of the microwave metallurgical to refractory material is reduced, smelted for microwave high
Carbon ferrochrome realizes that serialization, industrialized production lay the foundation.Chromite, which is smelted, needs melting furnace slag, and the clinker melted after smelting is easy
With crucible adhesion, alloy is caused to be difficult to collect, while the easy erosion of refractory of metallurgical slag, cause the refractory material for manufacturing crucible
Service life substantially reduces.For fusing point up to more than 3000 DEG C, reactivity is relatively low under anoxic conditions for graphite, and high temperature is not easy to burn
Knot, is refractory to clinker, can play isolation clinker and alloy, prevent it from being contacted with refractory material.Graphite absorbs microwave simultaneously
Can be good, it is ensured that furnace charge bottom temp reaches reaction and required.Quartz sand will not be heated by microwave, graphite bisque underlay quartz
Sand can play temperature buffer effect, reduce refractory temperatures, while quartz sand layer can reduce wound of the microwave to refractory material
Evil, substantially reduces quality requirement of the microwave metallurgical to refractory material.Alloy and clinker can be easily from graphite linings after the completion of smelting
Upper separation.Simultaneously quartz sand, graphite powder by separating, dry after it is reusable.
Claims (8)
1. a kind of preparation method of ferrochrome, it is characterised in that comprise the following steps：
1) dispensing：
Furnace charge includes chromite powder, reducing agent, auxiliary material；The percentage by weight of the furnace charge is respectively：Chromite powder is 65-70%,
Reducing agent is 15-20%, auxiliary material 13-18%；The reducing agent is semi-coke, and auxiliary material is silica；
2) ball processed：Each feed powder of furnace charge is well mixed according to proportioning, add water, suppress balling-up, drying；
3) pellet is laid on crucible, thickness is no more than 150mm, and then crucible is fitted into micro-wave oven, using 20KW microwaves
Heat 120-150min, 1500-1550 DEG C of heating-up temperature；
4) furnace charge after heating is taken out, is broken by water cooling, jaw, Gravity separation, obtains ferrochrome grain.
2. the preparation method of ferrochrome according to claim 1, it is characterised in that：Pellet is a diameter of described in step 2)
30-50mm。
3. the preparation method of ferrochrome according to claim 1 or 2, it is characterised in that：Crucible used in step 3)
Structure is：Crucible includes crucible body, the quartz sand layer and graphite bisque being coated in crucible body, the quartz sand layer coating
In crucible body, the graphite sealing is coated on quartz sand layer.
4. the preparation method of ferrochrome according to claim 3, it is characterised in that：The quartz sand thickness is 50mm,
Graphite bisque is 10mm, a diameter of 0.5-2mm of quartz sand particle used in quartz sand layer.
5. the preparation method of ferrochrome according to claim 4, it is characterised in that：The crucible body is using siliceous resistance to
Firebrick is built into.
6. the crucible used in a kind of preparation method of any ferrochrome of claim 1-4, it is characterised in that：Earthenware
Crucible includes crucible body, the quartz sand layer and graphite bisque being coated in crucible body, and the quartz sand layer is coated on crucible sheet
On body, the graphite sealing is coated on quartz sand layer.
7. crucible according to claim 6, it is characterised in that：The quartz sand thickness is 50mm, and graphite bisque is 10mm,
The a diameter of 0.5-2mm of quartz sand particle used in quartz sand layer.
8. crucible according to claim 7, it is characterised in that：The crucible body using silica fire resistant it is brick into.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201710779922.0A CN107723484B (en) | 2017-09-01 | 2017-09-01 | Preparation method of ferrochrome and crucible applied to preparation method |
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| CN201710779922.0A CN107723484B (en) | 2017-09-01 | 2017-09-01 | Preparation method of ferrochrome and crucible applied to preparation method |
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| CN107723484A true CN107723484A (en) | 2018-02-23 |
| CN107723484B CN107723484B (en) | 2020-01-14 |
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Cited By (2)
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| CN108913897A (en) * | 2018-08-06 | 2018-11-30 | 王德清 | A kind of energy conservation ferrochrome production method |
| WO2019169862A1 (en) * | 2018-03-08 | 2019-09-12 | 盐城市鑫洋电热材料有限公司 | Method for preparing ferrochrome alloy from chromite |
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