CN1207246C - Method for producing electric smelting calcium zirconate - Google Patents
Method for producing electric smelting calcium zirconate Download PDFInfo
- Publication number
- CN1207246C CN1207246C CN 01145519 CN01145519A CN1207246C CN 1207246 C CN1207246 C CN 1207246C CN 01145519 CN01145519 CN 01145519 CN 01145519 A CN01145519 A CN 01145519A CN 1207246 C CN1207246 C CN 1207246C
- Authority
- CN
- China
- Prior art keywords
- calcium zirconate
- calcite
- ratio
- zirconium dioxide
- electric
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- DJOYTAUERRJRAT-UHFFFAOYSA-N 2-(n-methyl-4-nitroanilino)acetonitrile Chemical compound N#CCN(C)C1=CC=C([N+]([O-])=O)C=C1 DJOYTAUERRJRAT-UHFFFAOYSA-N 0.000 title claims abstract description 42
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 19
- 238000003723 Smelting Methods 0.000 title claims abstract description 18
- MCMNRKCIXSYSNV-UHFFFAOYSA-N ZrO2 Inorganic materials O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 claims abstract description 13
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 claims abstract description 11
- 229910021532 Calcite Inorganic materials 0.000 claims abstract description 10
- 239000000203 mixture Substances 0.000 claims abstract description 10
- 238000002844 melting Methods 0.000 claims abstract description 9
- 230000008018 melting Effects 0.000 claims abstract description 9
- 239000000126 substance Substances 0.000 claims abstract description 6
- 238000010891 electric arc Methods 0.000 claims abstract description 5
- 238000007670 refining Methods 0.000 claims description 8
- 238000000227 grinding Methods 0.000 claims description 7
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 6
- 239000002245 particle Substances 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 5
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 3
- 240000001949 Taraxacum officinale Species 0.000 claims description 2
- 235000006754 Taraxacum officinale Nutrition 0.000 claims description 2
- 235000005187 Taraxacum officinale ssp. officinale Nutrition 0.000 claims description 2
- 238000005336 cracking Methods 0.000 claims description 2
- 239000010419 fine particle Substances 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims description 2
- 238000009749 continuous casting Methods 0.000 abstract description 13
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 abstract description 8
- 239000000463 material Substances 0.000 abstract description 8
- 230000000694 effects Effects 0.000 abstract description 6
- 229910052786 argon Inorganic materials 0.000 abstract description 4
- 230000008021 deposition Effects 0.000 abstract description 3
- 238000005266 casting Methods 0.000 abstract description 2
- 238000007664 blowing Methods 0.000 abstract 1
- 239000000470 constituent Substances 0.000 abstract 1
- 230000002265 prevention Effects 0.000 abstract 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract 1
- 229910000831 Steel Inorganic materials 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- 239000010959 steel Substances 0.000 description 8
- 230000008569 process Effects 0.000 description 4
- 229910004298 SiO 2 Inorganic materials 0.000 description 3
- 238000007654 immersion Methods 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 238000009628 steelmaking Methods 0.000 description 3
- 229910000655 Killed steel Inorganic materials 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000011575 calcium Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 241000196324 Embryophyta Species 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- XFWJKVMFIVXPKK-UHFFFAOYSA-N calcium;oxido(oxo)alumane Chemical compound [Ca+2].[O-][Al]=O.[O-][Al]=O XFWJKVMFIVXPKK-UHFFFAOYSA-N 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000006253 efflorescence Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000005350 fused silica glass Substances 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000011017 operating method Methods 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 206010037844 rash Diseases 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
Landscapes
- Compositions Of Oxide Ceramics (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The present invention relates to a method for producing calcium zirconate, particularly to a method for producing electric smelting calcium zirconate. The monoclinic zirconium dioxide of high content and calcite are uniformly mixed according to a certain weight proportion, the mixture is placed in an electric arc furnace, a certain of voltage and a certain of electric current are switched on, the mixture is heated to be melted, and the melted mixture is refined and is blown into balls with compressed air or is cast into blocks; the content of the monoclinic zirconium dioxide is higher than 97%, the purity of the calcite is higher than 54%, and the ratio of the weight portion of the monoclinic zirconium dioxide to the calcite is (60 to 45): (35 to 50); the furnace temperature is from 2250 to 2300 DEG C, the ratio of ZrO2 to CaO in the chemical constituents of the generated calcium zirconate is not less than 2.3 and is not more than 3.3, the quality of the electric melting calcium zirconate is stable, the calcium zirconate is used as the inner lining material of an immersing water opening for preventing AL2O3 deposition without argon blowing, the clogging prevention effect is obvious, and the continuous casting times are as high as ten casting times. The electric smelting calcium zirconate has the advantages of simple production method, low cost, obvious economic benefit and easy popularization.
Description
(1) technical field: the present invention relates to a kind of production method of calcium zirconate, particularly relate to a kind of production method of electric smelting calcium zirconate.
(2) background technology: calcium zirconate is a kind of novel refractory materials, and its fusing point is 2200～2300 ℃, and it is to generally acknowledge the most effective a kind of inner lining refractory that prevents submerged nozzle obstruction and alumina deposit at present both at home and abroad.
The steel-making of ferrous metal develops to continuous casting process, and submerged nozzle is a functional refractory quite crucial during steel-making continuous casting is produced, the good and bad quality and the continuous casting operating procedure that directly influences steel billet of its performance, and production cost height.It is the economic target that the quality of submerged nozzle performance is related to steel-making continuous casting technology.Production practice prove, when some special steels of continuous casting or aluminium killed steel, and used AL
2O
3-C mass immersion type sprue can produce AL
2O
3The dross phenomenon causes the Molten Steel Flow instability, even causes the mouth of a river to stop up fully, has influenced the normal cast that continuous casting is produced, and causes bigger financial loss, and has influenced billet quality.In order to solve in the continuous casting process because AL
2O
3The dross problem, the scientific worker develops the anti-AL of various ways in recent years
2O
3The technical measures at the deposition dross mouth of a river as slit Argon submerged nozzle, change the section-differential immersion mouth of a river of mouth of a river internal diameter and are compounded with submerged nozzle of anti-clogging plug material or the like.But the first two plants mouth of a river manufacturing process complexity, uses very inconveniently, and operation easier is higher, and on the contrary the anti-clogging plug material mouth of a river is easy relatively, and anti-blocking material has O '-ZrO
2, CaO-Mgo-Al
2O
3, BN-AIN-C, SiC-BN-C, ZrO
2-CaO-C etc., wherein ZrO
2-CaO (CaZrO
3) material is because cost is lower, and the anti-clogging plug effect is remarkable, the CaO component has certain cleaning action to molten steel simultaneously, so be subjected to domestic and international attention especially.Domestic when cast aluminum killed steel, adopt the fused quartz matter mouth of a river mostly, shortcoming is that resistance to fouling is poor, and the continuous casting heat is low, and makes molten steel bring impurity into easily, can not better satisfy the continuous casting requirement, adopt the Argon formula mouth of a river, effect is also undesirable, and cost is also high, domestic certain research institute produces calcium zirconate with sintering process, about 1600 ℃ of synthesis temperature, around connection synthetic calcium zirconate result of use still can, but synthesis technique complexity, sintering repeatedly, grinding, moulding, cost is higher, its selling price and import material are similar, and competitiveness of product is restricted.
(3) summary of the invention: the objective of the invention is to simplify production technique, reduce production costs, the production method of real electric smelting calcium zirconate.
Technical scheme of the present invention is: a kind of production method of electric smelting calcium zirconate, with the ratio of weight part 43～63: 37～57 monoclinic zirconium dioxide and calcite, or with the ratio of weight part 43～63: 37～57 monoclinic zirconium dioxide and light calcium carbonate, mixing drops in the electric arc furnace one by one, the energising fusing of heating, be to carry out melting under 2200～2300 ℃ the condition in furnace temperature, refining, blow ball or pour into piece with the pressurized air turndown at last, the ratio of relative weight part satisfies 2.3≤ZrO in the Chemical Composition that generates calcium zirconate
2/ CaO≤3.3.
ZrO in the Chemical Composition that generates calcium zirconate
2The ratio of preferred relative weight part of/CaO is 2.67, the purity of monoclinic zirconium dioxide is more than 97%, calcite purity is more than 54%, the particle size after cracking of calcite is below the 4mm, the melting voltage of heating is 80～120 volts, and electric current is 2000～4000 peaces, and smelting time is 0.5～1.5 hour, it is 6～10Kg/cm that the ball air pressure is blown in refining 3～6 minutes, turndown
2, the calcium zirconate liquation that refining is good, winding-up balling-up granular particle, or pulverize after pouring into piece.
Become 40 orders with being ground into granular calcium zirconate input pulverizer grinding after jetting into the calcium zirconate of hollow ball or pouring into piece, or 100 orders, or 200 orders, or 325 purpose fine particles.
The present invention has useful positively effect.
(1) produce calcium zirconate with the electric smelting method, material is closely knit, and steady quality is reliable, and its electric smelting calcium zirconate product is used for the not anti-AL of Argon through domestic relevant producer
2O
3Deposition submerged nozzle inner lining material, the anti-clogging plug effect is remarkable.Continuous casting reaches 10 heats, and the general 6-7 heat of the calcium zirconate continuous casting that sintering process is made, and former AL
2O
3-C matter immersion mouthful continuous casting has only the 2-3 heat.
It is as follows that the electric smelting calcium zirconate product detects its contained composition through domestic units concerned:
| Chemical Composition % | Mineral composition % | ||||||
| ZrO 2 | CaO | SiO 2 | Al 2O 3 | Fe 2O 3 | TiO 2 | Calcium zirconate | ZrO 2 |
| 69.98 | 25.85 | 2.11 | 0.82 | 0.14 | 0.18 | 70.0 | 30.0 |
As can be seen from the above table, SiO
2Keep 1～2%, for generating the low melt-phase of sial calcium that fusing point more is lower than calcium aluminate, more favourable, the effect that suppresses the calcium zirconate aquation is also arranged simultaneously, facts have proved that this submerged nozzle inside made from electric smelting calcium zirconate on the surface of contact molten steel, is the tiny ZrO that distributing in the low melting point phase matrix
2So particle is SiO
2Height a bit gains everything and lose nothing.Be CaZrO
3Under casting temperature with molten steel in Al
2O
3Effect generates CaO-Al
2O
3-ZrO
2Three component system low melting point phase, and, eliminate stop and deposition in the stop of mouth of a river inwall with flowing away that steel flows.
Prove that after further study product assurance of the present invention does not produce on the problem of aquation, to ZrO
2The ratio of/CaO compares, and its theoretical value is 2.14.If ratio value＜2.14 then can produce free CaO, this moment, CaO can absorb airborne moisture, became Ca (OH)
2Absorb airborne CO again
2, become CaCO
3, cause efflorescence, so when producing electric smelting calcium zirconate, ZrO
2/ CaO ratio maximum should be greater than more than 2.3, and product could be stablized, and reaches as high as 3.3 by ratio.Preferred values is about 2.67.Here it is ZrO
2Be not less than 69%, CaO is not higher than 30%, calcium zirconate content between 70%～80%, cube ZrO
2Between 30～20%, then free CaO can not exist, and guarantees CaZrO
3Quality.
(2) the simple cost of electric smelting method production calcium zirconate production method is low, and remarkable in economical benefits receives praises from customers, penetration and promotion easily.
(4) embodiment
Embodiment one, and the content of getting 54.1kg is at the monoclinic zirconium dioxide (ZrO more than 97%
2), get the light calcium carbonate of 45.9kg, drop in the V-Mixer and mixed 10～15 minutes, the back discharging that is mixed once drops in the electric arc furnace, 116 volts of voltages, electric current 2500 peaces, the fusing melting of heating, temperature reaches about 2300 ℃, melting 50 minutes, refining 5 minutes, turndown is used 8kg/cm then
2High-pressure air jet into the hollow ball particle, collect calcium zirconate hollow ball product in collection ball chamber, by 4 mesh sieves dropping into the ball mill grinding less than 5mm calcium zirconate hollow ball, become 40 orders by the customer requirements grinding, or 100 orders, or 200 orders, or the calcium zirconate powder of 325 purpose all sizes.
Embodiment two: get the monoclinic zirconium dioxide hollow ball 57.2kg more than 97%, calcite granularity (2～4mm) 42.8kg, in mixer, be mixed, every 100kg is a unit that drops into electric arc furnace, 98 volts of voltages, electric current 2000 peaces, temperature can reach 2300 ℃, melted 1 hour, refining was poured in the water-cooled press mold after 5 minutes, naturally cool to normal temperature then, take out block calcium zirconate,, become 40 orders according to the customer requirements grinding with dropping into the ball mill grinding after the crusher in crushing, 100 orders, 200 orders, powders such as 320 orders, finished product warehouse-in.
Claims (3)
1. the production method of an electric smelting calcium zirconate, it is characterized in that: be 43～63: 37～57 monoclinic zirconium dioxide and calcite with the ratio of weight part, or with the ratio of weight part 43～63: 37～57 monoclinic zirconium dioxide and light calcium carbonate, mixing drops in the electric arc furnace one by one, the energising fusing of heating, be to carry out melting under 2200～2300 ℃ the condition in furnace temperature, refining, blow ball or pour into piece with the pressurized air turndown at last, the ratio of relative weight part satisfies 2.3≤ZrO in the Chemical Composition that generates calcium zirconate
2/ CaO≤3.3.
2. the production method of electric smelting calcium zirconate according to claim 1 is characterized in that: ZrO in the Chemical Composition that generates calcium zirconate
2The ratio of preferred relative weight part of/CaO is 2.67, the purity of monoclinic zirconium dioxide is more than 97%, calcite purity is more than 54%, the particle size after cracking of calcite is below the 4mm, the melting voltage of heating is 80～120 volts, and electric current is 2000～4000 peaces, and smelting time is 0.5～1.5 hour, it is 6～10Kg/cm that the ball air pressure is blown in refining 3～6 minutes, turndown
2, the calcium zirconate liquation that refining is good, winding-up balling-up granular particle, or pulverize after pouring into piece.
3. the production method of electric smelting calcium zirconate according to claim 1 and 2, it is characterized in that: be ground into granular calcium zirconate input pulverizer grinding after will jetting into the calcium zirconate of hollow ball or pouring into piece and become 40 orders, or 100 orders, or 200 orders, or 325 purpose fine particles.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 01145519 CN1207246C (en) | 2001-11-21 | 2001-12-27 | Method for producing electric smelting calcium zirconate |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN01138206 | 2001-11-21 | ||
| CN01138206.6 | 2001-11-21 | ||
| CN 01145519 CN1207246C (en) | 2001-11-21 | 2001-12-27 | Method for producing electric smelting calcium zirconate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1420103A CN1420103A (en) | 2003-05-28 |
| CN1207246C true CN1207246C (en) | 2005-06-22 |
Family
ID=25740604
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 01145519 Expired - Lifetime CN1207246C (en) | 2001-11-21 | 2001-12-27 | Method for producing electric smelting calcium zirconate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1207246C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102007010173B4 (en) * | 2007-02-28 | 2009-04-16 | Refractory Intellectual Property Gmbh & Co. Kg | Melt-cast refractory product |
| CN105482506A (en) * | 2015-12-10 | 2016-04-13 | 陕西理工学院 | Vanadium-doped calcium zirconate inorganic pigment and preparing method thereof |
| CN106830075B (en) * | 2017-02-23 | 2018-06-19 | 武汉科技大学 | A kind of high-purity zirconic acid calcium material and preparation method thereof |
| CN108726566A (en) * | 2018-07-27 | 2018-11-02 | 孙志成 | A kind of high-purity zirconic acid calcium material and preparation method thereof of low cost |
-
2001
- 2001-12-27 CN CN 01145519 patent/CN1207246C/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| CN1420103A (en) | 2003-05-28 |
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| CF01 | Termination of patent right due to non-payment of annual fee |
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Correction item: cessation of patent right due to non-payment of the annual fee Correct: Revocation of the patent right False: Patent right to terminate Number: 11 Volume: 28 |
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| ERR | Gazette correction |
Free format text: CORRECT: CESSATION OF PATENT RIGHT DUE TO NON-PAYMENT OF THE ANNUAL FEE; FROM: CESSATION OF PATENT RIGHT DUE TO NON-PAYMENT OF THE ANNUAL FEE TO: REVOCATION CESSATION OF PATENT RIGHT DUE TO NON-PAYMENT OF THE ANNUAL FEE |
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| ASS | Succession or assignment of patent right |
Owner name: ZHENGZHOU ZHENZHONG FUSED NEW MATERIAL CO., LTD. Free format text: FORMER OWNER: ZHENGZHOU ZHENZHONG ELECTRIC ZIRCONIUM MELTING INDUSTRY CO., LTD. Effective date: 20140504 |
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| C41 | Transfer of patent application or patent right or utility model | ||
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Effective date of registration: 20140504 Address after: Xinmi City, Henan province 452384 small Liu Zhaicun Gou Town Hall Patentee after: ZHENGZHOU ZHENZHONG FUSED ZIRCONIA CO.,LTD. Address before: 888 mailbox 452384, Henan City, Xinmi Province Patentee before: Zhengzhou Zhenzhong Fused Zirconia Co.,Ltd. |
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