CN104072162A - Preparation method of tabular corundum with high volume density - Google Patents
Preparation method of tabular corundum with high volume density Download PDFInfo
- Publication number
- CN104072162A CN104072162A CN201410276547.4A CN201410276547A CN104072162A CN 104072162 A CN104072162 A CN 104072162A CN 201410276547 A CN201410276547 A CN 201410276547A CN 104072162 A CN104072162 A CN 104072162A
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- China
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- balling
- preparation
- volume density
- diamond spar
- plate diamond
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Abstract
The invention discloses a preparation method of tabular corundum with high volume density. The preparation method comprises the following steps: dissolving one of magnesium nitrate, magnesium chloride or magnesium sulfate into water to obtain a balling liquid, performing balling on gamma-Al2O3 fine powder by using the balling liquid, and sequentially performing drying, calcining and cooling molding on an obtained ball material to obtain tabular corundum with high volume density, wherein the particle size of more than 95% of powder in percentage by mass in the gamma-Al2O3 fine powder is not greater than 325 meshes. By adopting the preparation method disclosed by the invention, tabular corundum of which the volume density reaches 3.68g/cm<3> can be prepared, and the apparent porosity of tabular corundum is less than 2.0%; the preparation method can be used for improving indexes such as slag resistance, wear resistance and mechanical strength of refractory products.
Description
Technical field
The present invention relates to fire resisting material field, be specifically related to the preparation method of the plate diamond spar that a kind of volume density is high.
Background technology
Plate diamond spar belongs to high-grade high-purity refractory raw material, its Al
2o
3content is more than 99%, and plate diamond spar has the crystal microstructure of en plaque, is the alundum that a kind of volume density is high, pore is little and the hole of holding one's breath is more.
Plate diamond spar has the features such as refractoriness is high, wear resistance good, resistance to fouling is good, can be used as the main raw material of the refractory materialss such as aluminium carbonaceous, magnalium carbonaceous, magnalium carbonaceous, magnesia spinel matter, magnalium matter, is widely used in the industries such as iron and steel, casting, pottery.
Early stage plate diamond spar starts development by Alcoa the thirties in 20th century, adopts the commercial alumina sintering preparation under the ultra-high temperature condition of the temperature a little less than its fusing point (i.e. 1925 DEG C of left and right) after fine grinding, balling-up after pre-burning.This alundum price is cheap compared with electric capacity corundum, and no matter aspect purity, or sintering character and hot properties aspect are all better than fused corundom, therefore, are used widely.Domestic current You Duo company also starts development and production sintering plate corundum, breaks the monopolization of import plate diamond spar.
Along with steel industry variation with rapid changepl. never-ending changes and improvements, the performance of refractory materials is proposed to higher requirement, correspondingly raw-material performance is also proposed to new requirement, as the performance requriements of functional materials in order to use such as three-major-items for continuous casting (integral stopper rod, long nozzle and submerged nozzle), slide bricks, plate diamond spar is proposed to the more requirement of high volume density.
Application publication number is the preparation technology that the patent of invention document of CN102503448A discloses a kind of sintering plate corundum, comprise raw material fine grinding → balling-up → dry → steps such as sintering → fragmentation → finished product, described balling-up operation comprises the steps: that the abrasive dust that raw material is refined to gained is first by disk balling-up, and the diameter control of balling-up is between 8～15mm; Balling-up is sent in cylinder nodulizer and made it continue to grow to diameter between 18～27mm; In balling-up process, intermittent sprinkling balling-up liquid, described balling-up liquid comprises aluminium glue and phosphoric acid.
Adopt the volume density>=3.55g/cm of the prepared plate diamond spar of the disclosed method of this patent of invention document
3, apparent porosity <5%.
Granted publication number is that the patent of invention document of CN100439289B discloses a kind of processing method that adopts ultra-high temperature shaft kiln to produce sintering plate corundum, chooses low sodium high purity pre-burning aluminum oxide powder AL
2o
3>98.5% is raw material, first through grinding, balling-up and dry, then pellet is sent in high temperature vertical kiln and calcined within the scope of 1850～1920 DEG C, be incubated 1～1.5 hour, after twice ventilation is cooling, temperature while making pellet arrive discharge port is down to below 80 DEG C, and the pellet burning till is finished product through broken processing and screening again.Adopting the volume density of the plate diamond spar that the disclosed method of this patent of invention document burns till is 3.58～3.62g/cm
3, apparent porosity <5%.
At present, on market the volume density of common plate diamond spar generally at 3.50～3.60g/cm
3between, apparent porosity generally, between 3.0～5.0%, can not meet the demand of some application scenario.
In prior art, balling-up liquid adopts high-purity aluminium glue and phosphoric acid preparation conventionally, if Granted publication number is that in the balling-up liquid adopting in the patent of invention document of CN100439289B, rafifinal gum concentration is 0.3%, phosphoric acid concentration is 0.15%, and adopting the volume density of the goods that this balling-up liquid obtains is 3.58～3.62g/cm
3.
Further preferably, in described balling-up liquid, the mass ratio of solute and water is 0.5～2:1.Most preferably, in described balling-up liquid, the mass ratio of solute and water is 1～1.5:1.
The balling-up liquid that the present invention uses contributes to the carrying out of balling-up process on the one hand, improve the density of work in-process (product before calcining), on the other hand in the process of high-temperature calcination, solute (magnesium nitrate, magnesium chloride or magnesium sulfate) in balling-up liquid can be decomposed into magnesium oxide, magnesium oxide can accelerating oxidation aluminium sintering, make the volume density of the plate diamond spar preparing high, apparent porosity is low, can be used in high-grade refractory product.
Described γ-Al
2o
3the balling-up of fine powder comprises a balling-up and the secondary balling-up carried out successively, the ball material particle diameter that a balling-up obtains is 8～12mm, the ball material particle diameter that secondary balling-up obtains is 25～35mm, in whole balling-up process, apply continuously balling-up liquid, the mass ratio of the quality of balling-up liquid used and ball material is 16～25:100.
A balling-up can adopt pan-pelletizer, and secondary balling-up can adopt balling-up cylinder, and in whole balling-up process, continuous uniform sprays balling-up liquid.
Described being dried comprises primary drying and the redrying of carrying out successively, and the temperature of primary drying is 150～200 DEG C, residual water-content <5% in ball material after primary drying; The temperature of redrying is 450～650 DEG C, residual water-content 1% in ball material after redrying.
As preferably, the temperature of described calcining is 1800～2000 DEG C.The time of described calcining is 1～3h.Further preferably, the temperature of described calcining is 1850～1950 DEG C.The time of described calcining is 1.5～2.5h.
Adopt preparation method provided by the invention can prepare volume density up to 3.68g/cm
3above plate diamond spar, apparent porosity is less than 2.0%, can improve the indexs such as slag resistance, wear resistance and the physical strength of refractory product.
Summary of the invention
The invention provides the preparation method of the plate diamond spar that a kind of volume density is high, apparent porosity can be obtained low, the plate diamond spar that volume density is high, the refractory product that adopts gained plate diamond spar to prepare can improve the performances such as compactness, slag resistance, wear resistance and the physical strength of refractory product to a great extent.
A preparation method for the plate diamond spar that volume density is high, comprises the following steps: by water-soluble the one in magnesium nitrate, magnesium chloride or magnesium sulfate, obtain balling-up liquid, adopt this balling-up liquid to carry out γ-Al
2o
3the balling-up of fine powder, gained ball material drying, calcining, cooling forming successively, obtains the described high plate diamond spar of volume density.
Described γ-Al
2o
3fine powder adopts industrial γ-Al
2o
3ball milling obtains, described industrial γ-Al
2o
3in the weight percentage of each composition be respectively Al
2o
3>=98.5%, SiO
2≤ 0.04%, CaO≤0.1%, Fe
2o
3≤ 0.2%, Na
2o≤0.4%.Industry γ-Al
2o
3more than 90% particle diameter of middle massfraction is-60 orders.
Described γ-Al
2o
3fine powder also can directly be buied, the γ-Al directly buying
2o
3in fine powder, the mass percent of each composition is with industrial γ-Al
2o
3require consistent.
As preferably, described γ-Al
2o
3in fine powder, more than 95% powder particle size of massfraction is-325 orders.Be described γ-Al
2o
3fine powder can account for γ-Al by the quality of 325 orders (44um) sieve part
2o
3the more than 95% of fine powder total mass.This means γ-Al
2o
3the particle diameter major part of fine powder is all less than 44um, is convenient to the homogeneity of follow-up balling-up.
As preferably, in described balling-up liquid, the mass ratio of solute and water is 0.5～3:1, and described solute is the one in magnesium nitrate, magnesium chloride or magnesium sulfate.
Embodiment
Embodiment 1
A preparation method for the plate diamond spar that volume density is high, its technical process is:
(1) choose raw material
Choose industrial γ-Al
2o
3, industrial γ-Al
2o
3middle granularity is massfraction>=90.0% of-60 orders (250um), and each composition weight percentage is respectively Al
2o
3>=98.5%, SiO
2≤ 0.04%, CaO≤0.1%, Fe
2o
3≤ 0.2%, Na
2o≤0.4%.
In the present invention, if no special instructions, percentage ratio is weight percentage.
(2) grind
Industrial γ-Al that step (1) is chosen
2o
3put into tuber grinder and dry grind, mill ball proportioning is large ball (diameter 50mm): bead (diameter 30mm)=1:4, and inlet amount is 95kg/h, grading machine rotating speed is 900r/min, the γ-Al of output
2o
3the granularity of fine powder is controlled at-325 order>=95%.
(3) configuration balling-up liquid
In pure water, add magnesium sulfate, stir, be configured to balling-up liquid, in balling-up liquid, the massfraction of magnesium sulfate is 0.5%.
(4) balling-up
γ-the Al obtaining after grinding
2o
3fine powder first adopts a balling-up of disk, and once becoming spherical diameter is 10mm, and the ball material obtaining after a balling-up carries out secondary balling-up by balling-up cylinder again, and it is 25mm that secondary becomes spherical diameter.In whole balling-up process, spray continuously balling-up liquid, the add-on of balling-up liquid is 19% (quality of the ball material even obtaining after secondary balling-up is 100kg, and the add-on of balling-up liquid is 19kg).
(5) dry
The pellet that the hot blast that utilizes the cooling generation of finished product obtains after to step (4) secondary balling-up carries out primary drying, and hot blast temperature is 180 DEG C of left and right, ball material residual water-content <5% after drying; Then utilize shaft furnace smoke evacuation hot blast further to carry out redrying to pellet, hot blast temperature, 520 DEG C of left and right, is dried rear ball material residual water-content <1.0%.
(6) high temperature sintering
Dried pellet is placed in shaft furnace high-temperature calcination, and temperature is 1900 DEG C of left and right, calcination time 2 hours.
(7) cooling
Pass into high pressure cold wind by shaft furnace clinkering zone bottom, make the ball after burning till cooling fast.
(8) inspection
Ball to kiln discharge is tested, main test ball burn till quality, detect ball and whether have burning or raw burn phenomenon.
(9) processing, packaging
The corundum ball being up to the standards is carried out to fragmentation, the particle that fragmentation is good is tested, qualified product packaging warehouse-in.
Embodiment 2～9
Adopt the preparation method identical with embodiment 1 to prepare plate diamond spar, difference is the composition of balling-up liquid, and the composition of balling-up liquid is as shown in table 1.
Table 1
| ? | Solute | The massfraction of solute |
| Embodiment 2 | Magnesium sulfate | 1.5 |
| Embodiment 3 | Magnesium sulfate | 3 |
| Embodiment 4 | Magnesium nitrate | 0.5 |
| Embodiment 5 | Magnesium nitrate | 1.5 |
| Embodiment 6 | Magnesium nitrate | 3 |
| Embodiment 7 | Magnesium chloride | 0.5 |
| Embodiment 8 | Magnesium chloride | 1.5 |
| Embodiment 9 | Magnesium chloride | 3 |
The performance index of the prepared plate diamond spar of each embodiment are as shown in table 2, and in plate diamond spar, each composition quality percentage composition is Al
2o
3>=99.1%, SiO
2≤ 0.15%, Fe
2o
3≤ 0.2%, Na
2o≤0.4%.
Table 2
| ? | Volume density g/cm 3 | Apparent porosity % | Water-intake rate % |
| Embodiment 1 | 3.68 | 1.9 | 1.0 |
| Embodiment 2 | 3.75 | 1.6 | 0.8 |
| Embodiment 3 | 3.74 | 1.8 | 0.9 |
| Embodiment 4 | 3.68 | 1.8 | 0.9 |
| Embodiment 5 | 3.74 | 1.6 | 0.8 |
| Embodiment 6 | 3.75 | 1.7 | 0.8 |
| Embodiment 7 | 3.68 | 1.9 | 0.8 |
| Embodiment 8 | 3.73 | 1.7 | 0.8 |
| Embodiment 9 | 3.72 | 1.6 | 0.8 |
Can be obtained the volume density>=3.68g/cm of the plate diamond spar that the inventive method prepares by table 2
3, apparent porosity≤2.0%, can meet the demand for the higher use occasion of plate diamond spar performance requriements such as slide brick.
Claims (8)
1. a preparation method for the plate diamond spar that volume density is high, is characterized in that, comprises the following steps: by water-soluble the one in magnesium nitrate, magnesium chloride or magnesium sulfate, obtain balling-up liquid, adopt this balling-up liquid to carry out γ-Al
2o
3the balling-up of fine powder, gained ball material drying, calcining, cooling forming successively, obtains the described high plate diamond spar of volume density.
2. the preparation method of the plate diamond spar that volume density as claimed in claim 1 is high, is characterized in that, described γ-Al
2o
3in fine powder, more than 95% powder particle size of massfraction is-325 orders.
3. the preparation method of the plate diamond spar that volume density as claimed in claim 1 is high, is characterized in that, in described balling-up liquid, the mass ratio of solute and water is 0.5～3:1, and described solute is the one in magnesium nitrate, magnesium chloride or magnesium sulfate.
4. the preparation method of the plate diamond spar that volume density as claimed in claim 1 is high, is characterized in that, described γ-Al
2o
3the balling-up of fine powder comprises a balling-up and the secondary balling-up carried out successively, the ball material particle diameter that a balling-up obtains is 8～12mm, the ball material particle diameter that secondary balling-up obtains is 25～35mm, in whole balling-up process, apply continuously balling-up liquid, the mass ratio of the quality of balling-up liquid used and ball material is 16～25:100.
5. the preparation method of the plate diamond spar that volume density as claimed in claim 1 is high, it is characterized in that, described being dried comprises primary drying and the redrying of carrying out successively, and the temperature of primary drying is 150～200 DEG C, residual water-content <5% in ball material after primary drying; The temperature of redrying is 450～650 DEG C, residual water-content 1% in ball material after redrying.
6. the preparation method of the plate diamond spar that volume density as claimed in claim 1 is high, is characterized in that, the temperature of described calcining is 1800～2000 DEG C.
7. the preparation method of the plate diamond spar that volume density as claimed in claim 1 is high, is characterized in that, the time of described calcining is 1～3h.
8. the preparation method of the plate diamond spar that volume density as described in as arbitrary in claim 1～7 is high, is characterized in that described γ-Al
2o
3fine powder adopts industrial γ-Al
2o
3ball milling obtains, described industrial γ-Al
2o
3in the weight percentage of each composition be respectively Al
2o
3>=98.5%, SiO
2≤ 0.04%, CaO≤0.1%, Fe
2o
3≤ 0.2%, Na
2o≤0.4%.
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Cited By (5)
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| CN106631072A (en) * | 2016-12-29 | 2017-05-10 | 浙江自立新材料股份有限公司 | Gradient material for castable and preparation method thereof |
| CN108059447A (en) * | 2018-01-08 | 2018-05-22 | 浙江自立新材料股份有限公司 | A kind of big crystallization sintering plate corundum and preparation method thereof |
| WO2018121292A1 (en) * | 2016-12-30 | 2018-07-05 | 武汉科技大学 | Nanoporous light-weight corundum refractory aggregate and preparation method therefor |
| CN111320461A (en) * | 2020-03-02 | 2020-06-23 | 新乡学院 | Preparation method of aluminum oxide for tabular corundum |
| CN116283315A (en) * | 2022-12-30 | 2023-06-23 | 马鞍山利尔开元新材料有限公司 | Carbon-free inorganic pressed spinel sliding plate brick and preparation method thereof |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106631072A (en) * | 2016-12-29 | 2017-05-10 | 浙江自立新材料股份有限公司 | Gradient material for castable and preparation method thereof |
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| CN108059447A (en) * | 2018-01-08 | 2018-05-22 | 浙江自立新材料股份有限公司 | A kind of big crystallization sintering plate corundum and preparation method thereof |
| CN111320461A (en) * | 2020-03-02 | 2020-06-23 | 新乡学院 | Preparation method of aluminum oxide for tabular corundum |
| CN111320461B (en) * | 2020-03-02 | 2022-03-15 | 新乡学院 | Method for preparing plate-shaped corundum |
| CN116283315A (en) * | 2022-12-30 | 2023-06-23 | 马鞍山利尔开元新材料有限公司 | Carbon-free inorganic pressed spinel sliding plate brick and preparation method thereof |
| CN116283315B (en) * | 2022-12-30 | 2023-12-19 | 马鞍山利尔开元新材料有限公司 | Carbon-free inorganic pressed spinel sliding plate brick and preparation method thereof |
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Address after: 312369 Shangyu, Shaoxing, Hangzhou Bay Industrial Park, No., No. three East Road, No. 6 Patentee after: Zhejiang self-reliance new materials Limited by Share Ltd Address before: 312369 Shangyu, Shaoxing, Hangzhou Bay Industrial Park, No., No. three East Road, No. 6 Patentee before: ZHEJIANG ZILI ALUMINA MATERIAL TECHNOLOGY CO., LTD. |
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Application publication date: 20141001 Assignee: Zhejiang Zili High Temperature Technology Co.,Ltd. Assignor: ZHEJIANG ZILI ADVANCED MATERIALS Co.,Ltd. Contract record no.: X2021330000207 Denomination of invention: A preparation method of plate corundum with high bulk density Granted publication date: 20160113 License type: Common License Record date: 20210831 Application publication date: 20141001 Assignee: Shaoxing Hongyi New Material Co.,Ltd. Assignor: ZHEJIANG ZILI ADVANCED MATERIALS Co.,Ltd. Contract record no.: X2021330000208 Denomination of invention: A preparation method of plate corundum with high bulk density Granted publication date: 20160113 License type: Common License Record date: 20210831 |
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