CN103172396A - Mg-Ca-Zr-Ti brick for cement kiln and preparation method thereof - Google Patents
Mg-Ca-Zr-Ti brick for cement kiln and preparation method thereof Download PDFInfo
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- CN103172396A CN103172396A CN2013101257634A CN201310125763A CN103172396A CN 103172396 A CN103172396 A CN 103172396A CN 2013101257634 A CN2013101257634 A CN 2013101257634A CN 201310125763 A CN201310125763 A CN 201310125763A CN 103172396 A CN103172396 A CN 103172396A
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- cement kiln
- magnesium calcium
- cao
- titanium dioxide
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Abstract
The invention relates to the field of Mg-Ca-containing refractory materials, in particular to a Mg-Ca-Zr-Ti brick for a cement kiln and a preparation method of the brick; the Mg-Ca-Zr-Ti brick for the cement kiln is characterized by comprising the following raw materials by weight percent: 95-99% of synthesized Mg-Ca sand, 1-5% of electric smelting stable zirconium oxide, 1-3% of titanium dioxide and bonding agent, wherein the weight of the bonding agent accounts for 2-5% of the total weight of the three raw materials, and paraffin is adopted as the bonding agent. The preparation method of the brick has the technological process steps of: preparing the raw materials, blending, mixing, drying, molding by pressing and sintering and is characterized in that the sintering temperature is between 1520 DEG C and 1570 DEG C. Compared with the prior art, on the premise that the advantages of a magnesite-dolomite brick are maintained, the Mg-Ca-Zr-Ti brick effectively overcomes the disadvantages of the conventional magnesite-dolomite brick, such as thermal shock resistance and high hydration rate; and the Mg-Ca-Zr-Ti brick has the characteristics of good thermal shock resistance and good hydration resistance, and can be used for replacing a magnesite-chrome brick used for a cement kiln burning zone, thus realizing non-chromium characteristic of the refractory brick for the cement kiln.
Description
Technical field
The present invention relates to contain magnesium calcium class fire resisting material field, relate in particular to a kind of cement kiln magnesium calcium zirconium titanium brick and production method thereof.
Background technology
At present, the cement kiln clinkering zone uses magnesia chrome brick as the main body kiln lining, and this brick has following advantage: 1. good extension kliner coating is arranged, and 2. 3. good heat-shock resistance and low thermal conductivity have good resistance to fouling to cement clinker.When but magnesia chrome brick uses in cement kiln, under alkalescence and oxidizing atmosphere, the Cr in magnesia chrome brick
3+Be easy to be converted into the extremely strong Cr of oxidation capacity
6+, generate R
2CrO
4Deng severe toxicity and carcinogenic hexavalent chromium compound, condense upon in the kiln brick.The kiln brick can cause serious pollution to environment with chromic residual brick after removing.The high valence chrome hydrochlorate can cause skin lesion, respiratory inflammation and mucosal ulcer, and even more serious sexavalent chrome can also cause skin carcinoma and lung cancer.Therefore, strict regulation has all been done to chromic content by many countries, and Japanese tap water law regulation: in tap water, content of 6-valence Cr ions is below 0.05mg/L.Industrial waste facture regulation: a) by the inorganic pollution inspection liquid that produces in trade waste or factory, sexavalent chrome is below 0.5mg/L; B) the pollution inspection liquid that is produced by trade waste or factory, sexavalent chrome is below 1.5mg/L.Britain regulation: refractory materials manufacturing, when transporting, build by laying bricks or stones, tearing open stove and processing (cut, bore, grind), ultimate value 0.02 ~ 0.05mg/m that sexavalent chrome exposes
3China is same to the Cr in Environmental Quality of Earth Surface Water in National Environmental quality standard GB3838-88
6+Made corresponding regulation (seeing Table 1), the Cr in the visible residual brick of magnesium chromium
6+Work can cause severe contamination to environment.
Table 1
Use the chromium pollution problem of basic refractory in order to solve cement kiln, the chromium-free brick that domestic and international cement kiln clinkering zone is used has Mg-Al spinel brick, mafic spinel brick, konite brick and magnesium zirconia block.
At present, Mg-Al spinel brick has been successfully applied to the transitional zone of cement kiln, is restricted but use at the cement kiln clinkering zone because itself and kliner coating adhesion property are poor.
For improving the kliner coating adhesion property of Mg-Al spinel brick, carried out following concrete improvement measure both at home and abroad:
1. reduce the Al in Mg-Al spinel brick
2O
3Content, the CaO that can reduce like this in itself and cement clinker generates the amount of eutectic, thus it is good to hang the kliner coating performance.But reduce Al
2O
3Content after, can produce certain impact to the performances such as heat-shock resistance of Mg-Al spinel brick, thereby affect its use properties; 2. add ZrO in Mg-Al spinel brick
2, ZrO
2Be far longer than spinel with the reactive behavior of CaO composition in cement clinker, its product is CaZrO
3High melting compound, therefore, ZrO
2Add the reaction that suppressed spinel and suffered chemical erosion.In addition, CaZrO
3Have disactivation on chemical property with cement clinker, both can coexist.If but to form stable kliner coating, and need add a large amount of zirconium whites, but the zirconium white price is more expensive, cause this series refractory material to be promoted very difficult; 3. add Fe
2O
3, add appropriate Fe
2O
3Can improve the extension kliner coating performance of Mg-Al spinel brick, still, this spinel brick is only applicable to because kiln atmosphere is unstable, Fe will occur in kiln atmosphere is stable, load is not high situation
3+→ Fe
2+Transformation, and follow volumetric expansion and produce thermal stresses, cause refractory materials to damage too early.
Mafic spinel brick is that domestic now to be applied to the cement kiln clinkering zone maximum, but its high thermal resistance, resistance to fouling and anti-oxidant reducing power are not good, when cement kiln uses alternative fuel, can cause kiln temperature to raise, and atmosphere is also unstable, this moment with this brick as the main body kiln lining and be not suitable for.
The magnesium zirconia refractory has good resistance to fouling, heat-shock resistance.Magnesium calcium zirconia refractory also has good kliner coating tack, but this class refractory materials need add the ZrO of a large amount of costlinesses
2, cause the use of this series refractory material to be restricted.
Rhombspar is that brick contains a large amount of CaO, can with cement clinker in SiO
2Reaction generates C
3S, C
2The mineral such as S, thus extension kliner coating performance is good.In addition, the rhombspar raw material resources are abundant and be dirt cheap, and therefore, rhombspar is that brick is widely used on the clinkering zone of America and Europe's cement kiln, and wherein, the U.S. has 87% the rotating clinkering zone of cement to use this product.But the characteristics of dolomite brick are that heat-shock resistance and hydration resistance are poor.The CaO content of dolomite brick is high, because at high temperature creep of CaO is large, therefore, can produce larger contraction after the reheating of dolomite brick, and when rotary kiln was cooling, it was loosening because shrinking the excessive brick that makes.Reduce the content of CaO, the content that increases MgO can reduce after contraction.In addition, because the aquation of MgO-CaO sand is mainly the aquation of CaO, therefore, the content that increases MgO can improve the hydration resistance of MgO-CaO brick.Studies show that, by the synthetic konite sand of dolomite sand and magnesia, the result of use that MgO content is increased to 60% ~ 70% rich konite is much better than dolomite brick.
Summary of the invention
The purpose of this invention is to provide a kind of cement kiln with magnesium calcium zirconium titanium brick and production method thereof, overcome the deficiencies in the prior art, solve that traditional konite brick heat-shock resistance is poor, the problem of easy aquation.
For solving the problems of the technologies described above, technical scheme of the present invention is:
A kind of cement kiln magnesium calcium zirconium titanium brick is comprised of following raw materials by weight:
Synthetic magnesia-calcium clinker 95～99%;
Electric smelting stabilizing zirconia 1～5%;
Wedding agent accounts for 2～5% of above-mentioned three kinds of raw material summations.
The specification of quality of described synthetic magnesia-calcium clinker is: MgO 〉=40%, CaO 〉=20%, Σ (Fe
2O
3+ Al
2O
3+ SiO
2)≤3 %, igloss≤0.5%, volume density 〉=3.17 gcm
-3, granularity≤5 mm.
The specification of quality of described electric smelting stabilizing zirconia is ZrO
2〉=95%, Al
2O
3≤ 0.40%, CaO≤5%, granularity 1～3mm, volume density 〉=5.70 gcm
-3
Described titanium dioxide is industrial Rutile type Titanium Dioxide, requires TiO
2〉=95%, rutile crystal type structure 〉=99%, granularity≤0.045mm.
Described wedding agent is paraffin, its water content≤0.4%.
A kind of cement kiln production method of magnesium calcium zirconium titanium brick, its technical process comprises raw material preparation, batching, batch mixing, the material that dries in the air, compression moulding and firing process, its firing range is at 1520～1570 ℃.
The present invention is by adding ZrO
2Improve the anti-thermal shock stability of konite, it improves mechanism three kinds of viewpoints: 1. ZrO
2With CaO reaction CaZrO
3, it is " softness " relatively, can play the effect of buffering stress; 2. ZrO
2Change Tetragonal into by monoclinic phase, toughening effect is played in its phase transformation; 3. CaZrO
3Because thermal expansivity is different, and produce tiny crack with rhombspar, thereby absorb thermal stresses and organize the expansion of crackle.In a word, add ZrO
2Really can improve the anti-thermal shock stability of konite.
Add TiO
2Can effectively prevent the aquation of konite series refractory material.At TiO
2Add-on situation seldom under MgO and TiO
2Generate 2MgOTiO
2, CaO and TiO
2Generate 3CaO2 TiO
2As shown in Figure 1, can find out 2MgOTiO
2Free energy greater than 3CaO2 TiO
2, this just illustrates and add TiO in magnesia-calcium brick
2, preferential and CaO reacts and mainly generates 3CaO2 TiO
2, rather than 2MgOTiO
2, this has just explained TiO
2Prevent the reason of aquation.TiO
2Generated fusing point than MgO and the low 3CaO2TiO of CaO with CaO
2, make system a small amount of liquid phase acceleration of sintering occur at a lower temperature.The 3CaO2TiO that generates
2Be present in mutually in the crystal boundary of principal crystalline phase, for atomic diffusion provides the fast transferring approach, promoted sintering.In addition, 3CaO2TiO
2Generation, cause free CaO to exist in discontinuous mode, be conducive to improve the hydration resistance of magnesia-calcium brick, so add TiO
2Good preventing hydration additive, short agglutinant.The present invention is by adding titanium dioxide to introduce TiO
2Solve the problem of easy aquation
Compared with prior art, the invention has the beneficial effects as follows: under the prerequisite of the plurality of advantages that keeps konite brick, solved effectively that traditional konite brick heat-shock resistance is poor, the problem of easy aquation, the present invention has that physical strength is high, refractoriness is high, corrosion resistance is good, the kliner coating adhesive ability is strong, good thermal shock, the characteristics that hydration resistance is good, can replace cement kiln clinkering zone magnesia chrome brick, realize the cement kiln Trend of Chrome-free of refractory brick.
Description of drawings
Fig. 1 is 2MgOTiO under differing temps
2With 3CaO2 TiO
2The free energy change curve.
Embodiment
The invention will be further described below in conjunction with specific embodiment:
A kind of cement kiln of the present invention magnesium calcium zirconium titanium brick is comprised of following raw materials by weight: synthetic magnesia-calcium clinker 95～99%, electric smelting stabilizing zirconia 1～5%, titanium dioxide 1～3%, and above-mentioned three kinds of raw material summations are 100%; Its water content of wedding agent paraffin≤0.4% accounts for 2～5% of above-mentioned three kinds of raw material summations.A kind of cement kiln of the present invention production method of magnesium calcium zirconium titanium brick, its technical process comprises raw material preparation, batching, batch mixing, the material that dries in the air, compression moulding and firing process, it is characterized in that, its firing range is at 1520～1570 ℃.
Wherein, the specification of quality of synthetic magnesia-calcium clinker is: MgO 〉=40%, CaO 〉=20%, Σ (Fe
2O
3+ Al
2O
3+ SiO
2)≤3 %, igloss≤0.5%, volume density 〉=3.17 gcm
-3, granularity≤5 mm.The specification of quality of electric smelting stabilizing zirconia is ZrO
2〉=95%, Al
2O
3≤ 0.40%, CaO≤5%, granularity 1～3mm, volume density 〉=5.70 gcm
-3Titanium dioxide is industrial Rutile type Titanium Dioxide, requires TiO
2〉=95%, rutile crystal type structure 〉=99%, granularity≤0.045mm.
Magnesium calcium zirconium titanium brick composition (wt) after making is CaO 18～44%, ZrO
20.9～4.5%, TiO
21～3%, other trace ingredients sum of MgO+ is 45～80%.
The present invention reacts the water resistant ability of this refractory materials by detecting the rate of body weight gain of refractory materials under certain temperature, certain pressure condition.The TiO of different content
2Impact on magnesium calcium zirconium Ti refractory material water resistant ability sees Table 2.
Table 2
Embodiment 1:
Get by weight percentage calcium magnesia sand 98%, electric smelting stabilizing zirconia 1.5%, titanium dioxide 0.5% preparation brickmaking material, this material is through coordinating, add 3.3% paraffin to carry out as wedding agent making refractory materials after mixing, the material that dries in the air, moulding and 1560 ℃ burn till.
After testing, the performance of refractory materials is: volume density is 2.99 gcm
-3, apparent porosity 14.8%, cold crushing strength 58MPa, high temperature break resistant intensity 3.6 MPa, 950 ℃ of air blast cooling number of times 100 times, after hydration test, rate of body weight gain 1.7%.
Embodiment 2:
Get by weight percentage calcium magnesia sand 97%, electric smelting stabilizing zirconia 1.5%, titanium dioxide 1.5% preparation brickmaking material, this material is through coordinating, add 3.5% paraffin to carry out as wedding agent making refractory materials after mixing, the material that dries in the air, moulding and 1520 ℃ burn till.
After testing, the performance of refractory materials is: volume density is 3.08 gcm
-3, apparent porosity 12.5%, cold crushing strength 72MPa, high temperature break resistant intensity 4.5 MPa, 950 ℃ of air blast cooling number of times 100 times, after hydration test, rate of body weight gain 1.3%.
Embodiment 3:
Get by weight percentage calcium magnesia sand 98.5%, electric smelting stabilizing zirconia 1%, titanium dioxide 0.5% preparation brickmaking material, this material is through coordinating, add 3.3% paraffin to carry out as wedding agent making refractory materials after mixing, the material that dries in the air, moulding and 1570 ℃ burn till.
After testing, the performance of refractory materials is: volume density is 3.03 gcm
-3, apparent porosity 13.5%, cold crushing strength 65MPa, high temperature break resistant intensity 3.7 MPa, 950 ℃ of air blast cooling number of times 80 times, after hydration test, rate of body weight gain 1.7%.
Embodiment 4:
Get by weight percentage calcium magnesia sand 96.5%, electric smelting stabilizing zirconia 3%, titanium dioxide 0.5% preparation brickmaking material, this material is through coordinating, add 3.3% paraffin to carry out as wedding agent making refractory materials after mixing, the material that dries in the air, moulding and 1560 ℃ burn till.
After testing, the performance of refractory materials is: volume density is 3.01 gcm
-3, apparent porosity 13.9%, cold crushing strength 55MPa, high temperature break resistant intensity 3.4 MPa, 950 ℃ of air blast cooling number of times 110 times, after hydration test, rate of body weight gain 1.7%.
Claims (6)
1. a cement kiln with magnesium calcium zirconium titanium brick, is characterized in that, is comprised of following raw materials by weight:
Synthetic magnesia-calcium clinker 95～99%;
Electric smelting stabilizing zirconia 1～5%;
Titanium dioxide 1～3%, above-mentioned three kinds of raw material summations are 100%;
Wedding agent accounts for 2～5% of above-mentioned three kinds of raw material summations.
2. a kind of cement kiln according to claim 1 with magnesium calcium zirconium titanium brick, is characterized in that, the specification of quality of described synthetic magnesia-calcium clinker is: MgO 〉=40%, CaO 〉=20%, Σ (Fe
2O
3+ Al
2O
3+ SiO
2)≤3 %, igloss≤0.5%, volume density 〉=3.17 gcm
-3, granularity≤5 mm.
3. a kind of cement kiln according to claim 1 with magnesium calcium zirconium titanium brick, is characterized in that, the specification of quality of described electric smelting stabilizing zirconia is ZrO
2〉=95%, Al
2O
3≤ 0.40%, CaO≤5%, granularity 1～3mm, volume density 〉=5.70 gcm
-3
4. a kind of magnesium calcium zirconium titanium brick according to claim 1, is characterized in that, described titanium dioxide is industrial Rutile type Titanium Dioxide, requires TiO
2〉=95%, rutile crystal type structure 〉=99%, granularity≤0.045mm.
5. a kind of cement kiln according to claim 1 with magnesium calcium zirconium titanium brick, is characterized in that, described wedding agent is paraffin, its water content≤0.4%.
6. a kind of cement kiln claimed in claim 1 is with the production method of magnesium calcium zirconium titanium brick, and its technical process comprises raw material preparation, batching, batch mixing, the material that dries in the air, compression moulding and firing process, it is characterized in that, its firing range is at 1520～1570 ℃.
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|---|---|---|---|
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|---|---|---|---|
| CN201310125763.4A CN103172396B (en) | 2013-04-11 | 2013-04-11 | Mg-Ca-Zr-Ti brick for cement kiln and preparation method thereof |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105060900A (en) * | 2015-07-23 | 2015-11-18 | 郑州市科源耐火材料有限公司 | Magnesium zirconium calcium brick for stainless steel smelting kiln |
| CN105693209A (en) * | 2016-01-20 | 2016-06-22 | 广西丛欣实业有限公司 | Sintered brick |
| CN111517759A (en) * | 2020-04-30 | 2020-08-11 | 辽宁科技大学 | Preparation method of high-thermal-shock high-hydration-resistance MgO-CaO sand |
| CN112500135A (en) * | 2021-02-05 | 2021-03-16 | 北京利尔高温材料股份有限公司 | Magnesium-calcium tundish dry working lining material and preparation method thereof |
| CN115417658A (en) * | 2022-08-17 | 2022-12-02 | 辽宁中镁新材料有限公司 | Novel magnesium aluminate spinel brick for cement kiln burning zone and production method thereof |
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| CN1994970A (en) * | 2006-10-24 | 2007-07-11 | 海城市后英经贸集团有限公司 | Magnesia calcium zirconium brick for cement rotary kiln |
| CN102765951A (en) * | 2012-08-02 | 2012-11-07 | 营口青花耐火材料股份有限公司 | Magnesium-calcium-titanium-carbon brick and preparation method thereof |
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2013
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Patent Citations (2)
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| CN1994970A (en) * | 2006-10-24 | 2007-07-11 | 海城市后英经贸集团有限公司 | Magnesia calcium zirconium brick for cement rotary kiln |
| CN102765951A (en) * | 2012-08-02 | 2012-11-07 | 营口青花耐火材料股份有限公司 | Magnesium-calcium-titanium-carbon brick and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105060900A (en) * | 2015-07-23 | 2015-11-18 | 郑州市科源耐火材料有限公司 | Magnesium zirconium calcium brick for stainless steel smelting kiln |
| CN105060900B (en) * | 2015-07-23 | 2017-04-19 | 郑州市科源耐火材料有限公司 | Magnesium zirconium calcium brick for stainless steel smelting kiln |
| CN105693209A (en) * | 2016-01-20 | 2016-06-22 | 广西丛欣实业有限公司 | Sintered brick |
| CN111517759A (en) * | 2020-04-30 | 2020-08-11 | 辽宁科技大学 | Preparation method of high-thermal-shock high-hydration-resistance MgO-CaO sand |
| CN112500135A (en) * | 2021-02-05 | 2021-03-16 | 北京利尔高温材料股份有限公司 | Magnesium-calcium tundish dry working lining material and preparation method thereof |
| CN115417658A (en) * | 2022-08-17 | 2022-12-02 | 辽宁中镁新材料有限公司 | Novel magnesium aluminate spinel brick for cement kiln burning zone and production method thereof |
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