Title of Invention	A FIRED, BASIC, REFRACTORY, INDUSTRAL CERAMIC SHAPED BODY AND PROCESS FOR PRODUCING THE SAME.
Abstract	The invention relates to a fired, basic, refractory, industrial ceramic shaped body comprising at least one basic resistor component and an elasticizer component, wherein the elasticizer component is a calcium aluminate having the abbreviated formula CA6. The invention additionally relates to a process for producing the shaped body and to its use.

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A Fired, Basic, Refractory, Industrial Ceramic Shaped Body And Process for Producing The Same The invention relates to a fired, basic, refractory, industrial ceramic, elasticized shaped body based on at least one resistor component such as magnesia and doloma. In addition, the invention relates to a process for producing the shaped body and to its use. Shaped bodies of the generic type are used as refractory lining, in particular in high-temperature processes involving attack by basic slag, e.g. in furnaces, tanks or vessels in the cement, lime, dolomite, magnesite, steel and nonferrous metals industries and also in the glass industry. Although a shaped body composed of a resistor component (hereinafter also referred to simple as resistor) such as MgO or CaO/MgO (doloma) has a high fire resistance and good chemical resistance, it is generally brittle because it has a relatively high modulus of elasticity (E) and an unfavorable shear modulus (G) . This has an adverse effect on, in particular, the dissipation of thermal stresses, the mechanical stressability and the thermal shock resistance (TSR). It is therefore desirable to set low elastic moduli because these are responsible for the thermomechanical durability. To increase the elasticity or to reduce the elastic moduli, it is known that it is possible to add an elasticizer component (hereinafter also referred to simply as elasticizer) to a mix for producing a shaped body or to add raw materials which generate the elasticizer in the mix during ceramic firing. For example, magnesia-chromite bricks or magnesia-spinel bricks which display usable shear moduli in the range from 8 to 12 GPa (gigapascal) are produced using chromium ores or synthetic spinel. Refractory bricks containing molten hercynite or molten zirconium oxide as elasticizer have a low elasticity but are ductile. The shear moduli are from about 15 to 20 GPa and therefore relatively high. These known elasticized, basic, refractory shaped bodies are evaluated, in particular, in respect of elasticity, desired deposit formation in a rotary tube furnace, redox resistance, alkali resistance, hydration resistance and disposability, with each of these known shaped bodies having, in terms of these properties, advantages and disadvantages, which can be seen from the following table: Table 1: Qualitative properties of known shaped bodies Magnesia-spinel bricks and magnesia-zirconia bricks form a stable deposit in a rotary tube furnace only with difficulty; they consequently have only limited usability in, for example, the sintering zone of a rotary tube furnace for cement. Although magnesia-hercynite bricks display good deposit formation (cf. Variation of Physical and Chemical Parameters as a Tool for the Development of Basic Refractory Bricks; Klischat, Hans-Jurgen, Dr.; Weibel, Guido - REFRATECHNIK GmbH, Germany in Unified International Technical Conference on Refractories, PROCEEDINGS, 6th Biennial Worldwide Congress in conjunction with the 42nd International Colloquium on Refractories, Refractories 2000, BERLIN - Germany 6- 9 September 1999, 50 Years German Refractory Association; pages 204-207), they have a poor redox resistance and alkali resistance. The same applies to magnesia-chromite bricks which are additionally known to create disposal problems. Dolomite bricks containing no elasticizer do ensure very good deposit formation but are neither sufficiently alkali resistant nor sufficiently hydration resistant. It is an object of the invention to provide a basic, elasticized, refractory shaped body which combines high fire resistance and good chemical resistance with, in particular, good elasticity and good deposit formation capability, and good redox, alkali and hydration resistance and can be disposed of without problems. This object is achieved by a fired, basic, refractory, industrial ceramic shaped body comprising at least one basic resistor component and an elasticizer component, characterized in that the elasticizer component is a calcium aluminate having a CaO/Al2O3 ratio of from 0.14 to 0.2. Advantageous embodiments of the invention are defined in the subordinate claims and the other claims. According to the invention, sintered magnesia and/or fused magnesia or sintered doloma and/or fused doloma, selected from among the numerous known resistors, is/are used as basic resistor. Calcium aluminate having a CaO/Al2O3 ratio of from 0.14 to 0.2, in particular of the chemical composition CaAl12O19 having the oxide formula CaO-6Al2O3 or the abbreviated formula CA6, has been found as elasticizer. Calcium hexaaluminate has the chemical formula CaAl12O19 or the mineral name "hibonite" and the oxide formula CaO-6Al2O3 or the abbreviated formula CA6. The A12O3 of the CA6 obviously does not react with the alkali metal and calcium compounds, e.g. in the rotary tube furnace for cement, because it is already saturated with CaO. This results in a very good corrosion resistance. The CaO in the CA6, which is also the main constituent of the cement clinker material, probably ensures very effective deposit formation in the rotary tube furnace, which cannot be achieved even with the deposit-forming, known, elasticized, refractory shaped bodies such as magnesia-hercynite bricks or magnesia-chromite bricks. CA6 is not an unknown in refractory materials. A refractory shaped body whose mineral oxidic component is formed by a mineral phase mixture of ?-Al2O3, P-A12O3, CA6 and CA2 is known from DE 199 36 292 C2. The mineral phase mixture is said to increase the corrosion resistance of the shaped bodies. CA6 does not play an elasticizing role here. It is preferred that the shaped body comprises from 60 to 99.5% by mass of resistor component and from 0.5 to 40% by mass of elasticizer component. Preferably, at least one further elasticizer known per se is present. Further, it is preferred that the shaped body has an overall density of from 2.5 to 3.2 g/cm3. Preferably, the shaped body has a porosity of from 12 to 25% by volume, in particular from 14 to 23% by volume. It is preferred that the shaped body has a cold compressive strength above 35 MPa, in particular above 45 MPa, and a cold flexural strength above 2 MPa. Preferably, the shaped body has a modulus of elasticity of from 14 to 35 GPa, in particular from 15 to 32 GPa, and a shear modulus of from 6 to 15 GPa, in particular from 7 to 14 GPa. It is further preferred that the shaped body has a thermal shock resistance of >80. The shaped body according to the present invention is produced by a process which comprises mixing at least one resistor component with at least one CA6 elasticizer component and admixing the mixture with a binder and mixing it to form a shapeable composition, subsequently shaping the composition to produce bodies and drying the shaped bodies and then firing the bodies at high temperatures to sinter them. Preferably, drying is carried out at temperatures of from 100 to 120°C. It is preferred that sintering is carried out at temperatures of from 1400 to 1700°C, in particular from 1550 to 1650°C. It is further preferred that from 60 to 99.5% by mass of resistor component and from 0.5 to 40% by mass of elasticizer component are used. Also it is preferred that at least one pre-- synthesized elasticizer component is used. Preferably, a granulated mixture for the elasticizer component obtained by mixing appropriate raw materials is mixed with the resistor component and the elasticizer component is generated during firing. The invention is illustrated below with the aid of an example: Magnesia having a maximum particle size of 4 mm and a particle size distribution corresponding to a typical Fuller curve and the mineral calcium hexaaluminate having a particle size range from 0.5 to 4 mm were mixed, admixed with a required amount of lignin sulfonate as binder, shaped to form bricks and pressed at a specific pressing pressure of 130 MPa. After drying at 110°C, the bricks were fired at a sintering temperature of 1600°C in a tunnel kiln. The achieved properties of the fired bricks as a function of the amount of calcium hexaaluminate added are shown in table 2 below. A magnesia brick fired in the same way was employed as comparison. Table 2: Properties of shaped bodies according to the invention compared to properties of a magnesia brick It can be seen from table 2 that the bricks according to the invention are sufficiently elasticized for use in a rotary tube furnace for cement with its temperature-dynamic conditions. The elastic moduli are within a very good range. The thermal shock resistance (TSR) is excellent. The mechanism which leads to the very good elasticization of the bricks has hitherto not been able to be determined unambiguously. There is presumably microcrack formation between the magnesia matrix and the calcium hexaaluminate during firing of the bricks, caused by the difference in the thermal expansion of these two materials. Table 3 below shows the individual relevant properties of the known shaped bodies of table 1 and those of the shaped bodies according to the invention. Table 3: Qualitative properties of known shaped bodies compared to a shaped body according to the invention Table 3 shows that all the types of brick known hitherto have significant disadvantages in terms of the application-relevant properties. In contrast, the magnesia-CA6 bricks of the invention have exclusively good properties, as have hitherto not been known in their use-relevant combination. Shaped bodies according to the invention can be used advantageously wherever severe temperature changes occur and wherever mechanical and thermomechanical stresses occur. These are, for example, sintering and transition zones of rotary tube furnaces in the brick and earth industry, in particular the cement, lime, dolomite and magnesite industries, ferrous and nonferrous metals industry and also melting and handling vessels in the iron or steel industry and the nonferrous metals industry. A shaped body according to the invention displays excellent use performance in respect of hydration, alkali, redox and corrosion resistance combined with good deposit formation tendency. It is thus also superior to the known products after use because of unproblematical disposal possibilities. The elasticization of the basic shaped bodies according to the invention can be achieved using not only pure calcium hexaaluminate, but it is also possible for secondary phases, e.g. SiO2 and/or TiO2 and/or Fe2O3 and/or MgO, to be present in amounts of up to 10% by mass in the calcium hexaaluminate. Furthermore, the calcium hexaaluminate also has the action described when up to 58% by mass of the A12O3 has been replaced by Fe2O3 or when Ca2+ has been partly replaced by Ba2+ or Sr2+, as indicated in "Trojer, F.: Die oxydischen Kristallphasen der anorganischen Industrieprodukte", E. Schweizerbart"sche Verlagsbuchhandlung, Stuttgart 1963, page 272. WE CLAIM : 1. A fired, basic, refractory, industrial ceramic shaped body comprising at least one basic resistor component and an elasticizer component, characterized in that the elasticizer component is a calcium aluminate having a CaO/AI2O3 ratio of from 0.14 to 0.2. 2. The shaped body as claimed in claim 1, wherein the elasticizer component has the chemical formula CaAl12O19 or the oxide formula CaO.6AI2O3 or the abbreviated formula CA6. 3. The shaped body as claimed in claim 1 and/or 2, wherein the elasticizer component contains up to 10% by mass of secondary phases. 4. The shaped body as claimed in claim 3, wherein the elasticizer component contains SiO2 and/or TiO2 and/or Fe2O3 and/or MgO as secondary phases. 5. The shaped body as claimed in any preceding claim, wherein upto 58% by mass of AI2O3 has been replaced by Fe2O3 in the elasticizer component. 6. The shaped body as claimed in any preceding claim, wherein Ca2+ has been partly replaced by Ba2+ and/or Sr2+ in the elasticizer component. 7. The shaped body as claimed in any preceding claim, wherein the resistor component is sintered MgO and/or fused magnesia and/or sintered doloma and./or fused doloma. 8. The shaped body as claimed in any preceding claim, wherein the shaped body comprises from 60 to 99.5% by mass of resistor component and from 0.5 to 40% by mass of elasticizer component. 9. The shaped body as claimed in any preceding claim, wherein at least one further elasticizer known per se is present. 10. The shaped body as claimed in any preceding claim, having an overall density of from 2.5 to 3.2 g/cm3. 11. The shaped body as claimed in any preceding claim, having a porosity of from 12 to 25% by volume, in particular from 14 to 23% by volume. 12. The shaped body as claimed in any preceding claim, having a cold compressive strength above 35 MPa, in particular above 45 MPa, and a cold flexural strength above 2 MPa. 13. The shaped body as claimed in any preceding claim, having a modulus of elasticity of from 14 to 35 GPa, in particular from 15 to 32 GPa, and a shear modulus of from 6 to 15 GPa, in particular from 7 to 14 GPa. 14. The shaped body as claimed in any preceding claim, having a thermal shock resistance of >80. 15. The process for producing a shaped body as claimed in claims 1 to 14, which comprises mixing at least one resistor component with at least one CaO.6AI2O3 elasticizer component and admixing the mixture with a binder and mixing it to form a shapeable composition, subsequently shaping the composition to produce bodies and drying the shaped bodies and then firing the bodies at high temperatures to sinter them. 16. The process as claimed in claim 15, wherein lignin sulfonate is used as binder. 17. The process as claimed in claim 15 and/or 16, wherein the resistor component used has a maximum particle size of 4 mm and a particle size distribution corresponding to a Fuller curve. 18. The process as claimed in claims 15 to 17, wherein the elasticizer component used has a particle size range from 0.5 to 4 mm. 19. The process as claimed in claims 15 to 18, wherein drying is carried out at temperatures of from 100 to 120° C. 20. The process as claimed in any claims 15 to 19, wherein sintering is carried out at temperatures of from 1400 to 1700° C, in particular from 1550 to 1650° C. 21. The process as claimed in claims 15 to 20, wherein from 60 to 99.5% by mass of resistor component and from 0.5 to 40% by mass of elasticizer component are used. 22. The process as claimed in claims 15 to 21, wherein at least one presynthesized elasticizer component is used. 23. The process as claimed in claims 15 to 22, wherein a granulated mixture for the elasticizer component obtained by mixing appropriate raw materials is mixed with the resistor component and the elasticizer component is generated during firing. 24. The process as claimed in claims 15 to 23, wherein firing is carried out so that microcrack formation between the resistor matrix and the elasticizer component occurs. 25. A rotary tube furnace wherein the masonry lining comprises a fired, basic, refractory, industrial ceramic shaped body as claimed in claims 1 to 14 and produced by the process as claimed in claims 15 to 24. 26. The rotary tube furnace as claimed in claim 25, wherein the masonry lining in the sintering zone comprises said fired, basic, refractory, industrial ceramic shaped bodies. 27. The rotary tube furnace as claimed in claims 25 and/or 26, wherein the masonry lining in the lower transition zone comprises said fired, basic, refractory, industrial ceramic shaped bodies. 28. The rotary tube furnace as claimed in claims 25 to 27, wherein said furnace is a rotary tube furnace for cement. The invention relates to a fired, basic, refractory, industrial ceramic shaped body comprising at least one basic resistor component and an elasticizer component, wherein the elasticizer component is a calcium aluminate having the abbreviated formula CA6. The invention additionally relates to a process for producing the shaped body and to its use.

Documents:

1080-KOLNP-2005-(03-01-2012)-FORM-27.pdf

1080-KOLNP-2005-CORRESPONDENCE 1.1.pdf

1080-KOLNP-2005-CORRESPONDENCE.pdf

1080-KOLNP-2005-FORM 27 1.1.pdf

1080-KOLNP-2005-FORM 27.pdf

1080-kolnp-2005-granted-abstract.pdf

1080-kolnp-2005-granted-assignment.pdf

1080-kolnp-2005-granted-claims.pdf

1080-kolnp-2005-granted-correspondence.pdf

1080-kolnp-2005-granted-description (complete).pdf

1080-kolnp-2005-granted-examination report.pdf

1080-kolnp-2005-granted-form 1.pdf

1080-kolnp-2005-granted-form 18.pdf

1080-kolnp-2005-granted-form 3.pdf

1080-kolnp-2005-granted-form 5.pdf

1080-kolnp-2005-granted-gpa.pdf

1080-kolnp-2005-granted-letter patent.pdf

1080-kolnp-2005-granted-reply to examination report.pdf

1080-kolnp-2005-granted-specification.pdf

1080-kolnp-2005-granted-translated copy of priority document.pdf