DE4331761C2 - Process for the production of refractory products based on magnesium oxide - Google Patents
Process for the production of refractory products based on magnesium oxideInfo
- Publication number
- DE4331761C2 DE4331761C2 DE4331761A DE4331761A DE4331761C2 DE 4331761 C2 DE4331761 C2 DE 4331761C2 DE 4331761 A DE4331761 A DE 4331761A DE 4331761 A DE4331761 A DE 4331761A DE 4331761 C2 DE4331761 C2 DE 4331761C2
- Authority
- DE
- Germany
- Prior art keywords
- grain
- mass
- aluminum hydroxide
- aluminum
- mgo
- 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 - Fee Related
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/03—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite
- C04B35/04—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite based on magnesium oxide
- C04B35/043—Refractories from grain sized mixtures
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/03—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite
- C04B35/04—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite based on magnesium oxide
- C04B35/043—Refractories from grain sized mixtures
- C04B35/0435—Refractories from grain sized mixtures containing refractory metal compounds other than chromium oxide or chrome ore
Description
Die Erfindung betrifft ein Verfahren zur Herstellung von feuerfesten Erzeugnissen auf der Basis von Magnesiumoxid, aus gehend von einer Sinter- und/oder Schmelzmagnesia- Körnung mit mindestens 95 Masse-% MgO, nach Patent DE 43 19 741.The invention relates to a method for producing refractory products based on magnesium oxide starting from a sintered and / or fused magnesia grain with at least 95% by mass of MgO, according to patent DE 43 19 741.
Gemäß Hauptpatent erfolgt die Herstellung von feuerfesten MgO- Erzeugnissen unter Verwendung einer porösen Aluminiumoxid- Körnung mit einer Größe von mindestens 0,5 mm. Nachteilig ist die Verwendung des kostenintensiven Aluminiumoxides.According to the main patent, the production of refractory MgO Products using a porous alumina Grain with a size of at least 0.5 mm. The disadvantage is the use of the expensive aluminum oxide.
Aus DE-PS 903 437 ist bekannt, einem üblichen Sintermagnesit metallisches Aluminium in gekörnter Form zuzusetzen, um die Raumbeständigkeit von Magnesitsteinen und -massen zu verbes sern. Gleichzeitig verbessert sich die Temperaturwechselbe ständigkeit (nachfolgend TWB), die auf die fortschreitende Spinellbildung durch Oxidation des Aluminiums zurückzuführen ist, wodurch jedoch ein höheres Volumenwachstum hervorgerufen wird und eine stärkere Auflockerung des Gefüges eintritt. Nachteilig ist weiterhin die Verwendung des energieintensiv hergestellten Aluminiums. Außerdem bilden sich aus dem verunreinigten Sintermagnesit mit dem aus Aluminium ent stehenden Al2O3 niedrigschmelzende Phasen, die die Feuer festigkeit des Erzeugnisses herabsetzen.From DE-PS 903 437 it is known to add a conventional sintered magnesite to metallic aluminum in granular form in order to improve the spatial stability of magnesite stones and masses. At the same time, the temperature change resistance (hereinafter TWB) improves, which can be attributed to the progressive formation of spinel through oxidation of the aluminum, but this causes higher volume growth and a stronger loosening of the structure. Another disadvantage is the use of the energy-intensive aluminum. In addition, low-melting phases are formed from the contaminated sintered magnesite with the Al 2 O 3 formed from aluminum, which reduce the fire resistance of the product.
Aus US- PS 48 33 109 ist ein Magnesia-Spinell-Erzeugnis be kannt, das aus mindestens 3 Komponenten (Magnesia, spinell- oder tonerdehaltiges Material und porosierender Zuschlag) besteht und damit eine geringe Wärmeleitfähigkeit aufweist. Die TWB wird dadurch nicht beeinflußt.From US-PS 48 33 109 is a magnesia spinel product be knows that from at least 3 components (magnesia, spinel or alumina material and porous aggregate) exists and thus has a low thermal conductivity. This does not affect the TWB.
Die Verwendung von Aluminiumhydroxid ist nach N.A.L. MANSOUR, Interceram, 1978, S. 49-51 und M.A. SERRV und S.M. NAGA, Silicates industriels, 1987, Nr. 3-4, S. 41-46 bekannt. Jedoch dient das Aluminiumhydroxid ausschließlich zur Herstel lung des Spinells, der in Form unterschiedlicher Körnungen dem Magnesiaversatz zugesetzt wird.The use of aluminum hydroxide is, according to N.A.L. MANSOUR, Interceram, 1978, pp. 49-51 and M.A. SERRV and S.M. NAGA, Silicates industriels, 1987, No. 3-4, pp. 41-46. However, the aluminum hydroxide is used only for manufacturing the spinel, which in the form of different grain sizes Magnesia replacement is added.
Technisch verfügbares Aluminiumhydroxid ist ein feinkörniges Pulver mit einem maximalen Korndurchmesser von kleiner 80 µm (A. PETZOLD, J. ULBRICHT, Aluminiumoxid, Deutscher Verlag für Grundstoffindustrie, 1991, S. 38). Wird dieses Pulver in ein Gemisch von Magnesiumoxid-Körnungen eingeführt, so entsteht nach dem Brand eine spinellhaltige Bindematrix mit einer we sentlich kleineren Wärmedehnung als das Magnesiakorn. Dies führt zu einem Spannungszustand im Gefüge, der eine der Haupt ursachen für eine niedrige mechanische Festigkeit ist.Technically available aluminum hydroxide is a fine grain Powder with a maximum grain diameter of less than 80 µm (A. PETZOLD, J. ULBRICHT, aluminum oxide, German publisher for Grundstoffindustrie, 1991, p. 38). This powder will turn into one Mixture of magnesium oxide grains introduced, so arises after the fire a spinel-containing binding matrix with a white considerably less thermal expansion than the magnesia grain. This leads to a state of tension in the structure, which is one of the main cause of low mechanical strength.
Die Aufgabe der Erfindung besteht darin, das Erfindungsmerkmal des Hauptpatentes weiter auszubilden, um kostengünstiger feuerfeste Erzeugnisse hoher TWB auf der Basis von MgO herzu stellen.The object of the invention is the inventive feature of the main patent to continue training to be more cost-effective refractory products of high TWB based on MgO put.
Erfindungsgemäß wird die Aufgabe mit den Merkmalen des Haupt anspruches gelöst.According to the invention the task with the features of the main claim solved.
Die Merkmale der Unteransprüche gestalten die Erfindung vor teilhaft aus.The features of the subclaims form the invention partial.
Das erfindungsgemäße Verfahren, bei dem das Aluminiumhydroxid in einer definierten Körnung eingesetzt wird, grenzt sich deutlich von der bisher üblichen Verwendung des Aluminium hydroxides für die Spinell-Synthese ab.The inventive method in which the aluminum hydroxide is used in a defined grain size clearly from the usual use of aluminum hydroxides for spinel synthesis.
Auch ist das erfindungsgemäße Verfahren nicht vergleichbar mit dem Zusatz von metallischem Aluminium gemäß DE-PS 903 437.The method according to the invention is also not comparable to the addition of metallic aluminum according to DE-PS 903 437.
Bei Verwendung grober aluminiumhydroxidhaltiger Körnung, bestehend aus Aluminiumhydroxid oder einem Gemisch aus Aluminiumhydroxid und Aluminiumoxid, wird erfindungsgemäß eine starke Bindung zwischen den Magnesiakörnungen (0,09-3,15 mm) und der Matrix aus feinem MgO-Korn (< 0,09 mm) erreicht, weil beide größtenteils aus dem gleichen Ausgangsmaterial MgO bestehen. Die durch den Zusatz von relativ geringen aluminiumhydroxidhaltigen Körnungen erzeugte heterogene Gefügestruktur ist vorteilhaft für das Thermoschockverhalten der Steine. Oberraschenderweise lassen sich mit dem erfin dungsgemäßen Verfahren Magnesiasteine herstellen, die eine hohe mechanische Festigkeit und eine gute TWB besitzen. Damit können hochwertige Magnesiaerzeugnisse direkt aus dem kostengünstigeren Aluminiumhydroxid hergestellt werden. Der Aufwand zur Herstellung von Aluminiumoxid für die Spinell bildung entfällt.When using coarse grit containing aluminum hydroxide, consisting of aluminum hydroxide or a mixture of According to the invention, aluminum hydroxide and aluminum oxide become one strong bond between the magnesia grains (0.09-3.15 mm) and the matrix of fine MgO grain (<0.09 mm) because both mostly from the same raw material MgO consist. The by adding relatively minor Granules containing aluminum hydroxide produced heterogeneous Microstructure is advantageous for the thermal shock behavior the stones. Surprisingly, with the inventions process according to the invention produce magnesia stones which have a have high mechanical strength and a good TWB. In order to can produce high quality magnesia products directly from the cheaper aluminum hydroxide can be produced. Of the Cost of producing aluminum oxide for the spinel education is eliminated.
Die erfindungsgemäß eingesetzten aluminiumhydroxidhaltigen Körnungen können unter Verwendung eines Binders (z. B. Aluminiumpolyphosphat, Sulfitablauge) zu größeren Formkörpern kompaktiert und anschließend in entsprechende Kornfraktionen zerkleinert oder unmittelbar hergestellt werden. Auch bieten sich eine Vielzahl bekannter Verfahren und Vorrichtungen an: Extrudieren, Pressen, Wirbelschichtgranulatoren, Granulier teller, Sprühtrockner.The aluminum hydroxide-containing used according to the invention Grains can be made using a binder (e.g. Aluminum polyphosphate, sulfite waste liquor) to larger shaped bodies compacted and then in appropriate grain fractions crushed or produced immediately. Also offer a variety of known methods and devices: Extruding, pressing, fluidized bed granulators, granulating plate, spray dryer.
Bei der Verwendung eines Gemisches der Körnung aus Alu miniumhydroxid und Aluminiumoxid hat das Aluminiumoxid die Aufgabe, die Brennschwindung der Aluminiumhydroxid- Körnung während des Entwässerungsprozesses und der Sinterung zu reduzieren.When using a mixture of aluminum grit The aluminum oxide has the minimum hydroxide and aluminum oxide Task, the shrinkage of the aluminum hydroxide grain during the dewatering process and sintering to reduce.
Die Zusammensetzung der Ausgangsstoffe des Versatzes wird beispielsweise so berechnet, daß sich der Stein nach dem Brand aus 85 bis 98 Masse-% MgO und 15 bis 2 Masse-% Al2O3 zusammensetzt. Besteht z. B. ein fertiger Stein aus 95 Masse-% MgO und 5 Masse-% Al2O3, so beträgt der zugegebene Anteil an Aluminiumhydroxid 7,64 Masse-% bezogen auf die Gesamtmasse des gebrannten Steines. Das beim Calcinieren entstandene Was ser verdampft.The composition of the starting materials of the batch is calculated, for example, so that the stone after the fire is composed of 85 to 98% by mass of MgO and 15 to 2% by mass of Al 2 O 3 . There is z. B. a finished stone made of 95 mass% MgO and 5 mass% Al 2 O 3 , the amount of aluminum hydroxide added is 7.64 mass% based on the total mass of the fired stone. The water formed during calcination evaporates.
Auch ist es möglich, der erfindungsgemäßen Körnung oder der MgO-Körnung weitere Stoffe, z. B. Korund, feinteiliges Aluminiumoxid, Spinell, Zirkondioxid, Titandioxid, Eisen (III)-Oxid oder deren Gemische, zuzusetzen.It is also possible to use the grain size according to the invention or the MgO grain other substances, e.g. B. corundum, finely divided Aluminum oxide, spinel, zirconium dioxide, titanium dioxide, iron (III) oxide or mixtures thereof.
Wie bekannt ist, wird das Spinellkorn von kalkreichen Stoffen angegriffen. Indem erfindungsgemäß zunächst die Aluminium hydroxid- Körnung (ggf. mit Aluminiumoxid) mit einem Zusatz homogenisiert und granuliert wird, läßt sich die chemische Zusammensetzung des Versatzes auf einfache Weise verändern. Damit kann eine bessere chemische Korrosionsbeständigkeit oder ein günstigeres Ansatzverhalten der Steine erreicht werden.As is known, the spinel grain is made of lime-rich substances attacked. First, according to the invention the aluminum hydroxide grain (possibly with aluminum oxide) with an additive is homogenized and granulated, the chemical Change the composition of the offset in a simple way. This can improve chemical resistance or a more favorable approach behavior of the stones can be achieved.
Die Erfindung wird nachstehend tabellarisch an 6 Steinen näher erläutert.The invention is tabulated below on 6 stones explained.
Die verwendete Sintermagnesia besteht aus:
98,6 Masse-% MgO
0,81 Masse-% CaO
0,1 Masse-% SiO2
0,17 Masse-% Fe2O3
0,2 Masse-% Al2O3 The sintered magnesia consists of:
98.6% by mass of MgO
0.81 mass% CaO
0.1 mass% SiO 2
0.17 mass% Fe 2 O 3
0.2 mass% Al 2 O 3
Das feine Aluminiumhydroxid zur Herstellung der erfindungsge
mäßen Körnung hat folgende Merkmale:
Al2O3-Gehalt: 64,31 Masse-%
Na2O-Gehalt: 1,70 Masse-%
Glühverlust: 33,80 Masse-%
max. Korngröße (dmax): 90 µmThe fine aluminum hydroxide for producing the grain according to the invention has the following features:
Al 2 O 3 content: 64.31% by mass
Na 2 O content: 1.70% by mass
Loss on ignition: 33.80 mass%
Max. Grain size (d max ): 90 µm
Das Aluminiumhydroxid mit oder ohne Aluminiumoxidzusatz wurde mit dem Bindemittel Aluminiumpolyphosphat zu größeren Formkör pern bei 100 MPa gepreßt. Nach der Trocknung bei ca. 100°C wurden diese Formkörper zerkleinert und in die gewünschte Kornfraktion zerlegt.The aluminum hydroxide with or without the addition of alumina was with the binder aluminum polyphosphate to larger moldings pressed at 100 MPa. After drying at approx. 100 ° C these moldings were crushed and into the desired Grain fraction disassembled.
Die Aluminiumhydroxid-Körnung hat eine Rohdichte von 1,94 g.cm⁻3. Die Steine 1 und 2 wurden erfindungsgemäß hergestellt und haben einen Zusatz von Aluminiumhydroxid-Körnungen in verschiedener Korngröße und Zusatzmenge. Dem Stein 3 ist eine Aluminiumhydroxid-Aluminiumoxid-Körnung zugegeben. Der Stein 4 enthält Sintermagnesia, Schmelzkorund und Aluminiumhydroxid- Körnungen als Ausgangsmaterialien. Die übrigen Steine 5 und 6 dienen zum Vergleich, wobei der Stein 5 ein reiner Magnesia stein ohne Zusätze ist. Der Stein 6 hat dieselbe Zusammen setzung wie der Stein 1, jedoch mit einem feinen Aluminium hydroxid-Anteil.The aluminum hydroxide grain has a bulk density of 1.94 g.cm⁻ 3 . The stones 1 and 2 were produced according to the invention and have an addition of aluminum hydroxide grains in different grain sizes and quantities. An aluminum hydroxide-aluminum oxide grain is added to stone 3. The stone 4 contains sintered magnesia, fused corundum and aluminum hydroxide grains as starting materials. The remaining stones 5 and 6 are used for comparison, the stone 5 being a pure magnesia stone without additives. The stone 6 has the same composition as the stone 1, but with a fine aluminum hydroxide content.
Alle Mischungen wurden mit einer genügenden Menge wäßriger Magnesiumsulfitablauge befeuchtet und nach üblichen Formge bungsverfahren bei 120 MPa zu Steinen gepreßt, dann getrocknet und anschließend bei 1700°C und einer Haltezeit von 4 Stunden gebrannt.All mixtures became watery with a sufficient amount Magnesium sulfite waste liquor moistened and after usual Formge Practice method at 120 MPa pressed to stones, then dried and then at 1700 ° C and a holding time of 4 hours burned.
Die Rohdichte und die offene Porosität wurden nach DIN 51 065 und 51 056 geprüft.The bulk density and the open porosity were according to DIN 51 065 and 51 056 checked.
Die Heißbiegefestigkeit wird an Proben der Abmessungen 25 × 25 × 150 mm bei 1400°C und 1 Stunde Haltezeit durchgeführt.The heat bending strength is measured on samples measuring 25 × 25 × 150 mm at 1400 ° C and 1 hour hold time.
Der dynamische Elastizitätsmodul (E- Modul) wird an Proben der Abmessungen 25 × 25 × 150 mm ermittelt. Als Maß der TWB ist die Anzahl der Abschreckungen von Zylinderproben (Durchmesser × Höhe = 50 mm × 50 mm) mit Wasser (950°C ↔ 25°C) bis zum Bruch angegeben. The dynamic modulus of elasticity (modulus of elasticity) is measured on samples of Dimensions 25 × 25 × 150 mm determined. As a measure of the TWB is the number of quenching of cylindrical samples (diameter × Height = 50 mm × 50 mm) with water (950 ° C ↔ 25 ° C) up to Fraction given.
Claims (3)
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19934319741 DE4319741C2 (en) | 1993-06-15 | 1993-06-15 | Process for the preparation of magnesium oxide based refractory products |
| DE4331761A DE4331761C2 (en) | 1993-06-15 | 1993-09-18 | Process for the production of refractory products based on magnesium oxide |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19934319741 DE4319741C2 (en) | 1993-06-15 | 1993-06-15 | Process for the preparation of magnesium oxide based refractory products |
| DE4331761A DE4331761C2 (en) | 1993-06-15 | 1993-09-18 | Process for the production of refractory products based on magnesium oxide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| DE4331761A1 DE4331761A1 (en) | 1995-03-23 |
| DE4331761C2 true DE4331761C2 (en) | 1999-03-25 |
Family
ID=25926775
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE19934319741 Expired - Fee Related DE4319741C2 (en) | 1993-06-15 | 1993-06-15 | Process for the preparation of magnesium oxide based refractory products |
| DE4331761A Expired - Fee Related DE4331761C2 (en) | 1993-06-15 | 1993-09-18 | Process for the production of refractory products based on magnesium oxide |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE19934319741 Expired - Fee Related DE4319741C2 (en) | 1993-06-15 | 1993-06-15 | Process for the preparation of magnesium oxide based refractory products |
Country Status (1)
| Country | Link |
|---|---|
| DE (2) | DE4319741C2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1260289A1 (en) * | 2001-05-21 | 2002-11-27 | University of Patras | Porous plug for treatment of molten metals |
| DE102019220085A1 (en) | 2019-12-18 | 2021-06-24 | Refratechnik Holding Gmbh | Offset for the production of a coarse ceramic refractory basic product, such product and method for its production, lining of an industrial furnace and industrial furnace |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE903437C (en) * | 1944-02-29 | 1954-02-04 | Magnesital G M B H | Process for the production of volumetric magnesite bricks |
| US4385129A (en) * | 1980-11-08 | 1983-05-24 | Nippon Soken, Inc. | Method for producing a cordierite body |
| US4833109A (en) * | 1988-01-15 | 1989-05-23 | Dressers Industries, Inc. | Low thermal conductivity magnesite-spinel brick and method |
| DE4036088A1 (en) * | 1990-11-13 | 1992-05-14 | Gruenzweig & Hartmann | METAL HYDROXIDE AND MAGNESIABINDER FIRE PROTECTION AGENTS AND THEIR USE |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4126479A (en) * | 1977-09-15 | 1978-11-21 | Kaiser Aluminum & Chemical Corporation | Magnesium aluminate spinel bond for refractory brick |
| DE3532228A1 (en) * | 1984-10-02 | 1986-04-17 | Toshiba Ceramics Co., Ltd., Tokio/Tokyo | FIREPROOF COMPOSITION |
| US4847222A (en) * | 1987-05-04 | 1989-07-11 | Dresser Industries, Inc. | Basic refractory shapes |
| JPH03159956A (en) * | 1989-11-17 | 1991-07-09 | Harima Ceramic Co Ltd | Production of porous refractory for gas blowing |
| DE4040458A1 (en) * | 1990-12-18 | 1992-06-25 | Aken Magnesitwerk Gmbh | POROESES, FIRE-RESISTANT SPOOL ELEMENT |
| DE4208155A1 (en) * | 1992-03-13 | 1993-09-16 | Annawerk Gmbh | Light refractory ceramic material - has spherical pores formed by hollow sphere addn. to starting material |
-
1993
- 1993-06-15 DE DE19934319741 patent/DE4319741C2/en not_active Expired - Fee Related
- 1993-09-18 DE DE4331761A patent/DE4331761C2/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE903437C (en) * | 1944-02-29 | 1954-02-04 | Magnesital G M B H | Process for the production of volumetric magnesite bricks |
| US4385129A (en) * | 1980-11-08 | 1983-05-24 | Nippon Soken, Inc. | Method for producing a cordierite body |
| US4833109A (en) * | 1988-01-15 | 1989-05-23 | Dressers Industries, Inc. | Low thermal conductivity magnesite-spinel brick and method |
| DE4036088A1 (en) * | 1990-11-13 | 1992-05-14 | Gruenzweig & Hartmann | METAL HYDROXIDE AND MAGNESIABINDER FIRE PROTECTION AGENTS AND THEIR USE |
Also Published As
| Publication number | Publication date |
|---|---|
| DE4319741C2 (en) | 1997-12-04 |
| DE4319741A1 (en) | 1994-12-22 |
| DE4331761A1 (en) | 1995-03-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE3428252C2 (en) | ||
| DE2457579C2 (en) | Refractory mass | |
| DE2324513A1 (en) | FILTER MEDIUM WITH IMPROVED FILTRATION EFFICIENCY | |
| DE3521112C2 (en) | Refractory chromia-alumina composition and method of manufacture | |
| AT395846B (en) | MAGNESIA ALUMINUM OXIDE SPINEL CLINKER AND METHOD FOR THE PRODUCTION OF FIRE RESISTANT PRODUCT BY USE OF THE SAME | |
| DE4331761C2 (en) | Process for the production of refractory products based on magnesium oxide | |
| DE4334683C2 (en) | Process for the preparation of refractory compositions | |
| DE2044289C2 (en) | Process for the production of a refractory sintered material | |
| DE2533774C2 (en) | Ceramic mass, process for its production and use of the mass for the production of earthenware products | |
| DE3108003C2 (en) | Refractory chromite magnesia bricks and masses, processes for their production and their use | |
| DE2240771C3 (en) | Process for the production of refractory magnesium oxide moldings | |
| DE19607605C2 (en) | Process for producing a coarse ceramic shaped body based on magnesia and / or fired dolomite and the use thereof | |
| AT394038B (en) | METHOD FOR PRODUCING A BURNED, FIREPROOF MAGNESIA STONE BASED ON SINTERMAGNESIA AND FINE DISTRIBUTED CIRCONIZED SILICONE | |
| AT223996B (en) | Basic refractory bricks and processes for their manufacture | |
| AT202506B (en) | Process for the production of highly refractory magnesite-chrome molded bodies | |
| DE19737519C2 (en) | Process for producing a coarse-ceramic shaped body based on magnesia and / or fired dolomite and its use | |
| DE661269C (en) | Process for the production of glass tub blocks and other refractory items which are exposed to the attack of molten glass | |
| DD233836A1 (en) | METHOD FOR PRODUCING HIGH QUALITY TONER DEZEMENTS WITH ADVANTAGEOUS HYDRATION AND HIGH TEMPERATURE BEHAVIOR | |
| AT345144B (en) | METHOD OF MANUFACTURING PRE-REACTED MAGNESIA-CHROMERZ GRAIN | |
| DE2044885C (en) | Process for the production of chrome ore grains suitable for refractory purposes | |
| EP4077239A1 (en) | Backfill for producing a basic heavy-clay refractory product, such a product and method for producing same, lining of an industrial furnace, and industrial furnace | |
| AT255955B (en) | Process for the production of refractory moldings | |
| DD275664A1 (en) | PROCESS FOR PRODUCING FIRE-RESISTANT MASSES | |
| DE1117027B (en) | Process for the production of silica stones from sands | |
| DE1815438C (en) | Refractory, burnt magnesite stone |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AF | Is addition to no. |
Ref country code: DE Ref document number: 4319741 Format of ref document f/p: P |
|
| OP8 | Request for examination as to paragraph 44 patent law | ||
| 8122 | Nonbinding interest in granting licences declared | ||
| 8127 | New person/name/address of the applicant |
Owner name: VU, TUAN ANH, DR.-ING., 56422 WIRGES, DE ULBRICHT, |
|
| AF | Is addition to no. |
Ref country code: DE Ref document number: 4319741 Format of ref document f/p: P |
|
| AF | Is addition to no. |
Ref country code: DE Ref document number: 4319741 Format of ref document f/p: P |
|
| D2 | Grant after examination | ||
| 8364 | No opposition during term of opposition | ||
| 8340 | Patent of addition ceased/non-payment of fee of main patent |