Abstract

The invention relates to a refractory cement composition comprising: - a proportion of 35 to 70 wt.% of a coarse-grain fraction of at least one refractory raw material having grain sizes of at least 0.5 mm; - a proportion of 15 to 30 wt.% of a fine-grain fraction of the at least one refractory raw material having grain sizes smaller than 0.5 mm; - a proportion of 0 to 20 wt.% of fine-grain calcined aluminium oxide having grain sizes smaller than 0.1 mm; - a proportion of 0 to 2 wt.% of fine-grain magnesium oxide powder having grain sizes smaller than 0.1 mm; - a proportion of 2 to 7 wt.% fine-grain aluminium metal powder having grain sizes smaller than 100 µm; - a proportion of 2 to 8 wt.% of at least one fine-grain carbon carrier having grain sizes smaller than 100 µm, wherein the at least one fine grain carbon carrier contains or is carbon black and/or graphite; - a proportion of 4 to 20 wt.% of an aqueous colloidal silica sol suspension, wherein the silica sol suspension contains a solids proportion of 30 to 50 wt.% of amorphous nanoscaled silicon dioxide particles. The invention also relates to a method for producing a fired cement element from a refractory cement composition.

IPC Classes  ?

• C04B 35/66 - Monolithic refractories or refractory mortars, including those whether or not containing clay
• C04B 35/103 - Refractories from grain sized mixtures containing non-oxide refractory materials, e.g. carbon
• C04B 35/18 - Shaped ceramic products characterised by their compositionCeramic compositionsProcessing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxides based on silicates other than clay rich in aluminium oxide
• C04B 35/185 - Mullite
• C04B 35/443 - Magnesium aluminate spinel
• C04B 35/63 - Preparing or treating the powders individually or as batches using additives specially adapted for forming the products

Abstract

The invention relates to a refractory concrete composition, comprising: - a proportion of 35 to 70 % by weight of a coarse grain fraction of the at least one refractory raw material having grain sizes smaller than 0.5 mm; - a proportion of 15 to 30 % by weight of a fine grain fraction of the at least one refractory raw material having grain sizes smaller than 0.5 mm; - proportion of 0 to 20 % by weight of fine-grained calcined alumina having grain sizes smaller than 0.1 mm; - a proportion of 0 to 2 % by weight of a fine-grained magnesium oxide powder having grain sizes smaller than 0,1 mm; - a proportion of 2 to 7 % by weight of a fine-grained aluminum metal powder having grain sizes smaller than 100 µm; - a proportion of 2 to 8 % by weight of at least one fine-grained carbon carrier having grain sizes smaller than 100 µm, with said at least one fine-grained carbon carrier including, or being, carbon black and/or graphite; - a proportion of 4 to 20 % by weight of an aqueous colloidal silica sol suspension, with said silica sol suspension including a solids content of amorphous nano-scaled silicon dioxide particles of 30 to 50 % by weight. Further, there is provided a method of producing a fired concrete element from a refractory concrete composition.

IPC Classes  ?

• C04B 35/103 - Refractories from grain sized mixtures containing non-oxide refractory materials, e.g. carbon
• C04B 35/18 - Shaped ceramic products characterised by their compositionCeramic compositionsProcessing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxides based on silicates other than clay rich in aluminium oxide
• C04B 35/185 - Mullite
• C04B 35/443 - Magnesium aluminate spinel
• C04B 35/63 - Preparing or treating the powders individually or as batches using additives specially adapted for forming the products
• C04B 35/66 - Monolithic refractories or refractory mortars, including those whether or not containing clay