GB1373941A - Refractory shapes - Google Patents

Abstract

1373941 Refractory shapes STEETLEY (MFg) Ltd 6 Jan 1972 [13 Jan 1971] 1688/71 Heading C1J A refractory shape is formed from a mixture containing a refractory material, a cokeable carbonaceous substance and 1-10 wt. per cent based on the weight of refractory material of a substance containing substantially lime and/or magnesia and having a particle size less than 15 microns. The carbonaceous substance is one or more of tar, pitch, bitumen, petroleum distillate residue, asphalt, creosote, and a resin. The refractory material may be dead burned lime, dead-burned dolomite, dead-burned magnesia or carbon. The lime- and/or magnesiacontaining substance may be dolomite, magnesite or limestone and be calcined or deadburned. Viscosity increasing catalysts (e.g. aromatic sulphonyl halides, aromatic or heterocyclic alcohols or aldehydes, aromatic nitrocompounds, ammonium persulphate, potassium permanganate, potassium dichromate, sodium nitrate, oxides of iron, manganese nickel, lead or the rare earths, chlorides of Al, Fe and Zn or nitric oxide or chloride may be added to the carbonaceous substance. The refractory mixture may also contain zirconium or chromium compounds. Prior to mixing the refractory material may be heated to 100 to 500‹ C. and the carbonaceous substance up to 200‹ C. The Specification describes the formation of shapes from the mixtures and also their tempering and stoving. In the examples the preparation of shapes from various of dead-burned magnesia, active magnesia, calcined dolomite, deadburned dolomite, pitch and tar is described.