| 摘要 |
<p>1508847 Impregnating refractories SHINAGAWA REFRACTORIES CO Ltd and NIPPON OIL CO Ltd 18 June 1975 [25 June 1974] 25961/75 Heading D1P A refractory, e.g. a dolomite, magnesite, alumina, silica or carbon brick is impregnated to render it resistent to slag erosion and slaking, with a thermoplastic resinous material which is obtained as the residue after removal of a light fraction of boiling point less than 200‹C measured at 100mm Hg from (a) a heavy oil obtained by steam cracking of petroleum, (b) a polymerisation product of such a heavy oil, or (c) a mixture of (a) and (b), which residue has a benzene-insoluble fraction content of less than 10% by weight. Steam cracking may have been carried out at 700-1,000‹C. Polymerisation where effected, may have been with or without a catalyst e.g. a metal salt or a radical catalyst, or under oxidising conditions. The refractory may be preheated and de-gassed under vacuum prior to impregnation, and the impregnant may be applied at an elevated temperature (preferably below 250‹C) and. under normal or superatmospheric pressure. The impregnant may be applied in the form of a solution in a petroleum solvent e.g. pale oil lubricating oil or heavy fuel oil. The petroleum from which residue is derived may be gasoil, naphtha, kerosene or a mixture thereof.</p> |
