ILDFAST FORINGSMATERIALE SOM ER RESISTENT MOT NATRIUM OG NATRIUMSALTER.

摘要

Refractory linings (28) for use in containers (20) which contact sodium or sodium salts at high temperatures and containers (20) provided with such linings, e.g. reduction cells and furnaces. The linings comprise three layers (29, 30 and 31) at least after an initial period of use. The first layer (29) is made of aluminosilicate material having an alumina:silica ratio of at least 0.85 and a porosity of about 25% or less. The second layer (30) is made of an aluminosilicate material having an alumina:silica ratio of at least 0.85 and a porosity in the range of about 25-50%. The third layer (31) is of highly insulating refractory material adjacent to an outer wall (22) of the container having a porosity of more than about 50%. The aluminosilicate used for one or more of the layers may be self-densifiable or non-self-densifiable calcined red mud. The linings resist degradation by the sodium or sodium salts while providing good thermal insulation.