Postmortem Of A Conventional Silica Brick From A Soda-Lime Float Glass Furnace Crown

In the 1990s, a silica brick retrieved from a conventional air-fired float glass furnace was analysed to determine its alteration in service. Changes in its crystallinity, thermal expansion, chemistry, bulk density, porosity and physical appearance were determined at 6 different locations, going from its hot face to its cold face. Testing results and physical observations showed it to be completely altered from its original state. Considerable differences were also noted between the six different locations, going from its hot face towards its cold face. Such extensive alterations are attributed to its reactions with the alkali present in the furnace atmosphere and also the temperature and thermal gradient in which it operated.