Service of zirconia refractories in continuous furnaces for quartz glass melting

Abstract

Data are given on the durability of baddeleyite refractories of grade TsTsPP, which contain no stabilizing additives, in operation in the lining of continuous furnaces for melting quartz glass at the Dzerzhinskii Glass Works. In operation in contact with molten quartz at a temperature of (2000 Mp 10)°C, the average (for a year) durability has increased up to 82.5 days compared with the lining made of refractory sectors of CaO-stabilized ZrO2, which had a durability in these furnaces up to 25 days. It is noted that the durability of furnace linings made of baddeleyite refractories is limited by the durability of the roof plates. With the use of a water-cooled roof, the durability of the furnace lining was increased up to 267 days, but the heat losses were higher. The results of comparative tests of baddeleyite refractories with different porosity (between 9.6% and 22.3%) and of those based on natural baddeleyite of natural grain size and on electrofused ZrO2 are given. No differences in their durability have been established. The results of examining the refractories after their operation in furnaces are also considered.