Studies in the Distribution of Temperature through Molten Glasses in a Tank Melting Furnace. Part II. The Effect of Iron Oxide and its State of Oxidation on Heat Transmission

JSGT 1945 V29 T170-T191

The effect both of total iron oxide content, and of the proportion of the ferrous oxide in that total, on the temperature distribution throughout a mass of glass heated at the surface in a laboratory scale tank furnace was systematically studied by comparing results for twenty-two glasses. The small tank was divided into two parallel compartments which ran down the tank in the direction of the flame. One compartment was charged, in every measurement, with the colourless parent glass of percentage composition SiO₂ 73·5, Al₂O₃ 1·5, CaO 8·9, Na₂O 16·0 and Fe₂O₃ 0·07; the other contained the derived glasses obtained by the progressive addition of iron oxide (Fe₂O₃) up to a maximum of 3·75%. The ferrous oxide content, expressed as a percentage of the total iron, in the series of glasses was varied from 7·6 to 68·5%, this variation being brought about partly by altering the total iron oxide, partly by melting and heating the glasses under conditions varying from oxidising to strongly reducing. All the tests were carried out under controlled conditions involving the consumption of 12 cu. ft. of town gas per minute.

Robert Halle & W. E. S. Turner