Technical and Economic Features in the Utilization of Blast Furnace Slag in Glass Manufacture

Abstract

The object of this investigation was to find a more advantageous method for the disposal of blast furnace slag. As a result of this investigation, a method was developed for the production of four types of glass: (1) A transparent aluminum glass, (2) an opaque black glass, (3) a translucent "opal" glass, and (4) a laboratory or "chemical" glass. The optimum conditions for carrying out the various processes were determined. The various objections to the use of slag for glass manufacture were discussed in detail and an explanation offered as to how these objections were overcome. The transparent aluminum glass and the black opaque glass were made on a semi-commercial scale. Drawings and specifications together with an estimate of the cost of the necessary equipment for commercial or large scale manufacture of the slag glasses are included. This data was supplied by the Simplex Engineering Company, and the Amsler-Norton Company. The cost of the raw materials for producing the various slag glasses was determined and the results compared to various commercial glasses. The physical and chemical properties of the various glasses were determined and the results compared with commercial glasses. Various economic features were discussed with the point in view of determining the commercial feasibility of the process. The results showed that there was a saving in the cost of the raw materials from 35 to 75 per cent and the glasses were of superior quality with respect to thermal endurance, chemical stability, tensile strength and resistance to breakage by impact. An additional advantage in the case of the black glass was the high gloss and true black color. An advantage possessed by all the slag glasses was their resistance to shattering when broken.