40 Transactions of the Royal Canadian Institute 



has proved of value in the present experiments, namely that there 

 are fluid slags consisting essentially of silica, titania and alumina. 



Methods 



A brief account of the means and methods used in attacking this 

 problem follows. With an object in view other than the simple pro- 

 duction of pig-iron, a careful study was made of the chemical relations 

 of the various materials composing the ore, as set down above. Labor- 

 atory tests were made, and these led to the undertaking, under private 

 auspices, of smelting tests on a small commercial scale. The slags so 

 produced seemed worthy of detailed study, and the interest and financial 

 aid of the Advisory Research Council were obtained for this purpose. 

 The study is still far from complete but the results to date are believed 

 to be of sufficient public interest to warrant the presenting of this paper. 



Furnace 



Since the softening points of synthetic mixtures representing slags 

 has been thoroughly investigatedS and since the relation between such 

 determinations and the fluidity of actual slags is an unknown factor,^ 

 it was decided to approximate as closely as possbile to large-scale smelting 

 conditions from the beginning. The electric furnace was chosen as the 

 best means of smelting for several reasons. First and foremost is the 

 fact that with even a small electric furnace, high temperatures can be 

 got with comparative ease. Then it is to our advantage in Central 

 Canada to have, if possible, smelting methods independent of imported 

 coal. Another cogent reason for adopting the electrical method is that 

 it is a "coming" method. As has been stated aptly by more than one 

 authority (possibly enthusiasts), if our knowledge of electric furnace 

 operation approached in completeness our knowledge of the blast fur- 

 nace, the latter would soon be an obsolete appliance. The raw materials 

 used were prepared in no especial way, being such as would be used in 

 large-scale practice. 



The furnace, built for this purpose, is an iron box, balanced on 

 trunnions, lined and roofed with silica brick round a crucible nine inches 

 in diameter. The pouring spout serves also as charging door. Single- 

 phase electric current is supplied at any desired voltage through a 

 graphite electrode built into the bottom of the furnace, and an adjustable 

 electrode of two inches in diameter through the roof. The power used 



^Stansfield & Wissler; Rossi; and Cox and Lennox, as above. 



^Feild, A. L., — "A Method for Measuring the Viscosity of Blast-Furnace Slag at 

 High Temperatures." U. S. Bureau of Mines, Tech. Paper 157, 1916. 

 Cox and Lennox, as above. 

 Johnson, J. E., as above, p. 202. 



