The Smelting of Titaniferous Iron Ores 39 



The most complete information available about the softening points 

 of mixtures containing titania is given by Dr. Stansfield.^ His investi- 

 gation also included two furnace runs from which he concluded that 

 silica as well as limestone should be used to flux the ore. 



Accepting the idea that the slag is the proper point of attack in 

 attempting to smelt an iron ore, a comparison of the slags produced in 

 the furnace runs quoted above will be instructive. 



Titania Slags 



Ill(b) III(c) IV V VI 



12.50% 6.30% *2. 76% 1.15% 



21.71 22.16 28 36.75 32.40 



18.38 9.51 22.65 35.80 



9.05 5.34 2.67 6.36 



13.76 15.58 **14 10.14 15.17 



24.73 40.81 10 25.16 7.09 



98.95% 100.01% 100.53% 100.13% 99.70% 100.13% 97.97% 



(*Fe O reduced to normal.) (**+Fe O). 



I Mclntyre furnace, Adirondack River, 1840-56. 



11. Norton, England— 1868. 



in. Rossi, Perth Amboy, N. J.— 1892. 



(a) First slag from run. 



{b) Slag, first eight hours of run. 



(c) Slag toward end of run. 



IV. Bachman's run. Port Henry, N.Y. — 1914. 



V. Stansfield's run, Montreal, 1916. 



VI. Run on Taranaki sands. New Plymouth, N.Z., 1918. 



Of these slags, I, II, III (b), and V are much alike, in that the pro- 

 portions of silica, lime plus magnesia, and titania in each are nearly equal, 

 and so the composition of the slags is approximately that of the mineral 

 sphene. This result was arrived at in I by empirical means; in II 

 deliberately, in imitation of the easily fusible mineral; in III (b) and V by 

 calculation, following pot tests and cone tests. IV and VI follow regular 

 iron blast-furnace practice with titania as a minor constituent. Ill (c) 

 shows very high titania, at the expense partly of silica and partly of 

 lime. In each of these cases the operator or investigator has conceded, 

 by accident or by design, that a fairly high percentage of silica is necessary 

 in order to get a fluid slag. The slag III (a) only, which Rossi obtained 

 accidentally by fluxing the lining of his furnace, brings out the point that 



^Stansfield, A , and Wissler, W. A. — "The Smelting of Titaniferous Ores of Iron.' 

 Trans. Royal Soc. Canada, Vol. X, 1916. 



