Section III, 1919 , [217] Trans. R.S.C. 



Possible Economies in the Electric Smelting of Iron Ore 



A Preliminary Note 



By Dr. Alfred Stansfield, F. R.S.C. , 



(Read May Meeting, 1919.) 



The electric smelting of iron ores was first undertaken about 

 twenty years ago, and is now in regular commercial operation in 

 Sweden and to a small extent elsewhere. The merits and limitations 

 of this process can be visualized by comparing it with the correspond- 

 ing process in the iron blast furnace. 



Speaking generally, iron ores can be smelted in the blast furnace 

 with the expenditure of one ton of fuel (coke or charcoal) for each 

 ton of pig iron produced. In the electric furnace, on the other hand, 

 the fuel needed is replaced in part by electrical energy, and the pro- 

 duction of one ton of pig iron in this furnace is found to require about 

 four-tenths of a ton of fuel (usually charcoal) and about four-tenths of 

 an electrical horse power year. 



In view of the comparative costs of coke and electrical energy, 

 it is clear that the saving of six-tenths of a ton of coke will usually 

 be insufficient to pay for four-tenths of an electrical horse power year, 

 although where charcoal is used in the blast furnace and where electri- 

 cal energy is exceptionally cheap, the saving in fuel may pay for the 

 electrical power. 



The use of charcoal in the blast furnace was, at one time, very 

 general, but at present, owing to its higher cost and the other limita- 

 tions of its use, charcoal smelting is only practised to a small extent. 



In Sweden magnetite iron ores of unusual purity have for a long 

 time been smelted with charcoal, in blast furnaces, for the production 

 of a special quality of white pig iron which commands a high price. 

 Under these conditions the electric furnace has been found to be more 

 economical than the blast furnace and is therefore replacing it to a 

 large extent. In other countries, such as Canada, electric power is in 

 general more costly than in Sweden. As a rule, the ores are not pure 

 enough for the production of the finest iron, and, in addition to this, 

 there is not a large enough market for a high-priced pig iron of special 

 quality. 



There are many districts in Canada where iron ores and water 

 power can be obtained near together and where coke, suitable for 



Sec III, Sig. 15 



