Recent Smelting Practice at Noranda

A paper describing the Noranda smelter was presented at the 1930 annual meeting of the Institute (1). A lacer article appeared in the Trans-actions of the A.I.M.&M.E. in 1933. Since that time there have been many changes and improvements in plant operation and it is the abject of this paper to give an account of developments up to the beginning of 1939. The Noranda smelter was built originally for a capacity of 30,000 tons a month. At present, the average tonnage being treated is 110,000 tons a month, the tonnage of custom ores alone amounting to almost the total rated capacity of the original plant. This increase has been accomplished by increasing the capacity of the reverberatory furnaces from 700 tons of solid charge per furnace day in 1928 to 1,500 tons per day at the present time. In 1935, it appeared chat the limit of furnace capacity had been reached at about 1,300 tons of charge per day because of the short life of the sprung silica arches. However, the adoption of the suspended magnesite roof, which had been developed at the Flin Flou smelter of the Hudson Bay Mining and Smelting Company, overcame this difficulty and it is believed that the limit of the capacity of the present reverberarory furnaces has not been reached. A brief account of the changes to equipment in the various departments will be given, followed by a description of the more important features of present smelter practice.