Description |
Chloride fume is the product obtained by the precipitation of the solids in the gases evolved in the chloride-volatilization process. This process has passed through the experimental and semi-commercial stages and at present is being tried out commercially in several of the Rocky-Mountain States. It is particularly adapted to the treatment of oxidized and semi-oxidized ores such as are abundant in these districts. In the present method of application the process consists of feeding the ore, with a small percentage of chloridizing agent, into a rotary kiln of they type used in cement manufacture. The discharge end of the furnace is headed with an oil burner to temperatures varying from 700C to 1000C. Chloridizing agent is sometimes fed into the fire end of the kiln, this being accomplished by means of an air pressure injector. During the passage of the ore through the rotary furnace the metals are converted into chlorides or oxychlorides and volatilized as such. The gases containing the metallic vapors are then usually passed through a Cottrell treater in order to precipitate the fume. This fume product, obtained from the Cottrell precipitators, is the chloride fume that has been used in the experimental work herein presented. |