| Description |
[ii], 19 leaves : illustrations |
| Summary |
"Many attempts have been made in the last twenty years to smelt zinc ores in the electric furnace. The disadvantages of the present retort process have been discussed so often that they need not be dwelt upon here. The principle ones are, the low thermal efficiency of the retort furnace, low metal recoveries, small smelting units necessary, short life of the retorts and the difficulty of treating impure and low grade ores. Electric smelting offers remedies for most of these difficulties"--Introduction, leaf 1. |
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