| 摘要 |
<p>PROBLEM TO BE SOLVED: To rapidly and stably recover valuable metals in powder and granular materials at a good yield by connecting at least two condensers varying in cooling temp. to a treating chamber for heat treating the powder and granular materials in vacuum. SOLUTION: At least the two condensers 72, 71, etc., varying in the cooling temp. are connected to the treating chamber 21 of this device. In the case of connection of, for example, the two condensers, the condenser (hereafter, A) of the relatively high cooling temp. is connected as one thereof and the condenser (hereafter, B) of the relatively low cooling temp. as another one. When the powder and granular materials are heated under vacuum, extraneous materials, such as moisture and fats and oils, coexisting in the powder and granular materials evaporate in the initial stage of the low temp. and, therefore, these materials are captured by A. A reducing gas is supplied from a gas supply pipe 51 to reduce the metal oxides in the powder and granular materials to the corresponding metals in the subsequent state of the high temp. and, thereafter, these metal vapors are condensed in B and are separately recovered.</p> |
