| 摘要 |
<p>PROBLEM TO BE SOLVED: To make it possible to recover valuable metals, such as Co and Ni, at a good yields by roasting used lithium secondary batteries, then pulverizing and sieving these batteries, mixing the valuable metal concentrate which is the minus sieve thereof with a calcium compd., melting the mixture and removing the formed slag. SOLUTION: The used lithium secondary batteries are roasted at about 350 to 1000 deg.C, by which org. materials are decomposed, burned or evaporated and are removed. The roasted matter is pulverized and is sieved by using a sieve below about 3350μm. The primary valuable metal concentrate represented by Co and Ni is obtd. as the minus sieve. This concentrate is mixed with the Ca component, such as calcium hydroxid and is heated to a temp. above the temp. at which the metal components in the concentrate melt. The Al contained as an impurity in the melt is removed into the slag and the metals (the alloys of the valuable metals) are recovered as the secondary valuable metal concentrate. At this time, the Al of the impurity is oxidized and is brought into reaction with the CaO component in the Ca compd., by which the Al2 O3 -CaO slag having a low m.p. and good flow property is formed.</p> |
