To improve the efficiency of recovering an aluminum.
A residue filtering-separation apparatus 42 removes aluminum dross from aqueous solution composed of sodium aluminate and the aluminum dross. The residue filtering-separation apparatus 42 is provided with: a first aqueous solution tube 88 through which the aqueous solution flows in; a filter press 80; and a second aqueous solution tube 90. In the filter press 80, the aluminum-dross is filtered from the aqueous solution passing through the first aqueous-solution tube 88. The second tube is connected to the filter press 80, and the aqueous solution, from which the aluminum dross is removed, passes therethrough. The residue filtering-separation apparatus 42 is further provided with a heat-insulating material. The heat-insulting material suppresses the lowering of liquid temperature of the aqueous solution during passing through the first aqueous-solution tube 88 and the second aqueous-solution tube 90.
TANAKA YUICHI
KOBAYASHI YASUSHI
SHINBA KOZO
IIDA KATSUYASU
MIYAMOTO NORIHIKO
NIPPON LIGHT METAL CO
ITEC CO LTD