To improve the recovery rate of solder from a dross lump produced at the time of soldering operation.
A dross lump 2 produced at the time of soldering operation is recovered, and is heated by a heating furnace 1. After the fusion of solder 3, further, heating is performed till dross 4 is made into a dry ash shape. The ash-shaped dross 4 is scooped up with a perforated hand ladle 5 together with the fused solder 3 from the heating furnace 1, and they are sifted out from the upper part of a cooling tank 6 stored with a cooling liquid 7. The solder 3 in a fused state is made into a drop shape or a linear shape, and falls down. On the other hand, the ash-shaped dross 4 falls down in a dry shape. They are solidified with the cooling liquid 7 in the cooling tank 6. Thus, the dross lump 2 is separated into the powdery dross 4 having a pore size smaller than that of the perforated hand ladle 5 and the solder 3 larger than the powdery dross 4. At the time when they are scooped up with the perforated hand ladle 5, and are sifted out, the solder 3 of high purity is left in the perforated hand ladle 5.
OKADA KIYOSHI
INOUE TOSHIAKI
ISHIKANE ATSUSHI
Hideka Tanaka
Yoshiyuki Shiraishi
Kunihiko Shiromura
Tsuyoshi Kumano
Hiroaki Yamane