To make a slag generating portion and an ingeneration portion of slag in a melting and storing station.

This melting furnace includes a melting chamber 1 whose upper and lower peripheries are covered, and a vortex chamber 2 for melting material to be treated, wherein the vortex chamber is provided in the melting chamber, molten metal enters and leaves the melting chamber from the vortex chamber through a pair of communicating ports, and the melting chamber is provided with an openable door 5 for scraping away slag. A partition wall 7 partitioning at least the lower part in the melting chamber into two chambers 8, 9 as viewed in a plane is extended to separate from the vortex chamber 2, one communicating port 3 is communicated with one of the two chambers, the other communicating port is communicated with the other of the two chambers. One of the two chambers is taken as a heat receiving chamber 8 where molten metal is taken in the vortex chamber 2, and the other chamber of the two chambers is taken as a slag scraping chamber 9 to which molten metal is discharged from the interior of the vortex chamber. A runner 7a communicating the two chambers to each other is formed in the lower part of the partition wall 7. The partition wall partitions only the lower part in the melting chamber into two chambers when viewed in a plane, and the two chambers are communicated with each other above the partition wall.