Abstract: A non-ferrous metal smelting furnace including a preheating tower includes a smelting chamber, provided below the preheating tower, a combustion chamber, provided adjacent to the preheating tower, a lower portion of which communicates with the smelting chamber, the combustion chamber being provided with a burner for generating a combustion gas on its upper furnace body, and a gas diffusion mechanism, provided in the smelting chamber, and including retaining members for constituting a plurality of openings distributed between the smelting chamber and the preheating chamber in the preheating tower and for retaining a material in the preheating tower.

Abstract: A preheating mechanism for preheating a source metal for melt includes a combination of independent combustion and preheating devices. The mechanism also includes a high-temperature gas conduit for connecting the combustion device and the preheating device, a low-temperature gas conduit for connecting the preheating device and an exhaust gas chimney, a branch pipe branched from the low-temperature gas conduit and connected to the high-temperature gas conduit, and a short-cut gas conduit for connecting a conduit portion at a combustion device side from a coupling portion between the high-temperature gas conduit and the branch pipe to a conduit portion at an exhaust gas chimney side from a branch portion between the low-temperature gas conduit and the branch pipe. A diluting mechanism is arranged in the short-cut gas conduit. A valve with a variable motor is arranged in the branch pipe.