To particularly improve a heat exchange efficiency in a preheating zone by sequentially forming the preheating zone, baking zone and a cooling zone from above in a vertical furnace body, and providing a moving route for moving a material to be baked from an upper end of the body toward a lower end in the body, thereby uniforming temperature distribution in the same section of the body.

A vertical furnace body 1 continued in a vertical direction is, for example, formed in a cylindrical state, and a preheating zone 2, a baking zone 3 and a cooling zone 4 are sequentially formed from above the body 1. An exhaust duct 5 is provided on an outer periphery of the zone 2 to suck atmospheric gas rising from below the body 1. High temperature baking gas of many baking burners 6 provided on an outer periphery of the zone 3 is raised in the body 1 buoyancy, sucked by the duct 5 of the zone 2, and shooting nozzle 7 of cooling air is provided on an outer periphery of the zone 4. A moving route obtained by stacking a kiln implement 8 for transferring material to be baked from an upper end of the body toward a lower end of the body is provided at a center of the body 1 in a vertical direction.