PURPOSE: To prevent the occurrence of nonuniform heating or cooling of a package by treating the package by heating or cooling while it is confined spatially between plate-like blades, a bulkhead plating and the inner wall of a container when a rotating cylinder having the plate-like blades passes intermittently through treating liquid inside a semicylindrical liquid container.

CONSTITUTION: A porous bulkhead plating 6 is provided along the middle of a rotating cylinder 3 and around its rotating periphery enclosing a rotational shaft 1. As the rotating cylinder 3 makes an intermittently rotational movement, a package received by a plate-like blade 2 passes through a semicylindrical liquid container 4. During this time, the package is confined spatially between two adjacent blades 2, the bulkhead plating 6 and the inner wall 8 of the container without rising to the surface of a liquid, so as to be treated with a treating liquid 13 for heating or cooling.