A high viscosity liquid is fed into a rotation pack bed at a position with a
distance
far enough from a rotation axis, creating a centrifugal force exerted on the high
viscosity liquid overwhelming a drag thereof, so that it can flow radially through
the rotation pack bed. A high pressure gas is introduced into the rotation pack
bed peripherally and/or a suction force source is connected to a position near
the rotation axis, so that a volatile component contained in the high viscosity
fluid is entrained in the gas counter currently flowing through the rotation pack
bed and withdrawn from the position near the rotation axis, or the volatile component
exits from the position near the rotation axis in gas phase, and thus the volatile
component is removed from the high viscosity liquid. A second fluid can also be
fed into the rotation pack bed to react with the high viscosity liquid, so that
a reaction product is formed, and a volatile side product is removed at the same time.
