Structured packing module for mass transfer column and process involving same

A process for causing mass transfer and/or heat exchange between fluid streams flowing within a mass transfer column having structured packing modules positioned within an open internal region formed by a shell of the column, said structured packing modules comprising a plurality of upright, parallel-extending, plates having corrugations, the plates being arranged with the corrugations of adjacent plates extending in a criss-crossing fashion with respect to each other and being secured in spaced apart relationship along their entire lengths by spacer elements that are positioned at top and bottom edges of the plates, the corrugations of adjacent plates being spaced from and not in contact with each other or other structures along substantially an entire length of the corrugations to form an open spacing between facing surfaces of the plates, said process comprising the step of passing said fluid streams through said structured packing modules along generally unimpeded flow paths formed by said surfaces of the plates and said open spacing to cause said mass transfer and/or heat exchange on surfaces of said plates.