Thermal separation process

Abstract

A thermal separation process between a gas ascending in a separating column and a liquid descending in the separating column, which comprise (meth)acrylic monomers, wherein the separating column comprises a sequence of crossflow mass transfer trays, the crossflow mass transfer trays of which have passage orifices for the ascending gas in crossflow direction both in front of and beyond a downcomer for the descending liquid, and such crossflow mass transfer trays and one such crossflow mass transfer tray in a sequence of crossflow mass transfer trays present in a separating column.

1 - 27 . (canceled) 
     
     
         28 . A circular mass transfer tray, comprising passage orifices and at least one downcomer with a downflow orifice only in one half and does not have any feed area free of passage orifices in the other half, wherein the tray has passage orifices for gas ascending in working operation, proceeding from the center of the downflow orifice of the at least one downcomer, not only in the tray area in front of the at least one downcomer in the direction of the opposite half, but also in the tray area beyond the at least one downcomer in the opposite direction. 
     
     
         29 . A sequence, present in a separation column, the sequence comprising at least two identical crossflow mass transfer trays comprising at least one downcomer through which liquid descends from a particular crossflow mass transfer tray, the crossflow mass transfer trays being arranged one on top of another within the sequence in the separation column, such that two crossflow mass transfer trays in the separation column, one of which follows the other in the downward direction, are each mounted offset from one another by 180° about the longitudinal axis of the column, as a result of which their downcomers are on mutually opposite sides of the separation column,
 wherein: 
 the at least one downcomer of the upper of two successive crossflow mass transfer trays constitutes at least one upcomer for the crossflow mass transfer tray below it, through which liquid descends from the upper crossflow mass transfer tray as at least one feed to the crossflow mass transfer tray below it; 
 a liquid descending through the at least one upcomer from the upper to the lower crossflow mass transfer tray, viewed over the (entire) lower crossflow mass transfer tray, flows from the at least one feed to the lower crossflow mass transfer tray across the tray to the at least one downcomer of the lower crossflow mass transfer tray; 
 passage orifices are situated between the at least one feed to the lower crossflow mass transfer tray and the at least one downcomer of the lower crossflow mass transfer tray, through which gas ascends through the lower crossflow mass transfer tray; and 
 within the sequence of identical crossflow mass transfer trays, the lower of two successive crossflow mass transfer trays in each case, in the direction of the crossflow from the at least one feed thereof to the at least one downcomer thereof, additionally has at least one passage orifice beyond at least one downcomer through which gas ascends.