Sectioned bubble tray distillation over a wide range of feed composition and bubble tray loading

摘要

A volatile component over a wide range of concentrations in a multicomponent feed to a distillation column (3) is accomodated at varying feed flow rates without destroying bubble tray efficiency. This effected by establishing on a bubble tray (10) a plurality of separation zones having discrete and different liquid pressure seals above bubble apertures (14, 19, 24) on the tray. To avoid entrainment, vapor flow restrictors (15, 25, 35) are utilized with bubble apertures in at least one separation zone having less liquid head to offset a tendency of proportionately increased vapor flow through such a bubble aperture during operation of separation zones having a liquid head differential. Intermediate weirs (6, 8) or bubble apertures (58, 64) having different elevations below a liquid level on the tray can be used to establish such separation zones of differing liquid heads (9, 7, 5).