The present disclosure relates generally to processes for separating an effluent in an acetic acid production unit. Accordingly, one aspect of the disclosure provides a process including transferring at least a portion of a carbonylation reaction effluent to the bottom section of a tank, evaporating at least a portion of the effluent to form a vapour fraction, spraying a spray liquid onto a porous demister surface of a demister section of the tank, collecting and returning a liquid fraction of the effluent from at least one chimney tray in the tank to a fractionation section or the bottom section of the tank, and withdrawing from a top section of the tank at least a portion of the vapour fraction, the vapour fraction comprising acetic acid, the vapour fraction having been passed from the bottom section through the fractionation section, and then through one or more chimneys of the at least one chimney tray, and then through the spray section, and then through the porous demister surface of the demister section.

The present disclosure relates generally to processes for separating an effluent in an acetic acid production unit. Accordingly, one aspect of the disclosure provides a process including transferring at least a portion of a carbonylation reaction effluent to the bottom section of a tank, evaporating at least a portion of the effluent to form a vapour fraction, spraying a spray liquid onto a porous demister surface of a demister section of the tank, collecting and returning a liquid fraction of the effluent from at least one chimney tray in the tank to a fractionation section or the bottom section of the tank, and withdrawing from a top section of the tank at least a portion of the vapour fraction, the vapour fraction comprising acetic acid, the vapour fraction having been passed from the bottom section through the fractionation section, and then through one or more chimneys of the at least one chimney tray, and then through the spray section, and then through the porous demister surface of the demister section.

Trays having increased capacity and efficiency are described. The trays have a deck, and downcomers extending through the deck. There are a plurality of bubble promoters on the deck. Each bubble promoter defines a zone on the deck, and the zone has an opening in the deck. The opening is positioned adjacent to a solid support for the tray. The bubble promoters provide areas through which vapor can pass, turning blocked areas of the tray into active areas. Mass transfer columns containing the trays are also described.

A vapor-liquid contact tray apparatus includes a tray having a plurality of apertures for passage of fluid through the tray. The apertures are arranged in a first group of three adjacent rows extending substantially parallel to a main liquid flow path of the tray. Apertures of the middle row are offset along the main liquid flow path on the tray from adjacent apertures of the other two rows to form a triangular pattern of adjacent apertures across the three adjacent rows. The apertures have a length and a width, each length is oriented substantially parallel to its row and each width is oriented substantially perpendicular to its row. Centers of adjacent apertures within each row are separated by a first spacing which is equal to or between 2.5 and 4.5 times the average length of the apertures in that row. Adjacent rows are separated by a second spacing which is equal to or between 1.5 and 2.5 times the average width of the apertures of the adjacent rows.

A vapor-liquid contact tray apparatus includes a tray having a plurality of apertures for passage of fluid through the tray. The apertures are arranged in a first group of three adjacent rows extending substantially parallel to a main liquid flow path of the tray. Apertures of the middle row are offset along the main liquid flow path on the tray from adjacent apertures of the other two rows to form a triangular pattern of adjacent apertures across the three adjacent rows. The apertures have a length and a width, each length is oriented substantially parallel to its row and each width is oriented substantially perpendicular to its row. Centers of adjacent apertures within each row are separated by a first spacing which is equal to or between 2.5 and 4.5 times the average length of the apertures in that row. Adjacent rows are separated by a second spacing which is equal to or between 1.5 and 2.5 times the average width of the apertures of the adjacent rows.

A system and method for reducing a vapor temperature in a packed distillation column. Liquid is collected from a packed section of the packed distillation column in a liquid collector disposed below the packed section. A super-heated vapor is distributed from a vapor feed disposed below the packed section such that the super-heated vapor contacts the liquid of the liquid collector and reduces a temperature of the super-heated vapor.

A system and method for reducing a vapor temperature in a packed distillation column. Liquid is collected from a packed section of the packed distillation column in a liquid collector disposed below the packed section. A super-heated vapor is distributed from a vapor feed disposed below the packed section such that the super-heated vapor contacts the liquid of the liquid collector and reduces a temperature of the super-heated vapor.

A reactor for the synthesis of urea comprising a vertical shell and perforated baffles or trays (3) arranged to define compartments of the reactor, wherein each baffle comprises an array of individual perforated tiles (10) wherein each tile (101) comprises side walls (101A-101D) and a top face (101F), the side walls having first perforations for the liquid and said top face having second perforations for the gas, wherein said second perforations are smaller than said first perforations, and the tiles are distributed over the baffle with a two-dimensional pattern where adjacent tiles are separated by gaps (17).

A fluid contact tray (10) for a fractionation column (1), in particular a vapor-liquid contact tray suitable for the use in an offshore fractionation column, comprises: •a tray deck (12) comprising an active mass transfer surface (20) suitable for contacting two fluids (l, g) of different densities, wherein the active mass transfer surface (20) comprises one or more orifices (18) for the passage of a fluid/gas (g), and wherein at least two at least partially radially extending separation walls (22-1, 22-2, 22-3, 22-4) and/or at least one separation weir (42) are arranged on the active mass transfer surface (20), which divides the active mass transfer surface (20) into at least two sections (24-1, 24-2, 24-3, 24-4), •an annular channel (26) suitable for collecting fluids/liquids (l), which is arranged at the peripheral area of the active mass transfer surface (20) and at least partially embraces the mass transfer surface (20), •a central downcomer (34) for collecting and discharging a fluid/liquid (l) from the annular channel (26), wherein the central downcomer (34) has the form of a hollow body with an opening (36) in the bottom section thereof being suitable for the distribution of liquid vertically downwardly, and wherein the central downcomer (34) is non-rotatably fixed at the fluid contact tray (10), and •at least one conducting means (40) for transferring fluid collected in the annular channel (26) from the annular channel (26) to the central downcomer (34). This fluid contact tray (10) is in particular useable for offshore applications, such as for a fractionation column located on a FLNG or FPSO vessel.

An air stripper apparatus is disclosed which incorporates a plurality of trays that are removably supported within a cabinet. A plurality of downcomers are also fixedly disposed within the cabinet, rather than on the trays. Removing the downcomer from each tray enables a simpler, lighter and easier to clean tray to be constructed.