A plant for preparing a purified isomeric methylene diphenyl diisocyanate monomer from a mixture of different isomeric monomers is disclosed herein. The plant can comprise a distillation apparatus, which comprises: a) a distillation column including a structured packing, b) a source for a mixture of different isomeric methylene diphenyl diisocyanate monomers, c) an evaporator, d) an overhead vapor condenser, e) optionally, an overhead vacuum system and f) a flow-controlled reflux system. The overhead vapor condenser comprises a shell and tube arrangement and is embodied so as to directly subcool the condensate to less than 47° C. The flow-controlled reflux system comprises a heater, which is embodied so as to reheat a partial stream of the condensate formed in the overhead vapor condenser up to 190° C.

A high capacity and high efficiency co-current and cross-flow vapor-liquid contacting apparatus and process is useful in distillation columns and other vapor-liquid contacting processes. The apparatus is characterized by an arrangement of offset contacting modules in horizontal stages. The modules define a co-current contacting volume and in an exemplary configuration the modules include a liquid distributor and a demister. Half modules comprise downcomers against the shell of the vessel for transporting liquid to the subjacent stage.

A method for purifying an N-(-alkoxyethyl)formamide contained in a mixture thereof with a plurality of distillation columns, the plurality of distillation columns being arranged serially, the method including condensing a distillate from the second or any later-stage distillation column to obtain a condensate and returning at least some of the condensate to the preceding distillation column.

A method for purifying an N-(-alkoxyethyl)formamide contained in a mixture thereof with a plurality of distillation columns, the plurality of distillation columns being arranged serially, the method including condensing a distillate from the second or any later-stage distillation column to obtain a condensate and returning at least some of the condensate to the preceding distillation column.

A process and apparatus for hydrocracking a hydrocarbon stream and with heat integration between two stripping columns. Both stripping columns use a reboiler for heat input to avoid steam recovery and dew point issues in the overhead. A hot stripped stream can provide heat to the cold stripping column by heat exchange. Additionally, as few as two heaters that rely on external utilities may be required for reboiling fractionator column bottoms.

A process and apparatus for hydrocracking a hydrocarbon stream and with heat integration between two stripping columns. Both stripping columns use a reboiler for heat input to avoid steam recovery and dew point issues in the overhead. A hot stripped stream can provide heat to the cold stripping column by heat exchange. Additionally, as few as two heaters that rely on external utilities may be required for reboiling fractionator column bottoms.

An apparatus for mass transfer between a liquid and a gas inside a rotor having a packing. The liquid is introduced at a center of the rotor and driven outward through the packing by centrifugal force generated by rotation of the rotor, and the gas surrounding the rotor is forced inward through the rotor by a pressure of the gas, counter to the liquid flow in the rotor. The packing inside the rotor is divided into individual packing segments that together form a circular disk. Each circular ring segment is formed by at least one structured packing formed of a plurality of superimposed woven, knitted, mesh or lattice structured surfaces composed of metal, in particular sheet-metal strips, or plastic or glass fibers, to which the axis of rotation of the rotor runs perpendicular.

An apparatus for mass transfer between a liquid and a gas inside a rotor having a packing. The liquid is introduced at a center of the rotor and driven outward through the packing by centrifugal force generated by rotation of the rotor, and the gas surrounding the rotor is forced inward through the rotor by a pressure of the gas, counter to the liquid flow in the rotor. The packing inside the rotor is divided into individual packing segments that together form a circular disk. Each circular ring segment is formed by at least one structured packing formed of a plurality of superimposed woven, knitted, mesh or lattice structured surfaces composed of metal, in particular sheet-metal strips, or plastic or glass fibers, to which the axis of rotation of the rotor runs perpendicular.

A scrubber for cleaning a gas comprises a casing extending along a longitudinal central axis and enclosing a scrubbing chamber. The casing has a gas inlet and a gas outlet. The casing is configured to permit flow of the gas through the scrubbing chamber in a flow direction from the gas inlet to the gas outlet. A deflector device in the scrubbing chamber between the gas inlet and outlet forms a gas passage between the deflector device and the casing. The deflector device comprises an upstream surface facing the gas inlet. A spraying nozzle is configured to spray a scrubbing liquid into the scrubbing chamber and the gas flow. A separation device comprises a shield element and is arranged between the upstream surface of the deflector device and the gas inlet. The shield element shields the upstream surface from the gas flow and is perforated by a plurality of holes.

The invention concerns an apparatus (10) for separation of components with different volatility in a mixed fluid, said apparatus (10) comprising: a first heat exchanging unit (100) provided with first and second flow path structures (131, 132) forming separate flow paths for a first and a second fluid flow through the first heat-exchanging unit (100); an inlet (118) for feeding the mixed fluid to the apparatus (10); an inlet (119) for feeding steam to the apparatus (10); an arrangement for feeding a cooling medium through the apparatus (10), wherein said arrangement comprises at least one cooling medium inlet (105, 106, 107, 108). The invention is characterized in that the apparatus (10) comprises a second heat-exchanging unit (200) provided with third and fourth flow path structures (233, 234) forming separate flow paths for a first and a second fluid flow through the second heat-exchanging unit (200), wherein the cooling medium arrangement comprises at least one cooling medium inlet (205, 206, 207, 208) arranged in fluid communication with the fourth flow path structure (234) and wherein the first and third flow path structures (131, 233) are arranged in fluid communication with each other.