Abstract: The invention relates to a process for purification of a stream containing a cyclic ester of an alpha-hydroxycarboxylic acid of formula (I), wherein each R independently represents hydrogen or an aliphatic hydrocarbon having 1 to 6 carbon atoms comprising the steps of: (a) separating the cyclic ester-containing stream into one or more cyclic ester-containing vapor fractions and one or more cyclic ester-containing liquid fractions; (b) condensing a cyclic ester-containing vaporized fraction as obtained in step (a) to obtain a cyclic ester-containing condensate; (c) subjecting at least part of the cyclic ester-containing condensate as obtained in step (b) to melt crystallization to obtain a purified cyclic ester-containing stream and a residue stream; and (d) recovering the purified cyclic ester-containing stream as obtained in step (c). The invention further relates to an apparatus suitable for carrying out the present process.

Abstract: An evaporator (1) adapted for a counter-current flow of at least one liquid and one vapor therein is disclosed. The evaporator (1) comprises an evaporator sub-unit (70), an internal sub-unit (90) having a surface (92), a heat exchanger sub-unit (100), and a condenser sub-unit (110), all in communication with one another and contained within one common vessel (12), wherein the internal sub-unit (90) is located above the evaporator sub-unit (70), the heat exchanger sub-unit (100) is located above the evaporator sub-unit (70), and the condenser sub-unit (110) is located above the heat exchanger sub-unit (100) and the internal sub-unit (90). The present invention further relates to a process to separate components using the evaporator (1) and also to the use of the evaporator (1) or the process in the purification and/or concentration of a thermally-sensitive compound and/or in the removal of a solvent.

Abstract: A method for stabilizing a condensed phase composition in a process of manufacturing a polyester from cyclic ester monomer comprising the steps of devolatilizing a reaction mixture, which contains i) at least one polymerizable cyclic ester, ii) at least one catalyst and optionally at least one initiator, to produce a vapor stream and a molten residue, wherein the vapor stream includes mainly i) the at least one polymerizable cyclic ester and ii) the at least one catalyst and/or the at least one initiator and/or a reaction product or a residue of the at least one catalyst and/or the at least one initiator and condensing the vapor stream to form the condensed phase composition, wherein at least one polymerization inhibitor is added as stabilizer to the reaction mixture and/or to the condensed phase composition in an amount so that the degree of conversion of the polymerizable cyclic ester in the condensed phase composition is not more than 15%, wherein the degree of conversion is 100?(c0?CF)/c0, wherein c0 is t

Abstract: A process for the separation of a substance from a liquid feed mixture and for the purification of the substance by fractional layer crystallization, wherein the liquid feed mixture comprises the substance to be separated and purified in a concentration of less than 50% by weight, which comprises the subsequent steps in the given order: (a) feeding the liquid feed mixture into a crystallization zone, in which at least one surface is provided, so that at least a part of the surface contacts the liquid feed mixture, (b) cooling the at least one surface of the crystallization zone to a temperature below the equilibrium freezing temperature of the liquid feed mixture so that a crystal layer enriched in the substance to be separated and purified is deposited on the at least one cooled surface, whereby a mother liquid having a lower concentration of the substance to be separated and purified than the liquid feed mixture is formed from the liquid feed mixture, (c) removing at least a portion of the mother liquid fro

Abstract: A hybrid Contact tray for a mass transfer column is provided. The tray has a deck for passage of liquid along a liquid flow path thereon. The deck also has a plurality of orifices for passage of ascending vapor through the tray deck. The contact tray includes a cross-current vapor-liquid mixing section having a first portion of the plurality of orifices and a co-current vapor-liquid mixing section having at least one co-current mixing device associated with a second portion of the plurality of orifices. The co-current mixing device includes a conduit having: a vapor inlet in fluid communication with one or more of the second portion of orifices; a froth inlet in fluid communication with the liquid flow path; a fluid outlet; and a packing material within a co-current flow path of vapor and liquid within the conduit disposed after the vapor and froth inlets and before the fluid outlet.

Abstract: A hybrid contact tray for a mass transfer column is provided. The contact tray includes a tray deck for passage of liquid along a liquid flow path thereon. The tray deck has a plurality of orifices for passage of ascending vapor through the tray deck, a cross-current vapor-liquid mixing section having a first portion of the plurality of orifices, and a co-current vapor-liquid mixing section including at least one co-current mixing device associated with a second portion of the plurality of orifices. The tray deck also has features capable of altering liquid head levels with respect to the plurality of orifices such that the liquid head level within the co-current vapor-liquid mixing section is greater than the liquid head level within the cross-current vapor-liquid mixing section.

Abstract: The present invention relates to a method for fractionating a crude mixture comprising at least one oil and at least one wax, which comprises the following steps: (a) mixing the crude mixture with a solvent to obtain a crude solvent-mixture, (b) carrying out at least one crystallization stage with the solvent-mixture obtained in step (a) to prepare a first fraction containing dewaxed oil and a second fraction containing slack wax, (c) carrying out at least one crystallization stage with the second fraction obtained in step (b) in a layer crystallizer, wherein to the second fraction prior to the crystallization in step (c) no solvent or at most 100% by weight of solvent relative to the weight of the second fraction are added, to prepare a third fraction containing hard wax having an oil content of at most 1.5% by weight and a fourth fraction containing soft wax having an oil content of more than 1.

Abstract: A liquid mixing collector includes first and second sump zones, a first and optionally a second liquid collection region, first and second interspersed sets of spaced apart liquid collection channels positioned in the first liquid collection region, the first and second sets of collection channels being associated with the first and second respective sump zones, wherein adjacent liquid collection channel sets are vertically displaced in parallel horizontal planes. The invention also relates to the process of using the collector within a heat or mass transfer column.

Abstract: A liquid-liquid extraction system (1) adapted for the flow of two or more liquids therein is disclosed. The system comprises a mixer settler sub-system (100) and a counter-current liquid-liquid extraction column (200). The sub-system (100) comprises one or more mixer settlers (110) connected in series, and the column (200) comprises either a mixing section (260) comprising an agitation means (261) and/or a static section (280) comprising an internal (281). The first outlet (131) of the mixer settler sub-system (100) is in fluid communication with the first inlet (221) of the column (200) and the second inlet (112) of the mixer settler sub-system (100) is in fluid communication with the second inlet (222) of the counter-current liquid-liquid extraction column (200). The invention further relates to a counter-current liquid-liquid extraction process for using said system 1.

Abstract: 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.

Abstract: A fractionation tray includes a manway unit positioned to cover a manway opening in the fractionation tray. The manway opening is framed by one or more fractionation tray panels having apertures therethrough adjacent to the manway opening. The manway unit includes a first manway panel having: perforations for the passage of fluid; first and second opposing side edges and two opposing end edges; and finger elements extending from the second side edge. The finger elements of the second side edge are received within the apertures adjacent to a first side of the manway opening. The manway unit is configured to open and close by rotation of the finger elements within the apertures.

Abstract: 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

Abstract: A process and an apparatus for the purification of a crude acrylic acid composition containing maleic anhydride as an impurity comprising the following steps: (a) carrying out at least one dynamic melt crystallization stage (14, 14a, 14b, 14c, 14d) with the crude acrylic acid composition to prepare a first purified acrylic acid composition and a first residue containing at least 3.5% by weight maleic anhydride, (b) adding a solvent (26) which is capable of dissolving maleic anhydride to the first residue in an amount that the weight ratio of the solvent to the maleic anhydride is 0.3 or more to prepare a ratio-adjusted residue and (c) carrying out at least one further dynamic melt crystallization stage and/or at least one static melt crystallization stage (18, 18a, 18b) with the ratio-adjusted residue to prepare a second purified acrylic acid composition and a second residue.

Abstract: A continuous through-flow settling vessel for adaptive separation of a mixture from gas and/or oil exploration or production, said mixture comprising a varying mixture of liquid and gaseous phases, wherein the vessel is provided with: an inlet for a mixture, and a gas outlet, a water outlet and an oil outlet, the outlets being provided distant from the inlet, and the oil outlet being downstream of the water outlet, a weir downstream of the water outlet and upstream of the oil outlet, which weir functions as a barrier to a free through-flow in the vessel of the liquid phase which comprises a water phase and an oil phase, which phases are separated from each other by settling, the weir having a height lower than the gas outlet, and wherein the vessel is additionally provided with:—an oil draining means capable of controllably draining oil phase from the vessel upstream of the weir, said means being provided at a level below the weir height and above the water phase that is present during operation of the vessel

Abstract: The invention relates to a vane diffuser for separating a gas/liquid/particulate-mixture flow in a gas phase fraction and a liquid/particulate phase fraction, comprising: a distribution chamber holding a plurality of curved vanes and an inlet for the gas/liquid/particulate-mixture wherein the vane diffuser also comprises a cyclone pre-separator located before the distribution chamber. The invention also relates to a method for separating a gas/liquid/particulate-mixture.

Abstract: A polyester polymer composition having a polyester polymer with furanic units as well as a process to prepare this polyester polymer composition are herein described. The process includes the step of reacting a cyclic polyester oligomer in the presence of a catalyst in a ring-opening polymerization reaction with a reaction temperature and a reaction time sufficient to yield a polyester polymer having furanic units. The present invention further provides a method of use of this polyester polymer composition in extrusion, injection molding, or blow molding.

Abstract: A counter-current liquid-liquid extraction column (1) adapted for the flow of two or more liquids (2) therein is disclosed. The column comprises within one common vessel (3): a first inlet (41) for a first liquid feed stream (51), a second inlet (42) for a second liquid feed stream (52), a first outlet (61) for a product stream (71), a second outlet (62) for a byproduct stream (72), a mixing section (8) comprising an agitation means (9), a static section (10) comprising a packing (11), optionally a collector (12) and/or distributor (13), characterized in that within the common vessel (3) are only one mixing section (8) and only either one or two static sections (10). The invention further relates to a process for using said column. The present invention further relates also to the use of the column or process in removing aromatic compounds from organic streams, in treating an oil stream of a refinery, or in a liquid-liquid extraction process.

Abstract: The invention relates to a device for electrostatic coalescence of liquid particles in a flowing fluid mixture, comprising: a tube having an feed opening located at the front side of the tube and a discharge opening located on the opposite side of the tube and a least one arrangement with flow guide vanes arranged in the tube, positioned in between the opened infeed side and an opposite opened outfeed side, for reducing the turbulence or for imparting a rotating movement to the fluid mixture flowing through the tube. The invention also relates to a method for electrostatic coalescence of liquid particles in a flowing fluid mixture.

Abstract: The present invention relates to a method for reducing the transition time and/or the polymer waste being out of the specification during the change from a first polymer grade to a second polymer grade in a continuous polymerization process conducted in a polymerization plant, wherein the polymerization plant comprises at least one back-mixing reactor, at least one monomer and at least one processing agent selected from the group consisting of catalysts, co-catalysts, polymerization initiators, comonomers, chain-transfer agents, branching agents, solvents and arbitrary combinations of two or more of the aforementioned agents are added before and/or during the polymerization process into the at least one back-mixing reactor, wherein the concentration of one or more of the at least one added processing agent in the feed introduced into the at least one back-mixing reactor is varied as a function of time from a first value associated with the first polymer grade to a final value associated with the second polyme

Abstract: A process of manufacturing a polyester from cyclic ester monomer comprises the steps of: a) providing a cyclic ester, b) polymerizing the cyclic ester in the presence of a catalyst and optionally an initiator in a reactor to form a reaction mixture comprising polyester and unreacted cyclic ester, wherein after the polymerization at least one polymerization inhibitor is added to the reaction mixture, wherein the polymerization inhibitor is selected from the group consisting of monoimines, diimines, mono alkyl phosphates according to the formula RPO4H2, wherein R is a C6-16 linear, branched or cyclic alkyl group, di alkyl phosphates according to the formula R2PO4H, wherein each R is independently a C6-16 linear, branched or cyclic alkyl group or a combination thereof, and phosphate esters according to the general formula (I) wherein at least one of R?, R? and R?? has the general structure as in general formula (II) wherein n>0 and Q is independently a C1-16 linear, branched or substituted alkyl group, and R