Abstract: The invention is generally directed to an evaporative humidifier having a water distribution system capable of quietly maintaining a continuously saturated wicking element through the use of a pump and water distribution troughs that allow water to be continuously flushed onto the tops of the wicking elements such that greater humidification of the air is achieved and the life of the wicking elements are extended.

Abstract: A collector is used to collect and mix liquid from an overlying zone in a mass transfer column in which fluid streams are processed, such as to obtain fractionation products. The collector has two or more liquid collection regions and two or more sumps positioned about the perimeter of the liquid collection regions. A plurality of channels and deflectors are spaced apart within each liquid collection region and vapor passages are formed in the spacings between adjacent channels. The deflectors direct descending liquid into the channels and shield the vapor passages from the descending liquid. The channels within each liquid collection region are arranged into interspersed sets, with one set of channels preferentially directing collected liquid into one sump and another set of channels preferentially directing collected liquid into another sump.

Abstract: A column tray assembly includes a tray having passages formed therein. The tray is a multifunction tray and is configured to receiving appropriate superstructures which can be selected according to the respective use of the assembly. Superstructures which communicate with the passages are mounted to the tray. The superstructures have gas penetration holes embedded in such way that, when the superstructures are mounted to the tray, the orifices of the gas penetration holes extend in a perpendicular manner in relation to the tray. The tray and the superstructures are formed from the same or different corrosion-resistant materials or combination of materials. The tray may also be provided with smaller holes for the discharge of liquid, into which holes distributor cups, or the like are inserted. These smaller holes may be closed for specific purposes.

Abstract: The invention is generally directed to an evaporative humidifier having a water distribution system capable of quietly maintaining a continuously saturated wicking element through the use of a pump and water distribution troughs that allow water to be continuously flushed onto the tops of the wicking elements such that greater humidification of the air is achieved and the life of the wicking elements are extended.

Abstract: Vapor and liquid passing downward through a vessel are brought into contact within a plurality of distributor assemblies arranged across a horizontal distribution tray located within the vessel. The distributor assemblies have fluid flow paths with different resistances to fluid flow, as by having vapor inlets of at least two different sizes, with the differently sized inlets being located on different assemblies or on different upflow channels of the same assembly. This provides different vapor flow rates and liquid flow rates in different upflow channels. The invention improves the uniformity of liquid distribution over the cross section of the vessel despite elevational differences in liquid levels on the distribution tray or changes in the vapor and or liquid flow rates through the reactor.

Abstract: An apparatus for distributing a liquid in an exchange column includes a plate and at least one elongated internal baffle. The plate has at least one elongated channel, which has a first longitudinal axis, a bottom, and at least one aperture in the bottom. At least a substantial portion of the internal baffle, which has a second longitudinal axis substantially parallel to the first longitudinal axis, is disposed in the channel.

Abstract: A liquid collector for use in a vapor liquid contacting vessel such as a distillation column having bolted or otherwise fastened components wherein liquid leakage is ameliorated by a collector tray divided into three overlapping levels including a center sump, deck plates and riser hats.

Abstract: A water spreader arrangement for use in an evaporative air cooler in which the spreader includes an inlet leading to generally vertical projections disposed over several levels. The projections are adapted to divide a single stream of water entering the inlet into many outlet streams, all of which have a predetermined ratio of flow rates. The outlet streams can be fed to an evaporative pad of an evaporative cooler. In a preferred form, the outlet streams have substantially the same flow rate. Preferably, a cooler incorporating this water spreader arrangement would include several spreaders around the upper periphery of the evaporative pads.

Abstract: Liquid distributors collect liquid falling out of the spout group at the ends of a downcomer of a fractionation tray. The devices then distribute the liquid against the wall of the column or onto the decking of the next lower tray so to cause uniform liquid flows across the terminal decking section of the next lower multiple downcomer tray. The apparatus improves the liquid flow path on the terminal decking section of the tray, thus increasing the overall efficiency of the tray.

Abstract: A packing for a mass transfer column for absorption, desorption, rectification or extraction processes, includes a packing bed having a packing element, a tubular shrink film shrunk onto at least a portion of a periphery of the packing element, and a baffle arranged at the periphery of the packing element to prevent a wall effect in the column. The baffle has a conical edge which extends outwardly with respect to the shrink film and is made of plastic.

Abstract: A mass transfer column is provided with a liquid distributor that distributes liquid to an underlying mass transfer bed containing one or more random, grid or structured packing elements. The liquid distributor includes a plurality of elongated troughs that are spaced apart and extend across the column. A plurality of liquid discharge holes are positioned in side walls of the trough and are located in one or more preselected planes that are preferably spaced above a floor of the trough. Splash baffles are spaced outwardly from the trough side walls and include upper portions that are positioned to receive liquid exiting the troughs through the discharge holes. Lower portions of the splash baffles form a constricted discharge outlet in a plane below the trough for delivering liquid from the splash baffles to the underlying mass transfer bed.

Abstract: When carrying out a liquid-phase reaction by using a heterogeneous catalyst, the separation of the heterogeneous catalyst and the reaction liquid is carried out certainly and effectively. A reaction method involves carrying out a reaction in liquid phase by using a heterogeneous catalyst particle 30 in a reactor 10, and comprises the steps of: (a) allowing a reaction liquid 40 supplied into the reactor 10 from such as a supplying inlet 12 to react in the presence of the heterogeneous catalyst particle 30, and (b) passing the resultant reaction liquid 40 containing the heterogeneous catalyst particle 30 through a line screen 20 having an opening width where the heterogeneous catalyst particle 30 is not allowed to pass substantially, and then extracting the reaction liquid 40 separated from the heterogeneous catalyst particle 30 from the reactor 10 by way of such as an extracting outlet 14.

Abstract: The invention relates to a wash column for material and/or energy exchange between media, especially between a liquid trickling down and a gas or a lighter liquid rising in a counter-current. The invention especially relates to a novel structural packing that comprises liquid guide elements (19) in the form of wires or threads that form substantially rhomboid masses with vertical axes in imaginary surfaces (21) and that surround, for example in a polygonal grid, substantially free, vertical flow channels (22) for the counter-flowing gas. The nodes (18) of the liquid guide elements (19) are located at the respective points of intersection of a horizontal cross-section grid. The distance between the guide elements or the size of the meshes is chosen such that the liquid does not form film curtains and flows off only in defined flows, linearly along the guide elements (19).

Abstract: A counterflow column that includes a liquid distributor including a plurality of tubular or trough-like distributor members. The distributor members are arranged in a column above a packing such that a plurality of partial flows develop in an upwardly flowing gas at the level of the distributor members. Stagnation zones are present between the packing and the distributor members. Through screen-off structure, not required per se for a liquid output, the stagnation zones and/or the flow of a liquid to be distributed are influenced such that a liquid, after emerging from the distributor members and prior to entry into the packing, traverses in free fall through the stagnation zones, and where appropriate also further regions, in which the gas flow is largely free of horizontal velocity components. The gas flow may also be influenced by a suitable shaping of the distributor members.

Abstract: A humidifier features a two piece reversible housing which is snap fit together for holding a water panel assembly and a water feed tube to supply water to a water distribution structure disposed on top of the water panel assembly. The water panel assembly is provided with an overflow arrangement for controlling any overflow of water in the water distribution structure.

Abstract: The liquid distributor (2) for columns (1) comprises at least one tub shaped or tubular part (3) of a rigid material. Outflow elements (4) of yielding, in particular elastomeric material are tightly inserted into apertures (30) of the tub shaped or tubular part. A liquid (6) to be distributed can flow off in each case through at least one opening (40) in the outflow element. This opening has a precisely predeterminable geometry.

Abstract: The invention relates to a device for producing a gas mixture consisting of HMDSO and oxygen, whereby process gas is produced. In order to be able to continuously produce a large volume of process gas using such a device and to be able to withdraw the same at practical processable temperatures, the invention provides that a number of filling packages (2) are stacked in an elongated essentially vertical column (1) that can be cooled. In addition, an inlet tube (3), which is inserted into the column (1) from the exterior, and a gas outlet connection (6), which leads to the exterior, are secured in the upper area of said column (1). Devices (26) are also provided for measuring the temperature, the pressure and the amount of the exiting gas mixture. In addition, a distribution cup (29) which spans the cross-section of the column (1) and which is provided with gas flow-through openings (38) is placed underneath the inner discharge end (4) of the inlet tube (3).

Abstract: An apparatus for distributing a liquid in an exchange column includes a plate and at least one elongated internal baffle. The plate has at least one elongated channel, which has a first longitudinal axis, a bottom, and at least one aperture in the bottom. At least a substantial portion of the internal baffle, which has a second longitudinal axis substantially parallel to the first longitudinal axis, is disposed in the channel.

Abstract: A cooler pad frame for an evaporative cooler includes an outer panel and an inner panel defining a pad space for holding a pad element. The outer panel has a plurality of louvered openings for allowing a stream of air to flow through the outer panel and into the pad element, and the inner panel has a plurality of louvered opening for allowing the stream of air to flow out of the pad element and through the inner panel. The inner panel and outer panel louvered openings have louvers projecting at an angle toward the bottom of the pad frame and inward toward the pad space. In an evaporative cooler, the pad frame is mounted to the cooler frame for holding the pad element between an air inlet and an air outlet such that the stream of air flowing through the inlet passes through the pad. A method for reducing entrainment in an evaporative cooler includes disposing a pad element in an air stream, disposing a louvered inner panel at a position downstream of the pad element and distributing water over the pad element.

Abstract: The invention relates to a liquid distributor for packed and/or filled columns, comprising individual, in particular horizontal layers involved in heat and/or material exchange. At least one layer of the column has a flooding, in particular for obtaining an increased density and for creating an accumulation of liquid and a specific surface for distributing the liquid. Said surface is greater than the surface of the overlying and underlying layers by a factor of 1.5 to 10, preferably by a factor of 2 to 3.

Abstract: The guide member for a liquid jet to be deflected allows a liquid after flowing out of a container to be deflected onto a target which is located below the container. The deflecting takes place by means of a shaped material plate which is arranged ahead of an outlet opening of the container and which reshapes and further conducts the jet in such a manner that the liquid is conveyed to the target at a lower end of the shaped material plate. At the location ahead of the outlet opening, where the liquid jet is incident onto the shaped material plate, a first and a second piece of surface of the material plate form a mouth region in which the first piece of surface deflects the liquid transversely with respect to the vertical, whereas the second piece of surface is provided as a catcher for squirts. The first piece of surface merges into a channel in which the liquid is guided downwards. In this the wall of the second piece of surface divides the channel off from the mouth region.

Abstract: A mixture containing oxygen is introduced into a distillation column (1); an intermediate stream, substantially free from impurities heavier than oxygen, is withdrawn (at 17) at a level of the column located above the point (4) of introduction of the air, the point (22) of withdrawal being separated from this point (4) of introduction by a distillation section (6), particularly with packing; the stream withdrawn (at 17) is sent to an oxygen purification column (2), and a reflux liquid is distributed over the section (6) by a distributor (9). A predetermined non-uniformity of the distribution of the reflux liquid over the upper surface (8) of the section (6) is effected in at least one localized region (23) of this surface.

Abstract: The apparatus for the collection and distribution of liquid in a column having at least one lamella collector and a distributor outflow system which is arranged below it. A side passage is contained in the or in each lamella collector and liquid outflow openings are arranged in a combination, as a result of which a hydrodynamic equalization for a liquid to be distributed results.

Abstract: A flow distributor is provided for distributing liquid onto a packed bed of a process column. The distributor includes an elongated liquid trough having first and second laterally spaced, longitudinally extending sidewalls and a longitudinally extending floor which extends between and interconnects the sidewalls. The sidewalls each have a plurality of holes therethrough, which holes are spaced apart longitudinally of the distributor. The distributor also includes a respective elongated liquid distributor drainpipe for each of the holes. Each pipe has first and second ends and a central internal liquid conducting passageway extending therethrough between its ends. Each pipe also has a first segment adjacent its first end and a second segment spaced longitudinally of the pipe from the first end. The segments are angularly disposed relative to one another. The distributor also includes a respective connector assembly for each of the pipes.

Abstract: The invention comprises a water distribution mechanism for an evaporative air conditioner that alleviates splashing of water out of that mechanism. Further, the invention alleviates the problem of water running horizontally along a distribution edge of a water distribution mechanism to drip off at the lowest point. To compensate for the splashing problem, the invention comprises a structure that requires the water exiting the water distribution mechanism strike at least one surface of the water distribution mechanism on its way down. To compensate for the problem of water running horizontally because of sags and the like, the invention comprises a plurality of teeth along the bottom edge of the water distribution bonnet that therefore forces the water to drip rather than to move horizontally.

Abstract: A scrubber for removing soluble materials from harmful gaseous effluents with high efficiency and safety is disclosed. By using twice mixes of the scrubbing liquid and the harmful gaseous effluent, the scrubber meets the standards of environment protection. The scrubber of this invention also prevents the problems of factory safety presenting in the conventional fume scrubber. Owing to the high efficiency of the mixing of the harmful gaseous effluent and the scrubbing liquid, the production facilities or processing units need not stop operating once the supply of the scrubbing liquid terminates.

Abstract: A humidifier features a two piece reversible housing which is snap fit together for holding a water panel assembly and a water feed tube to supply water to a water distribution structure disposed on top of the water panel assembly. The water panel assembly is provided with an overflow arrangement for controlling any overflow of water in the water distribution structure.

Abstract: A distillation column and method in which a plurality of beds of structured packing are provided within a column shell and are configured to contact liquid and vapor phases of the mixture to be distilled. At least one liquid redistributor is located between the beds of structured packing to redistribute the liquid of the liquid phase and an annular collector is located above the liquid distributor to direct liquid to the liquid distributor. The annular collector acs as a constriction to produce a central flow of the vapor phase which can result in decreased performance of overlying beds of structured packing. In order to overcome this potential problem, a truncated bed of structured packing is provided directly above the annular collector to promote a more uniform distribution of such central vapor flow in a transverse direction of the column shell.

Abstract: A mass transfer column is provided with a liquid distributor that distributes liquid to an underlying mass transfer bed containing one or more random, grid or structured packing elements. The liquid distributor includes a plurality of elongated troughs that are spaced apart and extend across the column. A plurality of liquid discharge holes are positioned in side walls of the trough and are located in one or more preselected planes that are preferably spaced above a floor of the trough. Splash baffles are spaced outwardly from the trough side walls and include upper portions that are positioned to receive liquid exiting the troughs through the discharge holes. Lower portions of the splash baffles form a constricted discharge outlet in a plane below the trough for delivering liquid from the splash baffles to the underlying mass transfer bed.

Abstract: The apparatus for the collection and distribution of liquid in a column comprises at least one lamella collector (200) and a distributor outflow system (300) which is arranged below it. A side passage (210) is contained in the or in each lamella collector and liquid outflow openings (214, 216, 332) are arranged in a combination, as a result of which a hydrodynamic equalisation for a liquid to be distributed results.

Abstract: This distributor (1) includes: a primary distributor (3) which delimits a closed volume provided with liquid predistribution openings (8) which open into the column; a device for feeding the primary distributor (3) with liquid under a pressure very much greater than the internal pressure of the column; and a secondary distributor (4) which occupies substantially the entire cross-section of the column, which includes a gas overhead in communication with the internal space of the column and which is subdivided by partitions (13, 17) into a plurality of compartments (16), each of which receives liquid originating from at least one of the said openings (8) of the primary distributor (3), this secondary distributor (4) having a bottom (9) provided with orifices (12) for fine distribution of the liquid over virtually the entire cross-section of the column, the number of these orifices being very much greater than the number of openings (8) of the primary distributor.

Abstract: There is provided a feed distributor for feeding liquid to a liquid distributor. The feed distributor has an elongated body sized to extend across the liquid distributor and an inlet defined in the one of the ends thereof. One or more passageways are provided within the body extending between the ends of the body. Each passageway has an elongated outlet configured to discharge the liquid across the liquid distributor. Each passageway has a taper configured to promote a constant liquid velocity within the passageway. As a result, a uniform liquid distribution of the liquid out of the elongated outlet and therefore to the liquid distributor are promoted.

Abstract: Liquid distributors collect liquid falling out of the spout group at the ends of a downcomer of a fractionation tray. The devices then distribute the liquid against the wall of the column or onto the decking of the next lower tray so to cause uniform liquid flows across the terminal decking section of the next lower multiple downcomer tray. The apparatus improves the liquid flow path on the terminal decking section of the tray, thus increasing the overall efficiency of the tray.

Abstract: A quench zone mixing apparatus that occupies a low vertical height and has an improved mixing efficiency and fluid distribution across the catalyst surface includes a swirl chamber, a rough distribution network, and a distribution apparatus. In the swirl chamber, reactant fluid from a catalyst bed above is thoroughly mixed with a quench fluid by a swirling action. The mixed fluids exit the swirl chamber through an aperture to the rough distribution system where the fluids are radially distributed outward across the vessel to the distribution apparatus. The distribution apparatus includes a plate with a number of bubble caps and associated drip trays that multiply the liquid drip stream from the bubble caps to further symmetrically distribute the fluids across the catalyst surface. Alternatively, deflector baffles may be associated with the bubble caps to provide a wider and more uniform liquid distribution below the plate.

Abstract: A vapor-liquid contacting tower having a tray deck, at least one downcomer and a structure packing layer in the space under the vapor-liquid bubble contacting tray wherein the tray deck has an opening such that vapor ascends upward through the opening to come into contact with the liquid flowing across the tray deck to form a froth in which the vapor and the liquid on the tray deck creates cross-flow bubble contact and with the structural dimensions of the tray deck and downcomer providing for at least 90 vol % of the total liquid flowing across the tray deck flows downwardly through the downcomer to the adjacent deck.

Abstract: The column contains a base (1) between an upper and a lower filler body section (8). With this base, liquid (9) is collected from the upper section in a buffer chamber (3) and collected liquid is distributed onto the lower section (8). Flues (2) serve as passages for a gas transport through the buffer chamber. Outlet openings (6) of the buffer chamber are arranged in vertical walls (20) of the flues and guide members (4) for the liquid to be distributed are arranged ahead of the outlet openings. Each outlet opening and its associated guide member are formed in such a manner that the liquid is incident onto a deflection surface (41) of the guide member as a largely free jet (90) unimpeded by a back pressure. The flue cross-section which is available for the gas transport is decreased by the guide members by at most 20%.

Abstract: A flow distributor for distributing liquid onto a packed bed of a process column. The distributor includes an elongated liquid trough having first and second laterally spaced, longitudinally extending sidewalls and a longitudinally extending floor which extends between and interconnects the sidewalls. The sidewalls each have a plurality of holes therethrough, which holes are spaced apart longitudinally of said distributor. The distributor also includes a respective elongated liquid distributor drain pipe for each of said holes. Each pipe has first and second ends and a central internal liquid conducting passageway extending therethrough between its ends. Each pipe also has a first segment adjacent its first end and a second segment spaced longitudinally of the pipe from the first end. The segments are angularly disposed relative to one another.

Abstract: The flooding capacity of a fractionation tray (2) is increased by the addition of at least one layer of low surface area grids (3) above the inlet to the downcomers (6,12) located on the tray (2). The grids (3) extend upward for a distance equal to one to four times the depth of the downcomers. The grids may rest upon the top edge of the downcomers or on the tray decking between the top portions of the downcomer sidewalls.

Abstract: In a method for distilling (meth)acrylic acid and/or (meth)acrylic ester, the method has the step of uniformly distributing a supply liquid in a distillation tower over an entirety of a horizontal cross sectional area in the distillation tower. A distillation apparatus for distilling (meth)acrylic acid and/or (meth)acrylic ester in a distillation tower has a supply element for supplying the supply liquid into the distillation tower. The supply element is formed with at least two supply ports through which the liquid is supplied into the distillation tower.

Abstract: A liquid distributor for packing columns. The liquid distributor includes at least one tubular or trough-like distributor member including outlet openings for an output of liquid in the form of jets. Screens are arranged ahead of the outlet openings onto which the incident liquid jets are deformed to liquid films flowing off. The outlet openings screen the outlet openings against an upwardly flowing gas flow. In the event of a maximum output of liquid, the liquid jets are incident onto the screens at angles that are less than 60°, and even as much as less than 10°.

Abstract: This liquid distributor includes: a primary distributor (13) including liquid-distribution openings and delimiting N1 first compartments (22), each provided with liquid feed elements means (10, 11); and a secondary distributor (14), arranged under the primary distributor (13) and including a dish with openworked perforated bottom which occupies substantially the entire cross-section of the distillation column (2), this dish being subdivided by partitions (25) into N2 second compartments (24), with N2>N1.

Abstract: Internal members or baffles for material exchange columns have at least one packing bed. The packing bed has at least one first packing block and at least one correction element associated with the first packing block. The first packing block and its associated correction element produce different final distributions of liquid or systematic maldistributions. The systematic maldistribution in the liquid phase caused by the first packing block is largely corrected by the systematic maldistribution of the associated correction element. Such an arrangement makes possible enhanced separation efficiency or higher packing beds.

Abstract: An automatic flush water distribution system for use in an evaporative cooling system includes a water distribution pipe adapted to be connected to a source of pressurized water. The pipe has a plurality of water distribution ports formed therein and a vertical flush pipe is connected at a first end to the water distribution pipe in liquid communication therewith. The flush pipe includes a second lower end and contains at least one valve seat and at least one buoyant float valve located therein between the valve seat and the water distribution pipe.

Abstract: A dispersion device for spreading liquid over heat transfer surfaces. A tube shaped central element has guide elements in its interior which extend out of the central element's bottom end pointing away from the longitudinal axis of the central element channeling and dividing liquid flow into a pattern of liquid trickles.

Abstract: A liquid distributor for a packed liquid-vapor contact column includes a header tank; a liquid distribution plate having vapor riser passages and a multiplicity of discrete reservoir cells each having an aperture for flow of liquid therefrom into the column; and conduits for feeding liquid from the header tank into each cell. The liquid distribution plate preferably has a uniform criss-cross structure with alternating vapor riser passages and reservoir cells of identical shape and size. The conduits may have two or more sections each feeding a discrete group of reservoir cells from a location of the header tank at an elevation spaced from that of the other section(s). The distributor compensates for column sway or tilt when mounted on, for example, a ship.

Abstract: A gas-liquid dispersion device to be installed in a system in which a liquid flows forming a continuous phase and a gas flows upward includes a perforated plate which is so mounted as to interrupt a gas-liquid passage, in which a mixed phase of the gas and liquid is produced. A separated liquid-conducting channel extending from the perforated plate toward its gas inflow opening side is formed in such a way that a gas-liquid passage is divided into a liquid-conducting portion and a gas-dispersing portion. When the mixed phase of the gas and liquid is supplied to the gas-liquid dispersion device, a gas phase accumulates on the gas inflow opening side of the gas-liquid dispersion device and creates a gas pocket, whereby pulsation of gas and liquid flows can be prevented. As a result, the gas passes upward through individual through holes (excluding the liquid-conducting channel) made in the perforated plate while the liquid passes through the liquid-conducting channel in a stable manner.

Abstract: Device and application thereof for distributing a multiphase mixture having at least one gas phase including, e.g., hydrogen in part and at least one liquid phase, the mixture being in a downward flow through at least one bed of granular solids, the device including, at least one distributor plate located above one of the beds of granular solids at a distance "d", and several mixing channels of the liquid and gas phases of the mixture. Each of the channels has at least one upper passage section and at least one lower passage section allowing communication between the mixture formed in the mixing channels with a bed of granular solids. The mixing channels are provided on at least part of their height with one or more lateral passage sections, the upper passage section allowing the majority of the gas phase of the mixture to pass and the lateral passage sections allowing passage of the liquid phase and/or at least part of the gas phase inside the mixing channels.

Abstract: A combined liquid/vapor distributor and method of assembly are disclosed together with a method for collection and distribution of a liquid and a vapor in an exchange column. The combined liquid/vapor distributor is an apparatus for distributing a liquid and a vapor to or from a packing in an exchange column. The apparatus includes a distributor and a deck above and adjacent the distributor. The distributor has at least one vapor riser, which has generally parallel spaced apart upright walls and an open top and an open bottom opposite the open top. The distributor also has at least one liquid trough adjacent the vapor riser. The liquid trough has an open top and a floor having at least one aperture. The floor is opposite the open top of the liquid trough and is attached to at least one wall of the adjacent vapor riser.

Abstract: A liquid distributor for distributing liquid over the heat transfer surface of an evaporator includes a channel array including one or more supply channels and downwardly deviating distribution channels. Each distribution channel has a step-shaped expansion located downstream with respect to the supply channel and connecting therewith via a sharp point, restricting the liquid suction created in the distribution channel. Sharp points provided in the supply channel or channels further restrict the liquid suction.

Abstract: A liquid distributor in the form of a tray or trough network is provided with a plurality of rows of apertures through which liquid descends. A predistributor trough predistributes liquid onto the rows of apertures and is provided with bottom and side openings from which the liquid is distributed onto the plate. The side openings are located proximally with respect to the bottom openings to enhance uniformity of velocity profile of the liquid.