Abstract: A locking cam for securing suspension components in a vehicle. The locking cam has at least one surface that is textured to create a surface for engagement against and with a frame member upon tightening of the suspension components. The textured surface can have ridges or projects for engagement with the frame member.

Abstract: A frit comprising a plurality of grooves; a drain hole; a transverse crossing lane; wherein said plurality of grooves are substantially parallel to one another and extend longitudinally across said frit; wherein said plurality of grooves comprise at least two different lengths; wherein said transverse crossing lane is substantially perpendicular to said plurality of grooves; wherein said drain hole is located within said transverse crossing lane; wherein said drain hole is located at a center of said transverse crossing lane.

Abstract: A support beam is provided for supporting an internal such as a structured or grid packing within a mass transfer column. The support beam has an elongated web and upper and lower open flanges respectively positioned at upper and lower edge portions of the web. Each of the upper and lower open flanges has reinforcement rails that extend along a longitudinal length of the web and are spaced from opposed first and second faces of the web by spacers to create open fluid flow channels between the reinforcement rails and the first and second faces of the web. The upper and lower open flanges strengthen the web against deflection while minimizing horizontal surfaces that may lead to accumulation and growth of solids that may interfere with fluid flow to and from the internal.

Abstract: Distillation trays having improved efficiency and capacity are described. The improvement is accomplished with unique downcomer spout arrangements and bubble promoters which provide equal liquid distribution to all areas of the tray. The ratio of the open area of a contacting zone including part of a bubble promoter and associated deck zone over the open area of the downcomer spout zone on the adjacent tray for distributing liquid to the zone is essentially the same across the tray.

Abstract: A removable fixing device 1 for fixing equipment A on a support B, with: a compressible planar piece 5, an operating lever comprising a cam lever 2, and an assembly rod 3 having a first end and a second end; with: the second end of the assembly rod 3 being provided with a tightening means (4); the compressible planar piece 5, said operating lever comprising a cam lever 2 and the tightening means 4 arranged in tightened position being disposed around the assembly rod 3 in an assemblage; said operating lever comprising a cam lever 2 being arranged so that a rotation of the cam lever 2 about an axis y at right angles to the axis z of the assembly rod 3 induces a displacement of the cam lever 2 between a tightened position and a loosened position.

Abstract: A vehicle includes a vehicle wheel, a vehicle frame and an adjustment mechanism configured to move the vehicle wheel relative to the vehicle frame. The adjustment mechanism includes a cam stud and a cam spacer. The cam stud extends at least partially through the vehicle frame. The cam spacer is rotationally fixed to the cam stud. Rotating the cam spacer moves the vehicle wheel relative to the vehicle frame.

Abstract: Intraocular implants and methods of making intraocular implants are provided. The intraocular implant can include a mask adapted to increase depth of focus. The method of manufacturing the implant can include positioning the mask with an aperture on a protruding pin of a positioning mold portion. The protruding pin can be configured to center the mask in the intraocular lens.

Abstract: A distillation column is provided with a downcomer having an enlarged upper region to increase a processing rate for the removal of permanganate reducing compounds (PRCs) formed by the carbonylation of methanol in the presence of a catalyst to produce acetic acid. The distillation column includes a vertically extending distillation housing; and a plurality of tray assemblies, at least one of which includes a horizontally extending tray panel and a downcomer having, in a downward direction, an enlarged, funnel-shaped upper region defined by a top downcomer panel oriented at an angle to the vertical, and a lower region of substantially constant cross-sectional area defined by a vertically-oriented bottom downcomer panel.

Abstract: Provided are an apparatus for removing residual monomers and a method of producing a polyvinyl alcohol resin that can prevent drift of the organic solvent gas and residual of the polymerization solution on the trays and permits efficient removal of the unreacted monomers from the polymerization solution. An apparatus 1 for removing residual monomers having a column main body and valve trays 2 having multiple gas blowout ports each having openings only in a direction perpendicular to the flow direction of the polymerization solution 4 or openings directed downward in the flow direction of the polymerization solution, which are installed in multiple stages in the column main body is used in a monomer-removing step of removing monomers in a polymerization solution 4 by bringing an organic solvent gas, such as methanol gas, into contact with a polymerization solution 4 obtained from a polymerization reactor 3.

Abstract: Provided is a method and an apparatus for producing a polyvinyl alcohol that can reduce energy consumption without deterioration in quality of the product polyvinyl alcohol. First, one or more vinyl esters are polymerized or a vinyl ester and other copolymerizable monomers are copolymerized to give a polyvinyl ester. Then, a raw saponification solution containing the polyvinyl ester and an organic solvent is fed through a channel 1 and a saponification catalyst-containing solution is introduced into the center of the channel. They are then mixed with static mixers 2 and the mixture 4 is subjected to saponification reaction, as it is placed on a belt 3.

Abstract: A humidifier is provided that includes a main body having a discharge part, a base on which the main body is seated, the base having a suction part through which air is suctioned, a tray seated on the base to store water, and a disk assembly seated on the tray to humidify the air suctioned through the suction part.

Abstract: A reactor for carrying out a three-phase reaction of a liquid phase, a gaseous phase, and a catalyst over a fixed catalyst bed is disclosed. The liquid and gaseous phases are passed through the reactor via a mixing and distribution device positioned over the fixed catalyst bed. The mixing and distribution device includes a trough distributor for the liquid phase, having trough-shaped channels, outlet tubes in the trough-shaped channels for the liquid phase, a distributor plate below the trough distributor, and vertical nozzles, having one or more openings for the gaseous phase and one or more openings, arranged below the openings for the gaseous phase. For entry of the liquid phase, the nozzles are installed so that, at a predetermined liquid feed rate, the surface of the liquid on the distributor plate is below the openings for the gaseous phase and above the openings for the liquid phase.

Abstract: The present invention relates to a feed distribution device in separation columns and a method of operation. In particular it relates to distillation columns in which the feed stream is substantially liquid phase, or a mixture of gas and liquid upstream of the column, but where the feed vaporizes or vaporizes more when it enters the column. More specifically, the feed distribution device contains a plurality of opening which allow the feed to vaporize inside the column and where the openings are maintained in critical condition during operation. Significant advantage is achieved through the implementation and use of the present feed distribution device.

Abstract: A column structure (1) for the containment of high surface area packing (5) and absorbent liquid reagent for the removal of a target gas from a gas stream having an elongate upright wall structure defining a perimeter comprising a closed simple polygon or closed simple curve; a support structure extending inwardly from the perimeter of the column towards the top thereof; and slung tensile members (16) attached to the wall structure of the top support structure and extending downwardly to support at least internal column structure within the walls of the column.

Abstract: A separator comprising a vessel, a tray assembly positioned within the vessel, and a wall structure arranged to accumulate a first liquid and a second liquid. A first automatic drain valve is operable to automatically allow liquid accumulated above a first liquid outlet to pass from the vessel in such a way as to maintain a volume of the first liquid above the first automatic drain valve to create a liquid seal over the first automatic drain valve, and a second automatic drain valve is operable to automatically allow liquid accumulated above the level of an open upper end of the wall structure to pass from the vessel in such a way as to maintain a volume of the second liquid above the second automatic drain valve to create a liquid seal over the second automatic drain valve.

Abstract: Cross flow trays in a mass transfer column are provided with downcomers having one or more walls that extend from a tray deck of one the cross flow trays to an elevation below a tray deck of an underlying one of the cross flow trays. The downcomer walls are connected to and provide structural support for the tray decks of the cross flow trays.

Abstract: A feed distribution device in separation columns and a method of operation for such a device. In particular, distillation columns in which the feed stream is substantially liquid phase, or a mixture of gas and liquid upstream of the column, but where the feed vaporizes or partially vaporizes prior to or as it enters the column. More specifically, the feed distribution device contains a plurality of opening which allow the feed to vaporize prior to or as it enters the column and where the openings are maintained in critical condition during operation. Significant advantage is achieved through the implementation and use of the present feed distribution devices.

Abstract: A fluid distribution device is presented for the collection and distribution of fluid between reactor beds. According to various aspects, the device includes a collection tray, a mixing chamber in fluid communication with the collection tray, a rough distribution tray in fluid communication with the mixing chamber, and a fine distribution tray in fluid communication with the rough distribution tray. The rough distribution tray includes a vapor chimney.

Abstract: A contact and separation column (1) encasing a stack of one or more contact and separation cells (3). Each cell comprises: —a tray (4) with gas flow openings (6) opening into contact and separation units (7); —a downcomer (16) defining a liquid discharge; and —a liquid supply (17). Each contact and separation unit (7) comprises an upstream contact zone (8, 9) with liquid inlets (12), and one or more downstream separation zones (10) provided with a swirler (13) and a top end with a gas outlet (14). The cross-sectional area of the contact zone (8, 9) is larger than the cross-sectional area of the cross-sectional areas of the one or more separation zones of the contact and separation unit in question (10). Process for treating a gas with such a column.

Abstract: Provided is a dividing wall distillation column. The dividing wall distillation column includes a main column having a dividing wall. The main column includes a pressure equalization unit for pressure equalization between a preliminary divisional section and a main divisional section which are divided by the dividing wall. The dividing wall distillation column has an effect of enabling easier operations due to the uniform pressure drop between the two divisional sections divided by the dividing wall.

Abstract: An offshore co-current vapor-liquid contacting apparatus includes stages having contacting modules. Each contacting module includes a downcomer extending in a direction and has downcomer baffles distanced from each other in the direction to define downcomer cells within the downcomer. Each downcomer includes an outlet proximate to a co-current flow channel. A receiving pan extends substantially parallel to the downcomer and has receiving pan baffles distanced from each other in the direction to define receiving pan sections within the receiving pan. A vapor-liquid separation device has an inlet surface proximate to the co-current flow channel and an outlet surface above the receiving pan. Ducts are provided, with each duct having an upper end in fluid communication with a respective receiving pan section and a lower end in fluid communication with a selected downcomer cell in an immediately inferior stage.

Abstract: The gas-liquid contact column comprises at least an upper tray 10 and a lower tray 10, as well as a downcomer 2 for sending the liquid from the upper tray to the lower tray. The trays comprise gas ports. A packing 11 is arranged between the upper tray and the lower tray. The upper tray comprises means 12 for withdrawing liquid from the upper tray, the liquid withdrawn being distributed over the packing. The gas-liquid contact column is particularly well suited for absorption of the CO2 and of the H2S contained in a natural gas or in a syngas, and for capture of the CO2 contained in combustion fumes.

Abstract: An improved wet scrubber tray provides increased resistance to vibration-induced cracking. The self-supporting tray eliminates wastage of raw material, and additional internal stiffeners added to the tray make multiple intermediate stiffeners. The connection of the intermediate stiffeners to the perforated bottom plate is changed to eliminate the shop weld in the bottom plate. The holes in the perforated bottom plate are moved away from the boundaries of the tray to reduce their influence on boundary conditions. Trays are held down by plate material that is attached to the support grid, but not to the trays. Three field welds are applied to the sides of each tray to hold the trays in place relative to each other and are strategically placed to allow adjacent side stiffeners to act together as a composite section. Elastomeric material is used at the tray-to-grid attachments increases the damping of the system.

Abstract: Embodiments of apparatuses and methods for separating a paraffin isomerization-zone effluent are provided. In one example, an apparatus comprises a DIB column configured for fractionating the paraffin isomerization-zone effluent to form a branched C4 hydrocarbon-rich stream. The DIB column comprises a vessel. The vessel comprises a cylindrical wall that extends vertically and that encloses an internal cylindrical volume having a lower portion extending to an upper portion. An internal swage is disposed in the lower portion of the internal cylindrical volume. A plurality of fractionation trays includes an upper fractionation tray that is disposed in the internal cylindrical volume above the internal swage and a lower fractionation tray that is disposed in the internal swage. The lower fractionation tray has a smaller diameter than the upper fractionation tray.

Abstract: A separations tray assembly for use in a fluid-fluid exchange column. The separations tray assembly is of the type where a first fluid, in a continuous phase, is directed across successive trays in a serpentine flow path. A second fluid, in a dispersed phase ascends through apertures in the tray thus inducing interaction and mass transfer with the first fluid. In accordance with one aspect of the present invention, the separations tray further includes a diffuser skirt, having apertures disposed therein, operatively coupled to a fluid channel. The diffuser skirt is operable to direct the first fluid to cover substantially an entire volumetric cross-flow window between successive separations trays and to induce stirring and mixing of the first fluid and the second fluid to effect efficient mass transfer.

Abstract: A construction element for a plant for capture of an acidic gas using an aqueous amine absorbent, wherein at least a part of a surface of said element comprises a polyolefin, and a hydrolytically stable antioxidant, is described. Additionally, a liner comprising said polyolefin and the hydrolytically stable antioxidant, is described. The construction element may be a column, a pipe, an insert, like a column packing element or a tray. An apparatus for capturing CO2 using the construction elements, is also described.

Abstract: One exemplary embodiment may be a distribution tray for a vessel. Generally, the distribution tray includes a member, a compartment, and an insert. The member can form a first side and a second side. Typically, the first side is adapted to receive a liquid thereon. Additionally, the member can form a plurality of openings. Usually, the compartment extends through the member with a first portion protruding from the first side and a second portion protruding from the second side, and is adapted to permit the passage of a fluid there-through. The insert may be positioned within the compartment to constrict and then expand the passage of the fluid there-through.

Abstract: A separations tray assembly for use in a fluid-fluid exchange column. The separations tray assembly is of the type where a first fluid, in a continuous phase, is directed across successive trays in a serpentine flow path. A second fluid, in a dispersed phase ascends through apertures in the tray thus inducing interaction and mass transfer with the first fluid. In accordance with one aspect of the present invention, the separations tray further includes a diffuser skirt, having apertures disposed therein, operatively coupled to a fluid channel. The diffuser skirt is operable to direct the first fluid to cover substantially an entire volumetric cross-flow window between successive separations trays and to induce stirring and mixing of the first fluid and the second fluid to effect efficient mass transfer.

Abstract: One exemplary embodiment can be a process for contacting one or more fluids in a vessel. The process may include passing one or more fluids into a chamber from an overhead tray and providing a conduit outside the chamber coupling a respective spillway to a respective hole for increasing contact time inside the conduit. Typically, the chamber forms one or more sidewalls forming at least one hole and the overhead tray forms at least one spillway.

Abstract: Methods for continuously preparing cyclohexanone from phenol make use of a catalyst having at least one catalytically active metal selected from platinum and palladium. The process includes enriching phenol in a distillation fraction as compared to a subsequent fraction, wherein the subsequent fraction includes phenol and side-products having a higher boiling point than phenol. Distillation is carried out in a vacuum distillation column equipped with trays in the lower part of the column. In an upper part of the column, i.e., in the part above the feed inlet, packing material is present instead of trays in at least part thereof. The packing material has a comparable or improved separating efficiency, and provides a reduction of the pressure drop by at least 30%, preferably more than 50%, as compared to the case with trays in the upper part, under otherwise similar distillation conditions.

Abstract: Methods are disclosed for the selective absorption of gas components based on differences in their gas phase and liquid phase resistances to mass transfer. The methods advantageously utilize a gas-liquid contacting apparatus having contacting stages with co-current flow channels that can provide contacting with increased liquid phase resistance to mass transfer, for example in the spray regime such that the liquid is effectively dispersed as small droplets into the gas phase.

Abstract: The invention is a distributor tray for a column (1) for heat and/or material exchange between a gas (G) and a liquid (L), comprising at least one means providing passage of the gas through the tray (2). The means has at least one wall (4), defining on the surface of the tray (2) compartments (8) of substantially identical surface areas. Each compartment comprises at least one means (5) allowing passage of the liquid through the tray (2). The invention also has application to a gas/liquid contact column, a gas treatment unit, a CO2 capture unit, a distillation unit, an offshore floating barge comprising such a distributor tray and a method of manufacturing the tray.

Abstract: A tray valve assembly for a process column of a type wherein a first, heavier fluid flows downwardly from a downcomer onto a tray and thereacross in a first direction through which a second, lighter fluid flows upwardly therethrough for interaction and mass transfer with the heavier fluid before passing therefrom. A plurality of valves disposed across a surface of the tray and mounted above a plurality of apertures on the surface of the tray, each valve of the plurality of valves comprising a top surface and at least one securement leg. A first securement leg of is adapted to intercept the heavier fluid flow in the first direction forming a diverting baffle for engaging the heavier fluid flow across the tray. Each valve includes at least one aperture to facilitate the lighter fluid flow therefrom and further comprising a first aperture in the first securement leg.

Abstract: Cross flow trays are provided with a support system. The support system interconnects the upper cross flow tray to a downcomer of the lower cross flow tray to provide support for the upper tray. In some aspects, the support system may also interconnect the downcomer of the lower cross flow tray to an upper tray of an underlying pair, providing additional support for the assembly. Such tray assemblies may facilitate easier installation without impeding the performance of the column.

Abstract: A volatile organic compound removal device includes a cabinet having first and second slidable drawers movable between inserted and extended positions. A downcomer tube is downwardly and slidably received in an aperture of the first drawer. A sealing flange extends horizontally outward from a downcomer tube perimeter and extends beyond the aperture when the downcomer tube is received in the aperture. The sealing flange faces an upward facing surface of the first drawer and supports the downcomer tube to the first drawer using only a weight of the downcomer tube applied through the sealing flange to the upward facing surface. A removable seal pot pan is supported on an upward facing surface of the second drawer, which is aligned directly below and receives a lower end of the downcomer tube.

Abstract: Apparatuses and methods are disclosed for distributing vapor and liquid flow. Problems with maldistribution, due to out of level positioning of the distributor tray, are addressed by varying the height of the caps and/or their openings to control the liquid flow profile (distribution) that results due to the rising liquid level.

Abstract: A valve-tray assembly and method for lighter fluid heavier fluid contact towers. The active area of the tray is constructed with valves having multiple lighter fluid discharge areas facilitating improved mass transfer efficiency. The valves include first and second support legs oriented in line with the heavier fluid flow with both legs and the valve top constructed with apertures wherein the heavier fluid may flow into engagement with the lighter fluid passing from beneath the tray up, through and out of the valve.

Abstract: A contact tray is provided with a tray deck and dividing walls which form groupings of one or more cans and one or more downcomer inlets distributed across the tray deck. The cans have walls that surround vapor openings in the tray deck that permit upward passage of a vapor stream into the cans. Downcomers extend downwardly from the downcomer inlet and are positioned for delivering a liquid stream into the center of cans positioned on a tray deck of an underlying contact tray. Discharge openings are provided in the walls of the cans to allow the liquid stream to exit the cans. The dividing walls direct the exiting liquid stream into the downcomer inlets in the same grouping and prevent or impede the liquid stream from flowing to a low side of the tray deck.

Abstract: An elongated support beam is provided for supporting internals such as liquid collectors, liquid distributors, packing supports, or trays within a mass transfer column. The support beam is divided longitudinally into a lower beam segment and an upper beam segment that are joined together by a plurality of connectors at one or more longitudinally spaced-apart positions. The connectors serve to stiffen and resist lateral deflection of the lower and upper beam segments in relation to each other and to transfer the load carried by the upper beam segment to the lower beam segment or vice-versa. By dividing the support beam into lower and upper beam segments, each of the lower and upper beam segments can be passed through a manway opening in a shell of the mass transfer column prior to assembly of the support beam or following disassembly of the support beam within the mass transfer column.

Abstract: A divided exchange column includes a shell column having a first longitudinal axis, a cylindrical wall spaced apart from and surrounding the first longitudinal axis and defining a first interior space, a first divided wall column having a second longitudinal axis substantially parallel to the first longitudinal axis, and a second divided wall column having a third longitudinal axis substantially parallel to the first and the second longitudinal axes, where the first divided wall column and the second divided wall column are positioned in the first interior space of the shell column.

Abstract: A fractionation tray for use in a process column. The fractionation tray is of a type where a first fluid flows downwardly from a downcomer onto the fractionation tray and across the fractionation tray in a first direction. A second fluid flows upwardly through the fractionation tray for interaction with the first fluid. The fractionation tray includes an upper tray section, a lower tray section that is operable to removably engage the upper tray section, a joint region which includes an area of overlap between the upper tray section and the lower tray section. The joint region allows passage of the second fluid therethrough.

Abstract: A distillation column is provided with a downcomer having an enlarged upper region to increase a processing rate for the removal of permanganate reducing compounds (PRCs) formed by the carbonylation of methanol in the presence of a catalyst to produce acetic acid. The distillation column includes a vertically extending distillation housing; and a plurality of tray assemblies, at least one of which includes a horizontally extending tray panel and a downcomer having, in a downward direction, an enlarged, funnel-shaped upper region defined by a top downcomer panel oriented at an angle to the vertical, and a lower region of substantially constant cross-sectional area defined by a vertically-oriented bottom downcomer panel.

Abstract: A tray valve assembly for a process column of a type wherein a first, heavier fluid interacts with a second, lighter fluid. A plurality of valves are disposed on a surface of the tray. Each valve of the plurality of valves includes a top surface and at least one securement leg. A first securement leg of is adapted to intercept the first, heavier fluid flow thereby forming a diverting baffle. Each valve includes at least one aperture to facilitate the second, lighter fluid flow therefrom. The at least one aperture is adapted to allow the second, lighter fluid to interact with the first, heavier fluid. Each valve includes a plurality of open side regions. Each valve is adapted to allow the second, lighter fluid to pass outwardly therefrom generally in a direction of the first heavier fluid.

Abstract: An improved wet scrubber tray provides increased resistance to vibration-induced cracking. The tray is self supporting to eliminate wastage of raw material, and additional internal stiffeners added to the tray make multiple intermediate stiffeners. The connection of the intermediate stiffeners to the perforated bottom plate is changed to eliminate the shop weld in the bottom plate. The holes in the perforated bottom plate are repositioned so that they are moved away from the boundaries of the tray to reduce their influence on boundary conditions. The thickness of the tray material may be increased to lower the vibratory stresses. The mechanism for holding the trays themselves within the spray absorber tower is changed so that the trays are now held down by plate material that is attached to the support grid, but not to the trays.

Abstract: An apparatus for collecting/redistributing a flow of liquid descending in an exchange column containing a layer of packing that includes: a plurality of horizontally spaced longitudinal members, each member having an inner side and an upper end adjacent a bottom of the layer of packing; at least one plate vertically spaced from the bottom of the layer of packing, each plate adapted to collect a portion of the flow of the descending liquid and having opposing ends connected to the inner sides of a pair of the longitudinal members; and at least one vapor riser in fluid communication with the plate and adapted to receive and transmit at least a portion of a stream of a vapor ascending in the exchange column from below to above the plate, each vapor riser having a cap vertically spaced apart from the bottom of the layer of packing.

Abstract: The valve cover has a guide vane extending laterally and downwardly from the central portion towards and in spaced relation to the tray deck for deflecting a majority of the vapor passing upwardly through an orifice downward towards the tray deck. A de-entrainment device with a downwardly angled deflector in vertical alignment with an orifice in the tray deck may be integrated or not with the valve cover below the tray deck.

Abstract: Embodiments of vessels including liquid drain pipes are provided, as are embodiments of methods for draining liquid from reactor internals. In one embodiment, the vessel includes a vessel shell, a tray mounted within the vessel shell and over which liquid accumulates up to a maximum liquid level during vessel operation, and a liquid drain pipe. The liquid drain pipe includes a tubular body attached to the tray and projecting upward therefrom, a vapor inlet formed in the tubular body above the maximum liquid level, a liquid inlet formed in the tubular body between the maximum liquid level and the tray, and a drainage port formed in the tubular body and positioned to direct accumulated liquid above the tray to an area below the tray to permit the drainage of accumulated liquid from over the tray during vessel shutdown.

Abstract: Cross flow trays in a mass transfer column are provided with downcomers having one or more walls that extend from a tray deck of one the cross flow trays to an elevation below a tray deck of an underlying one of the cross flow trays. The downcomer walls are connected to and provide structural support for the tray decks of the cross flow trays.

Abstract: A gas-liquid contact column tray has a section including a gas pathway (SAA) and a liquid pathway section (SD) delimited by at least one downspout, wherein a deflecting system including a roof is included, located above the liquid gas interface at the level of the liquid pathway section (SD), in order to apportion the gas phase over a surface section greater than the section including the means of gas pathway (SAA). In a method for gas-liquid contact in such a column, most of the gas phase part is redirected and apportioned over the whole pathway section available for gas, corresponding to the tray section provided with the gas pathway (SAA), increased by the liquid pathway section (SD), using a deflecting system consisting of the roof located higher than the gas-liquid interface level of the liquid pathway section (SD), and the liquid collected is evacuated toward the lower tray.

Abstract: A downcomer for a gas-liquid contacting device. The downcomer may include first and second spaced apart side walls, first and second end walls, a floor, and first and second opposing discharge walls. Generally, each end wall is coupled to a respective end of the first and second side walls. Typically, the floor is coupled to the side walls and end walls, and the floor has at least one section adapted for permitting the passage of liquid there-through. The first and second opposing discharge walls can be coupled to respective first and second side walls and having respective ends below the floor.