Jet Plates Patents (Class 261/114.3)
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Patent number: 11958001Abstract: The present disclosure relates to a valve tray for use in a chemical process column. The valve tray includes a plurality of apertures formed therein. A plurality of valves are maintained in a spaced relationship relative to individual apertures of the plurality of apertures. An area of the individual apertures is less than an area of individual valves of the plurality of valves.Type: GrantFiled: January 26, 2018Date of Patent: April 16, 2024Assignee: SULZER MANAGEMENT AGInventors: Phillip Bradley Fleming, Larry W. Burton, Michael J. Binkley
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Patent number: 10821409Abstract: A cylindrical or annular polymeric bioreactor is disclosed which provides enhanced mixing and aeration of the growth medium while simultaneously offering reduced mechanical shear force.Type: GrantFiled: November 30, 2017Date of Patent: November 3, 2020Assignee: Finesse Solutions, LLCInventors: Mark D. Selker, Barbara Paldus
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Patent number: 9027911Abstract: The present invention relates to a valve tray for mass transfer columns having a base plate, at least one liquid intake and at least one liquid outlet for forming a liquid flow having a direction of flow on the base plate, a plurality of gas entry orifices formed in the base plate and also a plurality of fixed valves covering the gas entry orifices, which fixed valves are formed in one piece with the base plate and in each case include a valve roof at a distance to the base plate and also a valve rear side and a valve front side, wherein between the base plate, the valve rear side, the valve front side and the valve roof of each fixed valve, at least one side gas outlet orifice is formed in each case. The side gas outlet orifices of the fixed valves can taper in the direction of flow of the liquid flow.Type: GrantFiled: May 3, 2011Date of Patent: May 12, 2015Assignee: RVT Process Equipment GmbHInventors: Markus Lehner, Andreas Wolgast, Andreas Gertloff
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Patent number: 9011790Abstract: 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.Type: GrantFiled: June 20, 2008Date of Patent: April 21, 2015Assignee: BASF SEInventors: Stefan Iselborn, Andreas Daiss, Reiner Geier, Marcus Bechtel, Michael Wille, Benjamin Hepfer, John Sauter
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Patent number: 8673246Abstract: 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.Type: GrantFiled: March 23, 2011Date of Patent: March 18, 2014Assignee: UOP LLCInventors: Pengfei Chen, Zhanping Xu
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Patent number: 8413967Abstract: 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.Type: GrantFiled: June 13, 2009Date of Patent: April 9, 2013Assignee: Babcock & Wilcox Power Generation Group, Inc.Inventors: Ronald B. Johnson, Ronald Dureiko, David Peterson, J. Jeffrey Kidwell
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Patent number: 7931871Abstract: The invention concerns an inner tray, arranged inside a chamber, comprising a plurality of parallel beams (1), located in a common horizontal plane and fixed through their ends to the wall of the chamber, and, between said beams and supported thereby, rows of adjacent rectangular plates (2), completely covering the space between the beams. The invention is characterized in that the supporting edges (3) of the plates (2) through which the latter are supported on the beams (1), are folded downwards by two substantially right-angled folds, and in that each of the edges (4) of the plates (2), perpendicular to the beams (1) is folded so as to form a female part (4a) or a male part (4b) capable of being respectively nested in a male (4b) or female (4a) part formed by the folded edge of the adjacent plate. The invention also concerns a chamber containing such a tray.Type: GrantFiled: December 7, 2005Date of Patent: April 26, 2011Assignee: Total Raffinage MarketingInventors: Pedro Nascimento, Pedro Da Silva, Matthew Allen
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Patent number: 7731822Abstract: A column for distillation or fluid-fluid separation is oriented at an angle to the horizontal other than vertical to provide increased transfer plate surface area within the interior of a column of determined diameter and to reduce overall height of the structure.Type: GrantFiled: February 18, 2005Date of Patent: June 8, 2010Inventor: Strom W. Smith
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Patent number: 7718138Abstract: The present invention relates to a device and a process for introducing gas into a fluidised bed reactor having at least one gas inlet pipe (2, 3) located underneath and/or above the fluidised bed for introducing gas into the fluidised bed, characterized in that the gas inlet pipe (2, 3) has gas-swirling means upstream of and/or at its mouth.Type: GrantFiled: May 26, 2003Date of Patent: May 18, 2010Assignee: Vinnolit Technologie GmbH & Co. KGInventors: Klaus Krejci, Peter Kammerhofer, Ingolf Mielke, Uwe Wäterling
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Patent number: 7708258Abstract: The tray has an infusion field of infusion tab valves adjacent the inlet to dissipate the momentum of the liquid flowing across said infusion field. Each valve includes a vertically upstanding wall of a height to obstruct the flow of liquid and the valves are disposed in a staggered array. An adjacent bubbling area has openings for the passage of an ascending flow of vapor into contact with the liquid/vapor mixture flowing across the area. Each infusion tab valve may also have a push valve incorporated therein.Type: GrantFiled: December 21, 2006Date of Patent: May 4, 2010Assignee: Sulzer Chemtech AGInventors: Mark W. Pilling, Markus Fischer, Dale Edward Nutter
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Patent number: 7695593Abstract: The helical fractionating column according to the invention falls into the field of oil separation apparatus for the petroleum refining industry, which includes a column body (8), and is characterized in that the inside of the column body (8) is divided into three sections, the lower section being jet tray section, the middle section being packing section, and the upper section being floating valve section. The helical fractionating column has many advantages, such as having enhanced integrity of separation, decoloration and deodorization, simple structure, convenient manufacturing and maintenance, and low investment cost as well as high product quality etc. Thus, the present invention is worthy to be extended in the petroleum refining industry which uses waste plastics and rubbers as raw materials.Type: GrantFiled: January 28, 2006Date of Patent: April 13, 2010Inventor: Fusheng Xie
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Patent number: 7624972Abstract: A mass or heat transfer device is provided in the form of a tray with at least one movable or fixed valve covering an opening to prevent liquid flowing in the design flow direction to pass through the opening.Type: GrantFiled: November 7, 2007Date of Patent: December 1, 2009Inventor: Carlos Jose Trompiz
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Patent number: 7597801Abstract: A wastewater treatment plant includes a reaction tank connected to an wastewater supply tube and an aeration apparatus to receive wastewater therein, a sludge separation unit dividing an internal space of the reaction tank into upper and lower sections to increase an amount of dissolved oxygen by increasing an contact area of the wastewater and bubbles and to separate relatively light materials by moving low density matters existed on a surface of each section upward in turn, an air exhaust tube mounted on the reaction tank to exhaust bubbles passing through the sludge separation unit out of the reaction tank, a treated water exhaust tube mounted on the reaction tank to exhaust the wastewater that is treated by passing through the sludge separation unit, and a settling tank provided on a bottom of the reaction tank to concentrate and exhaust the settled sludge.Type: GrantFiled: June 15, 2004Date of Patent: October 6, 2009Assignee: EcoDays Co., Ltd.Inventor: Hong-Bok Choi
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Publication number: 20090115079Abstract: A mass or heat transfer device is provided in the form of a tray with at least one movable or fixed valve covering an opening to prevent liquid flowing in the design flow direction to pass through the opening.Type: ApplicationFiled: November 7, 2007Publication date: May 7, 2009Inventor: Carlos Jose Trompiz
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Patent number: 7513271Abstract: The fluid inlet device for a column includes an inflow stub and a deflection unit. The deflection unit includes an input zone with a plurality of inlet passages of constant cross-sections that merge into diffuser-like passages formed by curved guide lamellae. The curved guide lamellae diffuse the flow of fluid from the lateral passages laterally and circumferentially of the column to separate a high density phase, such as liquid drops, from a low density phase, such as a gas, under centrifugal force. The curved lamellae also direct the flow of fluid from the central passages downwardly of the column.Type: GrantFiled: May 9, 2007Date of Patent: April 7, 2009Assignee: Sulzer Chemtech AGInventors: Christian Gottlieb Bachmann, Pierre Schaeffer, Felix Muggli
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Publication number: 20080018003Abstract: The valve for a contract tray employs an aperture in a deck that is of rectangular or trapezoidal shape with upstanding walls at the sides of the aperture. The valve body is disposed in the aperture with a cover above the aperture and legs that extend downwardly to interfit with at least the upstream end of the walls to block the liquid flow. The valve body may be fixed or movable. In the movable embodiment, the valve body is seated on the walls about the aperture to close the aperture. The ascending vapor lifts the valve to allow bubbling of the vapor in the liquid on the deck.Type: ApplicationFiled: July 18, 2006Publication date: January 24, 2008Inventors: Mark W. Pilling, Dale Edward Nutter
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Patent number: 7306204Abstract: A column for the thermal treatment of mixtures which contain one or more polymerizable compounds is proposed, which column has dual-flow trays with openings whose diameter is constant within a dual-flow tray, the dual-flow trays having openings of decreasing diameter with increasing distance from the feed of the mixture to be treated.Type: GrantFiled: November 21, 2002Date of Patent: December 11, 2007Assignee: BASF AktiengesellschaftInventors: Joachim Thiel, Juergen Schroeder
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Patent number: 7029557Abstract: The invention relates to a method for producing a highly pure, aqueous hydroxylamine solution by distilling an aqueous solution, devoid of salt, of a hydroxyl ammonium salt in a plate column comprising at least two mechanical plates. Said method is characterised in that packing bodies are arranged between at least two plates of the plate column over the cross-section of said column.Type: GrantFiled: July 2, 2002Date of Patent: April 18, 2006Assignee: BASF AktiengesellschaftInventors: Karl-Heinz Wostbrock, Joachim Thiel, Heinz Krüger, Eckhard Ströfer, Markus Weber, Bernd Gerber, Bernd Rumpf, Bernd Sachweh, Steffen Kerth
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Patent number: 6966548Abstract: This invention is directed to a cyclonic vapor/liquid contacting device and distillation or related mass transfer or heat transfer processes employing its use, such as fluid catalytic cracking. Liquid feed is introduced near the floor of the cyclone via downcomer or plenum. Vapor enters through sieve holes in the bottom of the cyclonic device. Near the floor are angled tabs or vanes that impart a spin to the vapor rising up through the floor. The tabs or vanes mix the liquid and vapor. The liquid is then thrown toward the cyclone wall, where it exits through slots in the wall. A second set of tabs or vanes, located about in the middle of the cyclone, imparts additional spin to the vapor and entrained liquid rising through the cyclone. This improves liquid collection by the cyclone, especially in cases where a heavy liquid load dampens the spin action of the vapor in the base of the cyclone.Type: GrantFiled: July 1, 2003Date of Patent: November 22, 2005Assignee: ExxonMobil Research and Engineering CompanyInventors: John Scott Buchanan, Berne K. Stober
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Patent number: 6877725Abstract: This invention is directed to a cyclonic vapor/liquid contacting device and distillation or related mass transfer or heat transfer processes employing its use, such as fluid catalytic cracking. Liquid feed is introduced near the floor of the cyclone via downcomer or plenum. Vapor enters through sieve holes in the bottom of the cyclonic device. Near the floor are angled tabs or vanes that impart a spin to the vapor rising up through the floor. The tabs or vanes mix the liquid and vapor. The liquid is then thrown toward the cyclone wall, where it exits through slots in the wall. A second set of tabs or vanes, located about in the middle of the cyclone, imparts additional spin to the vapor and entrained liquid rising through the cyclone. This improves liquid collection by the cyclone, especially in cases where a heavy liquid load dampens the spin action of the vapor in the base of the cyclone.Type: GrantFiled: July 1, 2003Date of Patent: April 12, 2005Assignee: Mobil Oil CorporationInventors: John Scott Buchanan, Berne K. Stober
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Publication number: 20040183217Abstract: 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.Type: ApplicationFiled: February 13, 2004Publication date: September 23, 2004Applicant: QVF Engineering GmbHInventor: Gottfried Dichtl
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Patent number: 6592106Abstract: A vapor-liquid contact tray is provided with at least two tray panels that are releaseably together along their overlapped margins by a locking hinged joint. The joint is formed by fingers in one tray panel that extend through slots located in the other tray panel. Offset bends are formed in the tray panels so that the overlapped margins do not extend above the top surface of the tray. The hinged joint includes a locking mechanism that prevents lateral separation of the tray panels once they have been releaseably joined together. The locking mechanism is formed by a downturned locking flange positioned between the fingers in one of the tray panels and extending downwardly into and, preferably through, openings located in the overlapped margin of the other tray panel.Type: GrantFiled: January 8, 2002Date of Patent: July 15, 2003Assignee: Koch-Glitsch, LPInventor: Raymond H. Eaton, Jr.
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Patent number: 6588735Abstract: This invention relates to a gas-liquid contact tray having a bubble area and a downcomer having a downcomer opening, in which a self-draining vent tube is present in the downcomer and fluidly connects the upper portion of the downcomer with a space above the tray.Type: GrantFiled: January 10, 2001Date of Patent: July 8, 2003Assignee: Shell Oil CompanyInventors: Bernardinus Henricus Bosmans, Wilhelmus Adrianus Theodorus Uijen
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Patent number: 6588736Abstract: A gas/liquid contacting tray assembly is provided, including a perforated sheet and elongated cover strips arching over the perforations in the sheet. The cover strips have slots with liquid conveying strips in them for conveying liquid along the slots while mixing gas therewith. This reduces stagnant areas downstream of the cover strips, and sedimentation of solids in these areas, thus increasing the gas/liquid mixing and handling capacity while reducing the frequency of shut downs. A further slot, extending in the opposite direction to the one above, may be provided in the cover strip and have a conveying strip for conveying liquid mixed with gas to the other end of the cover strip and further reducing the formation of stagnant areas. The cover strips may taper inwardly width-wise in a downstream direction.Type: GrantFiled: December 14, 2000Date of Patent: July 8, 2003Inventors: Karl T. Chuang, Adam T. Lee
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Publication number: 20020190403Abstract: A stepped downcomer apparatus for use in a vapor-liquid contact apparatus having an intermediate level step platform with a preferred tri-edge peripheral edge and corresponding step panels extending down from that edge to form a sealing step panel wall. As a preferred support device, extensions extend in chordal fashion out from the interior vertical edge of the opposite side step wall panels and either directly or indirectly by way of support bars into a supporting relationship with a tower of the vapor-liquid contact apparatus. A main panel extends up from the interior edge of the platform and up to the above positioned tray. A weir may extend above the above positioned tray that is an extension of the main panel. This main panel is attached to the support bars and supports the step platform and walls and extensions either alone or with added support members. A tray support ledge extends inwardly from the downcomer to provide support to the upper tray.Type: ApplicationFiled: June 13, 2001Publication date: December 19, 2002Inventors: Dale E. Nutter, Mark W. Pilling, Christina J. Campbell
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Patent number: 6386520Abstract: A fluid inlet device for introducing a mixture of liquid and gas into a column provided with an inlet nozzle and with a horizontal gas/liquid contact tray arranged in the column below the inlet nozzle provided with a number of elongated downcomers between which bubbling areas are located, which inlet device consists of an inlet end that is in fluid communication with the inlet nozzle and a number of vertical vanes placed one behind the other, wherein each vane consists of two interconnected parts, an intercepting part and an outwardly directed deflecting part, wherein the intercepting part extends to the inlet end of the inlet device, and wherein an outlet channel defined by the deflecting parts of two adjacent vanes opens above a bubbling area of the contact tray.Type: GrantFiled: January 10, 2001Date of Patent: May 14, 2002Assignee: Shell Oil CompanyInventor: Malcolm William McEwan
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Patent number: 6375921Abstract: A bubble column can be operated using countercurrent flow including perforated trays. The space-time yield of gas-liquid reactions can be considerably increased if the perforated trays have a substantially uniform distribution of holes, if the cross-sectional area of the individual holes is 0.003 to 3 mm2, particularly 0.01 to 0.5 mm2, and if the open area of the trays is 3 to 20%, particularly 3 to 10%, and if the bubble column comprises passages for liquid between adjacent liquid zones. The bubble column can be used for carrying out gas-liquid reactions, such as oxidation reactions with air, with the gas and liquid preferably being passed in countercurrent flow through the column. Cocurrent flow may also be used.Type: GrantFiled: May 23, 2000Date of Patent: April 23, 2002Assignee: Degussa Huls A.G.Inventors: Hubertus Eickhoff, Rüdiger Schütte
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Patent number: 6345811Abstract: 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.Type: GrantFiled: December 27, 1999Date of Patent: February 12, 2002Assignees: China Petro-Chemical Corporation, Zhejiang University of TechnologyInventors: Xiaomei Yu, Jun Tian, Jiazhong Zhu, Ou Li, Zuming Zheng, Kejian Yao
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Patent number: 6325361Abstract: In order to bring a gas and a liquid into contact with one another, for example so as to exchange, remove or add components or calorific value present in the gas and/or liquid, the liquid is guided along one or more walls which are provided with small openings, and the gas is guided into the liquid, via these openings, by allowing this liquid to flow along the walls or by moving the walls along the liquid. In order to increase the contact time between gas and liquid, the gas is guided into the liquid in a direction which essentially corresponds to the direction of movement of the liquid with respect to the wall which is provided with openings. A venturi effect is generated in the region of the openings, since subatmospheric pressure is produced at the location where the openings open into the stream of liquid.Type: GrantFiled: July 19, 1999Date of Patent: December 4, 2001Inventor: Albert Van Duijn
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Publication number: 20010030373Abstract: This invention relates to a gas-liquid contact tray consisting of a bubble area and a downcomer having a downcomer opening, in which a self-draining vent tube is present in the downcomer and fluidly connects the upper portion of the downcomer with a space above the tray.Type: ApplicationFiled: January 10, 2001Publication date: October 18, 2001Inventors: Bernardinus Henricus Bosmans, Wilhelmus Adrianus Theodorus Uijen
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Publication number: 20010030374Abstract: The invention relates to a gas-liquid contacting tray provided with a bubble area, a liquid discharge area and an overflow weir along the boundary of the bubble area and the liquid discharge area, on which tray, when in use, a liquid flow in the direction of the liquid discharge area is present just above the surface of the bubbling area, in which the overflow weir is formed such that it guides the liquid flow in a backwards direction.Type: ApplicationFiled: January 10, 2001Publication date: October 18, 2001Inventors: Bernardinus Henricus Bosmans, Wilhelmus Adrianus Theodorus Uijen
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Patent number: 6299146Abstract: The vapor-liquid contacting tower contains multiple trays having multiple openings and multiple rectangular downcomers with multiple bottom openings. At least a pair of directing slots and at least a pair of directing baffles are installed in the liquid receiving zone of the tray and under the bottom openings of a downcomer of the adjacent overlying tray.Type: GrantFiled: December 22, 1999Date of Patent: October 9, 2001Assignees: China Petro-Chemical Corp., Zhenjiang University of Tech.Inventors: Xiaomei Yu, Chongsi Xu, Jingzhong Zhu, Ou Li, Zuming Zheng, Kejian Yao, Jun Tian
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Patent number: 6267805Abstract: The invention relates to an apparatus for scrubbing with water a continuous flow of charged gas, the apparatus including a scrubbing chamber; an inlet via which the scrubbing water is fed into the scrubbing chamber; a scrubbing throat for mixing the scrubbing water with the charged gas in the scrubbing chamber; a removal device for removing the scrubbing water and the collected particles; and a removal device for removing the continuous flow of at least partially scrubbed gas.Type: GrantFiled: October 15, 1997Date of Patent: July 31, 2001Assignee: Societe Anonyme dite Air Industrie Systemes - A.I.S.Inventors: André Cordier, Didier Sedaries, Christophe Pierin, Alain Eyraud
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Patent number: 6250611Abstract: Vapor-liquid contact apparatus for chemical processing includes a vessel containing a plurality of spaced horizontal trays which support a vapor-liquid mixture, and downcomers which carry liquid down from one tray to another. Each tray has an infeed area, a bubbling area which has apertures for introducing vapor into the vapor-liquid mixture on the tray, and a liquid exit opening at the downstream end of the bubbling area. The downcomer receives the vapor-liquid mixture from the bubbling area, and it has a floor which increases the residence time of the vapor-liquid mixture in the downcomer. The floor forms an outlet which feeds liquid to the infeed area of a subsequent tray. The downcomer outlet is an elongated slot formed between a convex outer edge of the floor and a convex outer edge of the downcomer cross-section.Type: GrantFiled: October 7, 1999Date of Patent: June 26, 2001Assignee: Sulzer Chemtech USA, Inc.Inventors: Mark W. Pilling, Dale E. Nutter
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Patent number: 6221133Abstract: The invention provides a cellular packing including a vapor/liquid separation device that can be stacked vertically with minimum wasted space. The packing uses static vanes in each cell to direct the liquid component of a vapor/liquid mixture to exit slots in a first cell and a recirculation path for the liquid to be contacted with vapor again in a second cell located below the first.Type: GrantFiled: December 29, 1999Date of Patent: April 24, 2001Assignee: Norton Chemical Process Products CorporationInventor: Frank D. Moore
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Patent number: 6193222Abstract: A gas-liquid contact tray having a substantially planar deck, a plurality of apertures extending through the deck, and a plurality of valve covers disposed over the apertures. The deck has an upper surface and a lower surface. Each of the valve covers has a cover plate and a first leg extending between the cover plate and the deck for supporting the cover plate over the upper surface of the deck. The cover plate has a perimeter edge having a plurality of alternating extensions and depressions. During operation of the tray a vapor ascends through the apertures and fluid is deposited onto the tray, the fluid flowing across at least a portion of the deck and contacting the ascending vapor, and the fluid thereafter exiting off of the tray.Type: GrantFiled: February 8, 1999Date of Patent: February 27, 2001Inventor: Zhongliang Fan
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Patent number: 6189872Abstract: The present invention provides an apparatus for use in the contact between a vapor and a liquid. In one embodiment, a column is provided having a generally vertical shell. A plurality of vertically spaced, horizontal fluid contacting trays for contacting the vapor and the liquid within the column may also be provided. Each horizontal contacting tray may include a liquid receiving area, an active perforated area and a liquid discharge area. An imperforate inlet area may be formed from a perimeter section of the liquid receiving area, and secured to the inner surface of the column. A downcomer may be positioned above said inlet area and inward from the inner wall surface of the column whereby the downcomer receives liquid from the liquid discharge area of an upper tray and directs flow to the inlet area. A froth activator may also be provided for contacting the liquid from the downcomer.Type: GrantFiled: October 23, 1998Date of Patent: February 20, 2001Assignee: AMT International, Inc.Inventor: Karl T. Chuang