Froth reduction devices for gas-liquid contractors

Abstract

Disclosed herein is a method for reducing or preventing froth formation in a gas-liquid contactor. The method includes contacting a region of gas-liquid contact within a flow system of a device. The device includes at least one super wettable surface adapted to reduce or prevent froth formation at the region of the gas-liquid contact.

Description

Docket No. 28482-1335FROTH REDUCTION DEVICES FOR GAS-LIQUID CONTACTORSCROSS-REFERENCE TO RELATED APPLICATION(S)

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 679,959, filed August 6, 2024, the disclosure of which is hereby incorporated by reference herein in its entirety.FIELD OF INVENTION

[0002] The present disclosure generally relates to the field of froth reduction or prevention. More specifically, it relates to a method of froth reduction or prevention in a gas-liquid contactor.BACKGROUND

[0003] Froth in chemical reactors can cause inconsistencies in reactor conditions and inhibit or stop the flow of inlet and outlet pipes in a reactor system. Currently, strategies for addressing excessive frothing in chemical reactors include the implementation of anti-froth additives that introduce additional complications such as impurities in chemical products as well as increased catalyst deactivation. Other strategies such as the design of larger reactors to accommodate the volume of froth or the use of mechanical defoamers introduce increased capital or operating costs.

[0004] Excessive frothing is a recurring problem in gas-liquid contactor units such as distillation columns, absorbers, strippers, quench towers, and stirred vessels. Current solutions for excessive frothing in gas-liquid contactors include the design of larger units to accommodate the froth, the use of mechanical defoamers (ultrasonic or rotary devices), or the addition of antifoams to the system. These solutions are associated with increased capital or operating costs, and in the case of anti-foam additives, there can be issues with product purity, catalyst deactivation, and fouling on the process equipment over time.SUMMARY

[0005] The following presents a simplified summary of various aspects of the present disclosure in order to provide a basic understanding of such aspects. This summary is not an extensive overview of the disclosure. It is intended to neither identify key or critical elements of the disclosure, nor delineate any scope of the particular embodiments of the disclosure or anyDocket No. 28482-1335 scope of the claims. Its sole purpose is to present some concepts of the disclosure in a simplified form as a prelude to the more detailed description that is presented later.

[0006] In one aspect of the present disclosure, a method for reducing or preventing froth formation in a gas-liquid contactor comprises: contacting a region of gas-liquid contact within a flow system with a device comprising at least one superwettable surface adapted to reduce or prevent froth formation at the region of the gas-liquid contact. The gas-liquid contactor may be adapted to include a flowing fluid, such as a salt-containing fluid, as well as slurries.

[0007] In at least one embodiment, the region of gas-liquid contact comprises a bubblecontaining liquid. In at least one embodiment, the bubble-containing liquid comprises a solvent. In at least one embodiment, the region of gas-liquid contact comprises a gas. In at least one embodiment, the gas-liquid contactor comprises at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, or reactor agitator. In at least one embodiment, the device forms the surface of at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, or reactor agitator. In at least one embodiment, the device is a free-standing flotation device adapted to float on a liquid surface of the region of gas-liquid contact. In at least one embodiment, the device comprises a mesh or grid installed in the region of gas-liquid contact. In at least one embodiment, the reduction or prevention of froth formation comprises merging the gas contained within the froth with the gas of the region of gas-liquid contact.

[0008] In at least one embodiment, the superwettable surface comprises a hydrophobic surface. In at least one embodiment, the superwettable surface comprises a hierarchical structure. In at least one embodiment, the hierarchical structure includes ridges, pores, spikes, and / or posts.

[0009] In at least one embodiment, the superwettable surface comprises a coating. In at least one embodiment, the coating comprises a binder. In at least one embodiment, the coating comprises a layer of hydrophobized particles. In at least one embodiment, the coating comprises a polymeric material.

[0010] In a further aspect of the present disclosure, a system for reducing or preventing froth formation in a gas-liquid contactor comprises: a flow bottleneck; a region of gas-liquid contact within the flow bottleneck; and a device comprising at least one superwettable surface.

[0011] In at least one embodiment, the region of gas-liquid contact comprises a bubblecontaining liquid. In at least one embodiment, the bubble-containing fluid comprises a solvent.

[0012] In at least one embodiment, the region of gas-liquid contact comprises a gas. In at least one embodiment, the gas-liquid contactor comprises at least one of a distillation column,Docket No. 28482-1335 separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, or reactor agitator.

[0013] In at least one embodiment, the device comprises a superwettable surface. In at least one embodiment, the superwettable surface comprises a hydrophobic surface. In at least one embodiment, the superwettable surface comprises a hierarchical structure. In at least one embodiment, the hierarchical structure includes ridges, pores, spikes, and / or posts.

[0014] In at least one embodiment, the superwettable surface is achieved via a coating. In at least one embodiment, the coating comprises a binder. In at least one embodiment, the coating comprises a layer of hydrophobized particles.

[0015] In at least one embodiment, the device forms a surface of at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, or reactor agitator. In at least one embodiment, the device floats on a liquid surface of the region of gas-liquid contact. In at least one embodiment, the device comprises a mesh or grid installed in the region of gas-liquid contact.BRIEF DESCRIPTION OF DRAWINGS

[0016] The disclosure described herein is illustrated by way of example and not by way of limitation in the accompanying figures.

[0017] FIG. 1 shows a Kriiss foam analyzer evaluating the froth prevention capabilities of coated and uncoated devices.

[0018] FIG. 2 shows a custom-built lab system for froth analysis used to evaluate the foam prevention capabilities of coated and uncoated devices.

[0019] FIG. 3 A demonstrates the evaluation of the froth reduction and prevention capabilities of a 16” coated mesh.

[0020] FIG. 3B demonstrates normalized effects of the coated mesh on foaming behavior.

[0021] FIG. 4 demonstrates the evaluation of the froth reduction and prevention capabilities of a coated random and polyethylene beads.

[0022] FIG. 4B demonstrates normalized effects of the coated beads on foaming behavior.DEFINITIONS

[0023] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent withDocket No. 28482-1335 their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0024] As used herein, a surface is said to be “superwettable” towards the gas phase if a bubble of such gas phase, when placed on the surface immersed in a liquid, exhibits a contact angle lower than 30 degrees. Superwettability can be achieved, for example, by chemical modification of a surface, by incorporating microscopic physical structures into the surface, or by a combination thereof. Examples of superwettable modifications include, but are not limited to, the grafting of hydrophilic polymer brushes onto the surface, plasma treatment to introduce polar functional groups, deposition of nanostructured coatings such as silica or titania nanoparticles, and the application of self-assembled monolayers bearing hydrophilic moieties. Additionally, surfaces may be rendered superwettable by etching or patterning to create hierarchical micro- and nano-scale roughness, or by coating with amphiphilic molecules that promote strong affinity for the liquid phase and thus enhance gas-phase wettability.

[0025] As used herein, the singular forms “a,” “an,” and “the” include plural references unless the context clearly indicates otherwise. Thus, for example, reference to “a component” includes a single component as well as a mixture of two or more similar or different components, and the like.

[0026] As used herein, the term “of’ may mean “comprising.” For example, “a liquid dispersion of’ may be interpreted as “a liquid dispersion comprising.”

[0027] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Additionally, as used herein, “or” means “and / or.”

[0028] As used herein, the term “about” or “approximately” in connection with a measured quantity, refers to the normal variations in that measured quantity, as expected by one of ordinary skill in the art in making the measurement and exercising a level of care commensurate with the objective of measurement and the precision of the measuring equipment. In certain embodiments, the term “about” includes the recited number ±10%, such that “about 10” would include from 9 to 11.

[0029] Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to illuminate certain materials and methods and does not pose a limitation on scope. No languageDocket No. 28482-1335 in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosed materials and methods.

[0030] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrase “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. In addition, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or.”DETAILED DESCRIPTION

[0031] Embodiments of the present disclosure relate to methods for reducing or preventing froth formation in gas-liquid contactor devices, and devices and components thereof configured for the same. Specifically, certain embodiments advantageously address the drawbacks of excessive frothing in these gas-liquid contactors by the use froth reduction devices. In certain embodiments, features of these devices can include, but are not limited to: (i) the presence of a surface modification that promotes froth reduction, and (ii) positioning of froth reducing components in the appropriate region within the contactor where froth bottlenecks are created.

[0032] The introduction of devices for froth reduction and prevention that are adapted to existing reactor structures eliminates the need for expensive redesign of reactors to implement strategies such as larger reactor volumes to accommodate froth volume, or the use of mechanical defoamers. These devices also remove the need for chemical anti-froth additives that jeopardize product purity and may accelerate catalyst fouling.

[0033] In at least one embodiment, the method enables reducing or preventing froth formation in chemical reactor bottlenecks without the use of chemical additives or extensive modification of existing reactor structures. The method includes contacting a region of gas-liquid contact within a flow bottleneck with a device. The device includes at least one superwettable surface adapted to reduce or prevent froth formation at the region of the gas-liquid contact.

[0034] The drainage of the liquid film between gas bubbles and subsequent bubble coalescence are important factors for controlling froth stability. Rapid bubble burst due to fast drainage of the liquid film between gas bubbles and surfaces with bio-inspired superwettability towards the gas phase has been demonstrated. For the present embodiments, this concept of superwettability towards the gas phase is used to convey froth reduction properties to a surface, which is localized in the appropriate region of a gas-liquid contactor where, upon contact with the gas-liquid mixture, the modified surface acts to mitigate the negative impacts of excessive frothing. In the specific case of trayed columns, for example, excessive frothing normally leadsDocket No. 28482-1335 to a bottleneck in the downcomers. To address this scenario, certain embodiments may utilize the modified surface material in the downcomer walls.

[0035] Another problem facing trayed columns is premature jet flooding due to excessive frothing. To address this scenario, certain embodiments may utilize the modified surface material in the bottom part of the trays and on the walls of the column in the space between trays. For packed columns, issues from excessive frothing typically start at the bottom of the beds. To address this scenario, certain embodiments may utilize the modified surface material to construct the packing support grids, as well as at least a portion of the packing at the bottom of the beds. Liquid distributors can also show bottlenecks in packed columns due to excessive frothing. In this scenario, either the walls of the distributor can be made with the modified surface material, and floating devices with the modified surface material can be added to the distributor. For stirred tanks, bottlenecks from excessive frothing are found in the upper part of the vessel. Thus, either the addition of floating devices containing the modified surface material to the system or the installation of a mesh or grid containing the modified surface in the upper part of the vessel can be used to reduce or eliminate frothing.

[0036] In an embodiment of the present disclosure, a method for reducing or preventing froth formation in a gas-liquid contactor has been developed. The method includes contacting a region of gas-liquid contact within a flow bottleneck with a device. The device may further include at least one superwettable surface adapted to reduce or prevent froth formation at the region of the gas-liquid contact.

[0037] The embodiments described herein offer several advantages over conventional methods for managing froth formation in gas-liquid contactors. By utilizing devices with superwettable surfaces, these methods can effectively reduce or prevent the accumulation of froth, thereby minimizing operational bottlenecks and improving process efficiency. The use of modified surface materials in distributor walls, floating devices, or mesh installations provides a versatile approach that can be tailored to various vessel geometries and process conditions. Additionally, these embodiments can enhance the reliability and longevity of equipment by reducing the risk of overflow, blockages, and associated maintenance requirements.

[0038] In at least one embodiment, the region of gas-liquid contact may include a bubblecontaining liquid. As used herein, the term “bubble” is given its ordinary meaning in the art and refers to a gaseous phase surrounded by a liquid. Bubbles can have any suitable shape such as spherical, deviational from spherical, or ellipsoidal, and are found at the interface of the bubblecontaining liquid and another fluid.Docket No. 28482-1335

[0039] In at least one embodiment, the bubble-containing liquid may be a froth. As used herein, the term “froth” is given their ordinary meanings in the art and refer to an accumulation of a plurality of pockets of entrapped gas.

[0040] In at least one embodiment, the bubble-containing liquid may include a solvent. For example, the solvent may include an oil, an organic solvent, and / or water. Examples of organic solvents that may be present in gas-liquid contactors include, but are not limited to, methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, toluene, xylene, hexane, heptane, cyclohexane, dichloromethane, chloroform, ethyl acetate, and dimethyl sulfoxide (DMSO). The selection of a particular organic solvent may depend on the specific process requirements, solubility characteristics, and compatibility with other process materials.

[0041] In at least one embodiment, the region of gas-liquid contact may include a gas. For example, the gas may include a plurality of gases. In at least one embodiment, the gas may include at least one of a gaseous hydrocarbon, N2, O2, CO, He, H2, CO2, Ar, and / or a combination thereof. In at least one embodiment, the gas may be air (e.g., the combination of primarily N2 and O2).

[0042] In at least one embodiment, the gaseous hydrocarbon may include at least one of an organic compound with up to four carbon atoms. In at least one embodiment, the organic compound may be branched, linear, or a combination thereof. In at least one embodiment, the organic compound may be saturated or unsaturated.

[0043] In at least one embodiment, the gas-liquid contactor may include at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, man way, or reactor agitator. In at least one embodiment, any of the aforementioned gas-liquid contactors may include bottleneck regions or constricted flow areas where froth formation is likely to occur. These bottleneck regions can arise due to design features such as tray spacing, packing density, or the presence of internal structures that restrict the flow of gas or liquid. The accumulation of froth in these regions can impede mass transfer efficiency, increase pressure drop, and potentially lead to operational challenges such as flooding or entrainment.

[0044] In at least one embodiment, a downcomer is adapted to separate liquid hydrocarbons from the gas phase and divert the liquid hydrocarbons to a liquid phase compartment.

[0045] In at least one embodiment, a column may further include stirred columns, bubble columns, stirred reactors, or extraction columns.

[0046] In at least one embodiment, a column may further include a vessel with an exchange tray.Docket No. 28482-1335

[0047] In at least one embodiment, a column may be packed with different packings such as saddles, rings (e.g., Raschig rings), or beads.

[0048] In at least one embodiment, the device may form a surface of at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, man way, or reactor agitator.

[0049] In at least one embodiment, the device may be a free-standing floatation device adapted to float on a liquid surface of the region of gas-liquid contact.

[0050] In at least one embodiment, the floatation device may be a floating body. In at least one embodiment, a floating body is a body that is buoyant. In at least one embodiment, a floating body can swim above, under, or on the surface of a liquid. In at least one embodiment, the floating body may be constructed from materials selected for their buoyancy, chemical resistance, and mechanical strength. Suitable materials may include, but are not limited to, polymers such as polytetrafluoroethylene (PTFE), polypropylene, polyethylene, or polyvinylidene fluoride (PVDF). In further embodiments, composite materials or foamed plastics may be used to reduce weight while maintaining structural integrity.

[0051] In at least one embodiment, the device may include a mesh or grid installed in the region of gas-liquid contact. In at least one embodiment, the mesh or grid may be fabricated from materials selected for their durability, chemical resistance, and compatibility with the process environment. Suitable materials may include stainless steel, titanium, or corrosionresistant alloys, as well as high-performance polymers such as PTFE, PVDF, or polypropylene. The mesh or grid may be constructed with a range of opening sizes, for example, with apertures ranging from about 0.1 millimeters to about 10 millimeters, depending on the desired level of gas-liquid interaction and the characteristics of the froth to be managed. The thickness of the grid elements may range from about 0.2 millimeters to about 5 millimeters to provide sufficient mechanical strength while minimizing flow obstruction. In some embodiments, the grid may be formed as a woven mesh, a perforated plate, or a lattice structure, and may be configured in a planar or contoured shape to conform to the geometry of the gas-liquid interface. The grid may be supported by a frame or floatation elements to maintain its position at or near the surface of the liquid. In certain embodiments, the surface of the mesh or grid may be treated or coated to enhance its wettability or to impart anti-fouling properties.

[0052] In at least one embodiment, the reduction or prevention of froth formation may include merging the gas contained within the froth with the gas of the region of gas-liquid contact.

[0053] In at least one embodiment, the superwettable surface may include a hydrophobic surface. For example, the superwettable surface may further include a surface that isDocket No. 28482-1335 amphiphobic or super-amphiphobic. In at least one embodiment, the superwettable surface may be achieved through chemical modification of the substrate. For example, in at least one embodiment, the surface may be functionalized with silane-based compounds, such as perfluorooctyltrichlorosilane (PFOTS) or hexamethyldisilazane (HMDS), to impart hydrophobic or amphiphobic properties. In at least one embodiment, the surface may be treated with polydimethylsiloxane (PDMS) or fluoropolymer coatings to enhance water and oil repellency. In some embodiments, plasma treatment or grafting of polymer brushes, such as polyethylene glycol (PEG) or polyvinylidene fluoride (PVDF), may be employed to tailor the surface energy and wettability characteristics.

[0054] In at least one embodiment, the superwettable surface may include a hierarchical structure. For example, the hierarchical structure may include ridges, pores, spikes, and / or posts. In at least one embodiment, the hierarchical structure may include a nano-structured surface. For example, the nano-structured surface may comprise arrays of nanopillars, nanowires, nanocones, or nanogrooves. Representative feature dimensions for such nano-structured surfaces may include pillar or wire diameters ranging from about 10 nanometers to about 500 nanometers, heights from about 50 nanometers to about 2 micrometers, and inter-feature spacings from about 20 nanometers to about 1 micrometer. Such nano-structured features may be fabricated using techniques such as lithography, etching, or self-assembly-based approaches.

[0055] In at least one embodiment, the superwettable surface may include a coating. For example, the coating may further include silica and acetone.

[0056] In at least one embodiment, the coating may include a binder. In at least one embodiment, the binder may include one or more solvent components selected from toluene, benzene, xylenes, t-butyl acetate, acetone, and polymers constituents such as epoxy-amines, epoxy-amine 2K systems, isocyanates, fluorinated polymers, acrylic polymers, functionalized silicones. In at least one embodiment, the coating may include a layer of hydrophobized particles.

[0057] In at least one embodiment, the hydrophobized particles may include bare pyrogenic silica, amino-functionalized silica, amino- and alkyl-functionalized silica, amino- and perfluoroalkyl-functionalized silica, siliconized particles, silicone particles, or glycidyl variations.

[0058] In another embodiment, a system for reducing or preventing the froth formation in a gas-liquid contactor has been developed. The system may include a flow bottleneck, a region of gas-liquid contact with the flow bottleneck, and a device that may include at least one superwettable surface. The device may correspond to any of the embodiments described above.Docket No. 28482-1335

[0059] In at least one embodiment, the region of gas-liquid contact may include a bubblecontaining liquid.

[0060] In at least one embodiment, the bubble-containing liquid may include a solvent, such as an oil, an organic solvent, and / or water.

[0061] In at least one embodiment, the region of gas-liquid contact may include a gas. In at least one embodiment, the gas phase may include a plurality of gases. In at least one embodiment, the gas may include at least one of a gaseous hydrocarbon, N2, O2, CO, He, H2, CO2, Ar, CI2, organic volatiles including hydrocarbons and oxygenates, NOx, and / or a combination thereof. In at least one embodiment, the gas may be air (e.g., the combination of primarily N2 and O2).

[0062] In at least one embodiment, the gaseous hydrocarbon may include at least one of an organic compound with up to four carbon atoms. In at least one embodiment, the organic compound may be branched, linear, or a combination thereof. In at least one embodiment, the organic compound may be saturated or unsaturated.

[0063] In at least one embodiment, the gas-liquid contactor may include at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, man way, reflux, liquid feed, or reactor agitator.

[0064] In at least one embodiment, a downcomer is adapted to separate liquid hydrocarbons from the gas phase and divert the liquid hydrocarbons to a liquid phase compartment.

[0065] In at least one embodiment, a column may further include stirred columns, bubble columns, reactions columns, or extraction columns.

[0066] In at least one embodiment, a column may be packed with different packings such as saddles, Raschig, rings, or beads.

[0067] In at least one embodiment, the device may include a superwettable surface.

[0068] In at least one embodiment, the superwettable surface may include a hydrophobic surface.

[0069] In at least one embodiment, the superwettable surface may further include a surface that is amphiphobic or super-amphiphobic.

[0070] In at least one embodiment, the superwettable surface may include a hierarchical structure.

[0071] In at least one embodiment, the hierarchical structure may include ridges, pores, spikes, and / or posts.

[0072] In at least one embodiment, the superwettable surface may be achieved via a coating.

[0073] In at least one embodiment, the coating may further include silica and acetone.

[0074] In at least one embodiment, the coating may include a binder.Docket No. 28482-1335

[0075] In at least one embodiment, the binder may include xylenes, t-butyl acetate, and acetone.

[0076] In at least one embodiment, the coating may include a layer of hydrophobized particles.

[0077] In at least one embodiment, the hydrophobized particles may include bare pyrogenic silica, amino-functionalized silica, amino- and alkyl-functionalized silica, amino- and perfluoroalkyl-functionalized silica, or glycidyl variations.

[0078] In at least one embodiment, the device may float on a liquid surface of the region of gas-liquid contact.

[0079] In at least one embodiment, the device may include a mesh or grid installed in the region of gas-liquid contact.

[0080] The following exemplary embodiments are now described.

[0081] Embodiment 1 : A method for reducing or preventing froth formation in a gas-liquid contactor comprising: contacting a region of gas-liquid contact within a flow system with a device comprising at least one superwettable surface adapted to reduce or prevent froth formation at a location of the gas-liquid contact.

[0082] Embodiment 2: The method of Embodiment 1, wherein the region of gas-liquid contact comprises a bubble-containing liquid.

[0083] Embodiment 3: The method of Embodiment 2, wherein the bubble-containing liquid comprises a solvent.

[0084] Embodiment 4: The method of any one of Embodiments 1-3, wherein the region of gas-liquid contact contains a flow bottleneck.

[0085] Embodiment 5: The method of any one of Embodiments 1-4, wherein the region of gas-liquid contact comprises a gas.

[0086] Embodiment 6: The method of any one of Embodiments 1-5, wherein the gas and / or the liquid is in a continuous flow system and the location of the gas-liquid contact may also be variable.

[0087] Embodiment 7: The method of any one of Embodiments 1-6, wherein the gas-liquid contactor comprises at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, reactor agitator, or tank vent.

[0088] Embodiment 8: The method of any one of Embodiments 1-7, wherein the device forms a surface of at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, reactor agitator, or tank vent.Docket No. 28482-1335

[0089] Embodiment 9: The method of any one of Embodiments 1-8, wherein the device is a free-standing flotation device adapted to float on a liquid surface of the region of gas-liquid contact.

[0090] Embodiment 10: The method of any one of Embodiments 1-9, wherein the device comprises a mesh or grid installed in the region of gas-liquid contact.

[0091] Embodiment 11 : The method of any one of Embodiments 1-10, wherein the superwettable surface comprises a hydrophobic surface.

[0092] Embodiment 12: The method of Embodiment 11, wherein the hydrophobic surface is a superhydrophobic surface.

[0093] Embodiment 13: The method of any one of Embodiments 1-12, wherein the superwettable surface comprises a hierarchical structure.

[0094] Embodiment 14: The method of Embodiment 13, wherein the hierarchical structure includes ridges, pores, spikes, posts, and / or other patterns that may contribute to surface roughness.

[0095] Embodiment 15: The method of any one of Embodiments 1-14, wherein the superwettable surface comprises a coating.

[0096] Embodiment 16: The method of Embodiment 15, wherein the coating comprises a binder comprising one or more solvent components selected from toluene, benzene, xylenes, t- butyl acetate, acetone, and polymers constituents such as epoxy-amines, epoxy-amine 2K systems, isocyanates, fluorinated polymers, acrylic polymers, or functionalized silicones.

[0097] Embodiment 17: The method of Embodiment 15, wherein the coating comprises a layer of hydrophobized particles.

[0098] Embodiment 18: A system for reducing or preventing froth formation in a gas-liquid contactor, the system comprising: a flow system; a region of gas-liquid contact within a flow bottleneck; and a device comprising at least one superwettable surface.

[0099] Embodiment 19: The system of Embodiment 18, wherein the region of gas-liquid contact comprises a bubble-containing liquid.

[0100] Embodiment 20: The system of Embodiment 19, wherein the bubble-containing liquid comprises a solvent.

[0101] Embodiment 21 : The system of any one of Embodiments 18-20, wherein the region of gas-liquid contact comprises a gas.

[0102] Embodiment 22: The system of any one of Embodiments 18-20, wherein the gasliquid contactor comprises at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, or reactor agitator.Docket No. 28482-1335

[0103] Embodiment 23: The system of any one of Embodiments 18-20, wherein the device comprises a superwettable surface.

[0104] Embodiment 24: The system of Embodiment 23, wherein the superwettable surface comprises a hydrophobic surface.

[0105] Embodiment 25: The system of either Embodiment 23 or Embodiment 24, wherein the superwettable surface comprises a hierarchical structure.

[0106] Embodiment 26: The system of any one of Embodiments 23-25, wherein the hierarchical structure includes ridges, pores, spikes, and / or posts.

[0107] Embodiment 27: The system of any one of Embodiments 23-26, wherein the superwettable surface is achieved via a coating.

[0108] Embodiment 28: The system of Embodiment 27, wherein the coating comprises a binder.

[0109] Embodiment 29: The system of either Embodiment 27 or Embodiment 28, wherein the coating comprises a layer of hydrophobized particles.

[0110] Embodiment 30: The system of any one of Embodiments 18-29, wherein the device forms a surface of at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, reactor agitator, or tank vent.[oni] Embodiment 31 : The system of any one of Embodiments 18-30, wherein the device floats on a liquid surface of the region of gas-liquid contact.

[0112] Embodiment 32: The system of any one of Embodiments 18-31, wherein the device comprises a mesh or grid installed in the region of gas-liquid contact.ILLUSTRATIVE EXAMPLES

[0113] The following examples are set forth to assist in understanding the disclosure and should not be construed as specifically limiting the invention described and claimed herein.Such variations of the invention, including the substitution of all equivalents now known or later developed, which would be within the purview of those skilled in the art, and changes in formulation or minor changes in experimental design, are to be considered to fall within the scope of the invention incorporated herein.

[0114] Studies were conducted to analyze froth reduction and prevention in systems with coated and uncoated devices subjected to conditions of varied solvent, flow rate, vessel diameter, and liquid volume.Example 1 and Comparative Example 1Docket No. 28482-1335

[0115] A study was conducted to analyze froth reduction and prevention of a coated device. Comparative Example 1 was prepared having 80 mL of an aqueous solution of Texapon N70 (an anionic surfactant) with a concentration of 100 ppm (weight basis), 12 L / hour N2, a 35 mm diameter chamber, and 3.5 mm / s superficial flow velocity using an uncoated device. Example 1 was using the same conditions having a coated device formed using a commercially available superhydrophobic coating. The study was performed by feeding the same N2 gas flow to both Example 1 and Comparative Example 1. The performance comparison was demonstrated in FIG. 1. Both samples were analyzed by the Kriiss foam analyzer DFA 100. As is illustrated in FIG. 1, with the same volume of fluid and gas flow rates, the coated device demonstrated significantly fewer bubbles and frothing than the uncoated device.Example 2

[0116] A study was conducted to analyze froth reduction and prevention of a coated device. Example 2 was prepared having 150 mL of liquid, 8 L / h N2, a 55 mm diameter chamber, and 0.9 mm / s superficial flow velocity using an uncoated device. The study was performed by feeding N2 gas flow to Example 2 using the custom-built lab system of FIG. 2 for analyzing froth mitigation.Example 3 and Comparative Example 3

[0117] A study was conducted to analyze froth reduction and prevention of a coated device. Example 3 was analyzed using the Kriiss foam analyzer with 100 ppm Texapon N70 in water. Comparative Example 3 was prepared using a 16” uncoated mesh. Example 3 was prepared using a 16” mesh dip-coated with a commercially available superhydrophobic composition (Ultra Ever Dry®). The study was performed by feeding the same N2 gas flow to both Example 3 and Comparative Example 3. The performance comparison after stopping the gas flow was demonstrated by the visuals in FIGS. 3A and 3B. As is shown in FIG. 3A, with the same volume of fluid and gas flow rates, the coated mesh demonstrated significantly reduces the froth height in comparison to the uncoated mesh. As is illustrated in FIG. 3B, the coated mesh demonstrated the ability to both prevent the formation of froth as represented by the antifoaming measurement (top), as well as froth reduction as represented by the red defoaming measurement as froth height after 10 minutes (bottom).Example 4 and Comparative Example 4Docket No. 28482-1335

[0118] A study was conducted to analyze froth reduction and prevention of a coated device. Example 4 was analyzed using custom-built lab system with 100 ppm Texapon N70 in water. Comparative Example 4 was prepared using packing bodies and PE beads. Example 4 was prepared using superhydrophobic coated (Ultra Ever Dry®, “UED”) packing bodies and polyethylene (PE) beads. The study was performed by feeding the same N2 gas flow to both Example 4 and Comparative Example 4. The performance comparison after stopping the gas flow is shown in FIGS. 4A and 4B. As is illustrated in Figure 4A, with the same volume of fluid and gas flow rates, both the coated packing bodies and PE beads demonstrated significantly reduced froth height in comparison to the uncoated materials. As is illustrated in Figure 4B, the coated materials demonstrated the ability to both prevent the formation of froth as represented by the antifoaming measurement (top), as well as froth reduction as represented by the defoaming measurement (bottom) as froth height after 60 minutes.

[0119] For simplicity of explanation, the embodiments of the methods of this disclosure are depicted and described as a series of acts. However, acts in accordance with this disclosure can occur in various orders and / or concurrently, and with other acts not presented and described herein. Furthermore, not all illustrated acts may be required to implement the methods in accordance with the disclosed subject matter. In addition, those skilled in the art will understand and appreciate that the methods could alternatively be represented as a series of interrelated states via a state diagram or events.

[0120] In the foregoing description, numerous specific details are set forth, such as specific materials, dimensions, processes parameters, etc., to provide a thorough understanding of the present invention. The particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments. The words “example” or “exemplary” are used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as “example” or “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects or designs. Rather, use of the words “example” or “exemplary” is intended to present concepts in a concrete fashion. As used in this application, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or”. That is, unless specified otherwise, or clear from context, “X includes A or B” is intended to mean any of the natural inclusive permutations. That is, if X includes A; X includes B; or X includes both A and B, then “X includes A or B” is satisfied under any of the foregoing instances. Reference throughout this specification to “an embodiment”, “certain embodiments”, or “one embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrase “anDocket No. 28482-1335 embodiment”, “certain embodiments”, or “one embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment.

[0121] The present disclosure has been described with reference to specific exemplary embodiments thereof. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. Various modifications of the disclosure in addition to those shown and described herein will become apparent to those skilled in the art and are intended to fall within the scope of the appended claims.

Claims

Docket No. 28482-1335What is claimed is:

1. A method for reducing or preventing froth formation in a gas-liquid contactor comprising: contacting a region of gas-liquid contact within a flow system with a device comprising at least one superwettable surface adapted to reduce or prevent froth formation at a location of the gas-liquid contact.

2. The method of claim 1, wherein the region of gas-liquid contact comprises a bubblecontaining liquid.

3. The method of claim 2, wherein the bubble-containing liquid comprises a solvent.

4. The method of claim 1, wherein the region of gas-liquid contact contains a flow bottleneck.

5. The method of claim 1, wherein the region of gas-liquid contact comprises a gas.

6. The method of claim 1, wherein the gas and / or the liquid is in a continuous flow system and the location of the gas-liquid contact may also be variable.

7. The method of claim 1, wherein the gas-liquid contactor comprises at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, reactor agitator, or tank vent.

8. The method of claim 1, wherein the device forms a surface of at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, reactor agitator, or tank vent.

9. The method of claim 1, wherein the device is a free-standing flotation device adapted to float on a liquid surface of the region of gas-liquid contact.

10. The method of claim 1, wherein the device comprises a mesh or grid installed in the region of gas-liquid contact.Docket No. 28482-133511. The method of claim 1, wherein the superwettable surface comprises a hydrophobic surface.

12. The method of claim 11, wherein the hydrophobic surface is a superhydrophobic surface.

13. The method of claim 1, wherein the superwettable surface comprises a hierarchical structure.

14. The method of claim 13, wherein the hierarchical structure includes ridges, pores, spikes, posts, and / or other patterns that may contribute to surface roughness.

15. The method of claim 1, wherein the superwettable surface comprises a coating.

16. The method of claim 15, wherein the coating comprises a binder comprising one or more solvent components selected from toluene, benzene, xylenes, t-butyl acetate, acetone, and polymers constituents such as epoxy-amines, epoxy-amine 2K systems, isocyanates, fluorinated polymers, acrylic polymers, or functionalized silicones.

17. The method of claim 15, wherein the coating comprises a layer of hydrophobized particles.

18. A system for reducing or preventing froth formation in a gas-liquid contactor, the system comprising: a flow system; a region of gas-liquid contact within a flow bottleneck; and a device comprising at least one superwettable surface.

19. The system of claim 18, wherein the region of gas-liquid contact comprises a bubblecontaining liquid.

20. The system of claim 19, wherein the bubble-containing liquid comprises a solvent.

21. The system of claim 18, wherein the region of gas-liquid contact comprises a gas.Docket No. 28482-133522. The system of claim 18, wherein the gas-liquid contactor comprises at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, or reactor agitator.

23. The system of claim 18, wherein the device comprises a superwettable surface.

24. The system of claim 23, wherein the superwettable surface comprises a hydrophobic surface.

25. The system of claim 23, wherein the superwettable surface comprises a hierarchical structure.

26. The system of claim 25, wherein the hierarchical structure includes ridges, pores, spikes, and / or posts.

27. The system of claim 23, wherein the superwettable surface is achieved via a coating.

28. The system of claim 27, wherein the coating comprises a binder.

29. The system of claim 27 wherein the coating comprises a layer of hydrophobized particles.

30. The system of claim 18, wherein the device forms a surface of at least one of a distillation column, separation column, tray absorber, stripper, quench tower, stirred vessel, distributor, downcomer, reactor vent, reactor agitator, or tank vent.

31. The system of claim 18, wherein the device floats on a liquid surface of the region of gasliquid contact.

32. The system of claim 18, wherein the device comprises a mesh or grid installed in the region of gas-liquid contact.

Images