Abstract: Cations that can precipitate from an aqueous composition to produce scaling are sequestered by adding a multi-dentate ligand to the aqueous composition. The multi-dentate ligand bonds with the cation to form a non-scaling ionic complex; and the aqueous solution with the ionic complex is used in a process that produces substantially pure water from the aqueous composition, where the cation, absent formation of the ionic complex, is subject to scaling. The pH of the aqueous composition (or a brine including components of the aqueous composition) is then reduced to release the cation from the multi-dentate ligand; and the multi-dentate ligand, after the cation is released, is then reused in a predominantly closed loop.

Abstract: A method reuses produced water resulting from a fossil fuel extraction operation. The method includes providing the produced water as an input to an electrodialysis system. The method also includes running the electrodialysis system to produce a diluate and a concentrate. The diluate is contaminated so as to have a conductivity of no less than 0.1 Siemens/meter. The method also includes reformulating the diluate to produce fossil fuel extraction fluid. The method also includes using the produced fossil fuel extraction fluid in the fossil fuel extraction operation. An electrodialysis system includes first and second stacks. The electrodialysis system also includes first and second voltage sources, coupled to the first and second stacks, so as to apply a first voltage to the first stack lower by at least about 10% than a second voltage to the second stack.

Abstract: A liquid purification system includes a filter system having a set of filters with a feed stream, a concentrate stream, and a permeate stream. The feed stream constitutes an input to the liquid purification system. The liquid purification system also includes an electrodialysis system having at least one stack of at least one pair of electrodes, between which is disposed at least one cell pair having an anion exchange membrane and a cation exchange membrane. The electrodialysis system includes a diluate inlet, a diluate outlet and a concentrate outlet. The diluate inlet is fluidly coupled to the concentrate stream and at least a portion of the diluate outlet is fluidly coupled to at least a portion of the permeate stream to produce a purified output stream. A ratio of electrical conductivity of the purified output stream to the feed stream is no less than about 0.55.

Abstract: A multi-effect membrane distillation system includes first and second membrane distillation effects. Each effect (stage) includes a feed channel, a gap, and a vapor-permeable membrane separating the feed channel from the gap. A liquid feed is fed into the feed channel of the first effect via a feed inlet, and the liquid feed is extracted from the first-stage feed channel via a first feed-transfer conduit that delivers the liquid feed to the second-stage feed channel. The feed is extracted from the second-stage feed channel via a second feed-transfer conduit. At least one permeate-extraction conduit is coupled with the first-stage and second-stage gaps and is configured to extract permeate (e.g., pure water) therefrom.

Abstract: The wastewater filtration system and method relates to systems and methods that use Ruba Al-Khali Saudi sand as the filtration media in systems for treating industrial wastewater. Ruba Al-Khali Saudi sand is effective in removing organic dyes, particularly rhodamine B, from the wastewater. The method includes bringing wastewater having an organic dye constituent into contact with the Saudi sand for a period of time sufficient to adsorb the organic dye. The system may include a batch reactor, such as a fixed bed or moving bed reactor, or a continuous flow reactor, such as a column reactor. When a batch reactor is used, the method may benefit from shaking or agitating the filtration media, particularly in the dark or under low ambient light conditions. The method may include regenerating the Saudi sand after use by heating the filtration media.

Abstract: An apparatus for enhanced anti-fouling of a submerged surface includes a bath of a feed liquid that includes water; a fouling structure in contact with the feed liquid; and a gas feed configured to introduce a gas into contact with the fouling structure and the feed liquid to separate the fouling structure from the feed liquid with a gas layer.

Abstract: A multi-stage bubble-column vapor mixture condenser comprises at least a first stage and a second stage. Each stage includes a carrier-gas inlet and a carrier-gas outlet, as well as a condenser chamber containing a condensing bath in fluid communication with the carrier-gas inlet and the carrier-gas outlet. The carrier-gas inlet is positioned to bubble carrier gas from the carrier-gas inlet up through the condensing bath, overcoming a hydrostatic head of the condensing bath. The carrier-gas outlet is positioned with an opening for carrier-gas extraction above the condensing bath, wherein the first-stage carrier-gas outlet is in fluid communication with the carrier-gas inlet of the second stage to facilitate flow of the carrier gas through the condensing bath in the condenser chamber of the first stage and then through the condensing bath in the condenser chamber of the second stage.

Abstract: A carrier-gas mixture is directed through a fluid flow path in a combined heat and mass transfer device, which can be operated at sub-atmospheric pressure. Heat and mass are transferred from or to the carrier-gas mixture via interaction with a liquid composition that includes a vaporizable component in a liquid state to substantially change the content of the vaporizable component in the carrier-gas mixture via evaporation or condensation. The mass flow rate of the carrier-gas mixture is varied by extracting or injecting the carrier-gas mixture from at least one intermediate location in the fluid flow path, and/or the mass flow rate of the liquid composition is varied by extracting or injecting the liquid composition from at least one intermediate location in the fluid flow path; and the flow of the carrier-gas mixture or the liquid composition is regulated to reduce the average local enthalpy pinch in the device.

Abstract: A carrier gas and a combined feed liquid are directed through a humidifier, where water vaporizes from the combined feed liquid into the carrier gas, and through a dehumidifier, where the combined feed liquid cools the carrier gas to condense water from the carrier gas. At least a portion of the concentrated brine stream from the humidifier is directed through a pressure-retarded osmosis unit, while an initial feed solution is directed, in counter-flow, through the osmosis unit. Water from the initial feed solution flows through a membrane in the osmosis chamber into the concentrated brine stream to dilute and increase the volumetric flow rate of the brine stream. The diluted brine stream is extracted from the osmosis chamber and depressurized to produce power, while the concentrated initial feed solution is combined with the depressurized, diluted brine stream to form the combined feed liquid.

Abstract: A multi-stage bubble-column vapor mixture condenser comprises at least a first stage and a second stage. Each stage includes a carrier-gas inlet and a carrier-gas outlet, as well as a condenser chamber containing a condensing bath in fluid communication with the carrier-gas inlet and the carrier-gas outlet. The carrier-gas inlet is positioned to bubble carrier gas from the carrier-gas inlet up through the condensing bath, overcoming a hydrostatic head of the condensing bath. The carrier-gas outlet is positioned with an opening for carrier-gas extraction above the condensing bath, wherein the first-stage carrier-gas outlet is in fluid communication with the carrier-gas inlet of the second stage to facilitate flow of the carrier gas through the condensing bath in the condenser chamber of the first stage and then through the condensing bath in the condenser chamber of the second stage.

Abstract: Concentration control in filtration systems and associated methods are generally described. Streams originating from upstream filters and having similar concentrations of a target minor component and/or similar osmotic pressures can be mixed and subsequently filtered within additional filters. Certain embodiments comprise recycling an output stream produced by a filter to a filter feed stream, wherein the output stream and the filter feed stream have similar concentrations of a target minor component and/or similar osmotic pressures. Such strategic mixing and/or recycling can reduce the amount of energy and/or the amount of filtration medium surface area required to achieve a desired concentration of the target minor component in a final product stream.

Abstract: Flow control in multi-step filtration systems and associated methods are generally described. Certain embodiments are related to methods in which a single filter is used to perform multiple, separate filtration steps. In some cases, a diluted permeate from a first filtration step can be recycled back through the filter, as part of a separate filtration step, to produce a second retentate and a second permeate. Subsequent filtration steps can also be performed. Systems configured to perform multiple, separate filtration steps using a single filter are also described.

Abstract: Filtration systems in which the ratios of minor components in mixtures can be balanced, and associated methods, are generally described. Certain embodiments are related to methods in which a portion of a retentate stream produced by filtering an initial liquid feed during a first filtration step is mixed with the permeate produced by filtering the permeate from the first filtration step. In some cases, the amount of the first retentate that is mixed with the second permeate is selected such that the ratios of the minor components within the final retentate and permeate streams produced by the filtration system are similar to the ratio of the minor components within the initial liquid. By maintaining similar ratios of minor components, according to certain embodiments, the flavor profile of the initial liquid mixture can be substantially maintained in the concentrated and diluted streams produced by the filtration system.

Abstract: A humidification-dehumidification system comprises a source of liquid; a humidifier including carrier-gas and liquid inlets and outlets and a chamber in which the liquid can contact a carrier gas containing a condensable fluid in vapor phase that is introduced from the carrier-gas inlet in a counterflow arrangement and in which a portion of the liquid can vaporize into the carrier gas; a bubble-column vapor mixture condenser including at least first and second stages, each stage including a carrier-gas inlet and outlet and a chamber configured to contain a liquid bath in fluid communication with the carrier-gas inlet and the carrier-gas outlet; a conduit passing from the source of the liquid through the chamber of each stage of the bubble-column condenser; and an intermediate exchange conduit coupled with (a) the bubble-column vapor mixture condenser and (b) the humidifier chamber at intermediate stages of each for transfer of the carrier gas therebetween.

Abstract: An energy-efficient liquid-gap distillation apparatus includes a source of a feed liquid; a distillation module comprising: (a) a feed-liquid chamber n fluid communication with the feed-liquid source to establish a flow of the feed liquid there through, wherein the feed-liquid chamber includes a selectively porous material that allows a component of the feed liquid to pass through the selectively porous material and exit the feed-liquid chamber in vapor form but not in liquid form; (b) a condensing surface maintained at a lower temperature than the feed liquid in the feed-liquid chamber, wherein the condensing surface is sufficiently hydrophobic to produce a contact angle with water of at least 150; and (c) a gap between the selectively porous material and the condensing surface. Vapor passing through the membrane can be condensed as jumping droplets at the condensing surface.

Abstract: Apparatus for energy-efficient conductive-gap membrane distillation includes a feed-liquid source and a distillation module. The distillation module includes a feed-liquid chamber in fluid communication with the feed-liquid source. The feed-liquid chamber includes a selectively porous material that allows a component of the feed liquid to pass through the selectively porous material and exit the feed-liquid chamber in vapor form but not in liquid form. The distillation module also includes a conductive-gap chamber adjacent to the selectively porous material on an opposite side of the selectively porous material from the feed-liquid chamber; a heat-transfer surface maintained at a lower temperature than the feed liquid in the feed-liquid chamber, wherein the heat-transfer surface is in thermal contact with the conductive-gap chamber; and a thermally conductive material extending across the conductive-gap chamber.

Abstract: A feed liquid flows into a second-stage humidifier chamber to form a second-stage humidifier bath. A first remnant of the feed liquid from the second-stage humidifier chamber then flows into a first-stage humidifier chamber to form a first-stage humidifier bath having a temperature lower than that of the second-stage bath. A second remnant of the feed liquid is then removed from the first-stage humidifier. Meanwhile, a carrier gas is injected into and bubbled through the first-stage humidifier bath, collecting a vaporizable component in vapor form from the first remnant of the feed liquid to partially humidify the carrier gas. The partially humidified carrier gas is then bubbled through the second-stage humidifier bath, where the carrier gas collects more of the vaporizable component in vapor form from the feed liquid to further humidify the carrier gas before the humidified carrier gas is removed from the second-stage humidifier chamber.

Abstract: A feed liquid flows into a second-stage humidifier chamber to form a second-stage humidifier bath. A first remnant of the feed liquid from the second-stage humidifier chamber then flows into a first-stage humidifier chamber to form a first-stage humidifier bath having a temperature lower than that of the second-stage bath. A second remnant of the feed liquid is then removed from the first-stage humidifier. Meanwhile, a carrier gas is injected into and bubbled through the first-stage humidifier bath, collecting a vaporizable component in vapor form from the first remnant of the feed liquid to partially humidify the carrier gas. The partially humidified carrier gas is then bubbled through the second-stage humidifier bath, where the carrier gas collects more of the vaporizable component in vapor form from the feed liquid to further humidify the carrier gas before the humidified carrier gas is removed from the second-stage humidifier chamber.

Abstract: A multi-stage bubble-column vapor mixture condenser comprises at least a first stage and a second stage. Each stage includes a carrier-gas inlet and a carrier-gas outlet, as well as a condenser chamber containing a condensing bath in fluid communication with the carrier-gas inlet and the carrier-gas outlet. The carrier-gas inlet is positioned to bubble carrier gas from the carrier-gas inlet up through the condensing bath, overcoming a hydrostatic head of the condensing bath. The carrier-gas outlet is positioned with an opening for carrier-gas extraction above the condensing bath, wherein the first-stage carrier-gas outlet is in fluid communication with the carrier-gas inlet of the second stage to facilitate flow of the carrier gas through the condensing bath in the condenser chamber of the first stage and then through the condensing bath in the condenser chamber of the second stage.

Abstract: A humidification-dehumidification system comprises a source of liquid; a humidifier including carrier-gas and liquid inlets and outlets and a chamber in which the liquid can contact a carrier gas containing a condensable fluid in vapor phase that is introduced from the carrier-gas inlet in a counterflow arrangement and in which a portion of the liquid can vaporize into the carrier gas; a bubble-column vapor mixture condenser including at least first and second stages, each stage including a carrier-gas inlet and outlet and a chamber configured to contain a liquid bath in fluid communication with the carrier-gas inlet and the carrier-gas outlet; a conduit passing from the source of the liquid through the chamber of each stage of the bubble-column condenser; and an intermediate exchange conduit coupled with (a) the bubble-column vapor mixture condenser and (b) the humidifier chamber at intermediate stages of each for transfer of the carrier gas therebetween.