Abstract: A method for condensing a vapor uses a multi-stage bubble-column vapor mixture condenser that includes at least a first stage, a second stage, and a third stage, each with a carrier-gas inlet and outlet as well as a condensing bath and a volume of carrier gas above the condensing bath. The carrier-gas inlet of the second and third stages is in the form of a sieve plate. The first-stage condensing bath is at a temperature of 60° C. to 90° C. Carrier gas flows at a temperature above 60° C. and up to 93° C. into and through the carrier-gas inlet of the first stage, then into and through the condensing bath in the first stage, and then into and through the volume of carrier gas above the condensing bath in the first stage. The carrier gas then similarly flows through the second- and third-stage condensing baths, each of which is at least 5° C. cooler than the temperature of the condensing bath in the preceding stage.

Abstract: Enhanced cleaning of a fouled membrane is achieved via controlled deformation in a method wherein a feed composition, comprising a solvent and dissolved components, flows into a retentate side of a membrane module. The solvent passes through the membrane from the retentate side to a permeate or draw side of the membrane module while retaining the dissolved components on the membrane. As a foulant accumulates on either side of the membrane, a driving force is generated across the membrane, wherein the membrane responds cyclically by deforming back and forth toward the permeate or draw side and toward the retentate side. The foulant is dislodged from the membrane via mechanical fatigue at the foulant-membrane interface caused by the deformation of the membrane and contact with a spacer in contact with the membrane.

Abstract: A first stream of an aqueous solution flows through an upstream desalination or nanofiltration system. A second stream of the aqueous solution is mixed with the diluate output from the upstream desalination system or with the diluate or concentrate output from the upstream nanofiltration system with a flow ratio of the second stream of the aqueous solution to the feed stream of <0.47 or >0.63. A liquid composition flows into the concentrate channels of an electrically driven separation apparatus, while the feed stream flows into at least the diluate channels at a ratio of 0.3 to 0.81 to the flow of the liquid composition. An applied voltage selectively draws monovalent ions from the feed stream in the diluate channels through the monovalent-selective ion exchange membranes into the concentrate channels to produce a treated diluate having a sodium chloride ratio (SCR)<0.7.

Abstract: A feed of at least one of (a) a source liquid including a solvent with a dissolved impurity and (b) a retentate of the source liquid is pumped in a substantially closed loop through a liquid-separation module. The liquid-separation module includes a membrane that passes at least partially purified solvent to a permeate side of the membrane while diverting the impurity in a retentate on the retentate side of the membrane. The purified solvent is extracted from the permeate side of the membrane; and the retentate from the liquid-separation module is pumped to or through a pressurized reservoir with a variable volume for the feed component and recirculated as a component of the feed. Over time, the volume for the feed is reduced and the pressure applied to the feed in the reservoir is increased to balance against an increasing difference in osmotic pressure across the membrane.

Abstract: A bubble-column-humidification apparatus includes a humidifier chamber configured to receive the feed liquid from a feed-liquid source. A bubble distributor is contained in the humidifier chamber; and a humidifier bath of the feed liquid is also contained in the humidifier chamber above the bubble distributor. The feed liquid forms a continuous and majority phase of the humidifier bath and fills a majority of the humidifier chamber, which has a width at least twice as great as its height. A lower gas region is located below the bubble distributor and the humidifier bath in the humidifier chamber and is configured to receive a carrier gas from a carrier-gas source and to disperse the carrier gas through the bubble distributor. The carrier gas in the lower gas region has a pressure greater than the hydrostatic pressure of the humidifier bath.

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 includes at least a first stage and a second stage. Each stage includes a condenser chamber including a carrier-gas inlet and a carrier-gas outlet and contains a condensing bath. Carrier gas bubbles from the carrier-gas inlet up through the condensing bath, overcoming a hydrostatic head of the condensing bath, to a volume of carrier gas above the condensing bath. The carrier-gas outlet is positioned with an opening for carrier-gas extraction, and the first-stage carrier-gas outlet is in fluid communication with the second-stage carrier-gas inlet to facilitate flow of the carrier gas through the condensing bath in the first-stage condenser chamber, into the volume of carrier gas above the first-stage condensing bath, and then through the condensing bath in the second-stage condenser 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: Enhanced cleaning of a fouled membrane is achieved via controlled deformation in a method wherein a feed composition, comprising a solvent and dissolved components, flows into a retentate side of a membrane module. The solvent passes through the membrane from the retentate side to a permeate or draw side of the membrane module while retaining the dissolved components on the membrane. As a foulant accumulates on either side of the membrane, a driving force is generated across the membrane, wherein the membrane responds cyclically by deforming back and forth toward the permeate or draw side and toward the retentate side. The foulant is dislodged from the membrane via mechanical fatigue at the foulant-membrane interface caused by the deformation of the membrane and contact with a spacer in contact with the membrane.

Abstract: Improved reverse osmosis (RO) systems include at least first and second stages wherein each stage has at least one RO membrane, each stage has a feed stream inlet, a permeate stream outlet, and a concentrate stream outlet, the feed stream inlet of the second stage is coupled to the concentrate stream outlet of the first stage, the second pressure is greater than the first pressure, and pressure exchangers associated with each of the first and second stages are configured to recover energy from the second stage concentrate stream. The systems include M reverse osmosis membranes in the first stage and N reverse osmosis membranes in the second stage, wherein M?N. The first pressure and second pressure are configured so that spatial variance in flux of the first stage permeate stream relative to flux of the second stage permeate stream is minimized.

Abstract: A first stream of an aqueous solution flows through an upstream desalination or nanofiltration system. A second stream of the aqueous solution is mixed with the diluate output from the upstream desalination system or with the diluate or concentrate output from the upstream nanofiltration system with a flow ratio of the second stream of the aqueous solution to the feed stream of <0.47 or >0.63. A liquid composition flows into the concentrate channels of an electrically driven separation apparatus, while the feed stream flows into at least the diluate channels at a ratio of 0.3 to 0.81 to the flow of the liquid composition. An applied voltage selectively draws monovalent ions from the feed stream in the diluate channels through the monovalent-selective ion exchange membranes into the concentrate channels to produce a treated diluate having a sodium chloride ratio (SCR) <0.7.

Abstract: Drainage water that includes anions and cations dissolved in water and that is received from an agricultural or industrial facility is treated by applying a voltage to an anode and a cathode on opposite sides of an electrically driven separation apparatus that further includes at least one monovalent-selective ion exchange membrane between the anode and the cathode. The drainage water is passed through the electrically driven separation apparatus, wherein monovalent ions are selected from the drainage water through the monovalent-selective ion exchange membrane. The drainage water is then recirculated as treated water through the facility after the monovalent ions are removed.

Abstract: An aqueous solution flows through a desalination system that separates the aqueous solution into purified water and concentrated brine. The concentrated brine is directed into an electrodialysis system that includes an anode and a cathode and at least two monovalent selective ion exchange membranes between the anode and the cathode. At least one of the monovalent selective ion exchange membranes separates at least one diluate channel from at least one concentrate channel in the electrodialysis system, and this membrane selectively allows at least one monovalent ion to pass through the membrane while blocking or inhibiting the transport therethrough of multi-valent ions. The concentrated brine flows through at least the concentrate channel while a voltage is applied to the anode and cathode; and additional aqueous solution flows through the diluate channel.

Abstract: Improved reverse osmosis (RO) systems include at least first and second stages wherein each stage has at least one RO membrane, each stage has a feed stream inlet, permeate stream outlet, and concentrate stream outlet, the feed stream inlet of the second stage is coupled to the concentrate stream outlet of the first stage, the feed stream entering the first stage is pressurized to a first pressure and the feed stream entering the second stage is pressurized to a second pressure, the second pressure being greater than the first pressure. The systems include M number of reverse osmosis membranes in the first stage and N number of reverse osmosis membranes in the second stage, wherein M?N. The first pressure and second pressure are configured so that flux of the permeate streams of the first stage and the second stage has a spatial variance that is minimized.

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: 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 carrier gas is directed through a humidification chamber in a humidifier, where the carrier gas flow is directly contacted with a feed liquid to humidify the carrier gas with water evaporated from the feed liquid, producing a humidified gas flow. The humidified gas flow is then compressed in a compressor and then directed through a dehumidification chamber in a dehumidifier, where the compressed humidified gas flow is dehumidified to condense water from the compressed humidified gas flow. The dehumidified gas flow is then expanded in an expander, wherein the expansion of the dehumidified gas flow generates motion (e.g., rotation of a shaft), and wherein the motion generated in the expander is transferred to the compressor, where the motion compresses the humidified gas flow. Heat is also removed from the expanded dehumidified gas flow and transferred to compressed dehumidified gas flow upstream from the expander.

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 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.