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: 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: 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 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 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 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 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: 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 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 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 humidification-dehumidification apparatus featuring enhanced heat recovery includes a shared interior wall extending along a vertical axis and defining and separating humidifying and dehumidifying chambers. Heat-transfer members extend through the shared interior wall and across a majority of each chamber, while a spray device is configured to direct a spray of liquid feed composition onto the heat-transfer members inside the humidifying chamber. The liquid feed collects on the heat-transfer members in the humidifying chamber, and water evaporates from the liquid feed on the heat-transfer members, leaving a concentrated remainder of the liquid feed in liquid form. Carrier gas passes through the humidifying chamber where evaporated water is entrained in the carrier gas to form a moist carrier gas that passes from the humidifying chamber to the dehumidifying chamber, where the water vapor condenses from the moist carrier gas on the heat-transfer members.