Abstract: Self-cleaning electrochemical cells, systems including self-cleaning electrochemical cells, and methods of operating self-cleaning electrochemical cells are disclosed. The self-cleaning electrochemical cell can include a plurality of concentric electrodes disposed in a housing, a fluid channel defined between the concentric electrodes, and an electrical connector positioned at a distal end of a concentric electrode and electrically connected to the electrode. The electrical connectors may be configured to provide a substantially even current distribution to the concentric electrode and minimize a zone of reduced velocity occurring downstream from the electrical connector. The electrical connector may be configured to cause a temperature of an electrolyte solution to increase by less than about 0.5° C. while transmitting at least 100 W of power.

Abstract: An electrochemical separation device includes a first electrode, a second electrode, and a cell stack including a plurality of sub-blocks each having alternating depleting compartments and concentrating compartments and each including frame and channel portions disposed between the first electrode and the second electrode. An internal seal formed of a first material is disposed between and in contact with the channel portions between adjacent sub-blocks in the cell stack and configured to prevent leakage between depleting compartments and concentrating compartments in the adjacent sub-blocks. An external seal formed of a second material having at least one material parameter different from the first material is disposed between and in contact with the frames of the adjacent sub-blocks in the cell stack and configured to prevent leakage from an internal volume of the electrochemical separation device to outside of the electrochemical separation device.

Abstract: Self-cleaning electrochemical cells, systems including self-cleaning electrochemical cells, and methods of operating self-cleaning electrochemical cells are disclosed. The self-cleaning electrochemical cell can include a plurality of concentric electrodes disposed in a housing, for example, a cathode and an anode, a fluid channel defined between the concentric electrodes, a separator residing between the concentric electrodes, first and second end caps coupled to respective ends of the housing, and an inlet cone. The separators may be configured to localize the electrodes and dimensioned to minimize a zone of reduced velocity occurring downstream from the separator. The end caps and inlet cone may be dimensioned to maintain fully developed flow and minimize pressure drop across the electrochemical cell.

Abstract: Water filtration systems are disclosed. The water filtration systems include a regenerative media filter vessel comprising a housing, an inlet, and an outlet, a diffuser fluidly connected to the inlet and disposed within the regenerative media filter vessel, and at least one pump configured to direct water through the water filtration system. The housing of the regenerative media filter vessel comprises a concave lower portion centered about a vertical axis of the vessel. The position of the diffuser along a height of the regenerative media filter vessel is determined by at least a ratio of the height to an inner diameter of the regenerative media filter vessel and a radius of curvature of the concave lower portion. A regenerative media filter including a diffuser having asymmetrically spaced apertures is also disclosed.

Abstract: Self-cleaning electrochemical cells, systems including self-cleaning electrochemical cells, and methods of operating self-cleaning electrochemical cells are disclosed. The self-cleaning electrochemical cell can include a plurality of concentric electrodes disposed in a housing, for example, a cathode and an anode, a fluid channel defined between the concentric electrodes, a separator residing between the concentric electrodes, first and second end caps coupled to respective ends of the housing, and an inlet cone. The separators may be configured to localize the electrodes and dimensioned to minimize a zone of reduced velocity occurring downstream from the separator. The end caps and inlet cone may be dimensioned to maintain fully developed flow and minimize pressure drop across the electrochemical cell.

Abstract: An electrochemical separation device includes a first electrode, a second electrode, a cell stack including alternating depleting compartments and concentrating compartments disposed between the first electrode and the second electrode, an inlet manifold configured to introduce a fluid to one of the depleting compartments or the concentrating compartments an outlet manifold, and one or more of a fluid flow director disposed within the inlet manifold and having a surface configured to alter a flow path of the fluid introduced into the inlet manifold and direct the fluid into the one of the depleting compartments or the concentrating compartments, and a second fluid flow director disposed within the outlet manifold and having a surface configured to alter a flow path of the fluid introduced into the outlet manifold via one of the depleting compartments or the concentrating compartments.

Abstract: An electrochemical separation device includes a first electrode, a second electrode, and a cell stack including a plurality of sub-blocks each having alternating depleting compartments and concentrating compartments and each including frame and channel portions disposed between the first electrode and the second electrode. An internal seal formed of a first material is disposed between and in contact with the channel portions between adjacent sub-blocks in the cell stack and configured to prevent leakage between depleting compartments and concentrating compartments in the adjacent sub-blocks. An external seal formed of a second material having at least one material parameter different from the first material is disposed between and in contact with the frames of the adjacent sub-blocks in the cell stack and configured to prevent leakage from an internal volume of the electrochemical separation device to outside of the electrochemical separation device.

Abstract: A method of providing water suitable for irrigation use includes feeding pre-treated water to an electrodialysis apparatus, treating the pre-treated water in the electrodialysis apparatus by selectively removing either one or both of monovalent anionic and monovalent cationic species from the pre-treated water while retaining either one or both of multivalent anionic and multivalent cationic species to produce a treated water stream having a lower ratio of monovalent ions to multivalent ions than the pre-treated water, and directing the treated water into an irrigation water distribution system.

Abstract: Self-cleaning electrochemical cells, systems including self-cleaning electrochemical cells, and methods of operating self-cleaning electrochemical cells are disclosed. The self-cleaning electrochemical cell can include a plurality of concentric electrodes disposed in a housing, a fluid channel defined between the concentric electrodes, and an electrical connector positioned at a distal end of a concentric electrode and electrically connected to the electrode. The electrical connectors may be configured to provide a substantially even current distribution to the concentric electrode and minimize a zone of reduced velocity occurring downstream from the electrical connector. The electrical connector may be configured to cause a temperature of an electrolyte solution to increase by less than about 0.5° C. while transmitting at least 100 W of power.

Abstract: An electrochemical separation device includes a first electrode, a second electrode, a cell stack including alternating depleting compartments and concentrating compartments disposed between the first electrode and the second electrode, an inlet manifold configured to introduce a fluid to one of the depleting compartments or the concentrating compartments an outlet manifold, and one or more of a fluid flow director disposed within the inlet manifold and having a surface configured to alter a flow path of the fluid introduced into the inlet manifold and direct the fluid into the one of the depleting compartments or the concentrating compartments, and a second fluid flow director disposed within the outlet manifold and having a surface configured to alter a flow path of the fluid introduced into the outlet manifold via one of the depleting compartments or the concentrating compartments.

Abstract: A method of operating an electrochemical device includes periodically discharging a volume of concentrate reject in a timed batch cycle and replacing the concentrate reject with feed water. An electrochemical water treatment system includes a recycle line having a valve controlled by a control module. The control module periodically opens the valve to discharge concentrate reject from the recycle line in a batch timed cycle. The recycle line is fed with feed water to replace the discharged concentrate reject.

Abstract: An electrochemical cell includes a housing having an inlet, an outlet, and a central axis and an anode-cathode pair disposed concentrically within the housing about the central axis and defining an active area between an anode and a cathode of the anode-cathode pair. An active surface area of at least one of the anode and the cathode has a surface area greater than a surface area of an internal surface of the housing. The anode-cathode pair is configured and arranged to direct all fluid passing through the electrochemical cell axially through the active area.

Abstract: A module comprises a cell stack having a plurality of alternating ion depleting compartments and ion concentrating compartments, an inlet manifold configured to facilitate a flow of fluid into the cell stack, and a first flow distribution system, associated with the inlet manifold, including a first ramp to promote the circulation of the flow of fluid into the cell stack.

Abstract: A method of operating an electrochemical device includes periodically discharging a volume of concentrate reject in a timed batch cycle and replacing the concentrate reject with feed water. An electrochemical water treatment system includes a recycle line having a valve controlled by a control module. The control module periodically opens the valve to discharge concentrate reject from the recycle line in a batch timed cycle. The recycle line is fed with feed water to replace the discharged concentrate reject.

Abstract: A water treatment system for brackish water is disclosed. The water treatment system includes a first electrochemical separation stage fluidly connected to a second, downstream electrochemical separation stage, with the concentrate outlet of the second electrochemical separation stage fluidly connectable to the concentration compartment of the first electrochemical separation stage and a control system configured to regulate feed directed to the concentration compartments of the first and the second electrochemical separation stages. Methods of treating brackish water to produce potable water and methods of treating brackish water using systems of the invention are disclosed. The Donnan potential difference and osmotic water losses are lessened by controlling a source and a flowrate of a make-up feed water directed to concentration compartments of first and the second electrochemical separation stages of the systems.

Abstract: Methods of operating an electrochemical separation device is disclosed. The methods include operating the electrochemical separation device in an active mode until the resistance reaches a predetermined threshold, regenerating the electrochemical separation device in a passive mode until the resistance reaches a predetermined threshold, and resuming operation of the electrochemical separation device in the active mode. The methods also include operating the electrochemical separation device in an active mode for a predetermined period of time, regenerating the electrochemical separation device in a passive mode for a predetermined period of time, and resuming operation of the electrochemical separation device in the active mode. Water treatment systems include the electrochemical separation device and a control module are also disclosed. Methods of facilitating operation of the electrochemical separation device by providing a control sequence are also disclosed.

Abstract: Self-cleaning electrochemical cells, systems including self-cleaning electrochemical cells, and methods of operating self-cleaning electrochemical cells are disclosed. The self-cleaning electrochemical cell can include a plurality of concentric electrodes disposed in a housing, for example, a cathode and an anode, a fluid channel defined between the concentric electrodes, a separator residing between the concentric electrodes, first and second end caps coupled to respective ends of the housing, and an inlet cone. The separators may be configured to localize the electrodes and dimensioned to minimize a zone of reduced velocity occurring downstream from the separator. The end caps and inlet cone may be dimensioned to maintain fully developed flow and minimize pressure drop across the electrochemical cell.

Abstract: Self-cleaning electrochemical cells, systems including self-cleaning electrochemical cells, and methods of operating self-cleaning electrochemical cells are disclosed. The self-cleaning electrochemical cell can include a plurality of concentric electrodes disposed in a housing, a fluid channel defined between the concentric electrodes, and an electrical connector positioned at a distal end of a concentric electrode and electrically connected to the electrode. The electrical connectors may be configured to provide a substantially even current distribution to the concentric electrode and minimize a zone of reduced velocity occurring downstream from the electrical connector. The electrical connector may be configured to cause a temperature of an electrolyte solution to increase by less than about 0.5° C. while transmitting at least 100 W of power.

Abstract: An electrochlorination system includes an electrolyzer fluidically connectable between a source of feed fluid and a product fluid outlet, and a sub-system configured to one of increase a pH of the feed fluid, or increase a ratio of monovalent to divalent ions in the feed fluid, upstream of the electrolyzer.