Patent ID: 9079789
Filing Date: 2015-07-14
Classification: C02F

Abstract:
1. A water treatment apparatus, which is arranged for capacitive deionization of a liquid, wherein: the apparatus includes electrodes, each electrode being: (a) a thin sheet of a porous, high-surface-area, material; (b) permeable to water flowing thickness-wise through the thickness of the electrode; the apparatus includes spacers, each spacer being: (a) electrically insulative; (b) permeable to water flowing thickness-wise through the thickness of the spacer; the spacers lie intercalated between adjacent electrodes, to form a stack of electrodes and spacers; the apparatus also includes: (a) a power unit for supplying electrical energy to the electrodes; (b) a treatment-inlet-port, through which water to be treated enters the apparatus; (c) a treatment-outlet-port, through which treated water exits the apparatus; (d) a purge-inlet-port, through which purge-water enters the apparatus; (e) a purge-outlet-port, through which purge-water exits the apparatus; (f) waterways for conveying treatment-water from the treatment-inlet-port, through the stack, to the treatment-outlet-port; (g) waterways for conveying purge-water from the purge-inlet-port, through the stack, to the purge-outlet-port; the apparatus is so structured and arranged as to be operable in a treatment-phase and in a regeneration-phase, and is switchable between the two phases; in the treatment-phase, the power unit is so configured that: (a) the power unit supplies electricity to the electrodes in such manner as to create pairs of anodes and cathodes; (b) the capacitive deionization function arises, in that ions are electrostatically attracted out of the treatment-water and are sorbed into the pores of the electrodes; in the treatment-phase, the waterways are so configured that: (a) there is no liquid-flow-communication through the stack, between the purge-inlet-port and the purge-outlet-port; (b) there is no liquid-flow-communication between adjacent spacers, other than thickness-wise through the thickness of the intervening electrode; (c) treatment-water enters the apparatus through the treatment-inlet-port; (d) the treatment-water passes through the stack thickness-wise through the thicknesses of the electrodes and spacers; (e) the treatment-water passes through the stack, spacer-anode-spacer-cathode-spacer-anode-spacer-cathode-spacer, and so on, thickness-wise through the thicknesses of the electrodes and thickness-wise through the thicknesses of the intercalated spacers, in series, through the stack; (f) the treatment-water exits through the treatment-outlet-port; in the purge-phase, the power-unit is so configured that: the sorbed ions are no longer electrostatically attracted to the electrodes; in the purge-phase, the waterways are so configured that: (a) there is no liquid-flow-communication, through the stack, between the treatment-inlet-port and the treatment-outlet-port; (b) north-edges of the spacers are in liquid-flow-communication with the purge-inlet-port; (c) south-edges of the spacers are in liquid-flow-communication with the purge-outlet-port; (d) whereby the purge-water passes through the spacers of the stack, in the direction parallel to the planes of the spacers, from the purge-inlet-port to the purge-outlet-port.