Systems and techniques for electrodialysis
AssigneeEvoqua Water Technologies Pte. Ltd.
InventorsKee Hoe Ng, Rongqiang Fu, Li-Shiang Liang, Zhee Min Jimmy Yong, Keng Hoo Yeo
Life of this patent
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Abstract
Electrochemical separation devices are configured for lower energy consumption. Techniques for reducing shadow effect may involve providing distance between a spacer screen and an adjacent ion-selective membrane. A spacer having a screen that is thin relative to a surrounding frame may be used. Mild pressure may also be applied to a compartment to promote distance between a spacer screen and an adjacent ion-selective membrane.
Claims19
An electrodialysis device, comprising:
- a first compartment positioned between a pair of electrodes, the first compartment at least partially defined by a first ion selective membrane and a second ion selective membrane, the first compartment containing no electroactive media and having a flow channel width of greater than 3 cm;
- and
- a spacer comprising a mesh screen surrounded by a frame that is thicker than the mesh screen, the spacer positioned between the first and second ion selective membranes and constructed and arranged to maintain separation between the mesh screen and each of the first and second ion selective membranes.
A method of treating water, comprising:
- introducing the water to a diluting compartment of an electrodialysis device comprising a pair of electrodes;
- pressurizing the diluting compartment to promote separation of a spacer mesh screen from an adjacent ion selective membrane in the diluting compartment of the electrodialysis device;
- promoting transport of an ionic species in the water from the diluting compartment to a concentrating compartment of the electrodialysis device, each of the diluting compartment and the concentrating compartment containing no electroactive media;
- and
- recovering treated water at an outlet of the diluting compartment.
A method of facilitating the reduction of energy consumption in an electrodialysis device by at least 10%, the method comprising:
- providing an electrodialysis device comprising at least one compartment partially defined by a first ion selective membrane and a second ion selective membrane, the at least one compartment containing no electroactive media and having a flow channel width of greater than 3 cm;
- and
- providing a spacer comprising a mesh screen surrounded by a frame that is thicker than the mesh screen between the first and second ion selective membranes, the spacer constructed and arranged to maintain separation between the mesh screen and each of the first and second ion selective membranes.
Dependencies are inferred from the claim text.