Capacitive deionization electrode module and water treatment apparatus and method capable of saving energy using the same

A capacitive deionization electrode module comprising:

• a housing having a circular cylindrical shape and a center axis, the housing including a circular face disposed at each end of the housing and an end face hole formed at the center of each circular face;
• a pair of circular electrodes disposed inside the housing, each of the pair of circular electrodes having a diameter of 30 to 40 cm and a first hole formed at the center of a corresponding circular electrode of the pair of circular electrodes;
• and
• a plurality of circular intermediate electrodes disposed inside the housing and spaced apart from each other and from each of the pair of circular electrodes, each of the plurality of circular intermediate electrodes having a diameter of 30 to 40 cm and a second hole formed at the center of a corresponding circular intermediate electrode of the plurality of circular intermediate electrodes,
• wherein the end face holes, the first holes, and the second holes are arranged linearly along the center axis of the housing and communicate with each other to form a linear flow passage through the housing, the pair of circular electrodes, and the plurality of circular intermediate electrodes,
• wherein each of the end face holes, the first holes, and the second holes has a center aligned with the center axis of the housing and includes an inner circumferential surface that is concentric with the center axis of the housing and forms a part of the linear flow passage, the respective inner circumferential surfaces being formed an equal distance from the center axis of the housing such that the end face holes, the first holes, and the second holes have equal diameters and such that the inner circumferential surfaces of the respective parts of the linear flow passage are aligned with each other in an axial direction of the housing,
• wherein the housing is configured to pass incoming water along the linear flow passage formed by the end face holes, the first holes, and the second holes,
• wherein the linear flow passage is mixedly filled with cation exchange resins and anion exchange resins to reduce an electrical resistance through the linear flow passage,
• wherein the plurality of circular intermediate electrodes are arranged in a housing space defined by the pair of circular electrodes and are spaced apart within the housing space to form a plurality of gaps respectively interposed between adjacent pairs of the plurality of circular intermediate electrodes, each of the plurality of gaps forming a plenum having a given axial distance and enabling formation of an expanded flow path between the respective electrodes of the plurality of circular intermediate electrodes, and
• wherein each plenum formed by the plurality of gaps includes
• a radially inner portion that extends radially from the center axis to the inner diameter of the linear flow passage and
• a radially outer portion, as the expanded flow path, that extends radially from the inner diameter of the linear flow passage to the inner diameter of the housing.