Regenerable filter unit, regenerable filter system including the same, and method of operating regenerable filter system

A filter system comprising:

• a filter unit including an electrode structure, a fluid-purifying flow path, a pH adjusting chamber, at least one sub-electrode structure, and a adsorbent in the fluid-purifying flow path and not in the pH adjusting chamber;
• the electrode structure including a cathode, a cation exchange membrane, an anion exchange membrane, and an anode, the cation exchange membrane disposed between the cathode and the anion exchange membrane, the anion exchange membrane disposed between the cation exchange membrane and the anode;
• the fluid-purifying flow path being at least one of a path defined by an inner surface of the cathode, a path defined by the cathode and the cation exchange membrane, a path between the anion exchange membrane and the anode, and a path defined by the anode, the pH adjusting chamber defined by the cation exchange membrane and the anion exchange membrane, the pH adjusting chamber configured to control a pH of a fluid in the fluid-purifying flow path;
• the at least one sub-electrode structure disposed between the cation exchange membrane and the anion exchange membrane, the sub-electrode structure including a sub-anion exchange membrane, a bipolar membrane, and a sub-cation exchange membrane defining at least one sub-fluid-purifying flow path therebetween, the bipolar membrane being between the sub-anion exchange embrane and the sub-cation exchange membrane;
• and
• a voltage applier configured to apply a voltage to the cathode and the anode.

A method of driving a filter system, the method comprising:

• purifying a fluid by passing an inflow through a fluid-purifying flow path of a filter unit of the filter system, the filter unit including an electrode structure, the fluid-purifying flow path, and a pH adjusting chamber, at least one sub-electrode structure, and an adsorbent in the fluid-purifying flow path and not in the pH adjusting chamber, the electrode structure including a cathode, a cation exchange membrane, an anion exchange membrane and an anode, the cation exchange membrane disposed between the cathode and the anion exchange membrane, te anion exchange membrane disposed between the cation exchange membrane and the anode, the fluid-purifying flow path being at least one of a path defined by an inner surface of the cathode, a path defined by the cathode and the cation exchange membrane, a path defined by the anion exchange membrane and the anode, and a path defined by the anode, the pH adjusting chamber defined by the cation exchange membrane and the anion exchange membrane, the pH adjusting chamber configured to control a pH of the fluid in the fluid-purifying flow path, the at least one sub-electrode structure disposed between the cation exchange membrane and the anion exchange membrane, the sub-electrode structure including a sub-anion exchange membrane, a bipolar membrane, and a sub-cation exchange membrane defining at least one sub-fluid-purifying flow path therebetween, the bipolar membrane being between the sub-anion exchange membrane and the sub-cation exchange membrane;and
• regenerating the fluid-purifying flow path by applying a voltage to the cathode and the anode while supplying water through the electrode structure.