Feed spacer having three-layered structure, and reverse osmosis membrane filter module including same
Provided is a feed spacer having a three-layer structure, in which a set forming the feed spacer is formed in a three-layer structure, so that the set, which is in contact with a reverse osmosis membrane, convects raw water to a center of the structure of the feed spacer and a laminar flow velocity gradient is generated at the center to decrease a polarization phenomenon of a reverse osmosis filter module and minimize pressure loss, and a reverse osmosis membrane filter module including the feed spacer.
1. A feed spacer having a three-layer structure, comprising:
a first set, in which a plurality of strands is positioned in parallel;
a second set, which crosses the first set forming cross points, and is formed of a plurality of parallel strands; and
a third set, which is positioned in parallel to a flow direction of raw water and is formed of a plurality of parallel strands,
wherein the third set is positioned between the first and second sets,
wherein a gap between the strands forming the first set, second set, and third set is from 11 to 12 mm,
wherein a length between cross points of the first and second sets is 10,720 μm to 12,000 μm,
wherein an angle between the strands of the first set and strands of the second set is 50° to 55°; and
wherein the feed spacer has a thickness of 500 μm to 900 μm.
2. The feed spacer of claim 1 , wherein a diameter of the strands forming each of the first set, the second set, and the third set is 167 μm to 300 μm.
3. A reverse osmosis filter module, comprising the feed spacer of claim 1 .
4. The reverse osmosis filter module of claim 3 , wherein the reverse osmosis filter module includes:
a tube including an opening accommodating a permeating liquid in a longitudinal direction; and
one or more reverse osmosis membranes, which are extended from the tube in an outside direction and are wound around a circumference of the tube, and
the spacer is in contact with the one or more reverse osmosis membranes and is wound around the circumference of the tube.
5. The reverse osmosis filter module of claim 4 , wherein the spacer is formed of the first to third sets, and the first and second sets are in contact with the one or more reverse osmosis membranes, and the third set is not in contact with the one or more reverse osmosis membranes.