Feed spacer having three-layered structure and reverse osmosis membrane filter module comprising same
Provided is a feed spacer having a three-layered structure, and a reverse osmosis membrane filter module including the same, where the feed spacer includes a first set of a plurality of strands that are positioned in parallel; a second set of a plurality of parallel strands provided to cross the first set; and a third set of a plurality of parallel strands positioned in parallel with a raw water flow direction, where at least one of the first set and the second set consists of strands having a smaller thickness than that of the strands constituting the third set.
1. A feed spacer having a three-layered structure comprising:
a first set of a plurality of strands that are positioned parallel;
a second set of a plurality of parallel strands provided to cross the first set; and
a third set of a plurality of parallel strands positioned in parallel with a raw water flow direction,
wherein one of the first set and the second set consists of strands having a thickness smaller than that of the strands constituting the third set, and
the other set consists of strands having the same thickness as that of the strands constituting the third set,
wherein a ratio of the thickness of the strands constituting the third set and the thickness of the strands having a thickness smaller than the thickness of the strands constituting the third set is 1.1 to 1.5:1.
2. The feed spacer of claim 1 , wherein a strand per inch (SPI) of the feed spacer is 4 to 9.
3. The feed spacer of claim 1 , wherein a distance between intersections of the first set and the second set is 3,800 μm to 12,000 μm.
4. The feed spacer of claim 1 , wherein an angle formed between the first and second sets is 50° to 90°.
5. The feed spacer of claim 1 , wherein the thickness of the feed spacer is 600 μm to 900 μm.
6. A reverse osmosis filter module, comprising the feed spacer having the three-layered structure according to claim 1 .
7. The reverse osmosis filter module of claim 6 , further comprising:
a tube including an opening for accommodating a permeate along a longitudinal direction; and
one or more reverse osmosis membranes configured to extend from the tube in an outer direction and wound around the tube,
wherein the feed spacer is in contact with the one or more reverse osmosis membranes and wound around the tube.