Abstract: Disclosed herein is a seawater desalination apparatus using pressure-assisted forward osmosis and reverse osmosis. The seawater desalination apparatus includes: a forward osmosis unit receiving seawater and sewage; and a reverse osmosis unit receiving diluted seawater from the forward osmosis unit, wherein the forward osmosis unit comprises a first train arrangement and a second train arrangement, and the number of trains disposed in the first train arrangement is different from the number of trains disposed in the second train arrangement.

Abstract: An apparatus for effectively filtering and separating fine floc, algae, suspended solids, etc. remaining in water after biological and physiochemical treatment is provided. The fine filtering apparatus includes flexible fibers that control packing density, thus improving filtration efficiency, the amount of clarified water, and filtering duration, and reducing power consumption compared to a conventional filtering apparatus is provided. In the filtering apparatus, flexible fibers having an effective diameter of 1 to 60 ?m and which are flexible, elastic, and have proper surface roughness extend in the longitudinal direction of the apparatus. A jacket shaped unit for supplying source water (supplied water) has a porous structure. Clarified water (treated water) is discharged through a central porous chamber. The whole filter media layer can be utilized as a particle-entrapping space.