Patent ID: 8915378
Filing Date: 2014-12-23
Classification: B01D,C02F,Y02A

Abstract:
1. A hollow fiber type reverse osmosis membrane for low pressure use at an operation pressure of 2.0 MPa or lower comprising cellulose acetate, characterized in that the filtration rate and the salt rejection rate when an aqueous solution having sodium chloride concentration of 1,500 mg/L is filtered from outer side to inner side of the hollow fiber type reverse osmosis membrane at 25° C. and 1.5 MPa pressure are 180 to 350 L/m 2 /day and 90.0 to 99.0%, respectively and the outer diameter, the inner diameter and the hollow rate of the hollow fiber type reverse osmosis membrane are 100 to 280 μm, 50 to 200 μm and 24 to 42%, respectively; wherein a dense layer in 0.1 to 7 μm thickness exists near the outer surface of the hollow fiber type reverse osmosis membrane.