Operation Characteristics of Treating Surface Water with Polyvinylchloride Hollow Fiber Ultrafiltration Membrane

摘要

A pilot plant study on a polyvinylchloride hollow fiber ultrafiltration membrane process was conducted for treating surface water. The membrane system was operated in the dead-end filtration mode under different constant permeate fluxes. The results show that the optimized operation (transmembrane pressure ≤ 0.1 MPa, filtration time ≤ 30 min) with a hydraulic cleaning (30 s) and a chemical cleaning (30 min, the chemical cleaning was performed after 16 cycles of filtration ) ensures a quite steady flux (1 100 L/(m~2 • h • MPa)) and good permeate quality (turbidity < 0. 1 NTU). A full-scale plant can be suggested to operate with a mixed strategy of constant permeate flux mode (transmembrane pressure ≤ 0.1 MPa) and constant transmembrane pressure mode. When the temperature of raw water becomes below 5 ℃, a constant transmembrane pressure mode should be used; otherwise a constant permeate flux mode (transmembrane pressure ≤ 0.1 MPa) can be operated. In this way, irreversible fouling of ultrafiltration membrane can be minimized to keep a stable flux and make the life of membrane longer.