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.
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 （ 1100L/（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.
