CROSSFLOW NANOFILTRATION (NF) OF NATURAL NANOPARTICLES AND ORGANIC MATTERS (NOM): FOULING, TRANSPORT AND INTERACTION EFFECTS

摘要

Nanofiltration (NF) is a pressure driven membrane process with applications to the removal of natural organic matter (NOM) and divalent ions in water treatment. Natural waters contain organic and inorganic colloidal particles with sizes between 1 nm and 1μm. In water treatment, these fine colloidal materials may not be effectively removed by coagulation, granular media filters or microfiltration membranes used for pretreatment. Therefore, their potential for causing fouling of subsequent nanofiltration (NF) process is of interest. Most studies focus on the fouling of one component, either NOM alone or colloids alone, and a more limited number have addressed interactions between NOM and colloids during NF. Moreover, due to the complex nature of multiple components, only limited efforts have been made to explain the fouling behaviors of NOM and colloid mixtures mathematically, which is necessary to provide a theoretical basis for, and insight into fouling mechanisms.