Beneficial impacts of natural biopolymers during surface water purification by membrane nanofiltration

Membrane filtration in various forms has become an increasingly used treatment method worldwide for the supply of safe drinking water. The fouling membranes is commonly considered to be major operational limitation its wider application since it leads frequent backwashing and a shortening membrane life, increased production costs. components natural organic matter (NOM) surface waters have been reported previously important foulants nanofiltration (NF) membranes, however, potential beneficial effect particular these ‘foulants’ not investigated or demonstrated date. In this study, we roles different materials including autochthonous NOM (e.g., biopolymers) allochthonous humic substances) on NF by bench-scale tests with samples two representative source (UK) taken seasons (autumn winter). Microfiltration (MF) ultrafiltration (UF) were employed generate permeates, between which presence biopolymers (30 kDa – 90 kDa) difference. We developed sequential (MF/UF-NF) investigate biopolymers’ behaviours process. results showed that accumulation can mitigate providing protective layer medium-low molecular weight (MW) (e.g. are separated adsorption and/or size exclusion. layers assisted seen thicker under scanning electron microscope (SEM) observation characterized higher roughness (i.e. three-dimensional, spacial structure) greater adsorptive capacity. Moreover, improvement mitigation could more significant autumn, comparing winter. findings study found repeatable similar comparable raw China, will practical systems terms new approach combating long-term operation.