Effects of micro-/nanobubble on membrane antifouling performance and the mechanism insights

Membrane fouling problem has become a painful point of the membrane industry by causing huge energy consumption, material wastage and high cost. Micro-/nanobubbles (MNBs) as a novel strategy can effectively inhibit adhesion of pollutants during the treatment processes. The introduction of MNBs technology into membrane separation systems can be a worthy research topic for membrane antifouling. In the current study, it was found that the MNBs displayed significant effects on membrane permeability, rejection performance and especially antifouling performance. The experimental results confirmed that the MNBs effectively improved the permeability of membranes during the filtration processes. The separation tests showed that the MNBs can delay the flux attenuation and promote antifouling ability of 165.9%. Nanoparticle tracking analysis (NTA) results indicated that the pollutants tended to larger size particles which can be attributed to the agglomeration effect of MNBs. The MNBs served as a “gas bridge” between pollutants and membrane surface therefore can efficiently prevent the adhesions of pollutants. The MNBs technology with “gas bridge” effects can provides a novel strategy for membrane fouling control.