Preparation of polyethylene porous tube membrane and fouling mechanism during the filtration process

Polyethylene porous filter tube membranes were prepared by powder sintering method. The micro-structure of the tubular membrane, the effect of inorganic particles, and emulsified oil on membrane fouling were studied. The membrane flux variation curves were analyzed to further reveal the fluxing mechanisms. The results showed the membrane was composed of particles with the size of 10–60 μm, and there were many irregularly shaped three-dimensional through pores with the size of 20–70 μm in its cross-section. For inorganic particle dispersion filtration, the larger the dispersion concentration was, the greater the membrane flux dropped, and the smaller the irreversible fouling was; the smaller the inorganic particle size and the higher the filtration flow rate were, the greater the membrane flux dropped and the greater the irreversible fouling were; The analysis showed that at the beginning of filtration, the membrane first underwent complete pore blocking, and as the filtration process proceeds, the contamination pattern of the membrane changed, and cake filtration blocking occurred. For emulsified oil filtration, the larger the pH value was, the smaller the zeta potential, and the smaller the emulsified oil was, the greater the decreased in membrane flux and the greater the irreversible fouling was. For the filtration of turbid ring water with inorganic particles and emulsified oil, the membrane flux decreased less than the filtration with emulsified oil only; as the concentration of emulsified oil increased, the irreversible fouling tended to rise.