Chemical Cleaning of Microfiltration Ceramic Membrane Fouled by Nom

Abstract

Microfiltration membrane made from Sayong ball clay by using uniaxial dry compaction method was used to treat natural organic matter (NOM) source water. A sintering temperature of 900 °C to 1000 °C were applied. The effect of sintering temperature on membrane porosity, strength and water flux were identified. The porosity of the membrane decreased with increasing sintering temperature and the strength and flux increased with temperature. The membrane was subjected to NOM filtration experiments. The results showed an improvement to the quality of permeate water, where there is a reduction in COD, TSS, BOD5, turbidity, hardness and salinity; and an increased pH value. The effect of chemical cleaning on the fouled membrane also was studied. After cleaning with NaOH solution, a high flux recovery was achieved (up to 50% from the initial pure water flux). The degree of cleanliness of fouled membranes after chemical cleaning was further observed with SEM and EDX analysis.

Fouling and Chemical Cleaning of Microfiltration Membranes: A Mini-Review

“…Fouling is the accumulation of particles, macromolecules, biomolecules, salts, and colloids, etc., on the membrane surface or within the pore structure. Recently many studies have focused on mainly oil [24,25], organic algae [26], proteins [27], colloidal material [28], and organic matter foulants [29]. Characterization of the foulants is important to determine whether they accumulate on the surface of the membrane or within the pores.…”

“…Macromolecules of proteins and polysaccharides, minerals, cell debris, protein-polyphenolic aggregates (chill haze), [27,28] Whey Protein, fat, ash, lactose, and moisture. [29,30] Wine clarification Polysaccharides, polyphenols, and tannic acid [43] Skim milk filtration Proteins, minerals, carbohydrates [44] Oil-in-emulsion filtration Oil droplets [45] Cell microfiltration Protein aggregates [46] The foulants interact with the membrane surface both physically and chemically, but chemical interaction between membrane surface and foulants can degrade the membrane material. Hydrophobic interactions, hydrogen bonding, van der Waals attractions, and extracellular macromolecular interactions cause irreversible flux decrease in water treatment applications.…”

“…Temperature impacts have been investigated, and results showed that the permeate flux increased with a low degree of fouling at higher temperatures [29]. Changing the feed temperature between 20 • C and 40 • C means that the penetrating flux rises to 60% [52].…”