The role of the nature and composition of solutions/suspensions in fouling of plane organic membranes in frontal filtration: Application to water and wastewater clarification

The aim of this study was to evaluate and quantify the filterability of various defined solutions/suspensions according to their nature and their composition. A laboratory-scale filtration unit with plane organic membranes was used. The fouling potential of different compounds, like bentonite, ferric hydroxide, powdered activated carbon (PAC), latex, humic acid, protein, bacterial compounds, was studied and the filterability of the solutions/suspensions was examined with and without conditioning by ferric chloride and powdered activated carbon addition. Experimental results showed very clearly that the resistance coefficients of mineral suspensions were lower than the ones of organic suspensions in the same conditions of concentration. Suspension conditioning or adsorption, adding ferric chloride or CAP, allowed reducing the membrane fouling due to the soluble and colloidal fractions retention in the particular elements. For bacterial suspensions, adsorption phenomena and particular deposit could explain the fouling observed.