EFFECT OF ADSORPTIVE FOULING ON MEMBRANE PERFORMANCE - CASE-STUDY WITH A PULP-MILL EFFLUENT

The compatibility of a wide range of membrane materials with a pulp mi ll effluent was evaluated with respect to adsorptive fouling. Membrane s were initially evaluated by their pure water permeability and separa tion characteristics with a polyethylene glycol test solute. These mem brane coupons were contacted with a pulp mill effluent sample at 50 de grees C in the absence of a transmembrane pressure for 3 h and then re characterized. The change in the separation and permeation was interpr eted as changes in the average pore size and the ratio of the number o f pores to the effective pore length (n/Delta xA) of the membrane. A d ecreasing pore size indicated the formation of an adsorbed fouling lay er. An increased n/Delta xA ratio suggested that adsorption occurred o n the membrane surface rather than in the pores.