Study of membrane cleaning with and without ultrasounds application after fouling with three model dairy solutions

Abstract

The aim of this study was to investigate the behavior of two ultrafiltration (UF) membranes after their fouling with different fouling solutions and cleaning with a surfactant, including the application of ultrasounds (US). Thus,two UF membranes (UH030 and UP005) were fouled with three different whey model solutions that consisted of bovine serum albumin (BSA) with a concentration of 1% (w/w), BSA (1%, w/w) plus CaCl2 with a concentration of 0.17% (w/w) and whey solution (Renylat 45) with a concentration of 2.22% (w/w). Chemical cleaning was carried out with P3 Ultrasil 115 solution at temperatures between 25 ◦C and 45 ◦C and concentrations in the range between 0.5% (v/v) and 0.9% (v/v). US were applied in some ofthe tests at a frequency of 20 kHz and nominal power of 300W. The results demonstrated that US cleaning was effective to enhance the permeability recovery, although this enhancement was only up to 9%. Concerning fouling, results from resistances calculations showed that for UH030 membrane prevails the reversible fouling whereas for UP005 membrane predominate irreversible fouling