Application of turbulent pulsating flows to the bacterial removal during a cleaning in place procedure. Part 2 Effects on cleaning efficiency

Walid Blel (1) , Patrick Legentilhomme (1) , Thierry Bénézech (2) , Jack Legrand (1) , Caroline Le Gentil-Lelièvre (2)

1 GEPEA - Laboratoire de génie des procédés - environnement - agroalimentaire
2 PIHM - Processus aux Interfaces et Hygiène des Matériaux

Pulsating turbulent flows effects on cleaning in place procedure of straight pipes were investigated for various pulsations parameters (frequency and amplitude) and mean velocities of the flow. Pulsations generation was made with a new system which allows high amplitude of pulsations. Experiments showed the contribution of the different pulsation parameters, in the removal of adhered bacterial spores, in addition to the effect of the mean velocity of the flow. A high level of the cleaning rate is observed despite the reduction of the magnitude of the mean velocity. This result can be explained by the effect of the two pulsations parameters (amplitude and frequency) which ensure a high wall shear rate. The study of the cleaning kinetics has shown the increase of the removal constant rate of spores using pulsed flow in comparison with the use of a steady turbulent flow.

Mots clés: Pulsating flow; Mass transfer; Food engineering; Fluid mechanics; Process integration; Cleaning in place; Pulsating flow

Domaines: Ingénierie des aliments

Walid Blel, Patrick Legentilhomme, Thierry Bénézech, Jack Legrand, Caroline Le Gentil-Lelièvre. Application of turbulent pulsating flows to the bacterial removal during a cleaning in place procedure. Part 2 Effects on cleaning efficiency. Journal of Food Engineering, 2009, 90 (4), pp.433-440. ⟨10.1016/j.jfoodeng.2008.07.019⟩. ⟨hal-00400256⟩