title: Investigation of the effect of viscosity on slug flow in airlift tubular membranes in search of a sludge surrogate.
abstract: The behaviour of three different liquid-gas slug flows (water, carboxymethyl cellulose and activated sludge) in a vertical tube was studied using a high speed camera (HSC). Experiments were performed using different flow rates and two tube diameters (6.3 and 9.9 mm). The observed difference in behaviour of the ascending gas slugs can be explained by the difference in viscosity of the fluids (Newtonian and non-Newtonian). Moreover, it was observed that the degree of coalescence of gas slugs is lower for non-Newtonian liquids and they behave like a succession of slugs without actually coalescing into a single larger gas slug. Finally, gas slug rising velocities were also extracted, but no subsequent difference in the rising velocities of the different fluids was found.
authors.affiliation: Department of Applied Mathematics, Biometrics and Process Control (BIOMATH), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium. nriosrat@biomath.ugent.be
authors.forename: N
authors.initials: N
authors.lastname: Ratkovich
authors.forename: C C V
authors.initials: CC
authors.lastname: Chan
authors.forename: P R
authors.initials: PR
authors.lastname: Bérubé
authors.forename: I
authors.initials: I
authors.lastname: Nopens
mesh_terms: D000392:Air Movements; D019149:Bioreactors; D012722:Sewage; D014783:Viscosity; D014865:Waste Disposal, Fluid
chemical_list: D012722:Sewage