TY - JOUR
T1 - Analytical and Numerical Modelling of Newtonian and non-Newtonian Liquid in a Rotational Cross-flow MBR
AU - Bentzen, Thomas Ruby
AU - Ratkovich, Nicolas Rios
AU - Madsen, S.
AU - Jensen, J. C.
AU - Bak, S. N.
AU - Rasmussen, Michael R.
PY - 2012
Y1 - 2012
N2 - Fouling is the main bottleneck of the widespread use of MBR systems. One way to decrease and/or control fouling is by process hydrodynamics. This can be achieved by the increase of liquid cross- flow velocity. In rotational cross-flow MBR systems, this is attained by the spinning of, for example, impellers. Validation of the CFD (computational fluid dynamics) model was made against laser Doppler anemometry (LDA) tangential velocity measurements (error less than 8%) using water as a fluid. The shear stress over the membrane surface was inferred from the CFD simulations for water. However, activated sludge (AS) is a non-Newtonian liquid, for which the CFD model was modified incorporating the non-Newtonian behaviour of AS. Shear stress and area-weighted average shear stress relationships were made giving error less that 8% compared with the CFD results. An empirical relationship for the area-weighted average shear stress was developed for water and AS as a function of the angular velocity and the total suspended solids concentration. These relationships can be linked to the energy consumption of this type of systems.
AB - Fouling is the main bottleneck of the widespread use of MBR systems. One way to decrease and/or control fouling is by process hydrodynamics. This can be achieved by the increase of liquid cross- flow velocity. In rotational cross-flow MBR systems, this is attained by the spinning of, for example, impellers. Validation of the CFD (computational fluid dynamics) model was made against laser Doppler anemometry (LDA) tangential velocity measurements (error less than 8%) using water as a fluid. The shear stress over the membrane surface was inferred from the CFD simulations for water. However, activated sludge (AS) is a non-Newtonian liquid, for which the CFD model was modified incorporating the non-Newtonian behaviour of AS. Shear stress and area-weighted average shear stress relationships were made giving error less that 8% compared with the CFD results. An empirical relationship for the area-weighted average shear stress was developed for water and AS as a function of the angular velocity and the total suspended solids concentration. These relationships can be linked to the energy consumption of this type of systems.
KW - CFD
KW - Non-Newtonian
KW - Rotating Cross-Flow MBR
KW - Shear Stress
KW - CFD
KW - Non-Newtonian
KW - Rotating Cross-Flow MBR
KW - Shear Stress
UR - http://www.scopus.com/inward/record.url?scp=84872730590&partnerID=8YFLogxK
U2 - 10.2166/wst.2012.443
DO - 10.2166/wst.2012.443
M3 - Journal article
SN - 0273-1223
VL - 66
SP - 2318
EP - 2327
JO - Water Science and Technology
JF - Water Science and Technology
IS - 11
ER -