DESCRIPTION OF 3-PHASE FILTRATION WITH A NOVEL DIMENSIONLESS NUMBER

Internal filtration in slurry bubble columns offers a possible solutio n to the filtration problems related to this reactor type. The applica bility of the concept has already been demonstrated at full-scale for wastewater treatment, even though a theoretical description of interna l filtration is lacking. Two types of hydrodynamic models were develop ed for a filtering slurry reactor. Both the model of the surface renew al type and the model based on a force-balance approach predict that t he solids concentration at the axial position of the filter uniquely d epends on a single novel dimensionless number. The validity of these t heories was demonstrated by measuring filter-cake resistance as an ind irect measure of solids concentration for a system in batch operation with respect to solids. In the experiments the load of solids, permeat e flux (J), superficial gas velocity (U-g), particle diameter (d(p)), kinematic liquid viscosity (v(l)), and molar mass of the gas were vari ed.