Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas-liquid systems

determined by using experiments of radioactive particle tracking (RPT)

have been compared. The tracer used is a gel particle which resembles typical immobilized biocatalyst. The tracer trajectory is analyzed to extract relevant information for design purposes. The solid velocity field

turbulence parameters

dispersion coefficients

mixing times and flow transitions are determined and compared. The presence of foam significantly affects many quantified parameters

especially within the heterogeneous flow regime. The hydrodynamic stresses are reduced in the presence of foam

especially close to the disengagement. The dispersion coefficients also decrease

and the solid mixing time is only slightly affected by the presence of foam. Gas holdup

inferred both from RPT experiments and from gamma ray scanning

is higher for foaming systems and leads to a shift in the transition gas velocity towards higher values.