Radioisotope tracers have a proven application for the extraction of r
esidence time distributions and the evaluation of flotation rates in i
ndustry. This paper shows how values of the rate factor k are scaled u
p on the basis of flotations in the laboratory and tracer tests in pla
nt. The procedure is illustrated by a theoretical study and by experim
ental data. The information obtained can be introduced into models of
larger flotation systems.