Coarse mineral particle slurry with particle sizes of over
100 mm can sometimes be pumped cost effectively with
centrifugal pumps in dredging and mining operations. For
example, phosphate matrix is recovered in open pit opera-
tions, slurry and pumped in large pipelines of up to 20 km
in Florida. The flow of industrial slurry can generally be
illustrated as consisting of a homogeneous fluid medium
formed by water and the finer particles of less size than about
0.05 mm. The coarser particles then act stratified or hetero-
geneously in this suspension. Maciejewski et al. [2] com-
pared large diameter transportation of coarse particles of
about 100 mm in clay suspensions and tar sand railings slur-
ry and found that the sand slurry was more effective as a
transport medium than a viscous, homogeneous clay slurry.
This result is of great practical interest, because energy-effi-
cient pipeline transportation of coarse particles can then be
combined with rather simple separation techniques at the
discharge end. The results by Maciejewski et al