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Special

applications

8.1 Slurry pumping

Slurry is a mixture of solid particles suspended in a liquid that is usually
water. The variety of solids that are handled in slurry form covers an
extraordinary wide range of products and waste material.
One of the key elements in slurry pumping is the size and nature of the
solids being transported by the water and the nature of the abrasive
wear it causes. As wear is a function of velocity, the pumps usually
operate at 1200 rpm or slower.
The centrifugal pumps used in slurry handling are basically
conventional water pumps modified in a variety of ways to handle the
particular solids. While some of these modifications are minimal, some
of them are quite extensive. The difference depends on the size and
nature of the solids being handled.
Although the emphasis on a slurry pump tends to be on the size and
percentage of solids to be moved, it should be remembered that many
of these slurry applications are in services where corrosion resistance is
also a factor. In such cases, material selection for corrosion resistance
needs to be combined with the pump style selection.

9 1.1 Industrial slurries
In general industry where water run-off in the plant may drain to a
central sump and is then pumped out to a collection tank, the solids in
the water usually represent plant debris and tend to be quite small. As
they also represent a low percentage of the total volume, the slurry can
usually be handled by a conventional centrifugal sump pump. The
specific pump design in these services can be quite varied, but the
traditional vertical submerged suction sump pump and the submersible
pump are both widely used.

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