1-13. OIL-WATER
TM 55-2090-201-14&P
SECTION III.
TECHNICAL PRINCIPLES OF OPERATION.
a.
Type C and D Separators.
(1) The design of the C and D oil-water separator is
based on the principle of coalescence.
In this process oily
water is pumped through special filters.
Small droplets of
non-soluble oil mixed in the water attach to the filter surface.
There they combine (coalesce) with other oil droplets.
When the
oil drops become large enough,
fluid flow.
they are forced off of the filter by
Due to the difference in weight (specific gravity),
oil separates from the water and rises to the top.
(2) The system has two vessels. The first is a prefil-
ter.
The second is called a coalescer.
They are connected in
series.
Fluid (influent) containing oil, water and solids is
pumped to the system by a supply pump.
(3) Primary separation and removal of oil from water
takes place in the first stage in the prefilter primary separator.
Inside the vessel is a replacable prefilter element.
Fluid flows
from inside to outside of the element.
It works as follows:
Fluid is pumped through the hollow core of the
filter.
Solids are collected inside the core of the
filter.
Small drops of oil form on the outside of the
filter.
When drops become large enough, they are forced
off the surface by fluid flow.
Oil rises to the top of the vessel.
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