The Removal of Fatty Acids and
Soaps from Soap-Manufacturing
Waste Waters
F. S. Gibbs
F. S. Gibbs, Inc.
Boston, Massachusetts
Getting involved in industrial waste-water treatment problems is
not conducive to peace of mind and fireside contentment. It spoils
your clothes, rots your shoes, smears your face, blackens your finger¬
nails, perfumes your hair, cools your meals, ruins your sleep, and makes
your wife wonder why she ever was foolish enough to marry an
engineer.
One excellent way to get involved is to visit or work in treatment
plants when they are experiencing operating difficulties and then try
to dream up better means for overcoming these difficulties.
One of the most frequent difficulties is the inability to effect con¬
tinuous efficient clarification and to produce workable sludge con¬
sistencies. Light-weight, stubborn suspensions frequently resist settling.
Oils, fats or greases in the waste waters produce low-quality plant
effluents. Varying influent temperatures create upsetting themal cur¬
rents, causing sludge to flow into zones of effluent discharge. Varying
influent rates have a similar destructive effect on effluent quality. Some
clarification equipment cannot operate efficiently at rates greater than
one-half of one-third of its designed capacity. Often sludge cannot be
concentrated to filterable consistencies. Large volumes of thin sludge
create disposal problems. Septicity of sludge in long-period clarification
retention destroys effluent quality.
These operating difficulties indicate that gravity settling clarifica¬
tion and subaqueous sludge formation are not suitable for many kinds
of waste treatment. Despite costly chemical applications and expensive
clarification equipment the settling balance is so delicate that satis¬
factory clarification efficiencies and workable sludge consistencies often
are impossible to maintain. The obvious conclusion is to find means
to tip the balance in the other direction, means for reversing the
usual   procedures,   means   for   obtaining   clarification   by   moving   sus-
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