Dispersed Growth Aeration of
Protein-Glucose Mixtures
E. J. Struzeski, Graduate Student
N. L. Nemerow, Associate Professor of Civil Engineering
North Carolina State College
Raleigh, North Carolina
Dispersed growth aeration is a process of biochemical oxidation
especially suited for the treatment of soluble organic wastes. It is
not recommended for the treatment of sewage and is in no way a
substitute for the activated sludge method of treatment. Dispersed
growth aeration involves the oxidation of soluble organic matter by
dispersed bacteria. Adsorption on large floes is not necessary when
dealing with highly dissolved food material. In many instances it has
been difficult to build up a suitable concentration of suspended solids
when treating a soluble organic waste. Considerable expense and
attention must be given to an oxidation process utilizing a high
concentration of suspended solids. For these main reasons oxidation
by dispersed growths in an absence of large, flocculent growths is
recommended for treating soluble organic industrial wastes.
This process has been reported to be effective in oxidizing
many types of industrial wastes (1, 2, 3, 4, 5, 6, 7). Some basic
theories and results have also been discussed (8) concerning the dispersed growth oxidation of glucose. Since many industrial wastes
contain some proteinaceous matter, the effectiveness of this process
in oxidizing such wastes was investigated. Laboratory studies using
pure proteins were carried out with this objective in mind.
method and procedure
Three proteins; casein, hemoglobin and gelatin were used for
evaluating the effect of proteins on dispersed growth aeration of
glucose. Gelatin and casein were selected because of their relatively
simple chemical structures, known compositions and common occurrence in proteinaceous wastes. Hemoglobin was selected because
of its natural occurrence, mainly in wastes containing blood.
The apparatus consisted of a number of 6-inch diameter lucite
cylinders with approximate capacities of 11 liters. Air was applied
through diffusors located at the bottom of the containers.
145