The Use of Biological Waste
Treatment Systems for the
Stabilization of Industrial Wastes
ROSS E. McKINNEY
Assistant Professor of Sanitary Engineering
Massachusetts Institute of Technology
Cambridge, Massachusetts
The economic disposal of dilute organic wastes is one of the major
problems facing industry today. The volume and the nature of the
organic wastes being produced by many plants are such that the receiving
body of water is not able to assimilate the wastes without creating
nuisance conditions. Municipal sewage treatment plants are not always
available or of sufficient capacity to handle both the domestic sewage
and the industrial wastes. In either case the industry must reduce the
strength of its organic wastes to such an extent that the wastes can be
satisfactorily disposed into municipal sewers or to a receiving body of
water. Biological treatment is the most efficient method for reducing
dilute organic wastes since it is possible to obtain any degree of purification required. Unfortunately, it is not always easy to decide on the
best type of biological treatment for a particular industrial waste. It
is the purpose of this paper to briefly set forth the characteristics of the
major biological waste treatment systems as a guide in the selection
of the proper treatment units.
The four biological treatment systems in operation today are anaerobic digestion, oxidation ponds, trickling filters and activated sludge.
The basis for all four systems is the same. The microorganisms in each
system utilize the organic matter in the wastes for the production of
new cells and for energy to remain alive. The organic matter which has
been converted into new cells has not been completely stabilized but
merely transformed from one chemical structure to another. The
organic matter which has been utilized for energy and converted into
carbon dioxide and water has been completely stabilized. It can readily
be seen that the two problems in biological waste treatment systems
are the removal of the organic matter from the waste waters and the
removal of the microorganisms which have been created in the first
phase.
465