Batch Treatment for Industrial Wastes
ROBERT L. IRVINE, Associate Professor
RICHARD O. RICHTER, Graduate Student
Department of Civil Engineering
University of Notre Dame
Notre Dame, Indiana 46556
THOMAS P. FOX, Facilities Manager
QLM Laboratories, Inc.
Nyack, New York 10960
INTRODUCTION
The national goal of the Federal Water Pollution Control Act Amendments of 1972
(P.L. 92-500) is that the discharge of all pollutants into navigatable waters be eliminated by
1985. To meet this goal the Environmental Protection Agency (EPA) was required to
publish Federal standards of performance for treatment for a list of categories of sources as
delineated by the Act. The first step was to publish standards that could be met by
application of the best practicable control technology currently available (BPCTCA). For
many industries and most munitipalities BPCTCA means biological waste treatment.
Conventional biological waste treatment may be accomplished in either Activated
Sludge or Trickling Filter plants. The more recent trend is to employ activated sludge
systems. These systems are operated on a continuous flow basis. Because of variations in
flow, total waste strength and make-up of the pollutants in the waste flow, activated sludge
systems with equalization, while recommended by the EPA as BPCTCA, cannot, in many
cases, consistently meet the standards established by the EPA. In most situations,
equalization systems cannot effectively dampen large variations in waste strength if they are
designed for hydraulic equalization with no organic removal. Design for waste strength
equalization in these cases may lead both to excessive expenditures and to operation and
maintenance problems.
Biological waste treatment is likely to be the only economical and perhaps the only
feasible way to remove many organic compounds in wastewaters. This is not meant to
undermine the rather excellent work that has been done in the physical chemical treatment
area. In fact it is stated with the understanding that certain classes of organic compounds
cannot be removed in biological waste treatment systems. This is demonstrated time and
time again with treated effluents which have a five day biological oxygen demand (BOD5) of
less than 20 mg/1 and a total organic carbon (TOC) concentration of greater than 100 mg/1.
As advances are made towards a zero discharge goal, economics of treatment will not
be overlooked. Combined biological and physical-chemical treatment systems of the future
will be able to take full advantage of the removal capabilities of both treatment approaches.
High loaded biological systems will be designed to perform the function for which they are
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