58    APPLICATION OF A KINETIC ANALYSIS USING HISTORIC
OPERATING DATA TO REDESIGN AN INDUSTRIAL
ACTIVATED SLUDGE SYSTEM
John H. Koon, Vice President
Engineering-Science, Inc.
Atlanta, Georgia 30329
Fred L. Boggs, Senior Environmental Consultant
Charleston, West Virginia 25309
INTRODUCTION
A number of factors are forcing the redesign of industrial wastewater treatment systems. Among
these are: (1) more stringent effluent limits, (2) increased waste loads, and (3) requirements to replace
earthen basins with tanks which meet RCRA land ban regulations. This paper discusses methods used
to redesign the wastewater treatment system at an organic chemicals plant. Specifically, the industry
desired to replace existing earthen aeration basins with optimum sized "tanks" that would meet RCRA
land ban standards. This would also necessitate the construction of a new aeration system.
The problem reported in this paper was to work with industrial representatives to determine the size
aeration tank and aeration system needed to effectively treat the wastewater. The approach employed
was to use historical data coupled with conventional activated sludge system kinetic models to determine the size of system components needed to consistently meet permit limits.
The investigation was facilitated by a very complete record of plant operating data. The following
data were available:
• Influent Wastewater Flow.
• Influent TBOD (total 5-day BOD).
• Effluent TBOD.
• MLSS and MLVSS.
• Effluent TSS.
• Aeration Basin Temperature.
• Aeration Basin Dissolved Oxygen Concentration.
• Aeration Basin Volume Employed (the system consisted of two aeration basins; not all
basins were operated all of the time).
Climatological data for the area was obtained from the United States Weather Service. The performance and operating data were divided into two periods: an 18-mo period comprised of the most
recent 18 mo, and a second period comprised of the previous five-year period. The most recent 18 mo
of data was considered the most accurate by plant personnel.
A schematic illustration of the treatment system is presented in Figure 1. Briefly, the system consists
of a 1.5 MG spill control tank, two equalization tanks having a total capacity of 6 MG, pH control,
primary clarification, activated sludge aeration in two basins having a total volume of 8.8 MG,
secondary clarification, and sludge handling. An overview of operating and performance data for the
system is presented in Table I.
PROCEDURES USED TO DETERMINE AERATION TANK SIZE
Operating data from the existing plant were evaluated to assist in making decisions regarding the
size of the new aeration tank and the aeration system. Models used were those developed by Ecken-
felder1 and design procedures developed by AWARE.2
Operating data over the 18-mo period formed the primary basis of this evaluation. Data collected
during the additional 5-yr period were also evaluated with respect to aeration basin sizing.
Based on extensive work sessions with plant representatives, the following assumptions were made:
48th Purdue Industrial Waste Conference Proceedings, 1993 Lewis Publishers, Chelsea, Michigan 48118. Printed in
U.S.A.
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