SUCCESSFUL STORAGE LAGOON ODOR CONTROL FROM AN
INDUSTRIAL ACTIVATED SLUDGE SYSTEM
Richard A. Poduska, Senior Environmental Engineer
B. D. Anderson, Senior Chemist
Tennessee Eastman Company
Kingsport, Tennessee 37662
INTRODUCTION
Odor control has nearly always been a concern in the operation of wastewater collection and treatment systems because the odors are generally unpleasant and may be
considered to be a public nuisance. It has been of importance and necessity, therefore,
that many and varied odor control techniques have been developed for these facilities
during at least the past 80 years.
During the first two years operation of the Tennessee Eastman Company industrial
activated sludge wastewater treatment system, the lagoon storage of aerobically digested
sludge was required prior to completion of the final sludge dewatering and disposal
facilities. This system operated at an average sludge retention time of 20-25 days with an
additional 20 days retention in the aerobic digester, so that a well-digested sludge was
produced. Even so, however, due to anaerobic conditions in the sludge storage lagoons
for extended periods of time during warm weather, a serious odor emission problem
developed. Application of a waste sodium nitrate stream from a local chemical process
was shown to be effective in eliminating the offensive odors.
The odors generated in the sludge holding lagoons were characteristic of an anaerobic
system and included hydrogen sulfide and organo-sulfur compounds. As a result of the
lagoon odor emissions, an intensive laboratory study was undertaken to evaluate the best
practical means for eliminating the odors by treating the lagoons. The results reported in
this study describe this work and the successful full-scale technique employed.
The activated sludge system treats all the industrial wastewater from the manufacture
of chemicals, fibers, and plastics products and consists of three aeration basins, three
clarifiers, a diversion basin, a post-aeration basin, and an aerobic digester. The influent
wastewater load consists of an average flow of 68,130 m3/day (18 mgd) containing
114,000 kg BODj/day (250,000 lb/day), of which nearly 80% of the BOD load consists
of ethanol, methanol, acetone, acetic acid, and isopropanol. An annual average sludge
yield of 0.29 gr sludge/gr BOD5 treated results in a sizable sludge generation of 32,690
kg/day (72,000 lb/day). A detailed description of the wastewater treatment system is
presented by Poduska [1] and is shown in the schematic diagram in Figure 1.
The four sludge storage lagoons were operated to withdraw supernatant liquid as
gravity thickening concentrated the sludge from the feed concentration of approximately
1.2% solids to nearly 3.0%. The supernatant was returned to the aeration basins and
resulted in utilizing the maximum sludge storage capacity in each lagoon. The lagoons
used for sludge storage have liquid depths from 4.5 to 6.1 meters (15 to 20 feet) with
surface areas from 1.1 to 2.8 ha (2.7 to 7 acres). The total lagoon storage volume is
475,000 m3 (125 MG).
LITERATURE REVIEW
Origin, Chemical and Biological Aspects of Odors
The work of Eliassen [2], Heukelekian [3, 4], Baumgartner [5], and Pomeroy and
Bowlus [6] has contributed much to the initial understanding of the fundamental aspects
of hydrogen sulfide production in wastewater collection and treatment systems. Most of
these early studies focused on H2 S generation in sewer networks since that was the
primary source of nearly all wastewater treatment odor problems. Also, it should be noted
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