30    TREATABILITY OF TWO DIFFERENT
INDUSTRIAL WASTEWATER STREAMS USING THE
ANAEROBIC MIGRATING BLANKET REACTOR
James J. Flamming, Graduate Research Assistant
Largus T. Angenent, Graduate Research Assistant
Shihwu Sung, Adjunct Assistant Professor
Richard R. Dague, Professor (Deceased)
Iowa State University, Ames Iowa 50011
ABSTRACT
Treatability studies were conducted on two different industrial waste streams using a new-
compartmentalized, high-rate, anaerobic reactor system known as the anaerobic migrating blanket reactor (AMBR). During the first experimental run, studies were conducted on a 4:1 mixture
of cardboard recycling plant wastewater and industrial grade bioenzyme plant wastewater. Later,
a second experimental run was made using the cardboard recycling plant wastewater by itself.
Soluble chemical oxygen demand (SCOD) removals of 78% were achieved at a COD loading
rate of 8 g/L/day while treating the combined waste stream, and 72% at a COD loading rate of 10
g/L/day while treating solely the cardboard recycling wastewater. Additional studies suggest that
compartmentalized reactors such as the AMBR can provide additional sites for the metabolism of
higher energy organics that accumulate during shock-loading conditions.
INTRODUCTION
Most municipalities utilize aerobic biological processes in the treatment of large, relatively dilute combinations of domestic and industrial wastewater streams. Anaerobic treatment used is
usually in the form of digesters for final stabilization of resulting sludge streams. However, the
treatment of industrial waste streams by the same methods can become costly. In general, industrial wastewaters are higher in concentration than domestic, or domestic/industrial blends that
occur at municipal wastewater treatment plants. This increased organic concentration results in
increased aeration requirements, increased reactor size, and increased production of waste
sludges, which themselves require further treatment and stabilization. In addition, industrial
waste streams can vary greatly with respect to waste strength and quantity of flow. These fluctuations can also result in large variations in the oxygen requirements and sludge production of the
aerobic systems. Fluctuations can occur rapidly over a short period of time or slowly over an entire season, and depend on the productivity and use of raw materials by a particular industry.
In some cases, biological alternatives must be discarded altogether due to the inhibitory or
even toxic nature of the waste. In such cases, physical/chemical treatment methods may be used,
but many times these can be quite costly to operate. Thus, many industries simply decide not to
investigate industrial pretreatment methods at all. but rather, opt to pay high sewage use fees. As
a result, the municipality becomes responsible for the ultimate stabilization of the waste. By discharging their waste to the sewers, the strength of these streams becomes diluted, and the effects
of high strength/high variability/inhibitory constituents are minimized.
While many industries feel forced to live by this method, cost-effective wastewater treatment
alternatives do exist in the form of anaerobic biological systems. These systems can undergo
high organic loading rates typical of industrial waste streams without large increases in costs. In
fact, the higher the strength of the waste stream, the more potential profit is available due to
52nd Purdue Industrial Waste Conference Proceedings, 1997. Ann Arbor Press. Chelsea. Michigan 48118. Printed in
U.S.A.
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