Treatment of Brewery
Wastewater by High Rate
Biological Process
W. WESLEY ECKENFELDER, JR., Professor
Vanderbilt University
Nashville, Tennessee
ALAN H. PLUMMER, JR., Project Manager
Forrest and Cotton, Inc.
Dallas, Texas
INTRODUCTION
Breweries are generally located in the vicinity of a municipality which provides
them with the choice of either treating their waste separately or executing an agreement with the municipality to treat the brewery wastes along with the domestic
wastes. Combined treatment has been accomplished with the brewery paying a surcharge to cover the cost of treating its wastes (1). The combined treatment alternative is often attractive to breweries since the domestic wastes can provide nutrients
required for treatment of the nutrient deficient brewery wastewater.
The quantity and quality of brewery wastewater will depend to a large extent
on the in plant process of the particular brewery. Brewery wastes are composed
mainly of liquor pressed from the wet grain, liquor from yeast recovery, wash water
from various operations, and spent grain.
In addition to exerting a relatively high BOD and to containing significant
concentrations of suspended solids, a deficiency of nutrients is another characteristic
of the brewery wastewater (2). Also, alkalinity has been observed to be relatively low
which can result in undesirable pH levels.
It has been shown in lab studies and full scale treatment operations that the
wastewaters discharged from breweries are amenable to biological treatment.
Eckenfelder and Bueltman determined by laboratory studies conducted with
batch units that wastewaters from the brewing operation, as well as the packaging
operation, are amenable to biological oxidation (3,4,5). Reduction of BOD greater
than 90 per cent were attained with aeration periods of three to six hr. The studies
also indicated that primary sedimentation to remove solids may be required depending on the suspended solids concentration encountered. Design parameters developed
from the laboratory studies are consistent with results obtained from other organic
wastes.
Ford and Eckenfelder observed that brewery wastewater was successfully treated by laboratory bench scale activated sludge units (6). This study concluded that
the best sludge settleability for a brewery waste was obtained between loadings of
0.2 and 0.7 BOD/day/lb MLSS. During the study, filamentous organisms present at
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