4    A Case History of the Design, Construction and Startup of a
System for Biological Treatment of Wastewater From a New
Ethanol Production Plant
W. Vince Lord, Jr., Environmental Supervisor
Tennol Energy Company
Jasper, Tennessee 33347
J. G. Walters, Principal Engineer
Infilco Degremont, Inc.
Richmond, Virginia 23229
James E. Smith, Jr., Project Engineer
Harbert International, Inc.
Birmingham, Alabama 35201
INTRODUCTION
The Tennol Energy Company constructed and started a new ethanol production plant near Jasper,
Tennessee, which was completed in late 1985. The plant first produced alcohol in December, 1985,
from the same feedstock as used for centuries by the inhabitants of Tennessee for making their
famous sourmash bourbon, namely, corn. Because of its location in a very pristine valley and a small
community of 4,000, Tennol was required to construct a pretreatment plant to reduce 8,000 mg/L
BOD by 97% before discharge 'o the city of Jasper wastewater treatment system.
Annual alcohol production is 25 million gallons per year with the byproducts of C02 being sold to
nearby gas distributors, and the distillers dried grains with solubles (DDGS) being marketed as animal
feed.
The alcohol production facilities as engineered by Lummus Crest, Inc., Bloomfield, New Jersey,
were based on technology from Buckau-Wolf, a Germany-based company. The design and selection
of equipment for the wastewater treatment plant was the responsibility of Infilco Degremont, Inc.,
Richmond, Virginia, with construction by Southland Power Constructors, Birmingham, Alabama.
Buckau-Wolf technology of thick mashes creates a smaller volume of wastewater but results in a
higher concentration of BOD5. The waste loading of 0.3 lb BOD/bushel is slightly lower than that
found in other ethanol plants using a corn feedstock.
This case history will present, in detail, the evaluation of various systems and the rationale for the
selection of a methanization system for the first-stage treatment followed by a low F/M (food to
mass) activated-sludge system. This paper will also discuss system design, startup experiences, actual
versus estimated wastewater characteristics, and operating results available to the date of the paper
presentation.
TREATMENT REQUIREMENTS
Tennol's plant is officially designated a pretreatment plant since the waste after treatment is discharged to the City of Jasper's collection system and wastewater treatment facility. The Jasper system
of aerated lagoons has a design capacity of 0.78 mgd of domestic sewage at 250 mg/L BOD. Prior to
Tennol's discharges, the Jasper plant received an average of 0.2 mgd. Jasper's plant, therefore, had
capacity to accept the pretreated wastewater from Tennol provided the BOD and suspended solids did
not exceed 250 mg/L.
BASIS FOR DESIGN
Since there is not another plant operating with the exact technology that is used in the production of
alcohol by Tennol. there was no opportunity to adequately characterize the waste or conduct pilot
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