TREATABILITY STUDIES FOR KOPPERS-TOTZEK COAL
GASIFICATION WASTEWATER
R. R. Mannar, Chemical Engineer
Tennessee Valley Authority
Knoxville, Tennessee 37902
INTRODUCTION
As a part of a national effort to develop synthetic fuels, the Tennessee Valley Authority (TVA) in
1979 undertook feasibility studies for a large coal gasification plant to be sited at Murphy Hill in
northern Alabama. Following extensive evaluation of several coal gasification technologies, the Kop-
pers-Totzek (K-T) process offered by Gesellschaft fur Kohle-Technologie (GKT), Federal Republic
of Germany, was initially chosen for the Murphy Hill plant. Since neither commercial nor pilot-scale
K-T gasification facilities exist in the U.S. to date, TVA in collaboration with GKT conducted a
large-scale coal test at the Nitrogenous Fertilizer Industry (NFI) plant in Ptolemais, Greece, with
American coal. The primary test objectives were to procure engineering data for process design and
to characterize several key waste streams to evaluate environmental impacts in the U.S. and for
designing pollution controls.
The aqueous waste streams were characterized in detail by TRW, Inc. and GKT. Following the
characterization work, wastewater treatability studies consisting of biological and physical-chemical
methods were initiated. The purpose of the treatability program was to ascertain that the toxic aqueous
waste streams from the K-T gasification plant can be rendered environmentally acceptable for discharge. The secondary objective was to assist the Environmental Protection Agency (EPA) to promulgate regulations establishing performance standards for the U.S.-based K-T gasification projects.
The treatability program concluded that it is possible to use a combination of biological and physical-
chemical treatment concepts to convert the toxic effluent streams into innocuous streams. However,
in January 1984, due to several inherent advantages, it was decided to replace the K-T process with
the Texaco gasification process. Since then, the Murphy Hill project has been suspended and the site
has been placed in a defense energy reserve status. This paper documents the broad spectrum of the
wastewater treatability program conducted by TVA for the K-T gasification process.
BACKGROUND AND PRESENT STATUS
In 1979, TVA began evaluating the technical, economic, and environmental feasibility of a synthetic fuel facility in the Tennessee Valley region. As a result, a large coal gasification facility processing approximately 20,000 tons per day (t/d) of eastern bituminous coal and producing medium
Btu gas (MBG) was planned to be constructed and operated at Murphy Hill. In 1980, Congress
established the U.S. Synthetic Fuels Corporation (SFC) to provide additional incentives for private
sector ownership. Since 1981, TVA has expended significant efforts towards creating a consortium
of private companies known as the North Alabama Coal-to-Methanol Project (NACMP). The consortium, with TVA's assistance and support has actively sought financial support from the SFC.
Decreasing oil prices and oil consumption have imposed heavy economic constraints on the synfuel
industry making it less competitive with the conventional petroleum industry. By June 1983, to compensate partially for the economic constraints, the plant capacity was reduced to about 3,400 t/d of
coal to produce approximately 2,200 t/d of methanol. The NACMP consortium withdrew its fourth
application to SFC in February 1985.
LARGE-SCALE COAL TEST
Approximately 6,000 tons of Illinois No. 6 coal was shipped to Greece for test purposes. TVA
contracted TRW, Inc. to conduct onsite collection and analyses of several gas, liquid, and solid waste
samples and ship several samples to the U.S. for confirmatory analyses and treatability studies.
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