DESTRUCTION OF PCB CONTAMINATED
FUEL OIL IN AN ALUMINUM MELTING FURNACE
Marshall K. Sonksen, Staff Environmental Engineer
Aluminum Company of America
Davenport, Iowa 52808
Stephen P. Busch, Chemical Engineer
U.S. Environmental Protection Agency, Region VII
Kansas City, Missouri 64106
BACKGROUND
Aluminum Company of America (Alcoa) is the world's largest producer of aluminum and aluminum products. With corporate offices in Pittsburgh, PA, it has mining, smelting, and fabrication
facilities around the world. The company's Davenport Works is a major rolling mill on a 445 acre site
on the banks of the Mississippi River in Davenport, Iowa. This facility, over one mile in length, has
approximately 120 acres under roof.
The heart of Davenport Works is its hot rolling operation used to reduce aluminum ingot into flat
plate and coiled sheet. The facility also houses a multitude of ancillary equipment. This includes preheat, reheat, and annealing furnaces along with aluminum melting and holding furnaces. Like most
industries that have high temperature operations, Alcoa's Davenport Works requires hydraulic fluids
that have the ability to maintain physical properties at high temperature and that provide maximum
protection against fire. From about 1960 to 1972, an additive in these fluids was polychlorinated
biphynels (PCB's).
In early 1979, when environmental concerns surfaced regarding the use of fluids containing PCB
in concentrations over 50 mg/1, Davenport Works environmental engineering department initiated a
comprehensive survey of the hundreds of hydraulic systems throughout the plant. Only a handful of
the systems were found to contain residual PCB over 50 mg/1. But those few, along with the knowledge that past practice had been to use PCB fluid in most high temperature applications, led to the
testing of the Work's supply of scrap oil accumulated over the years as auxiliary fuel for aluminum
melting furnaces.
Samples of the auxiliary fuel were collected and submitted for analysis. These, along with additional samples collected for verification, confirmed the worst. There was, in storage, 1.6 million gallons of high quality scrap oil that contained an average of 350 ppm PCB. In just a few months, with
the July 1, 1979 effective date of the newly promulgated PCB regulations, a one-million dollar inventory of carefully accumulated auxiliary fuel would turn into a multi-million dollar liability. Table I
sets out the physical characteristics of the auxiliary fuel supply.
THE OPTIONS
In 1979, as today, there were limited options for the proper disposal of PCB contaminated liquids.
These included incineration or land disposal at one of the few EPA permitted facilities, but the going
rate exceeded one dollar a gallon plus transportation. In addition to the cost factor, however, Alcoa
was concerned with the environmental risk and associated liability connected with loading and transporting nearly 1.6 million gallons of PCB liquid to a distant EPA permitted facility.
An option of interest was the regulatory authority (40 CFR 761.60(e) of each EPA Regional
Administrator to approve an alternate disposal method if sufficient PCB destruction efficiency could
be achieved. To investigate the viability of this option, and since one melting furnace had not yet been
converted back to gas, Davenport Works speedily conducted four PCB emission tests on a melter
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