Some of the hardest-to-get-rid-of business
headaches come from things that go wrong only occasionally.
Take the leftovers from making secondary
aluminum from scrap. The dross that forms at the surface has
enough aluminum to be worth its own recycling process, often
done by a different company. Eventually, one is left with a
residue called salt cake, ideally with minimal aluminum but
containing soluble salts from the flux and nonmetallic oxides.
That typically goes to a landfill.
At a reasonably modern landfill, most of the time the stuff
sits dormant. But when Murphy's Law kicks in, the result can be
what Will Flower of Republic Services Inc. refers to as his
company's "$22-million headache."
Approximately 1 million short tons of
aluminum dross residue went to the Countywide Recycling &
Disposal facility in East Sparta, Ohio, starting in 1991, much
of it when Waste Management Inc. was the owner of the 818-acre
site. Waste Management, sold it to third-ranked Republic, based
in Fort Lauderdale, Fla., in 1999. Two years later, Republic
stopped accepting aluminum dross waste at Countywide, and last
year it banned all aluminum wastes at Countywide and extended
its dross waste ban to all Republic facilities in 21
But the accumulated problem at Countrywide
didn't just fade away. "We incurred a $22-million charge in the
first quarter of 2007 to fix the site and comply with orders
from the Ohio Environmental Protection Agency," Flowers told
AMM. "Damage to our reputation and image in the
community is enormous and has negatively impacted our
The overt problem wasn't a health risk, but a
recurrent and pervasive odor. The stuff is fine when dry, but
contact with water can lead to a wide variety of gaseous
emissions, some of which burn underground.
"If a landfill has accepted aluminum
production waste, it is important to watch for indications of a
subsurface fire," Ohio's EPA said in a July advisory. According
to the agency, aluminum production wastes exposed to water can
react and emit toxic, flammable and potentially explosive
gases, including ammonia, methane, hydrogen and acetylene.
"I suspect that salt cake will eventually be
seen as hazardous waste due to problems with leachate
(spreading liquid) and gas generation," said Mark Schlesinger,
a professor of metallurgical engineering at University of
Missouri's Rolla campus who recently wrote a book called
A German company with an offshoot in
Becancur, Quebec, says it can turn secondary aluminum residues
into marketable substances with zero landfill. Michael Romberg,
president and chief executive officer of Agor AG, told
AMM recently that the Becancur facility did test runs
this year for three U.S. aluminum smelting companies.
"Every salt slag is a little bit different.
We processed the salt slags and we have the basis for a plant
layout. We are prepared to build a plant in the United States.
When they are ready, we are ready," Romberg said. One potential
site would serve southern Indiana, Kentucky and Tennessee, he
said. Ohio and the Chicago area are also being considered.
But there is a question mark over whether
potential customers will find that option financially
attractive. "Economy of scale will be important in salt cake
processing," Schlesinger said. "No single aluminum recycling
plant is likely to generate enough of it to justify its own
Agor's Becancur facility was largely closed
from late 2005 to early 2007, partly to adjust the technology
and partly to develop reliable ties with buyers of the output.
The plant, Recyclage d'Aluminium Quebec Inc., started out
recycling aluminum from the primary production dross of Alcoa
Inc. It became German-owned in 2001; the buyer became Agor in
Romberg said Agor's process has four outputs,
two of them being recovered aluminum and a reusable version of
the salt flux inserted at smelters. The hard part is finding a
use for the low-value leftovers. For ammonium sulfate, there is
a fertilizer application. The final component, which Agor
describes as a fine-grained mineral substance with a high
aluminum oxide content, is marketed as an input for cement and
for making the mineral wool used as construction
Meanwhile, landfill owner Republic Services
asked a consultant to test some fire suppressant chemicals on
samples from the smoldering Ohio landfill. None worked. "This
unexpected result is not readily explained," the adviser
A December map of the landfill's underground
temperatures shows readings up to 195 degrees Fahrenheit.