| May 2008
Plans to gasify solid waste expand
by
Brian R. Hook 
Plans to build facilities to gasify municipal solid
waste are starting to materialize around the country as work proceeds
on a plasma gasification facility in Florida.
The St. Lucie County Solid Waste Baling & Recycling Facility in St.
Lucie County, Florida, which processes nearly 1,300 tons of waste a day,
hopes to start construction on a new plant to turn trash into power in
the next 12 months.
St. Lucie County started its due diligence process to find a permanent
solution for its waste stream over three years ago, said Ron Roberts,
assistant solid waste director. The county researched bioreactors, incineration,
standard gasification, plasma arc gasification, pyrolysis, and other
thermal conversion technology processes.
“After more than 4,000 pages of research, one technology had the staying
power to remain at the top of the list. It was plasma arc gasification,”
Roberts said.
An ionized gas is passed over an electrical arc creating plasma, a super
heated gas more than 5,000 degrees Celsius. This breaks the molecular
bonds and the carbonaceous waste is converted into a synthetic gas of
mainly hydrogen and carbon monoxide.
Atlanta-based Geoplasma LLC, a subsidiary of Jacoby Development Inc.,
is developing the plasma-arc gasification project in St. Lucie County.
The facility, which will be owned and operated by Geoplasma, will cost
approximately $200 million.
The State of Florida has allocated $160 million in
non-taxable bonds for the project. The rest is being financed with equity,
non-taxable and taxable bonds.
“One of the primary objectives of plasma gasification of municipal solid
waste is to recover energy from the waste and we believe no other technology
comes as close to maximizing energy recovery,” said Hilburn Hillestad,
president of Geoplasma.
Each ton of recovered municipal solid waste contains approximately the
same amount of energy as one barrel of oil, Hillestad said. Processing
1,500 tons of solid waste a day at the facility would recover enough
energy to power approximately 55,000 homes.
“We are currently negotiating with a utility to build, own, and operate
the power generation facility. In this model, we would provide syngas
to the utility,” Hillestad said.
“The economics supporting the model are based on processing fees for
the municipal solid waste and the sale of syngas. Both primary components
are sufficient at St. Lucie for the project to be feasible.” The gasification
facility would also sell the by-product, an inert, obsidian-like slag
material for aggregate use in the local area.
Madison, Pennsylvania-based Westinghouse Plasma Corp., a subsidiary of
Calgary, Alberta-based Alter NRG Corp., is providing the plasma gasification
technology, which has been used in Japan to gasify waste for more than
five years.
“We have demonstrated in our plants at Utashinai and Mihama/Mikata that
these plants can operate reliably for many years and with emissions superior
to incineration,” said Thomas Gdaniec, vice president of marketing and
sales at Westinghouse Plasma. 
The Utashinai facility, developed by Hitachi Metals Ltd. in 2003, has
been treating 200 to 280 tons a day of municipal solid waste and auto
shredder residue. Hitachi also commissioned the facility located between
the towns of Mihama and Mikata to process 20 tons a day of municipal
solid waste and four tons a day of sewage sludge.
Both Japanese plasma-arc gasification facilities meet stringent environmental
regulatory requirements, producing extremely low levels of dioxins, Gdaniec
said.
In addition to St. Lucie County, other plasma-arc gasification projects
have been announced that will use the technology. There are plans to
build a facility in New Orleans to convert 2,500 tons a day of solid
waste to produce 138 megawatts of power.
Plans to turn 150 tons of municipal solid waste a day in Koochiching
County, Minnesota into synthetic gas for use at a neighboring paper mill
are underway. Plus, Renewable Fuels of Tallahassee LLC plans to install
another facility in Florida.
Two more plasma-arc gasification facilities are already under construction
in India. SMS Infrastructure LTD is building two 68 tons per day waste-to-energy
plants to use Westinghouse Plasma gasification technology. A project
in Pune, India is scheduled to start operations this summer and another
in Nagpur is scheduled to start this fall.
All of these projects will use the plasma arc technology, which was first
developed by NASA in the 1960s to test the integrity of heat shield materials.
A General Motors Corp. plant in Defiance, Ohio, has been using the technology
for 18 years.
“Our plasma technology is proven. We have extensive proven experience
demonstrating the reliable operation of our plasma torches,” Gdaniec
said.
“The benefits of plasma gasification are the ability to turn a waste
fuel into an energy source, reducing our reliance on fossil fuels and
improving our environment.”
Facility costs vary with location, size of the facility and planned use,
he said.
In addition to municipal solid waste, other feed materials could include
industrial waste, bio-mass, coal, petroleum coke and tires. According
to Westinghouse Plasma, the technology is also suited for hazardous waste,
chemical waste and sediment sludge.
Compared to conventional waste management strategies, plasma gasification
is able to recover more energy from residual waste, according to Westinghouse
Plasma.
Plasma gasification of typical hazardous waste generates almost eight
to ten times as much energy per unit of waste than the energy required
to destroy the waste. The plasma torch itself provides approximately
5 to 10 percent of the heat input into the reactor, minimizing the electrical
power required in the gasification process.
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