May 2008

Plans to gasify solid waste expand
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Westinghouse Plasma is providing gasification technology, which has been used in Mihama-Mikata waste-to-energy facilities in Japan for more than five years.

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.