The $425 million facility expected to be built in St. Lucie County will use lightning-like plasma arcs to turn trash into gas and rock-like material. It will be the first such plant in the nation operating on such a massive scale and the largest in the world.
Supporters say the process is cleaner than traditional trash incineration, though skeptics question whether the technology can meet the lofty expectations.
The 100,000-square-foot plant, slated to be operational in two years, is expected to vaporize 3,000 tons of garbage a day. County officials estimate their entire landfill — 4.3 million tons of trash collected since 1978 — will be gone in 18 years.
No byproduct will go unused, according to Geoplasma, the Atlanta-based company building and paying for the plant.
Synthetic, combustible gas produced in the process will be used to run turbines to create electricity — about 120 megawatts a day — that will be sold back to the grid. The facility will operate on about a third of the power it generates, free from outside electricity.
About 80,000 pounds of steam per day will be sold to a neighboring Tropicana Products Inc. facility to power the juice plant's turbines.
Sludge from the county's wastewater treatment plant will be vaporized, and a material created from melted organic matter — up to 600 tons a day — will be hardened into slag, and sold for use in road and construction projects.
"This is sustainability in its truest and finest form," said Hilburn Hillestad, president of Geoplasma, a subsidiary of Jacoby Development Inc.
For years, some waste-management facilities have been converting methane — created by rotting trash in landfills — to power. Others also burn trash to produce electricity.
But experts say population growth will limit space available for future landfills.
"We've only got the size of the planet," said Richard Tedder, program administrator for the Florida Department of Environmental Protection's solid waste division. "Because of all of the pressures of development, people don't want landfills. It's going to be harder and harder to site new landfills, and it's going to be harder for existing landfills to continue to expand."
The plasma-arc gasification facility in St. Lucie County, on central Florida's Atlantic Coast, aims to solve that problem by eliminating the need for a landfill. Only two similar facilities are operating in the world — both in Japan — but are gasifying garbage on a much smaller scale.
Up to eight plasma arc-equipped cupolas will vaporize trash year-round, nonstop. Garbage will be brought in on conveyor belts and dumped into the cylindrical cupolas where it falls into a zone of heat more than 10,000 degrees Fahrenheit.