Plans to use 10,000-degree plasma to vaporize trash into energy face opposition.
Plans to generate power and eliminate landfill waste by ripping trash apart at the molecular level in Florida and California are running into steep hurdles from local opponents.
The initial proposal in Florida, which has since been scaled back by about 80 percent, would have created the largest plasma arc gasification plant in the world. The proposed plant in Sacramento has been set back by a lack of financial details about just how much electricity would be produced and how much trash would be gasified by plasma.
Plasma is a gas that has been partially ionized, meaning that some of the electrons roam freely, giving it unique electromagnetic properties that make it the fourth state of matter. On Earth we are surrounded by the other three states, solids, liquids and gases, but most of the visible universe is made up of plasmas, found inside various stars.
NASA initially harnessed the power of plasma in the 1960's to ensure that spacecraft entering the Earth's atmosphere didn't burn up. Steel manufacturers used the technology to slice up steel. About 20 years ago other groups realized the high temperatures could gasify, not incinerate, just about any material.
Incinerators need oxygen to burn fuel at a relatively low temperature. Gasification, as its proponents are quick to point out, needs very little, if any, oxygen for the reaction. Incineration is a more of a chemical reaction that releases much of the energy inside a fuel.
The best analogy to what happens, says Lou Circeo, a professor at Georgia Tech who helped develop plasma arc technology decades ago, is what happens inside a bolt of lightening.
"Take about two to three feet of a lightening bolt and attach it to one of these arcs, and this will melt or gasify just about any material," said Circeo.
To gasify trash, gas is expelled from a torch at temperatures hotter than the surface of the sun, higher than 10,000 degrees Fahrenheit. The gas, which is technically plasma, rips matter apart physically and reforms it into two products, a gas and a solid. The solid slag can be ground up and used as filler material in construction projects.
The resulting gas, a mix of carbon monoxide and hydrogen called synthesis gas or syngas, can then be burned to produce electricity or turned into various petroleum products.
"The greatest benefit of gasification is the ability to recover more usable energy out of the waste material," said Mark Montemurro, CEO of Alter NRG, which holds the licence to the technology that would be used for the California plant. "It's twice as efficient as combustion."
That's not all that is produced in the reaction, points out Ron Saff, a doctor and member of Physicians for Social Responsibility who recently wrote an Op-ed in a Florida newspaper opposing a plasma arc gasification plant in St. Lucie, Fla. Plasma arcs also produce dioxins and other toxins harmful to human and environmental health, which is why Greenpeace also opposes the plant.
"All the engineering problems should be worked out on a small scale before they build [plasma gasification plants] on a larger scale," said Saff. "The people of St. Lucie County don't want to be guinea pigs."
Saff also questions energy production claims from two gasification plants operating in Japan, and argues that recycling could solve St. Lucie's trash problem.
Montemurro says the technology has already been worked out in the Japanese plants and is clean, healthy and environmentally friendly. Recycling is great, and Montemurro supports it, but there are some things that can't be recycled and our energy needs are still growing.
"I think that more plants will eventually go up," said Montemurro. "Everyone recognizes that oil is a decreasing supply, and we have to look for other sources of energy. Why not gasify stuff that you can't otherwise use?"