Zapping trash with man-made lightning
With landfill space at a premium, a group of scientists think they have a solution: a machine that turns trash into small pellets and fuel. But is it practical? Janet Babin explores the debate over plasma gasification.
Plasma gasification test facility at Integrated Environmental Technologies. (Courtesy Integrated Environmental Technologies)
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Scott Jagow: It's time now for our final segment of Consumed -- a special series airing this week on American Public Media programs. We've pointed out how consumer spending fuels our economy, and how many problems we've created from constantly buying new things.
Today we ask: Have we made such a mess that we'll be forced to innovate our way out of it? From our innovations desk at North Carolina Public Radio, Janet Babin looks at a technology that can zap our trash into thin air.
Janet Babin: This new trash technology is based on something as old as the sky:
Sound: (Thunder)
Not the thunder, but the lightning that makes it. And in this case, the lightning is contained inside a reaction chamber, and the bolt never ends. This man-made lightning is so hot, most things put inside the chamber completely vaporize in seconds.
The technology's called plasma gasification, and proponents say it could be the answer to our growing trash problem. Although it uses intense heat, developers say the process is not a new spin on incineration -- commonly used for waste disposal in the past, but discontinued because of emissions concerns.
The process uses intense heat, but developers insist it's not incineration. The "not-in-my-backyard crowd" has complained for years about emissions from burning trash.Dan Cohn: It's a non-combustion process. The waste is not burned, it's converted.
That's Dan Cohn of MIT. He was part of the team that developed the technology for the company Integrated Environmental Technologies. IET, in turn, has created a device that can reduce a ton of trash down to five cubic feet in less than a minute.
To see how it worked, I took some of my own trash -- an old sneaker -- and headed up to Richland, Washington, where IET demos its plasma melter.
The stainless-steel chamber where the lightning happens is about five feet long by three-and-a-half-feet wide. Before the sneaker can go inside the chamber, it has to be shredded. So IET's president Jeff Surma and four engineers take a band saw to it.Jeff Surma: Andy looks like he's having fun here... Yea. How many engineers does it take to shred a sneaker?
Now for the fireworks. Surma picks up the play-by-play:
Surma: It's going into the plasma zone... So first, the shoe gets pre-processed in the gasifier, and then what doesn't get completely gasified there gets dropped into the high-temperature plasma zone.
That plasma is about the temperature of the sun. Most of the sneaker is vaporized in seconds -- the rest comes out looking like a blackish glass bead. IET says beads like this can be used as fill in road construction.
Since it was mostly plastic, the sneaker also created about four gallons of gas that could be used to make alternative fuel. Jeff Surma says rising energy prices have more firms interested in his invention.
But plasma melters are still rare in the U.S. Dr. Robert Do with the Solena Group says that's because the new technology threatens two powerful industries:
Robert Do: The landfill people and the incinerators. So waste company do not want to see this technology come out. On the other hand, if we produce power we will be infringing on the coal business and fossil-fuel burning business.
Critics say plasma technology uses too much energy and is too expensive. And Steve Boton with McDonough Braungart Design Chemistry says the technology could send the message that trash is OK -- kind of the opposite of reduce, reuse, recycle.
Steve Boton: We see waste as a signal of design failure, because products and materials can ideally be designed so they can maintain their flows within closed loops.
In other words, products that can be recycled into items with second and even third lives. But transforming all consumer goods into products like that is a long way off. In the interim, plasma gasification might be the best way to shrink our growing trash problem, with technology as elemental as lightning.
I'm Janet Babin for Marketplace.
