If you live in a single-family home in Arlington, the trash you put out for collection each week eventually comes back to you — in the form of electricity. While the Arlington recycling rate is nearly 50 percent, well above the national average of about 35 percent, that means that there still is plenty of garbage to deal with. All that waste has to go somewhere and much of it ends up at a waste-to-energy plant in Alexandria, near the Van Dorn Street Metro station, that Arlington jointly owns with the city.

Covanta, the company that operates the facility, estimates that they process 975 tons of solid waste per day, distributed among the three 325 ton-per-day furnaces on-site, preventing it from ending up in a landfill.
“In some ways, the U.S. can be seen as a third-world country, with the way we’re putting garbage in landfills,” said James Regan, Covanta’s media director.

Arlington and Alexandria’s municipal waste goes through an emissions-controlled incinerator, where the controlled fire reaches temperatures just under 2,000 degrees Fahrenheit. The fire boils water, which in turn generates steam and, through that, electricity.

That generates about 23 megawatts of baseload power, according to Regan, enough to power about 20,000 homes.
Emissions are monitored throughout the processes, with a few-dozen-or-so knobs, buttons and devices each focused on a different aspect of the process.

With all the capabilities, however, the control room’s goal is threefold: to monitor multiple security camera feeds in case of the occasional, small fire in the trash pit; to monitor temperatures in the combustion chamber; and pollution monitoring and emissions controls.

The combustion has led to a 90 percent reduction of waste by volume, which the company says offsets, on average, one ton of carbon dioxide equivalent for each ton of waste processed.

Both ferrous and non-ferrous metals are able to be extracted from the combustion and recycled, and Covanta is currently developing ways to reuse ash “as aggregate for roadways and construction materials.”

The facility has been burning trash since February 1988, according to Bryan Donnelly, the Arlington/Alexandria facility manager.

Prior to that, there was another incinerator, but it didn’t have the emissions controls or metal recovery program that the current waste-to-energy plant has.

New plants can cost as much as $500 million, but tend to be much larger than Arlington’s plant, which is only four acres — the smallest operated by Covanta. Most other plants are closer to 24 acres, according to Regan.
He estimates that this facility, in today’s dollars, would have cost about $200 million.

To read the full story, visit https://www.arlnow.com/2018/04/06/not-wasting-waste-how-arlington-and-alexandria-turn-trash-into-electricity/.

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