THE VIRGINIAN-PILOT
Copyright (c) 1994, Landmark Communications, Inc.
DATE: Sunday, July 10, 1994 TAG: 9407100073
SECTION: LOCAL PAGE: B5 EDITION: FINAL
SOURCE: ASSOCIATED PRESS
DATELINE: LORTON LENGTH: Medium: 86 lines
Enough electricity to power 75,000 homes flows from the Ogden Martin Systems plant in Lorton - and its fuel is not oil, coal, gas or uranium.
It's broken egg shells, old boards, last week's newspapers, rotten fruit, torn gift wrap, half-eaten sandwiches, chicken bones. It's garbage.
It might be hard to imagine deriving such power by burning trash, but that is what the privately owned energy/resource recovery plant has been doing since June 1990.
``Really, this is a power plant. It has a specialized fuel, obviously, but it's still a power plant,'' said William A. Del Vecchio, its manager of administration.
That's the beauty of the plant, he said. Fairfax County gets rid of most of its garbage, and Ogden Martin Systems of Fairfax Inc. gets fuel for its power plant.
Ninety percent of the profit from the sale of electricity to Virginia Power goes to Fairfax County, and the remaining 10 percent and an annual management fee paid by the county go to Ogden Martin.
The plant is on property owned by the District of Columbia inside the borders of Fairfax County. About 30 percent of the trash burned there comes from the district.
Company officials tout the plant's clever engineering, the high-tech means of scrubbing the exhaust before it's released to the atmosphere, the space the process saves in landfills and the elegance of turning waste into energy.
But visitors always are spellbound by the garbage pit and the giant hand-like grapples, Del Vecchio said.
``They all want to stand here and watch the crane,'' he said.
In a canyonlike room that's taller than a 10-story building and as long as two football fields, one of four massive six-clawed grapples opens its jaws and plunges to the garbage pit below.
The jaws close, seizing four to five tons or so of garbage at a bite. The crane the grapple is attached to moves smoothly over a furnace. With a crash, the garbage falls into the hopper and slides slowly toward the inside flame.
Meanwhile, garbage trucks dwarfed by the scale of the room dump more ``fuel'' into the 40-foot-deep pit. The plant's four furnaces can burn 3,000 tons of refuse a day, and more than 1 million tons a year, Del Vecchio said.
The garbage furnaces are lit by natural gas burners. Even after the burners are turned off, the waste smolders at up to 2,000 degrees. Air pumped into the furnaces stokes the flames, and the moving floor is designed to ensure combustion as complete as possible.
As a result, the waste leaving the furnace is one-tenth the volume and one-quarter the weight of the waste going in, said George Ball-Lovera, the plant manager.
The incinerator is hot enough to disfigure such things as radiators, hub caps, beer kegs, fence posts, engine blocks and guns, but it can't destroy them.
The heat produced is used to make steam for the production of electricity.
The metal walls of the furnaces are made of vertical tubes with water in them. The water cools the walls enough to prevent them from melting away, but the heat is intense enough to turn most of the water in the tubes to steam.
The steam is channeled through two turbines that generate about 90 megawatts of power. The plant itself runs on 10 megawatts, and the remainder, up to 79 megawatts, is sent by transmission lines to Virginia Power.
After passing through the turbines, the steam goes to a condenser, where it changes back to liquid form. The water then begins the circuit again.
Only a tiny fraction of the products of the plant's combustion are harmful, Del Vecchio said. They are removed from the air that leaves the furnaces by state-of-the-art filters.
Despite the pollution-control measures, the plant does contribute to the area's air-quality problems, said Rick Hind, legislative director for Greenpeace's toxics campaign. Even the best air filters and scrubbers do not remove all the harmful products of the combustion of modern materials, he said.
Del Vecchio said the plant meets or exceeds Environmental Protection Agency guidelines.
The emissions from the plant - and just about everything else - are monitored from a control room.
Instruments monitoring the emissions update computer screens every minute, and Fairfax County officials can check the data themselves by connecting a county computer to the power plant's computers by telephone line.
KEYWORDS: ALTERNATE POWER SOURCES by CNB