Frederick looks to Montgomery for trash example

Dickerson ‘waste-to-energy’ plant burns 1,500 tons of trash each day, which is then turned into electricity

Thursday, March 2, 2006

Click here to enlarge this photo photos by Tom Fedor⁄The Gazette A claw drops trash in the refuse pit at the Montgomery County incinerator in Dickerson (above left). The Northeast Maryland Waste Disposal Authority owns it on behalf of the county and Covanta Energy operates it. Click here to enlarge this photo Pictured above is the incinerator unit, called a ‘‘Martin stoker.”

The Montgomery County Resource Recovery Facility is tucked away in the rural countryside of Dickerson and looks much like any typical large-scale industrial plant.

On a tour of the waste management facility provided to The Gazette, officials made it clear that “waste-to-energy“ is more than just burning trash.

They stress that the facility, which many call an incinerator, is not actually an incinerator. Those facilities were typically used to burn trash before the 1970s.

“Incinerators are associated with old technology,“ said Joseph LaDana, senior engineer with Montgomery County’s Department of Public Work and Solid Waste Services. “Waste-to-energy made its hay day in the mid-1970s and they’re not incinerators. Incinerators just dispose of trash. They didn’t use a lot of science. Here we have a lot of computerized controls.“

The operation at the Montgomery County facility burns 1,500 tons of trash per day that is generated into electricity. The burning capacity of the plant is 1,800 tons per day, 365 days a year.

The plant uses a special furnace design to burn trash. Heat from the combustion process converts water to steam that is sent to a turbine generator to produce electricity.

The plant generates 55 megawatts per day of electricity, which is exported to provide enough power for 40,000 homes and businesses. The county receives 92 percent of the facility’s electricity sales revenue to offset the operating costs of the plant, LaDana said.

On Monday’s tour was Michael Marschner, the director of Frederick County’s Utilities and Solid Waste Management.

Marschner has been studying a waste-to-energy facility for Frederick County for some time. The Frederick Board of County Commissioners agreed to authorize the Northeast Maryland Waste Disposal Authority to develop a plan for this type of facility, negotiate an agreement with a provider and present the contract to the board on or before Dec. 1.

The board’s decision is a result of recommendations made in a study released in October by the authority and its consultant, R.W. Beck, suggesting the county build a waste-to-energy facility. No final decision on whether Frederick County will go with a waste-to-energy facility has been made at this time.

Marschner sees the Montgomery County facility as a good example of disposing of waste.

“I’ve been in the solid waste business for 30 years and I can assure you the old incinerators and what you see today is completely different,“ Marschner said. “It’s taking a reusable material [trash] and making a commodity...This [Dickerson plant] is an energy facility that uses municipal waste as fuel. It’s always reusable energy because trash is always generated ...This is not your parents’ incinerator.“

For example, air from the “combustion chamber“ goes through air pollution controls. In addition, air is injected through the front and rear walls of the furnace to help with pollution controls.

Montgomery County’s trash

Before the trash comes to the facility in Dickerson, it is first delivered to the Shady Grove Transfer Station in Derwood. It is compacted into steel waste containers and loaded onto railcars. Each day, trains make the 22-mile trip to Dickerson, where the trash is loaded and trucked on-site to the facility’s enclosed refuse building.

Montgomery County does not allow trash from outside the county to be shipped in.

Residue or ash that remains from the burning process is loaded into 20-foot steel containers and shipped by rail to a landfill in Brunswick, Va.

After processing at the Dickerson plant, the ash transported is roughly equivalent to 10 percent of the original waste brought to the facility.

LaDana said the rail system allows the county to eliminate truck traffic along the rural roads leading up to the Dickerson facility.

“We don’t have the trucks rushing in and out,“ he said. “We also used totally enclosed containers so we have no real litter problems around here.“

Environmental advantages

The Dickerson plant is much like the 89 other “waste-to-energy“ facilities located across the country. Trash experts contend they are reliable, clean and designed with modern pollution controls. They must meet state and federal environmental standards not used in incinerator plants operating before the 1970s.

For more than 20 years, they have also been recognized as an energy source — electricity.

The heart of the Dickerson facility is the computer control room, where workers monitor the plant operations 365 days a year. A total of 70 workers, six to a 12-hour shift, use computers to monitor the environmental conditions of the smoke stack that releases carbon dioxide, water vapors and nitrogen from the atmosphere during the burning process.

“The computers control the entire operation,“ said Greg Mullen, supervisor of the computer control center, “every part of the plant and every transmitter.“

According to Mark A. Freedman, facility manager, as the temperature for burning reaches 1,800 degrees, dangerous gases are destroyed before they flow through the chimney stacks.