EPA turning debris to ashes

Tag : special use blower

Seeking ways to stem the flow of tons of storm-related constructionand demolition debris to area landfills, the EnvironmentalProtection Agency is conducting a pilot project in St. BernardParish to see whether the debris can simply be turned to ashes.
An EPA team burned vegetative and construction debris this week ina special incinerator called an "air-curtain destroyer" at theparish's Paris Road landfill site, a "test burn" to determine theincinerator's efficiency.
"We're looking at how much volume reduction will actually beachieved," said Nancy Jones, an EPA project manager. "We're alsogoing to be looking at the ash to determine if it's a hazardousmaterial or not."
None of the debris contains asbestos, Jones said. In February, theEPA received approval from the St. Bernard Parish Council to testthis method on debris that contained asbestos. However, Jones saidthe project team decided to conduct these initial tests, thenpotentially experiment with asbestos if this week's results arefavorable.
"We need to wait for the results to come in and make an evaluationas part of our final report," she said. "Instead of usinghypothetical numbers (in asbestos tests), this way we can use realnumbers."
The key improvement on open burning would be volume reduction.According to a past report, air curtain burning results in 110pounds of ash for every 100 tons of vegetative debris burned,compared with 2,550 pounds after open-air burning. On Tuesday, theEPA team burned about 80 tons of vegetative debris such as treebranches. After burning, the debris was reduced to ash that filledabout one-third of a large commercial trash bin. The team is stillevaluating its effectiveness with demolition debris, but hadsimilar results. Burnings on Wednesday and Thursday included debrisfrom a demolished building, including items such as furniture.
The air curtain destroyer is essentially a large box like acommercial trash bin. A blower forces the air inside the box torecirculate, raising the temperature and reducing waste volume,said Bob Olexsey, an EPA project manager. The device does not emitsmoke, only heat. The technology is widely used in the UnitedKingdom to clear livestock carcasses infected with hoof and mouthdisease.
While the state could authorize its use at any time, Jones saidofficials simply wanted more data on the effectiveness and safetyof the process. The technology was briefly considered by OrleansParish in the months following Katrina, but was never implemented.It was used in Florida after Hurricane Andrew in 1992, but theoperation was shut down after two weeks because of protests andenvironmental concerns. This is the first extensive U.S. testingdone on the technology, Jones said.
"I could understand why people were concerned when there hadn'tbeen a thorough evaluation done on the technology," she said.
Because of those concerns, one of the team's primary focuses isemissions. Olexsey said the burn area is surrounded by two rings ofmonitors to measure air quality and the team keeps a close eye onwind direction. The burnings will be suspended if the wind shiftsthe emissions toward populated areas, he said.
"We know the emissions aren't harmful," Jones said. "But we'repolicing ourselves for public perception reasons."