Up in smoke
January 5, 2012
By Paul Giblin
BAGRAM, Afghanistan -- U.S. Army of Engineers personnel are constructing a $5.5 million trash disposal plant at Bagram Airfield to replace a trash disposal plant that threatens aircraft safety at the international base.
Currently, most trash generated at the base is burned in open pit or in several small incinerators that are located just 300 yards beyond the runway. Bulldozers constantly shovel rubbish into the fire, creating thick columns of brown smoke.
Documents with sensitive data are burned nearby at a complex with several incinerators housed in shipping containers. They pipe out columns of smoke as well.
The threat to aircraft operations is threefold: The smoke hinders visibility for pilots, the heat lifts debris into the air, and the piles of garbage attracts birds that cross the flight path.
Furthermore, particularly during colder months, the smoke creates a putrid fog that hangs over large swaths of housing areas at the base and the adjacent village of Bagram.
It's a high-profile project.
"This is the No. 1 priority to get this turned on, because we have to get that garbage away from the airfield because of the hazards," said Corps of Engineers construction representative Keith Benson of Norfork, Va.
A key factor to the new garbage disposal plant is that it's located about a mile from the runway, military housing and the village. In addition, the twin incinerators at the facility burn at 1,800 degrees Fahrenheit, which produce less smoke than the smaller, cooler-burning incinerators near the runway.
The 10-acre facility features a large covered and lighted sorting facility, where employees working by hand will sort through trash, to separate recyclable material from true rubbish. From there, the remaining trash will placed into the receiving bins of two commercial-grade incinerators that were manufactured by Consutech Systems in Richmond, Va.
The construction work is being handled by the firm EMTA AFCON JV, which is based in Ankara, Turkey. Construction started in October 2009 and is expected to be complete within weeks, if not days.
The incinerators are fired with fuel similar to jet fuel and have the capacity to torch 32 tons of trash a day. The process to start them and heat them to the proper temperature takes more than a day. Once the units hit 1,800 degrees, workers will keep them operational 24 hours a day.
"Once you get these incinerators hot -- 1,800 degrees, I mean that can burn up anything -- there is constant pressure to push it through the system," Benson said.
Workers start the process by dumping non-recyclables into large compartments on one side of the incinerators. Then trash is pushed into the brick-lined burning chambers, pushing forward trash that previously had been placed into the ovens.
Generally, it takes about seven hours for items to process through the burning chambers, Benson said. The resulting ash emerges from the other end of the chambers where it is mixed with a water-based solution and compacted into soggy cubes about three feet tall.
The ash cubes are stored on a concrete pad to cool for two or three hours, then deposited into a pit lined with a rubber membrane for eventual burial. Pipes underneath the pit siphon the excess liquid, which is filtered.
The mountains of trash are so monumental that Corps of Engineers officials are considering whether to bring some of the smaller shipping container-size incinerators to the new plant until they've torched the excess, Benson said.
"There's just so much trash to burn. It's a big operation," Benson said.
After burning the backlogged trash, the incinerators' 32-tons-a-day capacity will keep pace with the daily trash production on the base, he said.
Because the new incinerators burn at such high temperature, they produce far less smoke and ash than the older incinerators. So not only will the smoke be further away from the runway and the population centers, there simply will be less smoke.
The plant also features an administration building, fencing and other anti-terrorism measures.