Written by: Marlene Taylor, Special to Gannett Tennessee
Sorting 70 tons of plastic milk jugs, beverage bottles, tin and aluminum cans and all manner of paper is a seemingly impossible task. But RockTenn does it every day.
The Proctor Street facility sorts and bales 1,700 tons per month of what once was dumped into landfills. With the help of the city of Knoxville's new Household Curbside Recycling program, 450 tons of that originate from city residents.
Beginning in October, 20,000 residents signed up to receive a 96-gallon cart for single-stream recycling. All recyclables go in the cart in a leave-the-sorting-to-us system.
For those initial 20,000 residents, the program was long-anticipated.
RockTenn partnered with the city of Knoxville and Waste Connections to make the program happen, and the results are significant.
John Homa, solid waste project manager in the city's Public Service Department, says that in June 2011, about 3,950 tons of refuse - including recoverable products - went to the landfill.
In June 2012, that figure dropped to 3,255 tons - a 695-ton decrease.
Some fairly complex equipment makes single-stream recycling possible. At RockTenn, the hodge podge of products passes through a series of sorting devices, like the heavy-duty magnets that rotate around a belt and pull out the cans.
Or the optical sorter that reads the molecules of No. 1 and No. 2 plastics, separating PETE plastic from HDPE - two different chemical compounds.
One item that the equipment can't sort is the ubiquitous plastic bag.
"We have to manually remove them and they have to be sent through washing stations before being reprocessed," says RockTenn General Manager Jason Brown.
He says the best thing for people to do is to put the clean bags in the stores' recycling containers, where they are then recycled via a different, less energy-consuming process.
At the end of the last conveyor are neatly stacked bales of crushed product - clear soda and water bottles in one area, opaque milk and detergent bottles and butter tubs in another, tin cans, aluminum cans, corrugated cardboard and paper - all ready for transfer.
On the business end, more than a few companies benefit from recycling. RockTenn processes the paper into a variety of products to sell, much of it locally.
A Knoxville roofing manufacturer purchases some of the corrugated paper for use in certain materials. And Alcoa aluminum buys the cans.
Plastics and metals go to other plants in the Southeast, where they undergo the next steps, which may be grinding and melting.
Knoxville officials hope to add another 20,000 residents to the recycling program, depending on approved funding from city administration and City Council.
Interested city residents may visit www.cityofknoxville.org/householdrecycling or call 311 to get on a waiting list.