Visual Aid

C&D recycling facilities use many methods to separate materials by type and size. Picking lines are useful at either removing contaminants or larger pieces of debris, and screening further separates fines from midsize material. The smaller the material gets, the harder it can be to effectively hand sort.

Baumann’s Recycling Center opened in Cleveland in 2011. At the time, manual sorting stations were used at various stages of the material recovery process.

According to Bill Baumann, president of parent company, Baumann Enterprises, manual sorting was only capturing about 30 percent of the recyclable wood. This wasn’t good enough for Baumann, who says he tries to send as little to the landfill as possible.

In January, Baumann’s Recycling Center installed an optical sorter to help improve wood recovery rates. As material zips by on a high-speed belt, the optical sorter uses infrared technology to read different material types. Because wood has its own signature, it is detected from the stream.

While the rest of the material stays on the belt, the wood is ejected from the stream. It falls onto a separate belt, which creates a clean pile of wood. The wood is prepped for sale as either mulch or boiler fuel, depending on the time of year.

Baumann says the optical sorter has led to a big boost in production. “It is a huge difference,” he says. “I am getting at least 85 percent of the wood out of the material.”

Jeremie Bourgeois, project manager of Sherbrooke OEM, Sherbrooke, Quebec, says Baumann’s has always been effective at screening overs and unders.
 

“However, when we looked at the midfraction, we felt that lots of wood and aggregates could still be reclaimed, so we simply added a destoner right after the magnet to take all of the aggregates out. Then we put the optical sorter after the destoner to sort the wood out.” Bourgeois adds, “The optical sorters can pick all these small wood pieces that human’s simply can’t pick.”

When Baumann’s first started operating the optical sorter, some of the older, decomposing wood caused some issues in the sorter’s ability to read the material.

“Fortunately, our engineers modified the program and, after a few tweaks here and there, were able to differentiate a true piece of wood from a contaminant covered with some decomposed wood,” says Bourgeois.

Once the initial kinks were worked out, Baumann says he noticed a difference right away in the amount of wood being recovered and the amount of labor being saved.

Instead of having seven or eight people sorting out wood, Baumann has one person quality checking the line. The destoner separates the smaller pieces of aggregate and blows the light fraction, consisting of mostly papers, off of the line, which is monitored by a single operator.

“The efficiency was the driver and being able to reduce labor,” Baumann says about why he made the investment in the new equipment. He estimates labor savings alone to be more than $140,000 per year.

Additional savings come from disposing of less material. More wood recovery also means more product and more profit.

“Whatever I don’t recycle, I have to dispose of, which obviously is a cost. My whole driver is to be able to be as efficient as I possibly can be with the products I produce,” says Baumann.
 

The author is managing editor of Construction & Demolition Recycling and can be reached at ksmith@gie.net.

A video showing how material is processed at Baumann’s Recycling Center is available at www.CDRecycler.com/baumanns-recycling-process-video.aspx.