Megan Workman

The author is associate editor of Recycling Today magazine.


Equipment focus: Morphing for markets

Equipment News

As new end markets develop for wood, Dem-Con Cos., Shakopee, Minnesota, has added equipment to cater to customers and stay ahead.

July 9, 2015

Equipment not only helps to ensure daily tasks are completed, the type of machines on-site also dictate what type of work can be achieved each day. The more limited an operation’s equipment, the fewer the end markets available for the finished products produced.

Jason Haus, CEO and co-owner of Dem-Con Cos., Shakopee, Minnesota, says he realized how limited his recycling firm was when it came to processing wood. With a goal to sell material to the highest potential end markets, Haus says Dem-Con had to add more equipment to serve these profitable markets.

Dem-Con has been serving the Twin Cities and greater Minnesota for nearly 50 years, and today operates a construction and demolition (C&D) material recovery facility (MRF), a single-stream MRF, a shingle processing yard, a wood processing facility and a landfill.

Efficiently equipped

The company has been grinding C&D wood since 1999. At that time, Dem-Con workers would dump debris on the floor and sort through the wood.

However, the company learned that the more often material is handled by hand, the less valuable it is, Haus notes. “The more times you touch the wood, the more it costs you; if you can have direct delivery to grinders, you can sell it at an economically viable price.”

To lessen the “double handling” of wood, Haus says, Dem-Con upgraded its C&D processing system to continue to batch feed wood and also to direct material to an under conveyor. Equipped with a Rotochopper EC266, the electric horizontal grinder can now better handle the increased C&D wood coming in Dem-Con’s doors, Haus says.

Workers have the ability to batch feed using a Caterpillar 950 loader or directly feed wood from its C&D sort system. He explains that the batch feeding opportunity is ideal for handling direct loads of wood that are clean and do not travel through the entire system.

From the horizontal grinder, located perpendicular to the C&D MRF system, the next option is to either send material through a hammermill system, which Dem-Con acquired one year ago, for additional size reduction, or to direct load trailers with the appropriate screen size via a conveyor.

“We have the ability to direct the load trucks right off the grinder, or we flip a switch on the conveyors and they deliver it to a hammermill that makes it 1/8-inch-minus in size,” Haus says.

Smaller material is pneumatically blown from the hammermill into a trailer using an air handling system while augers are used to place remaining materials into a trailer.

Haus says, “We have the option to go either way depending on the material we’re handling. We can switch back and forth within minutes so it’s nice to have that flexibility.”

With two sets of augers, installed four years ago, workers can load trucks all day long, he says.

He points out that Dem-Con’s large dust collection system has helped the company to completely eliminate dust from its operations.

“The wood that’s incorporated in mixed C&D has a lot of dust in it in general; our bag house system actually cleans the dust off the wood and cleans the material up,” he says.

More markets

The 2008 upgrade came about as the company saw more throughput at its operations. Haus says the expansion helped prevent Dem-Con from being “beholden to any one market.”

He explains, “The market drove us to making sure we have multiple end markets. When all you have is a grinder and nothing else, you’re kind of limited on what markets you can serve and what sizes of material you can produce.”

Haus continues, “As markets continue to develop, we just keep putting in more equipment to service them. It’s morphed quite a bit,” he says of Dem-Con’s processing system.

As wood makes up the highest percentage of material Dem-Con recovers, Haus says the company made sure it was protected on the end-market side by catering to its customers.

End market customers want consistency in all aspects of the job, from delivery schedule and moisture content to quality, he says. “For us to do that we had to look at the right equipment for us so that we could provide that consistency to our customers,” Haus says.

When Dem-Con entered the wood recycling sector 16 years ago, landscape mulch was the only marketplace in which the company sold material.

Today, Haus refers to that end market as one with low value. “We try not to sell to markets we had in 1999 as the end markets have developed and we’ve helped to diversify where we send material to. Adding equipment helps us to manufacture a product that each of our different end markets wants. It’s not a one-size-fits-all market,” Haus notes.

Dem-Con produces a 2-inch-minus material for its landscape mulch, now it lowest-grade market. This market does not have many quality specifications, describes Haus, other than ensuring the wood is cleaned, untreated lumber and low in moisture content.

On the opposite end of the spectrum, the company produces a product for biomass plants, which must be very clean (no stain or paint) and ranges in sizes from 2-inch-minus to 1/8-inch-minus, Haus says. “There is high quality control there; it’s the highest value and highest value-added material we have,” he says.

While moisture is not a factor in the clean material the company sends for erosion control applications, moisture is important in wood that is to be used as animal bedding, according to Haus.

Controlling moisture is another daily concern, yet Haus says Dem-Con has this under control. “For us to be able to keep material dry is a big thing. That’s what our loading building does. It takes material the trucks load in so [wood] is not sitting in a large stockpile somewhere,” Haus says.

Haus addresses the risk of relying on one end market and the value of expanding markets served when he says, “Only having one outlet is always a risk, and we want to try to mitigate those risks as much as we can. Finding more homes for those materials is the best option.”

Case for closed loop

The next phase of C&D recycling, Haus predicts, will entail wood manufacturers taking back material in a type of closed-loop system. While he doesn’t know when this change will occur, he does acknowledge that it is a slow-moving process.

“The next phase I would like to see are different types of manufacturers of lumber taking wood materials back and making a composite out of the material that is being recovered,” Haus says.

Dem-Con has worked with manufacturers to take back wood or incorporate used C&D wood into their projects. “If we want to raise the bar of a higher standard of usability with these products, I’d like to see it head there,” Haus says.

As for equipment used to accomplish this goal, Haus says he sees more mixed C&D recycling facility operators adding grinding systems to their operations. The grinders today have gotten better at reducing daily and monthly maintenance costs with improved teeth, rotors and overall are more structurally sound, he describes. More operations today are using electric units that are stationary, he says.

“Rewind to 2009 and there were very little electric units being sold, but a lot now are electric units,” Haus recalls, adding, “I absolutely think more and more grinders will be added to C&D systems, and more systems like ours, where it’s automatically fed from the sort line, will be added.”



The author is associate editor of Construction & Demolition Recycling and can be reached at


Current Issue

Follow us on Twitter
Follow us on LinkedIn