Using pulverizer attachments to simplify concrete processing

After working as the executive vice president and chief operating officer of Caterpillar’s construction machinery division in Pittsburgh for more than 30 years, Dave Trueman decided to venture off and start his own business in 2004.

That year, he founded Mamont Supply & Recycling, a company based in Mckees Rocks, Pennsylvania, that exclusively processes concrete from across the Pittsburgh metropolitan area. From sidewalk and road aggregates to entire concrete walls and oddly shaped slabs, Trueman and his staff of four process nearly 250,000 tons of material annually.

“We receive probably the bulk of any concrete refuse that’s developed within the confines of the city and the encircled metropolitan area, whether it be from the private sector or public sector,” Trueman says.

With nearly three decades of industry knowledge under his belt, Trueman conducted extensive research before opening his facility, keeping numerous factors in mind when weighing what type of processing equipment would be best for the company’s operations.

“Being an old equipment veteran, I researched the market through and through. It is a part of my due diligence to look and see what other people are using, how well the machines are performing, and how well the dealers and the factory supports the unit,” Trueman says.

Working with such a rugged material stream, Trueman says he was looking for equipment that would both withstand the damage concrete could cause and provide versatility to use in other applications. In addition to an impact crusher and a hydraulic breaker attachment, he settled on an excavator attachment that would provide him the flexibility he wanted: a MCP910-IT hydraulic pulverizer from Breaker Technology Inc. (BTI), a company owned by ASTEC Industries, which is based in Chattanooga, Tennessee.

“When we started, we recognized that we would preferably like to have a primary crusher, but we also felt that the need for an impact crusher first was most important to us. So, I felt the compromise in not starting with a primary crusher could be somewhat mitigated by using a hydraulic pulverizer,” Trueman says.

Trueman’s research has paid off—more than 15 years later, he’s still using the same excavator attachment he invested in to help get his business off the ground.

Incoming material

Concrete comes into Mamont’s yard primarily by truck and is segregated by size. Concrete already sized into digestible bits is kept separate from larger slabs of material. Meanwhile, what Trueman categorizes as the “ugly stuff,” like abnormally sized footers and other pieces of concrete, are placed in their own separate area of the yard.

Trueman and his team first use their BTI BXR65 hydraulic breaker attachment to size down any large pieces of concrete into bits small enough for the hydraulic pulverizer to tackle before it heads to the facility’s Eagle UltraMax 1400-OC crusher for final processing.

“The attachment is used mainly to further pulverize concrete before putting it into a crusher for additional processing. The process of pulverizing it also allows steel rebar to be released from concrete,” says Ray Szwec, BTI’s eastern regional manager, about BTI’s hydraulic pulverizer.

Before the concrete reaches the final screening area, it passes through a series of magnets to remove as much metal residue as possible. Trueman employs a 48-inch hydraulic magnet from Lockport, New York-based Moley Magnetics during the pulverizing process to remove much of the rebar. This makes easier work of removing the rest of it after crushing. After crushing the material, Trueman uses two oversized suspended electromagnets to lift the rest of the metal out of the concrete before screening.

“The pulverizer seems to be a very good first step for delaminating the rebar we receive,” Trueman says. “We were able to buy a hydraulically driven magnet that we have attached to a John Deere 200 [excavator]. We sweep the rebar initially off of our preprocessed material before we feed it into the crusher. Therefore, our crusher’s magnet system is more efficient because we’ve already eliminated all the rebar it would have to handle.”

Trueman says the combination of equipment, along with the pulverizer’s speed and versatility, has created a concrete processing strategy that has helped take his business to new heights.

“This has really been effective. I can tell you, [the pulverizer] has really stepped up our metal recovery efforts, it has measurably improved the quality of our end product, and it still provides us with the versatility to use on excavators for whatever needs we may have.”

Maintaining uptime

BTI’s MCP-IT pulverizers are compact, and their blades that cut rebar and their jaws and teeth that gnash the material are made of high-wear-resistant steel for durability.

Still, the attachment requires regular maintenance. The frequency of this maintenance depends primarily on how often the attachment is used and what it is used for. Szwec says teeth replacement tends to be the most common maintenance need, but staying on top of regular lubrication of its grease fittings and cleaning the machine when disconnecting its hoses is also important.

Trueman says the company has run the attachment nearly 40 hours a week since its inception. In that time, he says the pulverizer has required minimal maintenance beyond basic preventative services—a feat he credits, in part, to proper use of the attachment.

“Philosophically speaking, we never ask one of our pieces of equipment or attachments to do more than it’s supposed to do. That’s how we’ve extended the life of the equipment and minimized operating costs: fewer men, more attachments, more efficiency,” Trueman says.

Trueman also credits the design of the attachment itself for the minimal downtime required.

“These things are not only very reliable mechanically, but my older processor is really reflective of how good they are structurally. We’ve never had a massive structural failure at all in any of the components of the pulverizer,” Trueman says. “And I’m talking about a lot of material, a lot of really heavy-duty work [that it has been used for]. If we get a couple miles of highway slabs that are 10 inches thick, we can take one of those processors and sit those slabs up on their end and just go through them like Pacman.”

Going to the next level

After nearly 15 years of success with his two BTI attachments, Trueman finally made the decision last year to purchase one more of each.

He says that in addition to giving him more processing capacity, working with BTI has also given him “complete accessibility” to maintenance and parts whenever he may need them. He says the company has also come in handy with advice on what tools to use for particular jobs.

Trueman says he now deploys the second pulverizer to stay on top of incoming loads. He notes that concrete slabs sometimes come in “at an alarming rate,” requiring the capacity of both excavators. He adds that at the speed his crusher works, the second pulverizer helps to keep up with its quick processing rate.

Beyond the improved processing capacity, Trueman says the investment has allowed Mamont Supply & Recycling to generate more profits—a win-win for him and his company.

“Having the two processors really picks up the pace. We’re essentially in the scrap business, too, so when we have three layers of rebar, and it’s not thick enough to really use a hammer, we attack with the pulverizers and just make a little job out of a great big opportunity,” Trueman says.

This article originally appeared in the November/December issue of Construction & Demolition Recycling magazine. The author is the assistant editor for Construction & Demolition Recycling and can be reached at tcottom@gie.net.