There are a number of considerations that demolition contractors have to be mindful of when taking down a structure. Companies have to prioritize safe and environmentally responsible practices while maximizing efficiency and working to meet the owner’s various demands. But amid the detailed scope of work and rigorous planning that may be required for a given job, one thing that is always top of mind is profitability.

One of the ways companies can help guarantee a strong ROI for a project is by maximizing the metals recovered for recycling.

Drew Lammers, vice president of outside operations for Cohen Recycling, helps demolition contractors do just that.

Lammers, who works hand in hand with contractors to help them strategically plan their metal recycling initiatives in his role at the Middletown, Ohio-based scrap recycling company, is well-acquainted with the demolition side of the business.

Prior to joining Cohen, Lammers was the owner of Cincinnati-based King Wrecking Company. During this tenure, he also served as the National Demolition Association president and in other leadership positions at the association.

According to Lammers, one of the most effective things a contractor can do to derive metal value on the job is focusing on the nonferrous in a structure prior to teardown. While contractors use to try to pick this material during wrecking (and some still do), recovering nonferrous metals prior to the start of structural teardown work can help ensure material is not lost among other debris.

“If there’s an opportunity to go in and get your nonferrous out, or the majority of your nonferrous out before you start tearing a building down, you’ll get greater value because you tend to lose some of that material in your demolition debris after the fact since the majority of it is non-magnetic,” he says. “The dollars today are in nonferrous metals, which are seeing near record highs in terms of value. I think sometimes some demolition contractors are so worried about getting the iron and have the mentality of ‘get the steel, get the steel, get the steel,’ they forget that copper or aluminum or stainless is worth a lot more when it comes to a per pound basis than the steel is.”

Lammers says that even though there might be significantly more ferrous material on a project by volume, the nonferrous can add up to big value due to today’s prices. Additionally, ferrous material is relatively easy to pick from a project since it can be grabbed by a magnet after teardown.

Lammers says common sources of scrap that contractors can identify include items such as aluminum siding, rebar, electrical wire, duct work and HVAC components, structural beams, light fixtures, plumbing, gutters, shutters, railings and overhead doors.

Getting these materials out of a building is the first step, but processing them effectively brings a whole new set of challenges. While processing can often be cumbersome and time-consuming, Lammers says that the work that goes into preparing the material has a direct correlation to the value that can be gleaned from it.

“If you’ve copper wire in today’s market, for example, it might be worth putting it through a stripper to get down to the bare copper because it’s worth more than an insulated wire. Now, there’s labor involved to do that, but contractors have to determine what’s worth it in terms of the ROI,” he says.

Lammers says that even if there are higher value metals in a load, if they’re mixed in with less valuable material, the contractor won’t be able to get as much for it as if it was properly separated. Similarly, if a load is mixed with contamination like concrete, dirt or garbage, value will be reduced since the scrap recycler will have to pay to have that landfilled.

“Contractors want to get in and get out as quick as they can on a job because time is money, but separating the metals is almost as important as getting that material in the first place,” Lammers says. “When it comes to us as a scrap recycler, we will grade it as if it’s mixed iron or if it’s a shred package, etc., and pay accordingly.”

Lammers says proper sizing of the material is also crucial. Typically, the larger pieces of metal that come from demolition jobs are not mill ready and need to be cut.

That’s where excavator shears come in. Contractors who use shears to effectively size the material can reduce the number of hands the material has to touch to size it for the mill, which helps save money. Additionally, proper sizing allows contractors to fit more material into a container or trailer, which translates to fewer trucks leaving the site.

“It’s already hard enough to find enough truck drivers to get material off-site. So, the fewer truck loads you have, the less it’s going to cost you and the quicker you’ll be able to ship the material,” Lammers says.

He notes that a handful of the biggest contractors can save even more by going “mill direct” with their material due to their ability to properly size and process on-site; however, the overwhelming majority of companies don’t have the resources, time or expertise to handle this on their own.

While a big pocketbook helps, it doesn’t take the resources of the industry’s largest demolition companies to effectively recycle metals, Lammers notes.

“When it comes to getting the most value for your metal, it starts with management. It boils down to the question, ‘Does management want to do this?’” he says.

Lammers says that demolition companies interested in generating the highest value from their materials should think about consulting with a knowledgeable scrap recycler.

“In my experience, scrap recyclers are more than willing to come out and help these contractors,” Lammers says. “At Cohen, we do it all the time. We’ll go on-site, check out a job and say, ‘If you guys do X, Y and Z, this is how much more money you’re going to get, but if you just throw it all in a dumpster together and give it to us in one big mix, you’re going to get less because we have to do all that separating and processing.’”

Lammers says that although scrap recyclers will pay less for materials that aren’t properly separated or processed, most scrap recyclers ideally want the material sorted and cut for a quick turnaround because of the market risk that comes from sitting on significant tonnage.

He says that Cohen, and an increasing number of scrap recyclers, offer to place shears and operators on the ground for a cost to do all the cutting, sizing and shipping to the mill themselves. This allows contractors who don’t have the resources, time or desire to process metals to focus on demolition rather than preparing metal for recycling. Lammers says that by contracting with a scrap recycler for these on-site services, if there are any rejections from the mill, the recycler bears the responsibility, not the contractor.

Beyond helping process materials, Lammers says that bringing a scrap recycler on-site to “offer a second set of eyes” on a project can help demolition professionals identify areas for opportunity.

“We’ll go out on jobs when contractors are bidding them and we’ll help them determine how much tonnage is in there. I won’t tell the contractor how to do the job, but I’ll let them know that if they take certain steps, what the maximum value of their scrap could be,” Lammers says.

By consulting with a scrap company prior to and during the demolition phases of a job, Lammers says that contractors can ensure they’re on the same page when it comes to assessing value.

“My big thing is, just reach out and ask. Ask the scrap company about the different metals on-site and what they might mean in terms of value,” Lammers says. “The larger scrap companies should be able to say, ‘This is P&S, this is heavy melt; this is rebar, this is shred; this is clean sheet, this is unclean sheet—there are all these different varieties and they’re all worth something different.

“When you’re having these conversations up front, it helps. If you’re talking about separating materials to maximize value, for instance, and the contractor thinks they have one type of material but the scrap company is classifying it as another, the scrap company can go back to them and say, ‘Here are the pictures of the material. Do you remember what we discussed in terms of how we need it cut? Let’s get with your operators and explain to them how we need the material sized.’ We do that all the time and that just comes down to having open lines of communication.”

While Lammers says that contractors all have similar methodologies when it comes to extracting metal from a structure, ensuring a high recycling rate often comes down to embracing a simple philosophy.

“Just know what you have and try to get it,” he says.

The author is the editor of Construction & Demolition Recycling magazine and can be reached at aredling@gie.net.

GreenRock Recycling LLC, Clinton, New Jersey, is a construction and demolition recycling company serving residential, municipal and commercial customers throughout the state.

The company, which is a division of the Brian Plushanski Construction Company, started out in 2012 offering standard and dyed mulch, topsoil, mason sand and screenings.

However, sensing an opportunity, the company invested in a Kleeman Mobirex MR 110 ZSi EVO2 impact crusher, manufactured by the Wirtgen Group, in late 2016 to help it process stone and aggregates.

Thanks to its investment, the company has been able to produce a New Jersey Department of Transportation-certified recycled concrete aggregate (RCA) and processed reclaimed asphalt pavement (RAP) product that has a robust market with contractors in the Garden State, the company says.

“Our Kleemann crusher makes a very nice, clean RCA that compacts well, looks like 1 1/2-inch-minus dense graded aggregate, yet is less than half the price,” Mike Plushanski, general manager of GreenRock Recycling, says. “And our RAP is used mostly as a base material, which also is highly compactable and affordable.”

Plushanski explains that the crusher was pivotal in helping the company evolve from its initial emphasis on wood processing.

“Our permitted recycling [operation was] initially wood—as in tree parts only, including stumps, wood chips and logs,” Plushanski says. “But now we receive brick, blocks and concrete, which we commingle to make recycled concrete aggregate. And we receive clean asphalt to make RAP. We balance the cost of processing by charging tipping fees in addition to the product sales.”

In addition to recycling, GreenRock has a small shale quarry on its property in Clinton, which it rips to produce certified clean fill.

“We’re just trying to bring our site down to road grade, so we have one nice level property. The shale can be used very much the same way as RAP, except that shale has more uses, as New Jersey is very strict on how RAP is used. But as a certified clean fill, shale can be used anywhere,” Plushanski explains.

Finding a replacement

GreenRock’s Kleemann crusher replaced a small 1,000-ton per day jaw crusher, which was inherited from an existing construction business, that the company originally used to crush incoming material.

“[We were growing] like crazy, and that little crusher was going 40 hours a week and not putting a dent in the stockpiles,” Plushanski says. “Concrete was coming in so fast that the piles grew even as we were crushing. It also did not have a screening system, and that was part of the problem; we weren’t able to sell material, as flat ‘pancake’ pieces larger than 2 inches would just drop through the jaw. We were unable to meet size specs, and we could not get DOT certification for 1 1/2-inch material, which a lot of contractors need for big jobs. We needed a higher capacity crusher, and we needed to meet DOT standards, so the Kleemann impact crusher was the way to go.”

According to Plushanski, Kleemann’s touch screen control system was one asset of the machine that sold GreenRock on the MR 110 Z Si EVO2.

“The Kleemann is so much more advanced than the other machine we were using,” he said. “With its remote control, I can adjust everything, including the distance of the curtains off the blow bars, or open up the return conveyor. If something goes wrong, you can shut down faster and diagnose the problem and correct it. With the other machine, you had to walk up to a difficult-to-navigate computer screen. With the Kleemann, you just touch the part of the machine on the screen. It’s user-friendly.”

Another aspect of the Kleeman crusher Plushanski liked was how its diesel-electric drive system helped the company manage costs. “Our old jaw crusher was burning 11 gallons per hour,” Plushanski says. “We demoed [another crusher that] was upwards of 14 gallons an hour. The Kleemann burns 6.5 gallons an hour, with a 500-horsepower motor running. The fuel savings are huge.”

The independent prescreen functionality of the Mobirex hopper also was a plus for GreenRock since the company leaves all the fines in its mix. Allowing the fines to bypass the crusher increases wear part longevity, Plushanski says.

“The prescreen [that is situated] ahead of the impactor is so much more efficient than the simple [hole design] of the other machine we looked at,” he says. “Now, being able to adjust the speed of it and making sure we were dropping all the fines out, we don’t have an ounce of fines more than should be going through the rotor. They are dropping right down to the main conveyor and out to the 1 1/2-inch screening system, and not beating up our blow bars.”

Alternatively, GreenRock processes RAP to 1 1/4-inch-minus size, and it’s often used as parking lot or driveway base material. For RCA and RAP, fines are retained to create a product similar to a dense graded aggregate, Plushanski says.

“We want a compactable base material, and for now, we choose not to remove fines out the side conveyor off the prescreen,” he explains.

All about savings

Plushanski says that starting up the crusher in the morning has been made easier thanks to its automated capabilities, especially its automatic closed-side gap setting adjustment.

“You can do the zero-point adjustment all electronically,” Plushanski says. “Whatever size I set the curtain from the blow bars, I know it’s accurate. We no longer crush 40 hours a week as we did with our old crusher. Instead, we only need to crush one or two days a week, so every couple of days, when [we start for the day], I will check the bars and set a new zero point.”

The fact that so much of the Kleemann machine is computer-controlled is a benefit to GreenRock, Plushanski notes.

“The computer operation is a major purchase point,” he says. “The other crusher we demoed had all mechanical adjustments. With the Kleemann, one morning when I was firing it up, I realized I was still set up for RAP. I changed the curtain distance as we idled up for concrete. I changed the prescreen vibrating and hopper speed. I was able to do all three adjustments from the touch screen on the machine, whereas with the other crusher, this meant having to shut down and climb up the machine with a wrench. I would have been up there a half hour trying to dial it down.”

“With the Mobirex, it takes me 30 seconds to adjust three parts of the machine versus not being able to adjust the three parts all at once with the other machine,” he added. “You couldn’t do the prescreen adjustment [with the other machine], and to just do the hopper and blow bar adjustment would have taken me a half hour with the machine off. With the Kleemann, we are up and running without having to stop.”

Kleemann’s diesel-electric drive system also helps the company save time at start-up, especially on cold days.

“It’s nice not having to wait for the hydraulics to warm up,” Plushanski says. “It’s freezing cold up here half the year. In the mornings, we don’t have to wait 25 minutes for the hydraulics to warm up. With the old crusher, we’d start it up, run a conveyor and go back to the office to finish our coffee while it warmed up. When we demoed the Kleeman crusher … it was 9 degrees outside, and it was up and running in 15 minutes.”

Another time-saver for the company is made possible by the machine’s ability to be set up and dismantled seamlessly. “It’s easy to set up and take apart,” Plushanski says. “The conveyor-mount secondary screen system unplugs with quick disconnects. In 15 to 20 minutes, I can drop it, change all the screens and put it back up, and recycle a different product.”

Plushanski says the mobility of the machine also helps the company save time. Since GreenRock moves the impactor to different stockpiles as it produces different products, the ability to change screens quickly and move from pile to pile is a major asset for the company.

Besides time savings during setup, the machine’s design also allows GreenRock to spend less time on upkeep and maintenance.

Aluminum shields around the crusher’s magnet keep the scrap steel and iron discharge, such as from nails or wire, from jamming up the equipment.

“Nothing builds up because it can’t stick to the aluminum, but our old crusher would have had thousands of nails stuck to the frame where it had become magnetized. It was difficult to clean every day,” Plushanski says.

Scrapers on the belts are another advantage from a maintenance and cleanup perspective, Plushanski says.

“It’s the little things that make a difference, like scrapers at the tops of each of the conveyors,” he notes. “No adjustment is needed for them, and they get all of the material off of the belts. As a result, I don’t have a 2-foot-high mound of dust under the machine that I have to clean up each day.

Further, a steel pan feeder located under the crusher intercepts crushed material in advance of the conveyor, absorbing the shock and protecting the conveyor. This saves the company from having to replace belts.

“We use to pierce belts like there was no tomorrow on our old jaw,” he says. “We’d spend $10,000 a year on belts that we otherwise would have no problem with. But these belts never get that abrasive impact. And side rubber skirts keep the material trimmed and centered, and that keeps dust out of the machine.”

In addition to Kleemann staff, product support is provided by GreenRock’s distributor, Komatsu Northeast, which makes ensuring uptime easier for the company.

“I usually call … our Kleemann technical representative when I have a question, and he’s always there for me,” Plushanski says. “But our family has dealt with our distributor for 30 years, and they are awesome. If we need a visit on-site, they are here in two hours.”

Whether it is the ability to market new products, increase efficiency on the job or save money due to more intuitive design, the Kleeman product has been a rock-solid investment for GreenRock Recycling as it continues to grow its operations.

Matthew Graves is the director of marketing communications for Wirtgen America Inc. He can be reached at matt.graves@wirtgen-group.com.

Converting fines and less desirable fractions of the wood stream into marketable products is an ongoing challenge for C&D recyclers. However, new research from the University of Florida shows the potential benefits of using biochar and biochar-blended fines in landfill applications to neutralize both odorous hydrogen sulfide (H2S) and hazardous per- and polyfluoroalkyl substances (PFAS).

Timothy Townsend, professor at the University of Florida’s Department of Environmental Engineering Sciences, gave a presentation titled, “Opportunities with C&D Fines and Wood-Derived Biochar” on March 22 at the Construction & Demolition Recycling Association’s (CDRA’s) C&D World convention.

Townsend, whose research focuses on identifying beneficial uses for waste materials, has partnered with the CDRA to identify opportunities for C&D wood and fines.

C&D wood is typically derived from dimensional lumber, pallets, land clearing material, and engineered and treated wood. Townsend says that dimensional lumber, or what recyclers may refer to as A-line wood, often can be sold to those creating landscaping products or other materials without much difficulty. Engineered and treated wood, however, can present more of a challenge due to the potential presence of glues, paints and chemicals.

Fines, which are the shake-like byproduct of screening and sorting processes, are commonly composed of a variety of materials. Common markets for fines include use as landfill cover, fill material, and as soil and agricultural amendments. However, similar to some C&D wood, fines can be difficult to market since the composition and quality varies based on a recycler’s waste stream and screening and sorting processes.

“If you’re looking to market fines as landfill cover, and you have gypsum in the fines composition, you can have hydrogen sulfide that’s produced that limits the places around the country where this material can be used,” Townsend says.

“In terms of using fines as fill material, I’ve spent a lot of time working with CDRA members trying to figure out if there was a way to make those fines a better product,” he continues. “I would encourage recyclers to explore opportunities to process and create better products. I think, on the horizon, you’ll have opportunities to create fines that would be a stronger material that might be suitable for some type of base course or some more structural material, or even material that is better suited for agriculture. But the big challenge if you want to go use fines out in the environment, like all waste products, there can be small amounts of chemicals, such as arsenic, lead and sulfate, that can be a concern.”

Because of these environmental issues, Townsend says recyclers can run into problems when trying to market fines “as is” but, “if recyclers recognize what the concerns are potentially, they can create a better product” through investments in new technologies. He says that this requires recyclers to shift their mindsets from “managing byproducts to developing products.”

Townsend says that air separation, screening and washing processes can be especially useful in separating aggregate, wood, paper, plastic and drywall concentrations in the fines. By better sorting this material, recyclers can market fines in a way that may help overcome regulatory challenges.

Once recyclers fully understand what the composition of their fines is, they can make strategic decisions and investments to fine-tune this mix to appeal to different end markets.

By being more selective on the waste that is processed, the size fractions that are generated, and by embracing washing and blending solutions, operators can overcome some limitations that often exist when looking for markets for C&D fines, Townsend notes.

Benefits of biochar

Townsend says that recyclers have begun to explore converting less marketable wood from their B and C lines into biochar. Biochar, which is a charcoal produced from the pyrolysis of wood in a low oxygen environment, can be used on its own or mixed with fines in landfill cover applications to mitigate H2S generation that naturally occurs at landfills and in some gypsum-containing fines.

Townsend says his research has shown that the more biochar you add to fines, the more H2S you sequester. However, he concedes that having a mix of 90 percent biochar to 10 percent fines, for example, defeats the purpose of trying to find an economical use for fines.

He says that a mix with 15 percent biochar reduces H2S by one to two orders of magnitude in lab testing. At 30 percent biochar, H2S is reduced by two to three orders of magnitude or more. The sweet spot for both economical and effective use probably lies in biochar blends of 10 to 20 percent, he says.

Townsend says that because moisture content can exacerbate H2S generation in drywall-containing fines, fines used as cover material in wet climates can have the propensity to generate more hydrogen sulfide than in drier locales.

In initial field tests where fines were used as alternative daily cover at landfills, Townsend says that measurable H2S concentrations were periodically detected, although at low levels. However, when the fines were blended with biochar, H2S levels were uniformly below detection in the field tests. Townsend conceded that these studies, which were delayed due to COVID-related shutdowns at the university, were still ongoing.

A word on PFAS

In addition to mitigating H2S generation at landfills, Townsend says biochar shows promise for capturing PFAS chemicals. These chemicals have been subject to scrutiny from the EPA and other regulators in recent years due to their health-related risks that include liver damage, thyroid disease, and cancer, among other issues.

“For the C&D recycling industry, PFAS is not going to be as big of a deal as [lead-based paint or asbestos], but the idea is that it is better to become educated now and then be able to think a little bit on how the industry can position itself with some of its markets to perhaps be able to address the issue,” Townsend says.

Townsend says that these PFAS “forever” chemicals, which are used to make an assortment of commercial and consumer products such as nonstick cookwear, water-resistant clothing, stain-resistant fabric and carpet, and packaging and firefighting foam, are found in leachate at every landfill in the world.

“If you look at C&D landfills, you find PFAS in the leachate—it’s not that different than regular MSW landfills. … In terms of bulkier C&D-type items where you might see PFAS are mattresses, furniture, clothing, tents, umbrellas, carpet and carpet padding. The good news is that with concrete, drywall, wood, most of the products C&D recyclers deal with, overall PFAS concentrations should be pretty low,” he says.

Townsend says that even though PFAS isn’t found in quite the same concentrations as in MSW streams, the EPA’s emphasis on identifying and mitigating the substance requires C&D recyclers to be at least aware of sources of contamination.

Townsend singles out carpet, fines and asphalt shingles as primary sources of PFAS that C&D generators should be mindful of.

In discussing how PFAS could influence shingle recycling markets, Townsend says that recycled shingles in hot mix asphalt concentrations likely wouldn’t lead to an issue, whereas ground shingles used in road pavement could raise the issue of environmental contamination due to its potential to leach into the groundwater.

Despite the environmental concerns with PFAS, Townsend says there are some potential opportunities for recyclers.

“With biochar, we know it can help [sequester] H2S, but can it take up PFAS? Absolutely it can, because a lot of the PFAS remediation sites across the country use activated carbon [that is similar to biochar] to remove that,” he says.

During his presentation, Townsend shared lab results that showed how biochar mixed with fines helped greatly neutralize PFAS concentrations found in test samples. According to University of Florida tests, the inclusion of biochar in a sample equated to a greater than 80 percent reduction in PFAS found in leachate.

“Just like with using biochar to neutralize H2S, C&D recyclers would have to be investing in technologies and equipment to make the biochar from a fraction of their wood stream [for PFAS mitigation], but then there could be the ability to market that as a product,” Townsend says.

“Landfills need soil products. [MSW landfills] need this because it is part of Subtitle D. And in a lot of cases, they need to pay to get soil in because they don’t always have big borrow pits,” he says. “So, imagine that the soils that recyclers could provide to them would be such that they could help control the H2S problem, but also help absorb and trap material like PFAS. … If you integrated some of these fines with biochar or just used the biochar itself from C&D-derived sources … you have the ability to bind these chemicals up. This might have more applicability in some markets than others, but for C&D recyclers, it is something to think about. C&D-derived biochar continues to show a lot of promise.”

The author is the editor of Construction & Demolition Recycling magazine and can be reached at aredling@gie.net.

The slowdown in the commercial building, demolition and C&D recycling sectors brought about by COVID-19 shutdowns and related pullback on investments had many industry participants wary of an uncertain future at the start of the year.

In addition to mass vaccination availability, a sweeping infrastructure plan was the thing many professionals cited as having the potential for counteracting the lingering aftereffects of the pandemic.

Such a plan took shape when President Biden released his administration’s $2 trillion infrastructure initiative in March.

The plan proposes to modernize 20,000 miles of highways, roads and main streets; fix the 10 most economically significant bridges in the country in need of reconstruction; repair the worst 10,000 smaller bridges; replace thousands of buses and rail cars; repair hundreds of stations; renew airports; and expand transit and rail into new communities.

The plan also commits to build, preserve and retrofit more than two million homes and commercial buildings; modernize schools and childcare facilities; upgrade veterans’ hospitals and federal buildings; and eliminate all lead pipes and service lines in the country’s drinking water systems.

Biden, who calls the plan “the single-largest investment in American jobs since World War II,” forecasts that the proposal could help create jobs for millions of Americans. Despite the prospects for industry professionals, the president faces significant political opposition in passing the bill in its current iteration.

Republicans have generally called out the plan for being too costly, having too many elements nonessential to infrastructure included, and relying on increases to corporate taxes as a key funding mechanism as reasons for their opposition.

In an effort to garner across-the-aisle support, Biden has made it clear he is willing to work with Republicans to find common ground.

“I’m prepared to negotiate as to the extent of my infrastructure project, as well as how we pay for it,” Biden has said.

Republicans have countered with infrastructure proposals a quarter to a third of the size the one President Biden initially unveiled.

Though Democrats could conceivably work to pass infrastructure legislation independently through a process known as budget reconciliation, Biden has continued to meet with both sides of Congress to try to build consensus for passage of the bill. While talks are ongoing, the political jockeying could carry on for months as both parties negotiate the scope of the bill.

With the construction, demolition and recycling sector eager to get back to pre-COVID business, the industry will be keeping a close eye on negotiations. With its passage, an infrastructure plan could be a spark that helps lay the groundwork for long-term stability that seemed so elusive just a few months ago.