Equipment Focus: Portable Shredders

July/August 2014

Large, portable hammermill and shear shredders are more affordable and flexible than stationary shredders, giving recyclers more options for entering the shredding market.

By Deirdre Bannon

Hammermill and rotary shear shredders are not new. What is relatively new, however, is portability for shredders large and durable enough to handle heavier steel products—including, for some, car bodies and engine blocks. Although these machines sell for a fraction of the cost of a stationary hammermill shredder, they’re still a significant investment and require consideration of logistics, environmental controls, and the nature of the potential scrap supply. This overview of portable shredder costs, benefits, and capabilities can help you decide whether a portable shredder is a smart choice for your operations.

Two Approaches

Equipment manufacturers have come at this market from two different angles. Some have adapted hammermill shredders, turning them into either modular designs that allow easy assembly and disassembly for moving or into self-contained, tracked or trailer-mounted machines that move under their own power. At the same time, manufacturers of slow-speed, high-torque shredders have created larger, more powerful machines, also either tracked or movable via trailer, some of which are durable enough, they say, to handle a regular supply of automobiles.

Hammermill shredders. Portable hammermill shredders closely mimic their stationary predecessors, with swinging hammers inside an enclosed box that pulverize the material being processed. These heavy-duty, diesel-powered machines can weigh more than 150 tons, so making them portable is a challenge.

The Shredder Co. (Canutillo, Texas) designed its Little Rascal line of portable hammermill shredders to create a heavy-duty shred on par with that of a stationary shredder in a machine that’s as light as possible and can achieve the lowest cost per ton for operation, says Scott Newell, chairman and CEO. The machines, which have built-in dust-control systems, can shred just about anything a stationary machine can, including vehicle bodies and engine blocks, he says. Throughput capacity ranges from 10 tons an hour for a 500-hp machine to 30 tons an hour for a 1,500-hp machine. For moving, the shredder separates into four pieces and detaches from its steel legs. A crane can lift the four pieces and the legs onto four tractor-trailer beds. Users can disassemble it in one day and reassemble it in two to three days, Newell says.

Mobile hammermill shredders from Zato (Prevalle, Italy), which range from 1,000 to 3,000 hp, can produce up to 40 tons of shred an hour. In addition to shredding various types of metals, the Blue Shark line can shred vehicle bodies and engine blocks, producing a dense end product that can weigh 65 to 75 pounds per cubic foot, the company says. The system—which includes a rejection door, a magnetic drum separation system, and dust and fluid collection systems—fits on two mobile four-axle trailers and includes the drive assembly and engine.

ZB Group (Gipuzoka, Spain) says it offers the first track-mounted, portable hammermill shredder line, the Thor, with shredders that can start operating the day they’re delivered. Models range from 440 hp to 2,000 hp, processing up to 25 tons an hour into shred that weighs 80 pounds per cubic foot. The 440-hp machine is designed for lighter nonferrous metals; the larger machines are designed to process a steady diet of vehicle bodies and engine blocks, says Bill Padula, vice president of Peninsula Equipment (West Columbia, S.C.), the North American distributor for ZB Group. Some Thor models also have dust-collection systems, he adds.

Shear shredders. Manufacturers of slow-speed, high-torque shredders that tear or cut material say such machines can handle some heavier material such as vehicle bodies, but not a constant flow of it. Each manufacturer’s equipment has different capabilities and limitations, making it essential to select carefully based on the potential scrap supply. These lighter machines, which have either diesel engines or electric motors, are either track-mounted or have an integrated flatbed trailer.

Granutech-Saturn Systems (Grand Prairie, Texas) manufactures a portable twin-shaft shredder line designed to process light-gauge steel items like appliances and nonferrous material. The shredder can process a vehicle or engine block, although a round, solid shaft like a crankshaft could damage it, says Mike Hinsey, international vice president of sales. Horsepower ranges from 150 to 400, and the shredders produce output weighing about 20 to 30 pounds a cubic foot. Users can assemble and disassemble the shredder in about one hour, he says. The shredder is mounted on a flatbed trailer.

The synchronized, two-shaft design of the portable shredders from Hammel New York (Bohemia, N.Y.) tears and rips material with hooks and knives that move in and out, interacting with the processed material, says Ralf Semler, regional sales manager Southeast. The shredders can handle car bodies, engine blocks, and transmissions as well as appliances, aluminum, and iron, he says. Horsepower ranges from 350 to 1,500, and the capacity ranges from 6 to 60 tons of material an hour. The machines are powered by diesel engines, but the company also can build them to use electric power. Similarly, Hammel’s portable shredders come with crawler tracks, but the company also can affix some models to semi-mobile hook-lift/roll-off frames, Semler says.

Zato’s Blue Devil line, a mobile shear shredder system, can shred 25 to 30 tons of ferrous an hour with horsepower that starts at 700. The shears’ dual-shaft hydraulic drives work independently of one another to maximize performance and shred quality, says Sean Abenstein, sales manager and equipment consultant for Gensco Equipment (Toronto), Zato’s North American distributor. The shredder can be mounted on a flatbed trailer, requiring only a tractor to move it to a new location.

Moving Features

Manufacturers and sellers of mobile hammermill and shear shredders tout the machines’ many benefits, one of the biggest of which is the mobility. You can “take the machine to the material rather than waiting for the material to come to you, which can be a big advantage for recyclers with multiple collection yards,” Peninsula Equipment’s Padula says.

When a company can “process at one yard this week and another yard the following week or month, the uptime can be much higher with one portable machine versus having multiple stationary shredders that could be down for extended times,” Granutech’s Hinsey says. “You can really become a processor for hire—just as you would with a portable car crusher—and provide a service [for] a yard that doesn’t have a shredder.”

Also, with industry consolidation, Hinsey says, “it’s common for a processor to have half a dozen or a dozen or more yards, maybe in multiple states, and each yard doesn’t necessarily need a shredder.” Instead, the company could have “one or two portable shredders and put those at the yards where they’re most needed at a given time.”

Portable shredders’ smaller capacity and lower operating costs also are valued today, when there seems to be less scrap available. For a long time, many recyclers wanted the biggest, most powerful, highest-capacity shredders the industry had, Hinsey explains, but “you need 4,000 to 5,000 tons a day to feed a [large] shredder, and there’s just not that volume of scrap” on the market. Buyers of portable shredders “are saying, ‘I can process a significantly smaller amount, 5 or 10 tons an hour, at three different locations this week, and I don’t have to try to figure out where to get thousands of tons of scrap for four or five days of production in a [large] shredder.’” In other words, he says, you might process less scrap, “but you keep your machine busier more often. The people who’ve got these massive shredders that can only run them a couple of days a week are struggling, while the guy who’s got the portable machine is keeping it busy four or five days a week, and [there are] not enough hours in his day.”

Cost is also a plus. Stationary high-speed shredders can cost roughly $3 million to $40 million for the largest machines. Portable hammermill shredders range from about $1.5 million to $3.5 million; shear shredders range from $450,000 to $1 million, according to those interviewed for this story. And it can be easier to get financing for mobile equipment, these sellers add.

Even beyond the equipment price, “the barrier [to] entry is so much lower” for recyclers looking to add a shredder to their operations, Hammel’s Semler says. “The requirements for a big stationary shredder start with the permitting and zoning for the yard, and the foundation you have to install to get the machine solidly anchored to the ground—and then you’re pretty much locked down to that machine wherever you build it,” he explains. “Having a portable machine is less expensive to start with, and then it’s more flexible and less of a long-term commitment than a stationary shredder.”

Portable shredders also can help reduce a company’s transportation costs. Recyclers who operate 100 miles or more from the nearest steel mill, for example, often can’t economically transport their unprocessed scrap, Newell says. Or recyclers can send portable shredders to natural disaster sites or construction and demolition sites to process scrap, he says. Or, Abenstein says, you can relocate a portable shredder near shipping ports and other transportation hubs to shred unprocessed material before shipping it.

Looking at the big picture, this equipment “empowers the little guy,” Padula says—the small companies that are “tired of being dictated to and somewhat financially restricted by the [big] shredder who holds them hostage. What the small guy wants is to be able to go out there and be in charge of what he does, what he makes, and how he sells it.” Abenstein agrees. “If you’re a small or midsized company, you’re restricted by the price the larger shredder will pay for your material, or [the larger company] could suddenly decide to stop buying a certain type of product, or they could shut their shredder down completely. That leaves you having to sit on your material or find [another] buyer. With a portable or mobile shredder, it gives you better flexibility—you can do it yourself.”

Even companies that own stationary hammermill shredders could find value in a portable shredder, these companies say. Zato’s shear shredder can act as a “preshredder or bale breaker for your material so when you process it in the [large] shredder, you can not only increase the throughput of the hammermill but protect your investment by screening the material for quality and for dangerous material,” Abenstein says. Preshredding also can reduce wear and tear, maintenance costs, and downtime on a stationary shredder, Semler adds.

Rules of the Road

If you’re sold on the benefits of a portable shredder and have an idea of what size and type would be best for your operation, consider a few other factors to ensure you can use the equipment where and how you would like.

Regardless of how they move—on crawler tracks or on one or more trailers—getting these heavy-duty machines on the road takes planning. Find out the weight and dimensions of the equipment when it’s packed for travel, then check with state and local jurisdictions where you plan to travel to determine wide-load and weight restrictions and whether permits are needed, regardless of what the manufacturer guidelines state. Most of this equipment does not require wide-load permits, but a few machines do, including one of four trailers used to transport The Shredder Co.’s Little Rascal shredder and the largest of Hammel’s portable shredders.

Also consider the machines’ environmental impact. Even though portable machines generally require fewer operating permits than installed equipment, environmental laws still apply, and recyclers should be aware of applicable regulations, says Larry Berndt, principal of Wenck Associates (Maple Plain, Minn.), an engineering and environmental consulting firm. “The simple use of a shredder attracts attention,” Berndt says, and to regulators, “shredder is a big, bad word.” Any change to your business practices could affect your operating permits, he notes, and it’s best to be proactive about making changes to your business operations. He recommends operators plan ahead to avoid issues with stormwater pollution, hazardous materials, air pollution, and worker health and safety. “With portable shredders, the environmental risks may be smaller, but risks still exist,” he points out.

For example, make sure that the operation of a portable shredder doesn’t affect your facility’s existing stormwater permit. Update your stormwater plan to reflect the addition of the shredder and best management practices associated with it. As you would with a stationary shredder, inspect material before it goes into the portable machine, and drain or remove liquids, mercury switches, and items that might contain polychlorinated biphenyls. Manage these hazards properly and document what you did with them, Berndt advises. If you can’t tell if such hazards have been removed—if you’re processing a load of crushed cars, for example—audit the supplier’s yard to verify that their practices meet regulatory standards, he says.

The scrap recycling industry as a whole must worry about rogue operators who purchase portable shredders and set up shop at remote or abandoned yards to dodge regulations, Berndt adds. “Just like within any business or industry sector, there are bad actors that give the overall industry a bad name,” he says. “When someone actually hires a portable shredder on a temporary basis with the idea of skirting the regulations … both the owner/operator of the facility and the owner/operator of the portable shredder could find themselves in hot water with the regulators,” he warns.

The Future of Shredding

Many recyclers believe the United States already has too many shredders and not enough scrap in the market to keep the existing machines busy. Will portable shredders make the overcapacity problem worse? Most of the sellers interviewed for this story say no, but The Shredder Co.’s Newell says yes. That might not matter for any one company, he adds, using this story to illustrate his point: Two guys went hunting in Texas. “They’re in the woods, and a bear jumps out at them, so they climb a tree real fast. One guy starts taking his shoes off, and the other guy goes, ‘What are you doing?’ He says, ‘I’m going to drop to the ground and run away.’ The guy says, ‘You can’t outrun the bear.’ And he says, ‘I don’t have to outrun the bear,
I just have to outrun you.’”

That’s what Newell tells people about shredder capacity. “You better be able to run faster than the least-efficient producer. If you can, you’ll still do fine.” To get the most out of a portable shredder, however, companies also need a portable metal recovery plant to separate the materials, he says, because that’s how you create value.

Portable shredder manufacturers expect mobile machines to become more popular in the years to come as they continue to refine their products. Manufacturers of portable hammermill shredders say they’re working on quieter, more fuel-efficient designs with fewer emissions, more durable castings, more horsepower, and lower operating costs. Shear shredder makers are aiming for higher torque, increased capacity, more efficient use of power, and higher density of the finished product. A couple of companies say they’re working on combining several portable machines into a smaller, all-in-one machine that allows recyclers to maximize their investment.

In the meantime, Padula says, portable shredders “will revolutionize the industry… [Large] shredders that cost tens of millions are a thing of the past.” Instead, “it’s better to be little and nimble,” Padula says, which gives you “more fluidity, a lower break-even point, and most important, control of your own destiny.”