The key to the shredding business is to get everything of value you can out of the material. And while the sensor sorting equipment needed to process that material can be costly, to many it's well worth the investment.
For Adam Weitsman, president of Upstate Shredding LLC, Owego, N.Y., sensor sorting of scrap metals isn't just about subtle distinctions for finicky customers, but about being able to market every last bit of metal that exits his new megashredder.
"Part of the system is upgrading scrap, part is separating it and part is capturing every last piece that we can. We produce about 700 tons of waste a day. For 11 years we dumped insulated wire into landfill. Today, insulated wire is $1.60 a pound and we've been losing 14 tons a day being dumped in the landfill. That's more than $42,000 a day," he said.
"I think the next technology is for plastics. Eventually we'll use color-sorting equipment to separate the plastics by color and then market the plastics. We use that now to separate the reds and the yellows" among the metals—the brasses from copper—"and X-ray is used to separate the sheet from the cast." Separating out non-magnetic stainless steel requires yet another sensor position.
The X-ray and color sensors are accompanied by a more traditional technique at Upstate Shredding, which is sorting by density. That's an approach some industry observers view as obsolete.
"Our technology uses sand. It's a lot more environmentally friendly. In the old days you used liquid," Weitsman said. His nonferrous facility receives all materials from the shredder output that don't cling to magnets.
But is the investment cost effective? Chinese buyers are often willing to pay generously for mixed nonferrous zorba shreds, destined for sorting by hand using inexpensive labor.
"Zorba's not always priced high," Weitsman said. "Zorba is a very, very volatile market. Sometimes the London Metal Exchange (aluminum contract) goes down and zorba goes up. Sometimes vice versa. Zorba takes on a life of its own."
He estimates that Upstate Shredding has invested about $20 million over the past two years to improve nonferrous sorting, and he expects advancing technologies to require significant upgrades every few years. At the core of the yard's recent capital spending is a megashredder able to produce 450 tons per hour, up from 225 tons previously, which is scheduled to begin operating commercially in April.
Another executive at a nationwide scrapyard chain said that 98 percent of nonferrous shredder output now goes to Asia as zorba (mixed nonferrous).
"When we first started making zorba, a large portion of our zorba went domestic. Years ago, it would have gone to Huron Valley (Steel Corp.), Audubon (Metals LLC) or MRS (Metal Recycling Services Inc.)," longtime operators of heavy media separation plants that ship their output for melting at secondary smelters and other recycling plants, the executive said. But Chinese buyers began serious buying of mixed nonferrous around 2000.
"What Huron Valley and the other folks are doing now is they're selling to the same people I am. The end-users are in China or the Orient. They aren't in the U.S.," he said, noting that the shrinking of U.S. metal industries has become problematic.
Huron Valley Steel created a high-tech nonferrous sorting facility some years ago that was eventually shuttered. "Huron Valley spent millions of dollars with this imaging program outside Detroit. It was unbelievable. After it was all said and done, it cost about a nickel a pound to sort, whereas the Chinese are at about a quarter of a cent a pound," the executive said. "So the technology was great, but it was inefficient because it cost so much."
Mitchell Padnos, executive vice president of sales and marketing at Louis Padnos Iron & Metal Co., a regional chain based in Holland, Mich., said higher prices for stainless steel scrap have prompted his company's techies to reconfigure the sorting process. "Today I just learned about zurik. It's a shredded stainless steel" that also contains mixed nonferrous, even insulated copper wire. "We're doing it and I wasn't even aware it had a name," he said.
It's disruptive to turn sensor-based conveyor lines off and on in response to market cues. "You can simply blend things back in if you have to," Padnos said. "That's part of our upbringing as a foundry supplier. You always keep things separate because you can always add it back in later. It's the style that we operate under. It would be worse if you go back and forth with your employees and say we're going to do it this way one day and another way the next day."
The company's shredders are located in Holland and Grand Rapids, Mich., and the material from both shredders goes through sortation equipment at an intermediate location in Grandville, Mich.