Newer and Better

Spurred partly by European recycling mandates as well as by the desire to increase profits, new sorting and separating technologies are changing the face of auto shredder downstream systems.

Manufacturers and research firms from throughout the world are commercializing technology that they say will provide recyclers with purer materials streams and greater recovery values.

While much of this effort continues to focus on metals recovery, researchers are also examining how to handle the post-shredder plastics stream for recycling possibilities.

MEDDLING WITH METALS. As has always been the case with auto shredding operations, the recovery of every possible ounce of metal remains the highest priority.

The bullish metals markets of the past two years have only served to accelerate the deployment of additional equipment to extract metal from the post-shredder materials stream.

Research into how to most efficiently identify and separate metals from plastics and different types of metals from each other has been ongoing for decades. With the bull markets in place, recyclers are showing a willingness to try new technology that has recently entered the market.

While eddy current units have been common for several years, auto shredding plants now commonly have more than one unit deployed, and in the current bull market recyclers have also been adding larger units and newer units that can promise greater returns.

Beyond the eddy currents, additional automated systems are being used that are increasing both the amount and the purity of metal recovered on site at shredding facilities.

Induction sorting devices featuring European technology and distributed by companies such as SteinertUS, St. Petersburg, Fla., and Wendt Corp., Tonawanda, N.Y., have been designed to capture stainless steel pieces and insulated copper wire fragments that might escape traditional magnetic equipment.

Bill Close of Wendt Corp., which represents the SSE equipment line from Germany to the United States market, says the company is now offering an additional post-shredder separating and dry sorting device known as the X-tract that incorporates X-ray technology.

"The goal of this machine is to upgrade the eddy current ‘Zorba’ product that folks are already producing," Close says. He adds, "This machine uses X-ray detection to identify the atomic density of particles, precisely identifying what base metal it is." Immediately after non-aluminum objects are identified in the Zorba stream, they can be separated using air jet nozzles, says Close.

He says that the equipment has been field tested in Germany and is now being used there in applications where it sorts up to 10 tons per hour. Wendt Corp. has been taking select U.S. scrap company customers to Europe to see the X-tract in action.

The goal in offering the technology to auto shredding plant operators is to create an aluminum scrap stream that is pure enough to go directly to aluminum scrap consumers. "Since the majority of flow volume will be aluminum—perhaps 80 percent—the X-tract is designed to shoot anything not aluminum out of the stream," says Close, including irony aluminum or pieces of aluminum with contaminating attachments.

While calculating the return on such an investment can depend on market prices, Close offers, "We are anticipating that the X-tract Separator will typically generate 10 cents per pound of $200-per-ton incremental revenue for shredder operators by allowing them to sell direct to the secondary aluminum scrap marketplace."

AVOIDING THE LANDFILL. While metals recyclers take interest in efforts to profitably recover every ounce of metal, recycling requirements in the European Union (EU) and other parts of the world are spurring research into how to recycle the non-metallic portion of the post-shredder stream.

Because EU directives concerning end-of-life vehicles (ELVs) target the auto shredder residue (ASR) stream, much of the research has been centered in Europe.

A company called SiCon GmbH, based in Hilchenbach, Germany, has been developing and testing technology that can separate some plastics by resin type and then make up to three desirable products from the plastic portion of the ASR stream.

SiCon, working at times in cooperation with Volkswagen (VW), has been testing its technology at a shredding facility near Antwerp, Belgium, and at a pilot plant created in Willebroek, Belgium. "During this period, the process engineering has been thoroughly tested for use on an industrial scale," according to a SiCon news release.

A technical paper co-authored by SiCon Managing Director Heiner Guschall and Project Managers Florian Haug and Sebastian Schulke, explains that the VW-SiCon process can produce several products: shredder sand; shredder fibers; and shredder granules that can be split into a PVC-rich and a PVC-poor fraction.

These granules are not yet being produced with an eye toward making them available as secondary resins, but rather as a furnace "reducing agent" to take the place or reduce the amount of heavy oil or pulverized coal that might otherwise be used. The SiCon report indicates this material can substitute at a 1:1 ratio for coal or heavy oil, creating a desirable market for the separated ASR material.

The authors also write that they continue to "work intensively on the mechanical separating of some parts of the ASR" so that plastics separated by resins can eventually be offered as secondary resins for use in applications that consume secondary plastics.

The shredder fibers portion of the SiCon process stream is being targeted for end markets as an incineration sludge additive for the gasification plant energy market. The shredder sand, which is high in iron and contains some other metals "can be utilized in metallurgical applications such as slag builder in shaft furnaces," according to the SiCon report.

Closer to home, the North American waste-to-energy market is the focus of a system already being offered to the market by ILS (Innovative Logistics Solutions) Partners, Palm Desert, Calif., and by Pyromex AG of Switzerland.

The ILS system uses "ultra-high temperature gasification" to accomplish what the companies call "destructive distillation" of the largely non-metallic ASR stream.

In addition to several installations in Europe, ASR from a shredding plant in California is currently being used to demonstrate the ILS system’s ability to produce "intense energy in the absence of oxygen [that] reduces the material [by] approximately 98 percent," turning most of it "into a combustible gas and the balance [into] a non-hazardous, non-toxic inert basalt that can be used in construction, road base or anywhere sand can be used."

ILS Partners and Pyromex claim shredder operators who deploy their system will eliminate hauling and disposal costs and potential downstream environmental liability.

They say their system, which can be scaled to match a shredding plant’s output, "creates no harmful residue or emissions, proving environmentally friendly and a profitable solution for the disposal of ASR. Five hundred tons of ASR will ultimately be disposed of daily to generate approximately 30 megawatts of electricity."

Herb Teague of ILS Partners says the technology has proven commercially viable and has been in use in Europe for five years.

LAB WORK. Another North American-based effort is being led by the Vehicle Recycling Partnership (VRP), which is largely funded by North America’s automakers. The VRP has been working with the Argonne National Laboratory in Illinois and the American Plastics Council (APC) to study ways to convert ASR into end market-ready products.

Part of that effort has included what Argonne calls its "six-stage plastics recycling plant," which it describes as a "continuous, multi-stage plastic separation plant."

"The new recycling process works for just about all mixtures of plastics generated by industry," according to a statement on the Argonne National Laboratory Web site. "The new plant advances the state of the art because it . . . can be used to separate plastics with overlapping density ranges—and it can do that cost-effectively. One of the most noteworthy features of the process is its design capacity: It can process 1,000 pounds of plastics per hour."

More research is being conducted to see to what extent the process can affordably recover selected plastics from ASR. Currently, Argonne, the U.S. Department of Energy, the Vehicle Recycling Partnership and the APC are in the midst of a five-year, multi-million-dollar, cost-shared R&D research agreement at Argonne’s facility.

The APC has an interest in the research because it is eager for its member companies to achieve greater inroads into the vehicle component market. While trends toward lighter weight materials have been helping plastic take away some metal component market share, mandates for recyclability could halt that trend unless the plastic portion of ASR becomes more recyclable.

But in all likelihood, if advances in plastics recycling research begin to turn the plastic portion of ASR into a desirable commodity, scrap metal recyclers will gladly consider themselves multiple-material recyclers.

The author is editor of Recycling Today and can be contacted by e-mail at btaylor@gie.net.

European Vocation: Click here to read the complete report prepared by SiCon concerning its ASR recovery research,