Plastics recyclers, hungry for new equipment and processes that increase efficiency, had the opportunity to view at NPE 2006 a variety of shredders and grinders that offer greater capacity, reduced maintenance costs or reduced waste.
Drivers behind the increased interest in efficiency are rising material prices, higher fuel and transportation costs and supply shortages that have many recyclers turning to harder-to-recycle material. The following companies highlighted products at NPE 2006, held June 19-23 in Chicago.
Size Reduction Specialists Corp. introduced its SRS Bridge-Busteran air-powered force-feed control system, which it said forces larger runners into cutting chambers, eliminating downtime due to backup and overflow. The product, inside the hopper, includes a timer and on-off switch.
``It increases capacity without increasing the size of the grinder,'' said Don Maynard, national sales manager for the East Lansing, Mich., firm. ``A lot of companies are trying to operate with less manpower. This ensures that all runners are forced into the feeder'' and prevents shutdowns due to bridging problems.
SRS also introduced its Tri-cutter screenless granulator that reduces regrind particles in three stages - but one continuous operation - to the smaller sizes needed to accommodate small-ton injection presses. Existing SRS bi-cutters can be modified to use the Tri-cutter rotor.
Force-feed granulators from Resource Recycling Systems Inc. in Smithfield, R.I., the North American subsidiary of Herbold Meckesheim GmbH in Meckesheim, Germany, also are designed to increase throughput.
By using augers, rather than gravity-fed hoppers, to force materials into the cutting chambers, the amount of material processed hourly can be increased 50-100 percent, said sales manager Stephen Montalto. He said auger feeding is suitable for wet or dry granules.
``It saves energy costs,'' Montalto said, because a recycler would need ``a much larger machine - or more machines - to achieve the same output.''
B+B Anlagenbau GmbH of Tönisvorst, Germany, introduced to the North American market its dry system of recycling, which it said removes 95 percent of impurities from PET bottles ground into flakes and eliminates the need to pre-wash bottles, reducing water consumption and waste-water treatment problems.
``You can remove 95 percent of the impurities from dry PET flakes without the use of water,'' said Achim Ebel, B+B managing director. ``With wet waste, you are paying a landfill for moisture content and also incurring water-treatment costs.''
The system can process 550-6,600 pounds per hour. The only U.S. user of the technology is United Resource Recovery Corp. of Spartanburg, S.C., which purchased two systems two years ago. Merlin Plastics Supply Inc. uses the equipment in plants in Calgary and Vancouver, Canada.
Ebel said that after large, heavy contaminants such as stones and metal are removed by a pre-sifter, PET flakes pass through a screening cage with a large turning rotor that works against the screen basket to remove 80-90 percent of contaminants. The dry mechanical process uses the friction of the flakes as a cleansing agent, he said. The flakes then are cleaned in a hot washing system and mechanically dried.
Precision AirConvey Corp. of Newark, Del., showcased its new line of 21 PAC plastic pelletizers, made by Plasmac Ltd. of Aylesbury, England. The Plasmac closed-loop pelletizer allows recyclers to capture edge-trim roll scrap and other film waste, convert it to pellets and reintroduce it into the extrusion process with a closed reclamation loop that protects against impurities.
The pelletizers can recycle as much as 1,000 pounds per hour or as little as 10 pounds.
``As the prices of plastic resin and natural gas continue to climb,'' companies continue to look for cost-cutting solutions, said Tom Embley, chief executive officer of Precision. ``Converting waste material into reusable material has never had more impact on the bottom line.''
Erema North America Inc. of Ipswich, Mass., introduced its redesigned, more efficient Model 906T recycling system, which also gives recyclers easier access to components for maintenance. The system, designed for use with low and high density polyethylene and polypropylene, can recycle as much as 450 pounds per hour.
It includes a roll feed and conveyor belt with a metal detector, automatic back flushing screen and hot-die-face, water-ring-type pelletizer.
``For processors, an effective waste-reclaim system is becoming an increasingly important hedge against rising resin prices,'' said Tim Hanrahan, North America vice president for Erema.
The firm also debuted its redesigned 600 KAG edge-trim recycling system with a remote, multiple-machine monitor panel. The 600 KAG allows efficient automatic densification of edge trim, which easily can be weighed gravimetrically and controlled with an output of 150 pounds per hour, according to the company.
Single-shaft shredders from Weima America Inc. of Fort Mill, S.C., elicited praise from Robert Render, president of recycler Maine Plastics Inc. of Zion, Ill., which hauled away more than 500,000 pounds of plastics scrap from NPE.
He said Weima's ability to integrate shredders into a company's operation, in terms of ``how you feed it and how you lay it out,'' is especially valuable to companies that change materials frequently. Render also said the open design gives recyclers access to the rotor, making it easier and quicker to clean. Also, there are not a lot of cracks and crevices where scrap can fall into the machine.
With more recyclers searching for new material sources, devices to identify the types of plastics in recycled items were also on display.
In particular, the line of IoSys near-infrared portable and stationary spectrometers made by GUT GmbH of Stuttgart, Germany, and sold by Powdertech International Corp. of Valparaiso, Ind., attracted attention because of their ability to detect, identify and analyze plastics and their additives and to screen polymers for re-use.
The IoSys tools provide direct analysis of plastic parts, films, foils, foams, granules, bottles and other plastics-containing materials on an integrated display with an almost-instantaneous measurement time.
``The spectrometers can analyze more than 1,800 types of plastics, replacing the burn-and-sniff method used by many recyclers that emit toxic fumes,'' said Powdertech Vice President David Beckwith. ``The analysis gives the user all the elements contained in the material, as well as any fillers and flame retardants,'' at one-third the price of competing products, he said.