Problem: A national pallet management, sales, recycling and reverse logistics company needed to increase its revenue by getting more value from its wood waste.
When Rehrig Pacific Logistics (RPL) needed help designing a system to more profitably utilize its wood scrap, the company turned to custom manufacturer and systems integrator Cresswood Shredding Machinery from Cortland, Ill.
RPL produces large volumes of wood waste and needed a way to increase its revenue after a downturn in the pallet market.
“What drove our need for more value from wood scrap was the collapse three years ago of a key market in ‘# 2’ repaired pallets – we were left with a loss in revenue,” said Todd Rodewald, general manager of recycling and washing services at RPL.
RPL had identified a target market and product for utilizing wood scrap; a finished composite board product for furniture and flooring manufacturers and the building trades. But since its feedstock would include different types of wood waste, including whole pallets, RPL needed a system that would process its feedstock into uniform chips.
The company contacted Cresswood to collaborate on preliminary drawings and develop a complete system for its new facility. The result was a system that includes conveyors for bringing in the material, a pre-shredder for breaking down large material and dual wood grinders. The Cresswood Chip Processing System is a two-step system designed and engineered to meet the demands of RPL’s end-product and the high volume processing requirement of 20,000 pounds per hour.
“The raw material source included truckloads of spent GMA pallets at some really big volumes, and we had to process down to a very uniform product size,” said Jack Cress, chief executive officer of Cresswood. “A two-stage system was essential to satisfy RPL’s requirements.”
Cress said that additional factors drove the design of the size reduction process.
“The first stage of the process starts with the pre-shredder to enable batch-loading of whole pallets in quantity while being very tolerant of tramp metal events, and the second stage optimizes our dual HF-60-100 Destroyer grinders to provide superior quality chips at high volume rates.”
Because of the feedstock being used, RPL also required a metal extraction system.
“Due to the sensitivity of our equipment, it is critical that metal contamination is eliminated,” Rodewald said. “Our feedstock is full of embedded nails, so Cresswood engineered a metal separation system that is deployed at crucial transfer points in the process. It features both primary and secondary crossbelt separators, and a magnetic head pulley.”
Rodewald also focused on eliminating downtime issues and building in redundancy with the grinding system to facilitate preventive maintenance (PM).
“We might have over-engineered the system, but we maximize processing flexibility with the dual Cresswood grinders. We can run both simultaneously, choose which grinder will process, or perform PM on one while the other processes,” he said. “Uptime is critical for production, and our experience has given RPL a preference for the low-RPM Cresswood grinder. The reliability of the technology, simplicity of PM routines and energy efficient electrical drives are all pluses for RPL.”
RPL’s composite board product is now on the market, thanks to Cresswood’s help in designing a system that produces chips that are so uniform that RPL could bypass the flaker, if required. Rodewald said the system is a perfect match for RPL’s feedstock and product, and that after conducting a maximum throughput test, processing 25,000 pounds per hour, the result exceeded RPL’s goals.
“Cresswood was with us every step of the way, worked with process flow, took our space constraints and delivered a system so well-calibrated that it dropped right in to our pad layout,” Rodewald said. “We fed off the ideas of each other, and Cresswood stepped up to our challenges.”
For more information on Cresswood, call 800/962-7302 or visit www.cresswood.com.
