Doing it the first time
When Gershow Recycling of Medford, New York, knew it needed a new eddy current plant to sort the ASR (auto shredder residue) generated from its 120-inch, 8,000-horsepower shredder, the company invested six years to envision, design and build a 70-ton-per-hour plant.
“We did not set out to build the largest nonferrous plant in North America, but that’s what we ended up doing,” says Kevin Gershowitz, president of Gershow Recycling. “That was only possible because we have such a talented team here, and we were fortunate to work with many great partners.
“We did a lot of work to understand the production rate we needed to ensure our eddy current plant no longer held us hostage,” he says. “We identified that none of the available feeding systems could do it.”
Gershow needed a batch feeder that could maintain the material flow. The company created an initial idea for a massive feeder it believed would work. “We shared this idea with several industry suppliers. They told us it would not work and were unwilling to build it,” Gershowitz says.
“When we shared the idea with the team at U.S. Conveyor, it was a different story,” he continues. “They were sure they could build it and confident it would work as desired.
“U.S. Conveyor went beyond being confident they could build the batch feeder,” Gershowitz says. “They guaranteed it would work and said if it did not, they would give us our money back. That was more than we expected.”
“We love partnering with customers like Gershow—customers who want to push the envelope and solve problems like this that have plagued our industry for years,” says Troy Graves, president of U.S. Conveyor Technologies, Mackinaw, Illinois.
We’ve built hundreds of feeders, but nothing of this scale,” Graves says. “To get the job done, our engineering team set out understanding the customer expectations, modeling the power requirements and understanding the forces it would take to move this huge amount of material at a very precise rate.
He continues, “The process proved out what we knew—that while this was something new and different, it was going to work just fine.
“It was a larger scale, but our modeling and experience combined to assure us that not only could we built it, but it would deliver exactly what Gershow needed.”
The Mega Batch Feeder is born
Graves says, “We set out by reviewing all the past failures of large-scale batch feeders in the industry. Most feeders are in the 10-20 tons of ASR range, but nothing of this scale. And when you evaluate the largest feeders in the industry, most are not working as intended; usually handling no more volume and feeding no faster than our standard 20-yard feeder.
“To get the job done, we needed to rethink the single machine designs most commonly found. We settled on using a conveyor and vibratory feeder in tandem,” Graves says.
The feeder is 70 feet long and 8 feet wide. Fully loaded, it allows for approximately 115 tons of material (or 240 cubic yards of ASR) to be loaded. It then seamlessly meters the materials into the plant’s elaborate screening system.
“One of our favorite features of this design is its incredible flexibility for future applications,” Graves says. “It can smoothly feed a system at a rate of 10 tons per hour but reach to 150 tons per hour. We can change widths, lengths and orientations to fit into available footprints. Additionally, we believe this design is ready for just about any material you can load into it, even shredded steel.”
A huge benefit of a feeder of this scale is that a user can load it up and let it run. This unit is fully automatic and does not require an operator. “Our old plant required three payloaders and two skid steers just to feed the plant and clear material. It was nonstop; our equipment was literally hostage to the plant,” Gershowitz explains.
The Mega Batch Feeder (MBF) discharges to a vibratory feeder that precisely delivers material to the infeed conveyor. The infeed conveyor’s belt scale has a PLC interface to control the MBF’s motors, allowing continual flow adjustment, ensuring the system maintains a rate of at least 70 tph.
“Today we are running the plant with one loader—a single loader does it all. It’s totally liberating and allows us much more flexibility in our operations,” Gershowitz says. “None of this would be possible without the MBF built by U.S. Conveyor. It was not the lowest cost option, but it was the best solution.”
Also from U.S. Conveyor Technologies:
The zorba produced by the Gershow Recycling plant enters a sophisticated counting regimen. Each of the eight lines drops onto a designated scale conveyor. That scale conveyor incrementally moves until it reaches a predetermined weight, then it clears itself and begins counting again.
This highly controlled process allows the plant’s control system to continually record precise production levels for each zorba fraction as well as the plant’s overall production.
“Traditional belt scales do not work when weighing low volume products like zorba, especially when the total flow is sliced into eight fraction sizes. It required some ingenuity to develop this type of scale,” says Chris Melenick, sales engineer with U.S. Conveyor, Mackinaw, Illinois.
“We are very pleased with the accuracy we are seeing and believe this approach holds great potential for a wide variety of applications in the industry,” he continues.
Value from the ferrous
Many operators let the ferrous recovered from their DSRPs drop into their residual lines. Gershow Recycling made the decision to recover that material.
“By running the residuals through a Spaleck Cassette screen and U.S. Conveyor Polisher, we’re able to both reclaim and clean up the remaining ferrous fraction,” Graves says. “This allows that fraction to be added back into Gershow’s outbound ferrous material, turning it into revenue while avoiding landfill fees. It’s a great use of the cassette screener and polisher.”
The plant was designed to be open, airy and have great lines of sight. Achieving the openness of the plant lies in part with U.S. Conveyor’s use of its proprietary banana conveyors. These conveyors allow for slopes not possible with traditional conveyors.
The unique banana conveyors were integrated into the plant design in numerous areas. They provide perfect material flow from one processing phase to the next but also help to deliver the open access Gershow Recycling was seeking.