The latest models
"Our Strobe 1500 allows for 3-product separation - ferrous metals, nonferrous metals and non-metallics," continued Steelweld Enviro's Andrew Mackle. "The feed speed of material over the eddy current drum and the speed of the eddy drum are variable, to cope with a range of product types, and the unit can be powered by an on-board 65-kVA generator or plugged into mains electricity. It also features low-pressure crawler tracks so it can be used on softer terrain."
He said they have created a complete ECS system on tracks, including discharge conveyors and on-board power.
"Our design brief was to build a reliable portable ECS that allows the customer the freedom to bring the Strobe 1500 to the material, unlike static ECS applications where the material must be brought to the unit to be processed," continued Mackle.
"The fact that the unit is fully portable allows the customer to separate various material types that they might not have considered before, rather than having the ECS in a fixed recycling plant with a single waste stream."
Eriez' latest model eddy current separator was designed for very fine (-1/4-inch) sized material. According to Chris Ramsdell, the model UHF (Ultra High Frequency) ECS is a high-strength and high-frequency machine designed so that, when material is sized properly, customers can reliably recover bare copper wire and microfine cast aluminum. "We've found that, with our UHF ECS, ASR processors, for example, are recovering an additional three to five percent of additional fine zorba that had previously been sent to landfill," he said.
IMI's Dennis O'Leary said their initial product offering started with an over-2-inch particle size removal and an under 1-1/2-inch particle size recovery unit. They then moved on to a stronger, higher-polarity unit designed for material that can be used "across the board," from +5-inch to < 3/8-inch particle sizes. "As we move forward we will continue to develop product that flanks our existing technology and will give the customer the most marketable product," said O'Leary. "We want to be seen as a strategic partner who brings value, versus a parts supplier."
SteinertUS' Robert Broughton said Steinert has never waivered on their commitment to improve the performance of eddy current separators, continually evolving the product line to match a variety of different separation tasks. He said Steinert's innovation in this space has recently yielded several new product lines, most significantly development in the microfines and <5mm areas.
"Steinert's new EddyC Fines is specially developed for recovering fine nonferrous metals and incorporates a number of innovations from magnetic design, splitter adjustment capabilities and maintenance-friendly options, including a 10 minute belt-change frame design," he said.
Chris Ramsdell pointed out that two of the most important elements for a recycling operation to consider, when thinking about adding ECS technology, are the percentage of recoverable nonferrous metals in the material to be processed, and/or material grade improvement.
"This is information that we're able to supply to the customer prior to them making a purchasing decision," he said. "Eriez Magnetics offers material testing services at our Central Test Lab in Erie, Pennsylvania. We're able to supply magnetic separation and eddy current separation testing depending on the application requirements. At the conclusion of the testing, Eriez will furnish a complete test report which includes weight splits, material yields and high resolution photos of the separated materials." Buyers should make sure they do their research and find out which waste streams an ECS is best suited to, said Steelweld Enviro's Andrew Mackle. Static vs. mobile configurations should also be considered.
"Complete static eddy current systems can be expensive to design and install, only to find out they're not giving the end product as required," he said. "This is where the Strobe 1500 has a huge advantage." Because it is mobile, "it does not tie down a customer to a single material type.
"It's also important that time is spent so the system is set up correctly," he continued, adding that existing equipment is another important consideration. Buyers should consider what equipment they have in hand, and how it might help maximize results when used in tandem with an ECS.
"Better results may be achieved with additional processes in place, before feeding any material onto the ECS," added Mackle. This can be achieved with shredding and screening equipment, and "by having an even bed height of material passing over the eddy current drum, via a vibrating pan feeder."
Steinert's Broughton advises his buyers to look for eddy current separators that are specifically matched to the size and makeup of the material to be recovered, and for machines with excellent reliability and serviceability.
He said the next most important variable to understand is ensuring that the capacity of the eddy current is not exceeded and to purchase the correct width unit to maximize results.
"In the past, eddy currents were sometimes only used to recover the ‘cream of the milk' as quickly as possible," he said. "With the new economics of large-scale recycling, every percentage point of metallic value is essential to the profitability, or lack thereof, of the enterprise."
According to IMI's O'Leary, when purchasing an eddy current or magnet, one of the most important considerations is the customer's comfort level with the company and staff supplying and supporting the equipment.
Questions buyers should ask include: "Is the company leading us to the equipment that will solve our problem or selling what they have to sell? Are they going to be around when we need them? Will they take care of any problems that may arise? Do they keep spare parts on the shelf and are they reasonable priced?" "Eddy current technology, in and of itself, is fairly basic," said O'Leary. "You can buy a great piece of equipment and then rue the day you bought it if you can't get help when you need it."
Changing materials, Artificial Intelligence and new profitability
Going forward, Steelweld Enviro points to the biomass and waste-to-energy sectors as ones to watch for growth in applications of ECS technology."In the U.K. we're seeing a higher level of separation requirements, especially in the wood and waste biomass industry," said Mackle. "In these applications there must be zero metallic presence before the material enters the burners to generate electricity. With renewable energy on the increase, there is more demand for ECS systems to cope with organic biomass fuels."
He continued, "With many countries adapting to renewable energy, there will be an increase in demand of a clean biomass product. The Strobe 1500 reduces the amount of manual labour required with a consistent and repeatable level of clean material that is separated into three individually defined stockpiles."
Eriez' Chris Ramsdell said a trend they are noticing in the MRF equipment sector currently is the increase in AQC (autonomous quality control) technology being introduced to the market, adding that ECS will play a role in any new MRF landscape.
"The Max-AI technology now offered by NRT uses vision systems and artificial intelligence to identify each item and a robotic arm to lift and sort each piece of material to its proper location," he said. "This equipment is reducing the need for manual pickers even with a more heterogeneous material stream."
By installing an ECS upstream of AQC and artificially intelligent sorters, recyclers "can greatly reduce the burden of material that these systems are required to sort," he said. According to Steinert's Broughton, over the coming months and years ahead, there will be a continued focus on fines and microfine particles in the eddy current separator sector. "We describe these particles in several different ways, but historically, much of the value in material streams (<5mm) have gone to waste or landfill," he said. "These streams can be substantial revenue adders and do not involve changing current inbound material costs.
"Many new separators are generating new money or new revenue streams for operations," continued Broughton. "This can significantly increase profitability or competitiveness within a region."
One final trend going forward, said Broughton, has to do with the need for the industry as a whole to adapt to an ever-restrictive and demanding end user marketplace. "Product metallic purity is very important, but long-term, moving from a mixed metal stream to furnace-ready base metals is the trend," he said. "Eddy currents, along with X-ray or other refinement technologies are critical to ensure access to this market and optimal material values." RPN
This article was originally published in Recycling Product News, October 2017, Volume 25, Number 7.