Evolving MRFs

Features - MRF Design

Changing material streams prompt material recovery facilities to integrate new technologies and processes.

July 30, 2019

© Tierney / stock.adobe.com

Editor’s Note: Commentary shared in the first half of this article is edited from a presentation given in November 2018 by Nathiel Egosi, president of RRT Design & Construction, Melville, New York.

When it comes to recyclables, supply-and-demand pricing is a complicated conversation that’s seldom influenced locally. Pricing factors include macroeconomics, demand from export markets, capacity adjustments at mills and tariffs.

Depending on the recycling industry’s role in the global economy, it’s either a winner or a loser. Today, material recovery facility (MRF) owners and operators are on the losing side, and consuming mill operations are winning. Mills are finally reaping money they had been losing for years because of high export demand. To compete in past years, domestic mills had to pay MRFs much more for recyclables to feed their mills.

With the current slump in export demand and a general lack of liquidity, domestic mills can get all the recovered paper and plastic they want very inexpensively. For mills, profits are rolling in.

The real story here is that the money has simply changed hands and the recyclables coming to MRFs are different. The recycling industry must understand that recyclables always will be changing—what a MRF received years ago is not the same material it is receiving today.

For instance, a MRF from the 1990s, even if it upgraded over the years, is not designed to process what is being collected today. Also, newspapers are one of the fastest shrinking commodities in the U.S. as many newspaper outlets are downsizing or shutting down. For instance, The Vindicator newspaper, Youngstown, Ohio, has announced plans to shut down at the end of August.

On the other hand, old corrugated containers (OCC) are growing at a significant rate as a result of the Amazon effect.

Joaquin Mariel, vice president of operations at Balcones Resources, Austin, Texas, says he has noticed an increase in OCC coming to MRFs the last five years as a result of Amazon and other direct-to-consumer services.

“We’re having to get creative with equipment manufacturers in how we capture that material,” Mariel says.

Additionally, plastic packaging continues to increase, but the packaging itself is more complex.

Mariel adds that polyethylene terephthalate (PET) bottles are lighter than they were five to 10 years ago.

All these changes can be referred to as “the evolving ton.”

MRFs also have the current challenge of determining what can and cannot be recycled. The industry used to agree that a material was recyclable as long as there was a market for it. Yet, markets fluctuate, so this definition is flawed. Government policies have emerged to help dictate what is and isn’t recyclable.

With today’s evolving ton and changing rules on what is and isn’t recyclable, a MRF’s design can’t be stuck in the past. It must evolve with the materials and regulations.

Optical options

With the changing material stream, MRFs are adding more optical sorters to their processing lines. About a decade ago, optical sorters typically concentrated on plastics. Today, MRF operators also use this technology to sort paper.

“Five years ago, you never saw opticals on the fiber side of the business,” says Bob Cappadona, vice president at Rutland, Vermont-based Casella Recycling. “Now, you see more opticals used to extract contaminants from fiber. And that’s really because the material mix has changed. You see less soft mix, less newspaper. When the incoming stream changes, you have to make adjustments.”

From left: Jason Haus of Dem-Con Cos. Inc., Jim Marcinko of Waste Management Inc., Norman Kraft of Niagara Recycling and Austin McKnight of Casella Recycling at the 2018 MRF Operations Forum in Chicago
Photo by Austin Friedline with Phierce Photography

Adding optical sorters can lead to a cleaner paper stream. Mark Henke, senior recycling manager at Phoenix-based Republic Services, says that company has installed optical sorters in an effort to improve its recovered fiber streams. He says he has noticed gradual improvements as a result.

“You still have to have a quality-control person after the optical just to make sure you’re getting all materials, but it gives you a much better chance of hitting specifications,” Henke says. “You don’t need as many people on the line.”

He adds that optical sorters can help to reduce labor, increase throughput and produce a cleaner secondary commodity.

Today’s optical sorters also are more effective than those that were manufactured earlier in the past decade. Cappadona says the optical sorters of a decade ago were clunky and tough to maintain; today, that’s not the case.

“Opticals 10 years ago were rated at 88 to 90 percent effectiveness,” he says. “Today, you won’t see it under 95 percent. [Opticals] are made to last.”

Bill Keegan, president of Dem-Con Cos., Shakopee, Minnesota, says optical sorting technology is “improving rapidly,” adding that an optical sorter that Dem-Con installed six years ago already is obsolete.

“I think optical sorters will continue to improve and be augmented with new tools, including AI (artificial intelligence) and other sensing technologies,” Keegan adds.

Integrating robots and AI

Another tool that might grow in popularity in MRFs is robots. Robots can be especially helpful at reducing manpower on a line and act as a last-chance capture tool.

“They seem to be most useful in quality control after optical sorters or perhaps at the end of a residual line to capture anything that might be missing from a commodity standpoint,” Cappadona says.

Also, Keegan says robots can help in an age when unemployment rates are low.

“We’ve got 3 percent unemployment rate, but the national average is at 3.6 percent,” he says of the company’s Minnesota town. “[With robots], we’re reducing our needs—a robot replaced the job of someone we couldn’t find as opposed to kicking people out of jobs.”

Robots also don’t require a large footprint, so Keegan says they might be useful in some applications that lack adequate space for an optical sorter.

“Opticals require a larger footprint with a speed-up accelerator belt, and if a belt goes down, your system is down,” he says. “Robotics can hang over an existing belt, and if they’re not working, you can staff manually.”

Keegan adds that he doesn’t think robots compete with optical sorters. “There’s applications for each and operational constraints that lead you to use one or the other,” he says. “I see them as two tools in the toolbox as opposed to competing—like a wrench and a plier. You can use both, but they’re different tools.”

Another tool that might grow in popularity in MRFs is AI technology. Keegan says AI can help MRFs gather real-time metrics on inbound material and contamination data.

Without this type of data, Keegan says MRFs often rely on inspecting one bale out of a batch to check for contamination. However, AI can inspect material flowing through on a belt to provide real-time read on contamination.

Expanding yet simplifying

Beyond equipment and technology, MRFs may evolve to become more flexible in their layouts and processes. Mariel says MRFs have typically focused on accepting only residential single-stream material or only commercial material. However, he says he thinks MRFs might evolve to diversify their incoming material streams to survive in the future.

“There’s a need to diversify the capabilities of these facilities,” he says. “It costs a lot to build them and operate them. There’s no reason for them to not be flexible.”

MRFs also must improve communication. Henke says it’s important for MRF operators to simplify their messaging on what is and isn’t accepted at the MRF to partners in municipalities so these stakeholders can better educate their communities.

Because a list of what a MRF doesn’t accept might be very long, Henke suggests simplifying that message and communicating a short list of items that are accepted.

Regardless of which technologies or strategies MRFs choose to embrace, MRF operators across the U.S. will make changes to address the evolving ton.

“MRFs have to adapt,” Cappadona adds. “A MRF from 20 or 15 years ago has to be designed differently in order to find good markets; you have to make those adjustments.”

The author is managing editor of Recycling Today and can be reached at msmalley@gie.net.