Every recycler knows that the success of its operation is wholly dependent on the quality and efficiency of its sorting processes.

Melimax, a construction and demolition (C&D) recycler based in Chateauguay, a suburb of Montreal, had been struggling with efficiency issues at its facility in recent years thanks to lackluster sorting system performance that required several passes for the same material and a large number of manual sorters.

“We had quite a few issues with our old system, but the main pain points were the double and triple handling of the material to bring it up to purity standards, while having an enormous amount of pickers. We were aiming to decrease our number of pickers as much as possible while having a ‘one in, one out’ system where whatever came into the system came out as a final product or trash,” Mario Landry, president and owner of Melimax, says.

At the beginning of 2020, Landry began consulting with Sherbrooke OEM about possible solutions for these issues. According to Billy Brasseur, marketing manager at Sherbrooke OEM, the company made the proposition to implement new sorting technology at the Melimax site to increase their recovery rate of both materials exceeding 2 inches in size and fines material, as well as reduce labor costs.

Skeptical at first, the facility’s management quickly became enthusiastic when presented with the first technical sketch and the financial provisions of the project. According to Brasseur, Sherbrooke OEM mapped out the entirety of the project and shared plans in great detail, not only on the technical side, but also regarding the financial implications of the project centered on improved recovery rates.

After initial discussions that allowed the company to see the value in upgrading the site’s equipment, Melimax signed off on a total sorting system overhaul.

Manufacturing and design of the system began in May 2020. Installation commenced towards the end of June and was completed by early October of last year. Melimax began operations with the new system as soon as installation was finished.

According to Brasseur, “The system was built from scratch. We did not use anything from the old system. The core difference between the system’s new equipment, however, was the implementation of optical sorters as well as various equipment to sort the fines portion of the material.”

A vision thing

Up until recently in the C&D universe, only sizeable pieces of wood could be easily recovered, Brasseur says. That has changed along with the advent of more sophisticated sorting methods.

Brasseur says in order to help Melimax better recover its wood, Sherbrooke OEM advocated introducing optical sorters, which had been proven successful at other C&D sites.

Brasseur says optical sorters are ideal for this application because they have the ability to perform hundreds of thousands of ejections every hour. This method of sorting has a capture rate between 95 and 98 percent, the company says.

“Now, every piece that is larger than 1/8 inch in size is recoverable, which represents a huge step forward, as it now allows the recovery rate of wood to exceed 95 percent in C&D facilities,” he says.

According to Brasseur, the ability of optical sorters to differentiate between desirable and undesirable material is one of the main selling points of the system.

“There will always be unwanted material that is ejected with the desired material. We call this the dragging factor, and it is not often considered when talking about sorting, when in fact it has a substantial effect on both capture rate and purity of your material. The dragging factor is caused by the fact that unwanted material is either too close to the desired material or simply attached in some way to the desired material,” he says.

Brasseur says when programming the ejection parameters of the machines used at Melimax, the company made sorting out some of these unwanted materials a priority.

“By replacing quality control done manually with optical sorters, it was possible to increase the quality of the wood, as well as sort out the melamine, embossed panels and plastic, which allowed the production of two distinct wood grades with interesting value,” he explains.

Feeling fines

When it came to treatment of the fines material, Sherbrooke decided to design the system in a way it had been doing for years in the southern parts of the United States, which is to remove the 1/8 inch fines from the rest of the 0- to 2-inch portion of material recovered. This was done to recover not only the wood in this fraction, but also the aggregates, which represented a substantial portion of the material.

“The startup of the Melimax facility made us quickly realize that [separating the 1/8 inch fines from the 0- to 2-inch portion] reduced the total volume of the 0- to 2-inch material from 30 percent to less than 15 percent,” Brasseur says. “Furthermore, observations to this day continue to demonstrate that there is just as much aggregate in the 0- to 2-inch fraction than in the 2 inches and above portion, which is not negligible considering that [that portion of the 0- to 2-inch material] is not usually recovered at all.”

Landry says that thanks to the improvements of its sorting system, Melimax is now able to process 50 tons per hour, averaging between 400 tons to 800 tons a day. Not only have improvements at the site enabled better recovery of materials, Landry says the new system has helped the company better market its products.

“The first improvement we saw was that we got our pickers down to five from our initial number of 25—which represented a major expense for us. Not only that, but we get better quality in our products with the Sherbrooke OEM system since it’s fully automated. We’ve also seen an increase in our uptime and our throughput per hour,” Landry says. “Perhaps the biggest benefit we have with this system is that fines materials are sorted. Being able to retrieve both wood and aggregates from that fraction has had a big impact for us.”

The author is the editor of Waste Today and can be contacted at aredling@gie.net.

Founded in 2014 by John Hanselman and Kevin Chase, Wellesley, Massachusetts-based Vanguard Renewables was created with the primary goal of transforming what was once considered waste into renewable energy to power homes, businesses and communities.

Working directly with food manufacturers and other organic waste producers from across the food and beverage spectrum, the renewable energy company’s projects have placed an emphasis on recycling organic waste that would have previously ended up in a landfill.

With seven operating facilities located across the Northeast, Vanguard Renewables collects inedible or unusable food waste, along with other organics, which are delivered to the company’s farm-powered anaerobic digestors. From there, the material is combined with farm manure in a sealed biodigester tank, where it is then converted into biogas.

“All of our projects are done through anaerobic digestion (AD),” says Hanselman, the company’s co-founder and CEO. “We take the organic matter, put it into these huge, million-gallon hot pots and cook that product for 30 days. While we do that, the naturally occurring microorganisms that are in the gut flora of the cow manure eat the food waste and emit methane.”

The resulting biogas is then cleaned to produce energy in the form of renewable natural gas for heating and cooling or compressed natural gas (CNG) for vehicles. It can also be converted into renewable electricity.

According to the company, the remaining liquid digestate creates a low-carbon fertilizer that supports regenerative agriculture practice and reduces farm dependence on chemical fertilizers.

GOING THE EXTRA MILE

Although Vanguard’s AD facilities have helped establish the company as a national leader in the development of organic waste-to-energy projects in the U.S., Hanselman says the company eventually identified a demand for more comprehensive recycling operations.

“When we started the company, we thought we just needed to run the anaerobic digesters on the farms. And then it turned out that we really needed to help perform all the logistics, as well as the hauling and dispatching of the food waste,” Hanselman says. “More and more of what we were hearing from customers was that they didn’t want to deal with separating the food waste and removing contaminants. They wanted [someone to provide] all of that.”

"[Our customers] wanted one vendor who would handle all the organic matter. … So, the ORF turned out to be a wonderful step in opening and broadening our appetite, and our ability to consume any organic waste regardless of what form it was delivered to us.” –John Hanselman, co-founder and CEO, Vanguard Renewables

Faced with growing pressure from food waste producers to offer a one-stop shop for organics processing, the company broadened its portfolio with the opening of an organics recycling facility (ORF) in December 2020. The advanced facility in Agawam, Massachusetts, is designed to depackage and process expired goods, off-spec batches or unsafe to eat food and beverage products.

“[Our customers] wanted one vendor who would handle all the organic matter, both to have them in compliance if they were in a state that had a landfill diversion ordinance or if they had a really strong mission statement and commitment to climate reduction and decarbonization,” Hanselman says. “So, the ORF turned out to be a wonderful step in opening and broadening our appetite, and our ability to consume any organic waste regardless of what form it was delivered to us.”

According to Ryan Harb, senior organics market manager for Vanguard, the new depackaging facility has solved a significant need within the industry.

“We opened up this depackaging facility because there’s a lot of food waste and beverage waste out there that is still in its packaging and can’t be sold to consumers. Because [this packaged food] can’t go to a digester or compost facility, it’s getting landfilled or incinerated. So, having this facility is that other option and really helps Vanguard be more vertically integrated,” he says.

Photos provided by Vanguard Renewables

EXTRACTING ORGANIC WASTE

Currently, the facility is permitted to process up to 250 tons of organics per day. Harb says the material coming in can range from beer cans to bakery items, with the facility seeking to recycle any organic matter it can.

“Any organic matter out there that can make renewable energy, we want it,” he says. “We can take it and we can put it to really good use for society. So, send everything our way and we can clean it up and use it for a really good use.”

In order to handle the diverse range of materials the facility comes in contact with, Vanguard uses a series of processes to separate the organics from its packaging.

“The thing that’s really interesting about the depackaging [system] is that it’s basically a big squishing machine,” Hanselman says.

The process begins on a walking floor that allows facility personnel to visually inspect the incoming material. Following the inspections, the material continues on to a series of augurs that are meant to squeeze and move organic material out the sides while leaving inorganics, such as plastics, cardboard and aluminum, in the middle of the system.

The remaining organic material then passes through exterior screens, where appropriate sized fractions are dropped into a containment vessel that is shipped to the company’s anaerobic digesters.

“[The system] we have is just one mechanical step after another,” says Hanselman. “The first step is basically twin screen augers, so it’s kind of like a sausage maker. As material is fed into the system, it’s squishing the organics outside and then it goes into a hammermill.”

The Agawam facility uses a Mega Thor Turbo Separator manufactured by New Prague, Minnesota-based Scott Equipment Co. for its hammermill. The 45,000-pound preprocessing, depackaging and separation system consists of a series of hammers that are tasked with squeezing the material even further.

“The goal of the depackaging facility is to not shatter the plastics or aluminum,” Hanselman says.

“We want to be able to recycle as much as possible. If you shatter it, you get lots of little fragments and shards, so the hammermill acts like a massaging machine. You’re really just trying to squeeze and get the package open. We hope that we open that package in the augers, and now with the hammermill we’re trying to push as much of that material through the screens and out into our collection bins [as we can].”

CLOSING THE LOOP

The organics slurry is stored in tanks and distributed to Vanguard’s farm-based anaerobic digesters daily, where it is extracted for natural gas or biogas to make renewable electricity.

The resulting energy has been used to power nearby schools, a local creamery, and Middlebury College in Vermont, to name a few examples.

“Middleburry College has actually decarbonized their entire campus by only using our renewable natural gas, which is super exciting and emblematic of what we’d like to see more and more of, which is that closed loop cycle,” says Hanselman. “We can take food from the college, we can take food from the local creameries in Vermont, we can take all of that, make renewable natural gas and send it back. That’s the closed loop system, and it works really well.”

Hanselman says Vanguard’s ultimate goal is to be in every major metro area in the U.S. within the next five years.

“Every manufacturing facility and every institution in the U.S. has unusable food waste. There’s really no part of the country that shouldn’t have [organics recycling infrastructure],” he says. “There’s been a wonderful effort to reduce the amount of food waste [that is sent to landfill], but there is an endemic percentage of food that loses temperature, gets contaminated or becomes unsafe for human consumption.”

“If you look at Europe, for example, the proliferation of food waste recycling is like second nature over there. They would never even think of throwing away a half-eaten piece of pizza or something. They would always make sure that it gets to an organics recycling bin, and that’s aspirational. … That’s something that we would love to see [in the U.S.] in the next 10 or 20 years.”

While the Agawam site is Vanguard’s first depackaging facility, the company already has aspirations to roll out similar infrastructure across the country.

“One of the biggest shortcomings in this country right now is there’s not enough of these [facilities], and there’s a lot of food and beverage waste out there. So, we’re really trying to get ahead of that by building [more depackaging facilities] and do something good with [this waste], which is creating that renewable energy and low-carbon fertilizer,” says Harb.

The author is the assistant editor of Waste Today and can be reached at hrischar@gie.net.

Denali Water Solutions acquires Organix Recycling

Denali Water Solutions LLC, Russellville, Arkansas, announced that it has signed a definitive agreement to acquire Organix Recycling LLC. According to Denali, Organix is the largest preconsumer food waste collector and recycler in the United States.

Organix, based in Mokena, Illinois, provides food waste management solutions through which collected food waste is converted into livestock feed, compost and green energy products like biogas.

The financial terms of the transaction were not disclosed.

“Our purpose is to make the world a better place by handling waste responsibly. Bringing the Organix team onboard at Denali supports our goal to expand and diversify our offering with the leading sustainable waste management services in every vertical across the United States,” Andy McNeill, CEO of Denali Water Solutions, says. “Like Organix, we’ve built a culture centered on growth, development and sustainability, and we look forward to welcoming the Organix team to the Denali family.”

Meridian Waste acquires Ace Environmental Holdings

Meridian Waste, Charlotte, North Carolina, announced Feb. 5 that it has closed on the purchase of Greer, South Carolina-based Ace Environmental Holdings LLC.

The acquisition, which marked Meridian’s second acquisition in the greater Greenville, South Carolina, marketplace in a week after the announced purchase of Sunrise Sanitation, will help densify hauling operations in the company’s seven state operational footprint, Meridian Waste says. Terms of the deal were not disclosed.

The Ace Environmental acquisition marks Meridian Waste’s 15th acquisition since the company transitioned to private stock under the ownership of Jacksonville Beach, Florida-based Warren Equity Partners (WEP) in April 2018.

The acquired assets from Ace Environmental Holdings LLC include a construction and demolition debris (C&D) transfer station in Pelzer, South Carolina, and a hauling facility located in Greer that services residential, commercial and governmental contracts in the Greer, Greenville and Spartanburg markets.

The Greer location will serve as the primary hauling company for Meridian Waste, housing the rolling stock and administrative functions of the combined companies. Former Ace Environmental Holdings company owner Steve Serafino and employees of the organization have transitioned to the Meridian Waste team upon closing of the acquisition.

“Entering the South Carolina market with two back-to-back acquisitions ensures that Meridian Waste is a strong player with immediate scale, a strong operating platform, a valuable transfer station, significant synergies and route densities,” Meridian Waste CEO Walter “Wally” Hall says. “We continue to expand our Southeastern footprint in fast-growing markets and look forward to servicing Greenville residents and businesses.”

“The decision to join with the team at Meridian Waste was a natural fit for Ace Environmental,” Serafino says. “Wally and his leadership group have a proven track record of success within the garbage industry. They are focused on issues that matter most, including strategic growth, quality service delivery, a strong environmental record and safe operations. Together, we are in a position to offer the Greenville marketplace strong competition within the solid waste sector. We continue to deliver upon our promise of bringing environmental and financial value to our customers, our employees and our communities.”

EREF releases analysis on national landfill tipping fees for 2020

The Environmental Research & Education Foundation (EREF) released its “Analysis of MSW Landfill Tipping Fees: 2020” report Jan. 29. In the 2020 report, EREF obtained tipping fee information from 439 municipal solid waste (MSW) landfills across the U.S.

• 12 percent were large (i.e., accepting more than 390,000 tons per year);
• 46 percent were medium (i.e., accepting between 390,000 and 65,000 tons per year); and
• 42 percent were small (i.e., accepting less than 65,000 tons per year).

Of the landfills analyzed, the small landfills averaged 26,480 tons of incoming waste per year, medium landfills averaged 166,516 incoming tons per year, and large landfills averaged 809,455 incoming tons per year.

Small landfills accounted for the highest tipping fees for MSW ($55.72 per ton) compared with medium landfills ($50.87 per ton) and large landfills ($53.43 per ton). The average MSW tipping fee across the country was $53.72 per ton, which was a 3 percent decrease from 2019, when the average was $55.36 per ton.

Just as MSW tip fees fluctuated depending on the size of the landfill, they also fluctuated based on where the facility was located.

• The average fee in the Pacific region was $72.03. This included Alaska ($142.33), Arizona ($44.89), California ($58.48), Hawaii ($114.33), Idaho ($59.02), Nevada ($39.90), Oregon ($71.53) and Washington ($95.99).
• The average fee in the Northeast region was $68.69. This included Connecticut (no active landfills in state), Delaware ($85), Maine ($75.21), Maryland ($66.73), Massachusetts (not reported), New Hampshire ($74.34), New Jersey ($78.80), New York ($71.71), Pennsylvania ($73.45), Rhode Island ($115), Vermont ($101.95), Virginia ($53.43) and West Virginia ($54.66).
• The average fee in the Mountains/Plains region was $47.83. This included Colorado ($58.42), Montana ($32.06), North Dakota ($48), South Dakota ($51.22), Utah ($33.80) and Wyoming ($57.64).
• The average fee in the Midwest region was $47.85. This included Illinois ($51.71), Indiana ($36.27), Iowa ($47.07), Kansas ($42.79), Michigan ($42.77), Minnesota ($57.78), Missouri ($67.91), Nebraska ($41.47), Ohio ($45.39) and Wisconsin ($61).
• The average fee in the Southeast region was $46.26. This included Alabama ($32.93), Florida ($56.51), Georgia ($47.88), Kentucky ($36.32), Mississippi ($30.36), North Carolina ($45.97), South Carolina ($45.91) and Tennessee ($51.53).
• The average fee in the South Central region was $39.66. This included Arkansas ($30.53), Louisiana ($37.53), New Mexico ($38.20), Oklahoma ($44.76) and Texas ($42.22).

From 2019 to 2020, the average tip fee fell by $1 in the Pacific, increased by $2.16 in the Northeast, fell by $2.88 in the Mountains/Plains and by $1.02 in the Midwest, increased by $1.01 in the Southeast and fell by $1.26 in the South Central region.

Despite the mixed bag in increases and decreases year over year, fees clearly have been trending upward in recent years. From 2016 to 2020, average year-over-year fees have increased by 4.4 percent in both the Pacific and Northeast, 2.7 percent in the Mountains/Plains, 5.6 percent in the Midwest, 1.1 percent in the Southeast and 2.82 percent in the South Central region.

In addition to collecting MSW tip fee data, EREF also collected information relating to construction and demolition (C&D) wastes deposited at MSW landfills.

According to EREF, C&D waste is accepted at MSW landfills in 41 states and comprises roughly 12 percent of the landfilled stream. Of the 437 landfills surveyed, 277 had a specified gate rate for C&D materials, though the difference was largely negligible on average. The national average tip fee for C&D waste was $52.67. Fifty-eight percent of landfills set the same tip fees for MSW and C&D waste, C&D tip fees were lower than MSW at 23 percent of sites, and C&D tip fees were higher than MSW at 19 percent of the landfills.

In summarizing the entire subset of data, the report’s authors conclude regression analysis doesn’t show a correlation between higher population density and higher landfill tip fees.

“A regression analysis on all tip fees collected showed a limited relationship between tip fees and population density, suggesting that the wide variation in fees is not necessarily associated with population density,” the report states. “An additional regression analysis of tip fees based on population alone showed no relationship between tip fees and total population. These mixed results suggest that greater population density and the associated increase in waste generation has a minor impact on tip fees, and factors such as interstate transport, local regulations and policies, and public/private status of the landfill might have greater influence.”