Photos provided by Atlas Organics

Since its founding in 2015, Spartanburg, South Carolina-based Atlas Organics (Atlas) has worked to revolutionize the composting industry through the development of a comprehensive organics recycling platform.

As a provider of collection, processing and consulting services for more than 1,600 homes and more than 100 organizations across nine cities, the company has seen significant growth since opening its first composting facility just six years ago.

“In 2015, we decided to ... create Atlas Organics. We worked with our first investor to raise $500,000. That helped build our first composting facility, and from there, we started expanding the hauling units,” says Gary Nihart, COO of Atlas Organics. “We [originally] started collecting food waste in upstate South Carolina, [such as in] Asheville [and] Columbia. Since then, we’ve been through several more rounds of funding and we’ve expanded operations into North Carolina, Tennessee, Florida and Texas.”

Currently, Atlas operates a total of six composting facilities and four hauling operations in Greenville, South Carolina; Durham, North Carolina; Indian River, Florida; Tampa, Florida; Memphis, Tennessee; and San Antonia, Texas.

Most of the facilities are managed through public-private partnerships with the municipalities. Under these long-term agreements, Atlas will accept feedstocks that are controlled by the municipality in exchange for a per ton tipping fee. These feedstocks can include yard waste, food waste and biosolids.

Atlas also brings in food waste from its internal hauling division, which operates collections for commercial and residential customers in South Carolina, North Carolina and Tennessee.

“Yard waste and biosolids are typically sourced from different municipalities, usually a city or a county, under a long-term contract,” says Nihart. “We collect food waste from our residential customers [through a doorstep collection program] known as Compost House. We deliver buckets, our customers put the buckets out, we can pick it up and leave [the residents] with an empty bucket.

“We get food waste from our commercial customers as well, [such as] grocery stores, hospitals, restaurants, schools, things of that nature. And then we get our food waste also from industrial customers. These are big food processors which have large amounts of food waste on a large scale, and we collect it.”

THE PROCESS

At the composting facilities, Atlas’ process begins with the grinding of yard waste using horizontal grinders fed by excavators. According to the company, these machines take loose unground municipally collected yard waste and reduce it to a 4- to 6-inch-minus single-ground mulch. This material will act as a carbon source for the composting process.

After the yard waste is processed, it is either added directly to the composting process or mixed with a nitrogen source such as food waste or biosolids at an approximate 50-50 ratio by weight.

“With composting, you need a few ingredients. You need a carbon source. Typically for us this is yard waste. And you need a nitrogen source, which is food waste or biosolids—the green part of yard waste. You need carbon, nitrogen, water and oxygen,” says Nihart.

This material is then transported by wheel loader to the composting system, which is comprised of a series of air blowers and an aeration floor/piping system. This system is known as an Extended Aerated Static Pile (EASP).

"The use of robotics and artificial intelligence in organics is going to allow companies like Atlas Organics to really go after some of the dirtier feedstocks that have contamination.” – Gary Nihart, COO, Atlas Organics

With EASP composting, fresh oxygen is blown into the pile under positive pressure to maintain aerobic conditions throughout the pile, thus eliminating the need for pile turning. This process can accelerate the decomposition of the organic waste material, achieve pathogen reduction requirements and prevent odor generation.

“We use a system of blowers with perforated pipes that are operated by computers, and these blowers are introducing oxygen at various intervals,” says Nihart. “Our piles heat up and get to the thermophilic phase where they’re really hot and there’s a lot of microbial activity breaking down the organic compounds. Then, the piles go through a mesophilic phase where there’re still microbes in there breaking it down, and some fungi get introduced.”

Compared to typical windrow composting operations, Atlas says it avoids using a diesel-powered windrow turner and limits dust generation by not turning the pile. Throughout the process, the material is monitored through various quality control methods including Solvita tests, bulk density tests, temperature monitoring and moisture monitoring through a batching protocol.

Once the material is fully composted, which can take anywhere from 45 to 60 days, it is removed from the composting system and screened to a 3/8- or ¼-inch-minus utilizing a trommel screen.

“We screen it down to a certain size so that it’s got that nice earthy feel to it—it’s not big and chunky. Then, it’s ready for the customer,’ Nihart says.

This material is also lab tested for U.S. Compost Council STA Certification. After the results are analyzed to confirm national and state limits are met, the material is sold into the marketplace.

NEW TECHNOLOGY

In an effort to increase efficiency of its organics processing, Atlas has deployed new technology to better address contamination challenges in current food waste feedstocks at its most recent composting facility in San Antonio.

“The expansion into San Antonio was prompted by the fact that we saw Texas as an underserviced market in the organics industry and specifically saw that the city of San Antonio had larger desires to try to divert residential organics from the landfill,” says Atlas CEO Joseph McMillin. “That came with challenges. So, we’ve worked with the team at the city of San Antonio to develop a unique solution for them to divert that material from the landfill that other processors could not help with.”

According to a release, the city of San Antonio has implemented residential food waste recycling programs but has historically outsourced its services. With Atlas, the city will now have its own composting facility at Nelson Gardens.

The new $10.8 million facility—built in partnership with Apex, North Carolina-based Crowder Construction—uses a one-of-a-kind patent pending presort line developed by Atlas to remove contaminants from the city’s green cart programs.

Atlas worked with new and current vendors, such as Rotochopper, St. Martin, Minnesota; AMP Robotics, Louisville, Colorado; and OEM Sherbrooke, Quebec, Canada, to design the system. Atlas is also utilizing custom control systems at the site to optimize the aerated static pile composting process that was designed by the company’s internal engineering team.

"The expansion into San Antonio was prompted by the fact that we saw Texas as an underserviced market in the organics industry and specifically saw that the city of San Antonio had larger desires to try to divert residential organics from the landfill.” – Joseph McMillin, CEO, Atlas Organics

“To our knowledge, [this facility is] the first time that AI (artificial intelligence) and robotics have been used in a pre-sort facility for organics in North America,” says McMillin. “The goal of the presort facility is to remove contaminants from the organic waste stream prior to processing instead of trying to remove those contaminants after they’ve been through the composting process via vacuums and wind sifters that have historically been attached to the screening process.

“Our thought behind that was that it’s easier to remove the contaminants, such as plastics, when they’re moving in a more whole form than after they’ve been through the grinder and through a 45-day decomposition process and touched by multiple pieces of equipment.”

For McMillin, the biggest issue he sees with managing the incoming organic waste stream is contamination. In order to derive a high-value product, he emphasizes the importance of having a clean feedstock going into the process.

“The use of robotics and artificial intelligence in organics is going to allow companies like Atlas Organics to really go after some of the dirtier feedstocks that have contamination,” says Nihart. “All the different kinds of plastics, metals and things like that can get [into] feedstocks, especially when you’re dealing with food waste. There are feedstocks, historically, the industry has stayed away from just because it’s too hard to deal with. AI allows us to turn those feedstocks into revenue streams and turn it into a valuable soil amendment.”

Atlas currently has another municipality looking into implementing similar technology within the next 12 to 18 months.

“We’re always open to working with other municipalities, specifically ones with green cart programs where contamination is a major factor for them,” says McMillin.

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