Biorefining from waste plastics, algae

By Bryan Sims | October 13, 2011

Sean Arnold, chief operating officer for Cleveland, Ohio-based Vadxx Energy and Lawrence Walmsley, CEO of New York-based Culture Fuels Inc. discussed how waste plastics and algae are viable feedstock for the production of green fuels, chemicals and products at BBI International’s Northeast Biomass Conference & Trade Show in Pittsburgh this week.

Arnold explained how his company employs a proprietary thermal depolymerization technology that’s capable of converting recyclable and nonrecyclable waste plastics into a light sweet synthetic crude oil, natural gas, recovered metals and char at its R&D and pilot facility in Akron, Ohio. In addition to waste polymers, Arnold said the company has a diverse waste feedstock stream and signed deals to use scrap tires, medical waste, used industrial solvents and auto shredder residue—the waste material after industrial appliances and automobile components have been shredded after the metal has been removed.

“Out of all those different feedstocks, auto shredder is the highest volume,” Arnold said. “There’s no shortage of this stuff out there.”

According to Arnold, Vadxx has been able to convert all the different grades of plastic based on varying dioxin levels into oil that has lower sulfur content than that of any naturally occurring oil, noting that the company’s oil is light with API gravities between 35 and 45 degrees. Vadxx has an agreement in place to sell its crude oil to Houston-based energy firm RB Products Inc. where it will be further refined into gasoline and other value-added fuels and chemicals. Gas produced by the Vadxx process is converted to electricity to power the company’s production facilities, adding that the gas is actually a hydrocarbon gas that has less Btu content than natural gas, “but it’s enough to do the job for us,” Arnold said. The char that is left after the process, according to Arnold, will be marketed as a saleable commodity to be used in road construction applications.

“I think there are a lot of similar-sounding efforts out there…there’s pyrolysis, thermal depolymerization, gasification and so forth,” he added, “but I think at the end of the day a viable business like this is all about taking something as an input and making it higher value as an output, and making sure that the cost of doing so is less than the gap between those two.”

Along with joint venture partner Greenstar Recycling, Vadxx is developing a commercial-scale plastic-to-oil production facility co-located with a Greenstar material recycling facility in Akron. The facility, anticipated to come online late next year, will be designed to process more than two tons of waste material per hour, or approximately 10,000 to 14,000 tons annually, into 80,000 barrels of oil a year. Two additional commercial plants are in the planning stages that convert medical waste and scrap tire into synthetic crude oil, which are targeted to begin operations in Cleveland by 2013.

Akros Equipment Co., a joint venture between Vadxx and Weingart Manufacturing LLC, will design, manufacture and install Vadxx’s first crude oil production and all subsequent commercial units. Vadxx will own and operate all of the commercial facilities it brings online, according to Arnold.

“When we get this plant up and running and if we make crude oil that the market likes, we think we will not be market-constrained on the outbound side,” Arnold said. “On the inbound side, we get calls from all over the world telling us they’re sitting on a mountain of waste material they want to give us. We’re only in the pilot stage right now. We really believe the market is just huge and the infrastructure already exists for us to be successful.”

Walmsley described how his company is harnessing the inherent benefits found in two of the predominant algae technologies used today—open pond and photobioreactor technology—and developing a low-cost, highly productive hybrid algae cultivation technology platform, trademarked FloatAlgae, that’s capable of cultivating algae strains irrespective of the strain and final product market.

“It’s a floating closed photobioreactor that floats on an open pond,” Walmsley said. “The algae is actually inside the reactor. There’s an integrated aeration system that gets in the carbon dioxide that feeds the reactor.”

In addition to its low-capital profile, Walmsley highlighted additional benefits of the FloatAlgae technology, such as improved thermal control, higher biomass density due to low dewatering costs, reduced propensity of contamination, and the technology is highly scalable he said.

Founded in 2010, Culture Fuels has been conducting testing on the FloatAlgae system at its pilot facility in Florida using selected strains including corporate strains by other integrated companies in the sector. Walmsley said the company is in the middle of fundraising to expand the facility.

“This technology is an enabler for the industry and it allows for the acceleration of the commercialization of this sector,” Walmsley said.