The BioPROTEIN research team demonstrated its project to convert plastics into usable products at the Keweenaw Research Center Wednesday. The pyrolysis unit is used to break down plastics in high heat without oxygen. Garrett Neese/Daily Mining Gazette

FRANKLIN TOWNSHIP — It’s hard enough to break down plastics, famously engineered to be long-lasting. Converting them into usable products, and doing so with limited energy, is “almost an impossible problem,” said Michigan Technological University professor Steven Techtmann.

“I wasn’t sure that we were actually going to be able to do it,” he said to a group of academic and military personnel at the Keweenaw Research Center Wednesday. “It seemed more science fiction than fact. So the fact that we’re here today demonstrating it is pretty exciting.”

On Wednesday, the BioPROTEIN research team displayed portable technology capable of converting plastic waste into valuable resources, such as food, lubricants, fuel and candles.

It includes Techtmann and Tech’s David Shonnard, Rebecca Ong and Jeff Naber, along with Joshua Pearce from Western University and Ting Lu from the University of Illinois-Urbana Champaign.

“Most of these systems that we have right now for recycling are required to be done in the scale of a chemical processing plant,” Techtmann said. “So it’s not something that you can drop into a forward operating base.”

The Defense Advanced Research Projects Agency Biological Technologies Office’s ReSource program is funding the project to reduce military waste. Work began on the $8 million project about four years ago.

Plastic is durable, and not much of it can be recycled conventionally. The wrapper for an MRE actually contains more calories than the food inside it, Techtmann said. The result, Techtmann said, is “there’s a lot of energy that then just gets thrown into the garbage.”

“That poses a problem, especially if you’re in a forward operating setting, because you have to deal with this trash, and so it’s either buried, or in some cases, carted off,” he said. “And so these wastes represent a potential resource, if we can come up with methods to be able to convert them into valuable products.”

The team developed a portable system compact enough to fit in a truck bed. Mixed plastic waste gets broken down into liquids through ammonium hydroxide heated at 220 degrees. The reactor can process about 300 grams of plastic at a time.

Those liquids are then fed to natural and engineered bacteria, which can turn it into more of their cells. The bacterial biomass can be used as a supplement akin to vegemite or protein powder. Testing has shown the product to be non-toxic, Techtmann said.

During testing, the group fed the liquid to microbial communities from a number of sources, including compost from a farm in Hancock.

“We’ve basically been growing and further adapting them in the lab setting, and so at this point, they’re really optimized to be able to go through the process,” said Lindsay Putman, a research assistant professor working on the project.

The solids left over go through pyrolysis, or the breakdown of waste through high heat without oxygen. Through that, they recover waxes, motor oil and fuel, the latter of which can then help power a generator. The rest of the energy for the work can be generated through a stand-alone solar array.

From shredding plastic to the final outputs, the process takes between 24 to 48 hours.

Wednesday’s presentation came ahead of what Techtmann described as the group’s “final exam”: a full-scale demonstration for DARPA held on Thursday.

It’s still at the proof of concept stage, Techtmann said. If all goes well, the systems could be deployed in a few years.

“This is a huge step that we can say it’s working, but there is still some tweaking that needs to be done before it can be in that container and out,” he said.

And the concept could grow from there. Techtmann said the hope is to grow the technology to a commercial or industrial scale. Even at a larger size, the process would take about the same amount of time, he said.

“I think the plastic problem is such a big problem that it’s going to take a lot of solutions, and that technology that we develop I believe can play a role in at least dealing with some of that plastic waste,” he said.