Technological watch

Michigan Tech researchers have been selected for a $7.2 million DARPA cooperative agreement award to turn military plastic waste into protein powder and lubricants.
Researchers will take plastic or mixed waste from military operations and make it into something useful for the military. Often, plastic is the hardest waste to deal with. This project is trying to into protein powder or nutritional supplements and lubricants. The general idea is that plastic is hard to break down using biology because it’s made up of a polymer, and its units are stuck together. To break apart the polymer, some bacteria can do this, but it’s very slow. So, to convert plastic into food quickly, an alternative approach is needed.
7.2 Million Dollar Grant for Project BioPROTEIN
Steve Techtmann, Michigan Technological University, has been selected to receive a Defense Advanced Research Projects Agency (DARPA) cooperative agreement award for $7.2 million over four years to refine a method of chemical and high heat (pyrolysis) deconstruction of plastic waste into protein powder and lubricants.
The project, BioPROTEIN (Biological Plastic Reuse by Olefin and Ester Transforming Engineered Isolates and Natural Consortia), is a collaboration between Michigan Tech and Ting Lu, professor of bioengineering at the University of Illinois at Urbana-Champaign. At Michigan Tech, joining Techtmann are chemical engineers Rebecca Ong and David Shonnard and materials engineer Joshua Pearce.
Design, Recover, Integrate
The four-year project is broken into three phases. During the first phase, the research team will show its proof of concept, that it can turn waste plastic into protein powder and lubricant. They will design and use the separations system to recover 2.5 grams of microbial protein powder.
“There are systems for dealing with plastic where you recycle it. Michigan Tech made one where you take a ” Techtmann said. “Our plan is to put plastic in and turn it into something entirely different on the other side of the box.”
The second phase is to demonstrate the team can put the individual parts together to recover 100 grams of microbial protein powder from culture medium.
In the final phase, the team will turn their “black box” into a field operational unit that can integrate separations into the system and purify kilograms of protein powder at a time from the recovered media. The goal is for the system to be self-sustaining for as long as 28 days, and for it to fit on the back of a truck and use solar energy for power. Additionally, the team will 3D print many of the system components and make these designs open source, making the system affordable in settings beyond the military, such as in disaster relief scenarios.
Break It Down, Build It Up
The first step of the process is to convert plastic into compounds that look somewhat like oil using heat and a reactor that can deconstruct plastic’s polymer chains. The oil-like compound is then fed to a community of oil-eating bacteria Techtmann’s lab has been studying. The bacteria grow very fast on their oily diet, producing more bacterial cells, which are about 85% protein. It’s through this process that the team can convert plastic to protein very quickly.
The researchers envision a system like this: There’s a slot on one side where soldiers will throw in their plastic waste. The waste goes into processing reactors to be broken down by heat and/or chemicals. Once broken down, the byproduct will be fed into a vat with the bacteria, which chew on whatever flows there and grow. The cells are then dried down into a powder that can be used as needed.
By enriching specific amino acids and polyunsaturated fatty acids, researchers hope to increase the nutrient content of the powder and tailor it for military need.
“This is about generating a technology that we can hand off. We’re developing it for the problem of expeditionary military units, but the technology we would come up with could be scaled to get clean water and food to people who need it in disaster relief,” Techtmann said. “It’s a natural outcome of the project to be broader than just in military applications. We’re providing a framework for how we deal with plastic waste in general.”