Over the past decades, global plastic production and consumption have witnessed a meteoric rise. Plastic is durable, easy to produce, lightweight, unbreakable, odourless, and chemically resistant. Its low manufacturing cost and durability are the two main factors responsible for the industry’s rapid growth. A so-called wonder product of the twentieth century, this entity is gradually choking our environment and polluting our mountain ranges and seas.
Single-use plastic items have caused a lot of damage to the environment and there’s an urgent need to collectively curb its usage, monitor its disposal, and, if possible, avoid using it altogether. Some plastic is naturally degradable, with the timing for this ranging from years to centuries. Yet in many cases, the products include toxins that themselves are more resistant. In all cases, however, waste is a product of use, therefore production, driven by demand.
Before combat can even begin, militaries start generating waste. Disposing of refuse, such as wrappers, containers, and disused packaging, is a problem at every stage of the life cycle. It takes energy to ship the packaging into a country, it requires dedicated resources to get rid of it, and improper disposal can leave long-lasting damage on the environment and on people who breathe the fumes from burn pits.
Common military practice is to carry out or burn in place things such as empty water bottles, food packaging and human waste. Incinerators and burn pits, which were for years the default waste disposal method of the US military in Afghanistan, come with health risks in the form of hazardous byproducts, durable ground contamination, and the additional risk of light; running an incinerator at night means illuminating part of a base, allowing hostile forces to better see their targets.
DARPA’s ReSource program
DARPA’s ReSource program calls for a portable, self-contained system that can quickly convert energy-dense waste into a useful substance to support expeditionary operations and stabilization missions. This solution can solve waste logistical challenges while providing a stopgap for resupply of critical materials, which could mean the difference between life and death in the field.
Launched in 2021, DARPA’s ReSource program aims to revolutionize how the military procures critical supplies on the battlefield by engineering self-contained, integrated systems that rapidly produce large quantities of supplies from feedstock collected on-site.
Military logistic support has a large human cost in contested environments with no ability to create valuable materials when and where needed. DARPA’s ReSource program aims to revolutionize how the military procures critical supplies on the battlefield by engineering self-contained, integrated systems that rapidly produce large quantities of supplies from feedstock collected on-site.
Envisioned on-demand products include lubricants, adhesives, tactical fibers, potable water, and edible macronutrients. Developed technologies will function simply, reliably, and needing limited servicing in isolated environments. If successful, warfighters will be able to turn forage wastes into lubricants and nutrition, supporting independent expeditionary units and Humanitarian Assistance and Disaster Relief (HADR) stabilization operations.
Performer teams are tasked with developing systems to break down mixed waste, including common plastics, reformulate the waste at the molecular level into strategic materials and chemicals, and recover purified usable products such as oils, lubricants (POLs), and edible macronutrients. The program is now entering its second phase.
ReSource performers will work toward producing a system that will pre-treat and breakdown mixed waste, including recalcitrant carbon-rich polymers like those in common plastics, reform and assemble upgradeable organic molecules into strategic materials and chemicals, and recover purified usable products. The goal is to provide a versatile, operationally relevant, durable system that converts single-use packaging, and other waste, into strategic and critical materials. ReSource will pursue technologies that support this DoD objective by delivering a cross-scale approach for warfighter support extending mission duration and expanding operational flexibility.
In the first phase, teams from Battelle, Iowa State University (ISU), Massachusetts Institute of Technology (MIT), and Michigan Technological University (MTU), in addition to government partners, successfully established proof-of-concept studies toward the invention of integrated novel waste conversion processes.
The ReSource program was first announced in 2019, and in 2020 the team from Michigan Technological University described their plan to turn plastic into protein powder using bacteria.
“Our project is trying to find ways to convert waste plastic into protein powder or nutritional supplements and lubricants,” Steve Techtmann, assistant professor of biological sciences at Michigan Technological University, said in a release. “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, we need an alternative approach.”
Battelle partners at the National Renewable Energy Laboratory (NREL) were featured in Science magazine, and ReSource performers at MTU, along with researchers at the University of Illinois, were awarded the coveted 2021 Future Insight Prize for using microbes to degrade plastic waste and produce protein to generate macronutrients ready for immediate consumption.
DARPA is working with the U.S. Food and Drug Administration to ensure all relevant safety guidelines are adhered to and regulatory standards are met.
DARPA has selected Battelle to develop a prototype system that uses minimal power—approximately the same as a household dishwasher—and runs autonomously with minimal intervention. For the input material, Battelle selected two of the most common plastics—polyethylene and polyethylene terephthalate. Polyethylene is commonly used in milk jugs and food packaging, and polyethylene terephthalate comprises things such as single use water bottles and food trays. The team had the choice of a variety of food, pharmaceutical and chemical outputs and selected gun lubricant because the material is both critical to warfighters in the field.
Battelle’s proposed solution will house and monitor genetically engineered microorganisms in banks of bioreactors to degrade plastic and upgrade it into a useful material. Because bacteria self-replicate, don’t use a lot of power and are shelf-stable for a long time in their dormant phase, they are ideally suited for this type of process. The challenge is to make the bacteria work fast enough.
Bacteria self-replicate, meaning only a small amount of the microorganisms would be needed to start the process. Like the Michigan team, Battelle described the time of biological degradation as the greater obstacle, with an expressed desire to speed the process along. “These processes are very slow in nature. We are working to accelerate these reactions from months to hours,” said Battelle Principal Research Scientist Jake Lilly. “Synthetic biology is all about harnessing and tailoring biology to do atypical processes that are beneficial to mankind.”
“The team had the choice of a variety of food, pharmaceutical and chemical outputs and selected gun lubricant because the material is both critical to warfighters in the field,” said Battelle in a release. Guns are a series of moving parts, and friction that causes a gun jam can be fatal. Converting packaging waste into gun lubricant increases the likelihood that soldiers have what they need on hand, and reduces the amount of lubricant that needs to be shipped to forward bases in the first place.
The project will also rely on the team’s materials science expertise, particularly in polymers, to determine the chemistry needed to prepare waste plastics for microbes to convert one substance into another. Systems engineering capabilities will also be essential to creating a complete and ruggedized system with an intuitive user interface that can be used with little training by any warfighter in the field.
“Part of what makes DARPA special is that we de-risk technologies to enable scientific innovation,” noted Dr. Blake Bextine, ReSource program manager. “All of the teams have passed their Phase I demonstration tests, and I’m looking forward to seeing what they have in store for Phase II.”
In the Phase II, performer teams will build on Phase I accomplishments to develop integrated systems which leverage innovative engineering to function under less optimal conditions, with increased masses of waste to process, and a reduced energy allowance. Possible approaches could include performing pilot tests with simple waste mixtures to prepare for an End-of-Phase demonstration at scale. Results should give a good indication that multiple waste-stream types in a mixture can be converted to upgradable organic intermediate molecules and use these molecules to demonstrate sufficient purity by generating at least one product – food and/or POLs by the end of Phase II.
“There is more energy in the packaging of an MRE (meal, ready-to-eat) than in the MRE itself,” added Bextine. “Through ReSource, we are using science to solve the DoD’s plastic waste dilemma while supporting Humanitarian Assistance and Disaster Relief (HADR) stabilization operations in resource-limited environments.”