I-Corps: Microplastic filtration from active waterways

Princeton University, Princeton NJ

Investigators

Abstract

The broader impact/commercial potential of this I-Corps project is the potential development of a portable microplastic measuring and sequestration device. Every year approximately 8 million tons of plastic enter US waterways, of which 80% gets transported in polluted rivers as both macroplastics (above 5 mm in size) and microplastics (below 5 mm in size). Microplastics are rapidly becoming a global concern, as they can easily be ingested, introducing potentially hazardous and carcinogenic additives into the diets of wildlife and humans. Currently, there are no consistent protocols available for the accurate and systematic recording of microplastic pollutant concentrations in water. Furthermore, there is also no existing technology available to sequester microplastics from tributaries, effluent streams, reservoirs, and lakes. This technology could be used by aquatic emissions research organizations and municipal riverkeepers, as it may provide them with a universal tool for microplastic monitoring and sequestration. Additionally, this device can be deployed as part of wastewater and drinking water treatment infrastructure, to potentially remove microplastics from aquatic environments. Finally, this technology could allow extracted microplastic collected from the device to be upcycled and reused, creating a circular economy for microplastic waste. This I-Corps project is based on the development of a proprietary filtration technology with the potential to physically entrap microplastic sediments from active waterways. This technology is uniquely designed to efficiently sequester microplastics from rivers and effluent streams without potentially disrupting local ecosystems. Unlike fine mesh nets that can easily get clogged with algae, slow down river flow, and entrap aquatic wildlife, this device uses a patented ‘artificial root’ biofilter to entrap microplastics. This biofilter is a dense mesh of fibers that physically ensnare sediment in the upper strata of a river’s water column, which is where almost all microplastic is found. When submerged in water, this network hosts bacteria that produce sticky biofilms that can further adhere small aquatic sediments like microplastics. The network, while dense, is uneven and has openings that allow for the transit of small aquatic organisms. Each biofilter is attached to a removable pad, making it easy to swap biofilters once they become saturated. Each pad is housed within a hydrodynamic flotation frame, aimed to allow the device to be deployed in both rivers, streams, and reservoirs. Due to it having no mechanical components, this technology operates passively, requires no electricity, and demands minimal maintenance to operate effectively. This could make the device cheaper to produce, deploy and maintain compared to the existing microplastic filtration systems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.