3D-printed water filter uses bacteria to capture microplastics

Dubbed OFlow, the system uses a non-pathogenic bacteria to form a layer of biofilm that can bind to microplastics

Spotted: According to reliable studies, micro-plastics in different forms are now present in almost all water systems in the world, with 83 per cent of tested water samples from metropolitan areas around the world containing microplastics. Now, a team of students at the University of Southampton was runner up in the national Dyson Awards for their design for a water filter that uses bacteria to capture micro-plastics.

Dubbed OFlow, the system uses a non-pathogenic bacteria, called P. flourescens, to form a layer of biofilm that can bind to microplastics. The bacteria are grown on a structure with a large surface area, called a scaffold. The scaffold is itself 3D-printed from a biodegradable material, inoculated with the bacteria and inserted into a bioreactor (a device that grows bacteria). The bioreactor is then integrated into existing water treatment systems. 

The team developing OFlow suggest that their design would work in small to medium-sized water treatment plants. It uses a semi-autonomous design that requires very little additional effort to operate. Because the materials used in the OFlow are biodegradable, the device is aimed towards long term use. In addition, the scaffolds can be easily removed, cleaned and then reused. 

The team were inspired in their efforts by the realisation that current water treatment methods are not adapted to completely filter microplastics from domestic wastewater. According to their Dyson Award entry, they “saw an opportunity to nip microplastic pollution in the bud by removing these unfiltered particles before they enter the ocean. We strive towards a design that assimilates with the current water treatment process to prevent a system overhaul.”

At Springwise, we have seen a number of recent innovations aimed at eliminating various sources of microplastics. These have included a device that collects microplastics shed from car tyres and an after-market washing machine filter that can capture those from clothing.

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