We are increasingly aware of the amount of microfibres – notably microplastics – which are created by washing our clothes and the damage they are doing to marine life. Typically, these microfibres leave our household laundry washing machines and travel to a local waste-water treatment plant (WWTP). The WWTP can capture more than 90% of the microfibres in the sludge, but this still allows large quantities of this pollution to leave the plant in the ‘clean’ effluent water. The majority of the microfibres captured in the sludge may still end up in natural waters as the sludge is frequently spread on fields as fertilizer. The microfibres are then washed off the fields in springtime melt and rain run-off to ditches, creeks, rivers, lakes and eventually the oceans, where they can be ingested by marine life. Microplastics can be ‘burped’ up from the ocean depths to the surface, and then blown out over land, only to return to the ground in ’plastic rain’.
Therefore, it is better to capture these microfibres as they leave the washing machine before they get to the wastewater system. The microfibres captured at home can be put into the household solid waste stream (possibly for recycling), and prevented from reaching natural waters via the waste-water path. A recent study revealed that over 100 mg of microfibres are released from laundering a kilogram of fabric, per washing.
In a proof-of-concept run (see video), a significant amount – close to a cup (250 ml) of packed dried fibres - were captured by draining the wash and rinse water from four loads of laundry through this fabric.
The key to this invention is a fabric made from recycled plastic used in a commercial application which captures microplastics and other particles down to less than 10 microns in size. For comparison, human hair varies from about 20 to 180 microns in diameter. The fabric is reusable indefinitely, only needing to be emptied / cleaned periodically. This innovation creates a practical, low-cost device which can capture laundry microfibres before they get to the wastewater system. This device separates the loose fibres from clothes, does not interfere with washing machine effectiveness, does not trap soap with the clothes, and really captures fibres and microfibres. The container and mounting parts are all conventional hardware, so it can be manufactured via simple methods at low cost.
The size of the market depends on how many households care about the issues of microplastic pollution and the impacts of plastic pollution on the environment and our health. Laundromats and commercial laundries (e.g., in hotels, on cruise ships) might be regulated to require such filtering (probably in a larger version of the device).