No Lego in my Effluent Please - Danish Perspective on Microplastics

The microplastic content of the inlet and effluent of two Danish wastewater treatment plants was quantified and chemically analyzed, using an automated method, based on Raman spectroscopy. The results demonstrate retention rates for microplastics of at least 99 %. Filtration of inlet water with a belt filter in a pilot scale facility was investigated as an alternate means of removing microplastics. The developed spectroscopic method was also used to quantify and identify the types of microplastics present before and after filtration and demonstrated a filter retention rate of at least 99 %. Controlled addition of fluorescent microplastics to the inlet water in the pilot scale experiment also demonstrated and verified a filter retention rate of least 99 %.