Performance of filters applied for removal of microplastics from water – testing methodology

Abstract

The separation of microplastics from water using the filtration process was studied in this work. The deep-bed filter media were made of polypropylene using the melt-blown technique. The separation performance of these filters was compared to the pleated cellulose elements (surface filtration) for the prepared suspension of fragmented polystyrene particles. No pretreatment nor additives to enhance the separation process were applied upstream the filtration unit. With the increased filter efficiency (rating of depth filters ranging from 20 to 5 µ), the cut-off dimeter of removed microplastic also decreased. The experiments confirmed that deep bed filtration is capable to remove efficiently very fine microplastic particles (as small as 1 µ), while maintaining relatively low pressure drop. The capacity of the deep bed filter will guarantee relatively long operation time for suspensions having a low concentration of MPs, however in real process this will probably be predominantly affected by the simultaneous deposition of other solid contaminants present in the water.