Deployment of Recyclable Polycarbonate as Alternative Coarse Media in Dual-media Rapid Filters

Sand and anthracite coal/granular activated carbon are commonly employed in traditional dual-media rapid filters to remove physical impurities present in influents. With increasing emphasis on sustainability, more water treatment facilities worldwide are opting for the use of eco-friendly materials which include recycled crushed glass, wood chips, and coconut shell based carbons. For instance, some filtration facilities of private pools in the United States have adopted recycled glass and obtained high quality effluent. The deployment of eco-friendly filter media in rapid filters deserves attention. In this study, sewed polyester bags which contained recyclable polycarbonate pellets (RPCs) were deployed as an alternative coarse media in a lab-scale dual-media rapid pressure filter setup. By coupling RPCs with sand, the following performance criteria were attained during the experimental runs when compared with the traditional dual-media: (a) similar rate of head loss development while maintaining acceptable effluent quality, and (b) improved clogging distribution within the filter. Life-cycle analysis (LCA) was also carried out with the Gabi Education software to assess the environmental footprint associated with various dual-media combinations. It is hopeful that the obtained LCA results would provide useful insights to industrial decision-makers who wish to improve the company's environmental performance index.