Hybrid Wastewater Treatment: Efficiency and Challenges in Microplastic Removal

High Resolution Image Download MS PowerPoint Slide Hybrid treatment trains, integrating complementary physical, biological, and chemical barriers, deliver more robust control of microplastics (MPs) in wastewater treatment plants than conventional single-unit operations. However, fibers and small fragments (20 μm; disc filtration ∼98%; and conventional activated sludge ∼64–98%. These removals are reported on a count basis above study-specific lower size cutoffs (typically ≥ 20 μm). However, hybrid treatments report removals ∼100%, though values vary with detection limits and MP size classes analyzed. Membrane-centric trains (e.g., membrane bioreactor with ultrafiltration) reach nearly complete removal. Chemical–physical hybrid treatments (coagulation–flocculation with membranes; electrocoagulation–electroflotation plus ultrafiltration) can reach ∼100% removal. Ozonation coupled with granular activated carbon sustains ∼92% removal at pilot scale and up to 98% at full scale. Bubble-enhanced flotation exceeds 98% removal for 20–100 μm. Adsorbent-assisted hybrids capture ∼99% of smaller MPs. Despite these gains, fibers and