• • The 0.1 mm swinging ultra-fine screen achieved an SS removal efficiency of 89.3% at a pilot scale of 1000 m³/d, compared to 57.4% for conventional pretreatment, reducing fine grit load to downstream biological systems by over 30 percentage points.
• • COD removal was only 9.5% (vs. 28.6% conventional), yielding a carbon source retention of 93%, which is critical for maintaining influent COD/N ratios for biological nutrient removal.
• • Particle size analysis showed near-complete retention of particles >0.1 mm and >98% removal for the 0.075–0.1 mm fraction, directly addressing the 33–73 μm grit fraction that typically accumulates in aeration tanks.
• • The device exhibited stable performance under fluctuating COD and SS conditions, with removal efficiencies varying by less than 27% over a 30-day operation, confirming its robustness for real-world influent variability.