AASP

The Advanced Activated Sludge Process (AASP) represents the next evolution of conventional activated sludge technology, achieving BOD/COD removal >93%, TSS removal >96%, and ammonia removal >88% in footprints 30-50% smaller than conventional systems. By incorporating step-feed configurations, tapered aeration profiles, selector zones for filamentous bulking control, and real-time DO optimization (maintaining precise 1.5-2.0 mg/L setpoints), AASP delivers superior treatment performance while reducing energy consumption by 18-28% through intelligent blower control and high-efficiency fine bubble diffusers (SOTE 28-35%).

AASP systems are engineered to handle volumetric loading rates of 0.5-1.0 kg BOD/m³/day (vs. 0.3-0.5 kg/m³/day conventional), with F/M ratios of 0.2-0.4 kg BOD/kg MLSS/day and hydraulic retention times of 6-12 hours. Operating at optimized MLSS concentrations of 3,000-4,500 mg/L with SRT 12-20 days, the process maintains a carefully balanced microbial ecosystem including nitrifiers, denitrifiers, and phosphorus-accumulating organisms. Enhanced clarification with polymer-assisted settling achieves surface overflow rates of 30-40 m³/m²/day (vs. 20-25 conventional), enabling compact secondary clarifier designs that further reduce total plant footprint by 25-40%.

Spans Envirotech designs AASP installations from 100 KLD to 200 MLD capacities, tailored to each client's specific COD:BOD:N:P ratios, temperature ranges (15-35°C optimal), pH variations (6.5-8.5), and discharge requirements. Energy consumption typically ranges from 0.5-0.9 kWh/m³ treated with sludge production of 0.35-0.55 kg TSS/kg BOD removed—20% lower than conventional systems due to extended SRT and optimized wasting strategies. The technology is equally effective for greenfield municipal treatment plants handling domestic sewage and for upgrading existing industrial ETPs treating food processing, pharmaceutical, or chemical manufacturing wastewaters. CAPEX savings of 15-30% and OPEX reductions of 20-35% make AASP highly cost-competitive while delivering compliance with the most stringent discharge standards (BOD <10 mg/L, TSS <10 mg/L achievable).