Phased Activated Sludge System

The AquaPASS® system is a time-managed activated sludge technology that integrates select unit processes into a single biological treatment system.


Optimize treatment of the AquaPASS system with the IntelliPro® Monitoring and Control System

• Monitoring, trending and data analysis
• Energy savings process control
• On-line troubleshooting assistance
• BioAlert™ process notification system


    Aqua MixAir® system provides flexible control of aeration and mixing


    Time-based anoxic intervals promoting exceptional nitrate reduction


    Superior process environment suitable for cold weather climates


    Ideal for a wide range of design flows


    Flexible tank design and equipment options


    Flow-through operation with multi-stage performance


    Concentrated return activated sludge (RAS) provides optimized process environments


    Membrane ready for future expansions


    Load proportioned power savings mode


    Simple and flexible system operation


    Municipal and industrial wastewaters


    Enhanced biological nutrient removal (EBNR)
    - Total nitrogen < 3 mg/l
    - Total phosphorus < 0.6 mg/l


    Water reuse and reclamation


    New plant construction


    Retrofit existing activated sludge systems


    Convert oxidation ditches

AquaPASS® Phases of Operation

The four (4) basic phases of the AquaPASS® operation are described in this narrated 3D animation. Watch Now

Featured Story

Salisbury Retrofits Existing Process with an AquaPASS® System to Comply with the Chesapeake Bay Initiative

The Salisbury Township WWTP in Gap, PA utilized a conventional activated sludge (CAS) system prior to being retrofitted with an AquaPASS Phased Activated Sludge System in May 2008. The upgrade was necessary in order to comply with the Chesapeake Bay Initiative for local impaired waterways, requiring stringent permit limits on effluent Total Nitrogen and Total Phosphorus by 2010.

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