Positive aqua solutions-AS™ takes a fresh look at activated sludge systems to overcome the traditional mixing and oxygenation inefficiencies to save time and  energy.



Activated sludge process plants are the most widespread technology in wastewater purification. They can be found in different climate conditions from the Tropics to the Polar Regions, aboard ships and at extreme elevations. Activated sludge systems can treat blackwater, brownwater, greywater, feacal sludge and industrial wastewater as long as the pollutants to be treated are biodegradable. The term refers to a natural suspended aerobic sludge consisting of flocs of active bacteria, which consume and remove aerobically biodegradable organic substances from screened effluent.

Used in a controlled environment nutrients and pollutants can be removed on a much larger scale than would naturally occur in water bodies. The most critical action in the process is the delivery of free oxygen (O2) for bacterial growth. O2 is traditionally provided via mechanical paddle, disc, spray and turbine aerators. These inefficient delivery systems consume approximately 60 to 75 percent of the net power demand for a typical activated sludge wastewater treatment plant.

Pas-AS™ was developed to efficiently deliver this fundamental element and improve process efficiency through thermal destratification. Pas-AS™ innovative 'bottom up' approach provides both favourable vertical thermohaline circulation and surface movement to maximise oxygenation with the minimum of energy input. Pas-AS™ revolutionary design further reduces the treatment plants footprint through the constructing of much deeper selectors. The reduced surface area of the selector produces far less heat exchange, allowing theground temperature to maintain a constant liquid temperature ensuring longer aerobic bacterial survival.