THE Cupang Water Reclamation Facility in Muntinlupa City has just been upgraded with a wastewater treatment system using advanced biological processes to improve water quality and nutrient control.
The facility, operated by Maynilad Water Services Inc., was retrofitted last November with Hitachi’s cutting-edge Pegasus (IFAS) technology. The upgrade can treat up to 46 million liters of wastewater once in full operation.
Nitrogen compounds are a persistent challenge in wastewater treatment. Domestic sewage contains ammonia and other nitrogen forms that, when released into rivers and coastal waters, can trigger eutrophication — which accelerates algal growth, depletes dissolved oxygen, and disrupts aquatic ecosystems — effects that have been widely documented in urbanized watersheds and coastal environments connected to Manila Bay.
To address these concerns, the Cupang facility is integrating an advanced treatment method known as an Integrated Fixed-film Activated Sludge system. Unlike conventional activated sludge processes that rely on freely suspended microorganisms, this approach combines suspended biomass with fixed media that support microbial attachment and growth.
The system uses specially designed pellets containing immobilized nitrifying microorganisms. These pellets create a stable environment where bacteria responsible for nitrification and denitrification can thrive at higher concentrations. Through these biological reactions, ammonia is converted into nitrate and ultimately into inert nitrogen gas, which is safely released into the atmosphere.
Environmental engineers note that nitrogen removal has become one of the most technically demanding aspects of wastewater treatment. Conventional systems often struggle to meet stricter nutrient limits without increasing tank volumes or extending treatment times — both difficult options in land-constrained urban areas.
By intensifying biological activity within existing infrastructure, fixed-film systems can improve treatment performance without significantly expanding a facility’s footprint. This approach is gaining wider adoption in dense cities where population growth continues to increase wastewater volumes.
Aeration, which supplies oxygen to support microbial processes, is one of the most energy-intensive components of wastewater treatment. Advanced biological systems rely on precise control of oxygen levels to ensure that microbial reactions occur efficiently without unnecessary power consumption.
Automated control systems adjust aeration and flow rates in real time, helping operators balance treatment effectiveness with energy efficiency. This integration of sensors, control algorithms, and biological processes reflects a broader shift toward data-driven infrastructure in the water sector.