SUBICWATER has effectively raised the treatment capacity of its sewage treatment plant in Kalayaan, Subic Bay Freeport by 40% after adopting a superior treatment system.

From 900 cubic meters per day capacity, the facility can now treat 1,500 cubic meters of wastewater after it was upgraded to employ the Sequential Batch Reactor (SBR) technology.

This system is more efficient as the stages of equalization, aeration, and sedimentation are carried out in a single SBR tank on a timed sequence.

Conventional systems, in comparison, bring wastewater to separate tanks for each stage of the treatment cycle. Besides taking up more space, this system requires more energy as the separate components of the STP are constantly running.

The treatment cycle in the new system will start once an SBR tank has collected its full load of wastewater. Once wastewater leaves the SBR tank, it only needs a final dose of chlorine before it is discharged safely to the environment.

While an SBR tank is running, another tank will collect the incoming wastewater.

The upgraded Kalayaan STP, which has three SBR tanks, is now the third largest STP of SUBICWATER in terms of treatment capacity.

The largest at present is the Central Business District (CBD) STP with 5,000 cubic meters per day capacity, followed by the Enron STP with 2,500. Both use the SBR technology.

Overall, SUBICWATER’s six STPs have a total treatment capacity of 10,800 cubic meters per day, or 1.080 million liters per day.