General Hospital Wastewater Treatment Plant in Manila, Philippines

Project Background

This hospital has 600 beds and generates about 300 m³/day of medical wastewater. The original treatment system could not effectively remove pharmaceutical residues, pathogenic microorganisms, and ammonia nitrogen. The effluent did not meet the Philippines Department of Environment and Natural Resources’ latest discharge standards for healthcare facilities. The hospital is located in the city center with no space for expansion, and the retrofit could not interrupt hospital operations.

MBBR Retrofit Solution

The existing SBR (Sequencing Batch Reactor) was converted into an MBBR system. MBBR Media was added directly into the existing reactor at a 40% filling ratio, retaining the original aeration and mixing equipment. MBBR’s high biomass concentration enabled a significant increase in treatment capacity within the same tank volume. The conversion was carried out without shutdown by implementing a phased, tank‑by‑tank approach.

Retrofit Results

● Ammonia nitrogen reduced from 45 mg/L to below 3 mg/L, removal efficiency 93%.

● COD reduced from 350 mg/L to below 50 mg/L, removal efficiency 86%.

● Pathogen removal (fecal coliforms) reached 99.99%.

● Zero disruption to hospital operations.

● Sludge production decreased by about 55%, reducing hazardous medical waste disposal costs.