3E Memtech has successfully demonstrated the feasibility of recycling cooling tower blowdown water on-site at Changi Airport Terminal 4 and Nanyang Technological University (NTU). This initiative, powered by the 3E-NF60 nanofiltration (NF) membrane, showcases significant water savings, operational cost reduction, and environmental benefits.
Pilot Stage Performance: Water Quality Improvement
During the pilot phase, water quality parameters were closely monitored, and the 3E-NF60 membrane exhibited exceptional purification capabilities:
- Turbidity removal: Over 98%, ensuring crystal-clear water quality.
- Hardness reduction: Between 40-50%, minimizing scaling and corrosion risks in cooling systems.
- CODcr retention: Exceeding 50%, significantly reducing organic pollutants.
Cost-Effective Operations
The system was evaluated for five days (January 20-24, 2025) under the following conditions:
- Operating pressure: 3 bar
- Daily runtime: ~8 hours
- Permeate production: 12.0 m³/day (excluding backwash, only air scouring)
- Total power consumption: 13.92 kWh
The electricity cost per cubic meter of recycled water was calculated as 0.253 SGD, while the estimated chemical cost was 0.04 SGD/m³, bringing the total cost to 0.257 SGD/m³.
Significant Cost Savings and Sustainability
Compared to Singapore’s current municipal water price of 2.94 SGD/m³, the 3E-NF60 NF process operates at just 10% of the cost. This makes it a highly economical and sustainable alternative, converting low-quality cooling tower blowdown into a stable and reusable water source.
The recycled water meets Singapore’s strict water quality standards (SS <5 mg/L, COD <30 mg/L), ensuring regulatory compliance while enabling industries to achieve substantial water savings and cost reductions.
Ideal Solution for Water-Intensive Industries
The 3E-NF60 NF membrane technology is particularly well-suited for water-intensive sectors such as electronics and chemical manufacturing, where efficient water recycling is essential.
This breakthrough in cooling tower blowdown water recycling underscores 3E Memtech’s commitment to advancing sustainable water management solutions for industrial applications.
