Control Philosophy

Cooling Tower Blowdown Water Recycle On Site Changi Airport T4 & NTU

1) Feed and Permeate Water Quality Parameters During Pilot Stage

- The 3E-NF60 membrane achieves a turbidity removal rate of over 98%.
- It reduces hardness by 40-50%, effectively minimizing scaling and corrosion risks in cooling systems.
- The membrane demonstrates strong CODcr retention, with an average removal rate exceeding 50%, significantly lowering organic pollutant content.

2) Operating Cost

During the period from January 20 to January 24, 2025 (5 days), the total power consumption was 13.92 kWh. The system operated under the following conditions:

- - Operating Pressure: 3 bar
  - Daily Runtime: ˜8 hours
  - Permeate Production: 12.0 m³/day (excluding backwash, only air scouring)

The electricity cost per cubic meter of produced water is calculated as:

The estimated chemical cost is 0.04 SGD/m³

The total cost per cubic meter of produced water: 0.253 + 0.04 = 0.257 SGD

Comparing Singapore’s current water price (2.94 SGD/m³) with the treatment cost of the 3ENF-60 nanofiltration (NF) membrane (0.257 SGD/m³), the economic benefits are evident. By enabling water reuse at just 10% of municipal water costs, the 3ENF-60 NF membrane effectively converts low-quality cooling tower blowdown into a stable and reliable water source for industrial cooling.

For an industrial cooling system processing 100,000 m³ of water annually, this translates into potential water savings of 250,500 SGD per year, significantly reducing operational expenses and shortening the investment payback period to just 2-3 years.

Furthermore, the 3ENF-60 NF membrane ensures compliance with Singapore’s stringent water quality standards (SS <5 mg/L, COD <30 mg/L), supporting businesses in establishing a sustainable water cycle that integrates water conservation, cost reduction, and regulatory compliance. This makes it an ideal solution for water-intensive industries such as electronics and chemicals.