QUA's Q-SEP Ultrafiltration Technology Recycles Wastewater for Cooling Tower Make-Up Water in Leading Zinc-Lead-Silver Smelter Complex
| Challenge: | Integrating an ultrafiltration (UF) unit to enhance wastewater treatment efficiency for reverse osmosis (RO) feed compatibility, targeting an SDI of less than 3. |
| Solution: | QUA Q-SEP® 8012 model was selected for its low-pressure operation and ease of integration, meeting the stringent water quality requirements. |
| Result: | Since integration, the UF system has operated flawlessly, producing water with turbidity between 0.1 to 0.2 NTU, maintaining an SDI below 3, and achieving zero liquid discharge with optimized energy use. |
This project demonstrates the integration of cost-effective and efficient advanced membrane technology for recycling wastewater into cooling tower make-up water at a leading Zinc-Lead-Silver smelter complex to meet stringent water quality standards.
QUA's Q-SEP Ultrafiltration Membranes
Challenge
As a leading Zinc-Lead-Silver producer with an existing Effluent Treatment Plant (ETP) capacity of roughly 800,000 gallons per day (approximately 3,000 cubic meters per day), our client faced a challenge in optimizing wastewater treatment efficiency.
An ultrafiltration (UF) unit was integrated to enhance the treatment efficiency of wastewater before it is supplied to the reverse osmosis (RO) feed. This initiative was driven by the goal of producing water with a Silt Density Index (SDI) of less than 3 to ensure that the treated water meets the stringent quality requirements necessary for compatibility with RO membranes.
Solution
The QUA solution was chosen because it is cost-effective and meets and exceeds the treated water quality requirements for the RO feed water. The decision-making process included capital investments, space requirements, intended flux, and membrane surface area. Ultimately, the client selected the Q-SEP® 8012 model for its low-pressure operation and ease of integration following secondary treatment.
Plant Scheme
Membrane System Design
Results
The UF system has been operational without issues since its implementation in September 2022. The product water is remarkably clear, with turbidity values between 0.1 to 0.2 NTU, and the SDI has remained below 3. The transmembrane pressure (TMP) has been kept below 0.5 kg/m3, reducing energy consumption. The system has also maintained a steady permeate flow rate of 71 m/hr, demonstrating reliable and efficient performance without compromising total output. The RO permeate is further used for cooling tower makeup water application, and the system further achieves zero liquid discharge through a series of operations.