Controlling Biofouling in Reverse Osmosis Systems treating Surface Water: optimizing coagulation pretreatment for nutrient removal
- Persons involved: Vanida Salgado Ismodes (PhD Candidate), Maria Kennedy (IHE, promotor), Walter van der Meer (promotor), Sergio Salinas (IHE supervisor), Antoine Kemperman (supervisor), Franca Kramer (Dunea supervisor)
- Duration: 2023-2026
- Funding: by the European Union (MAR2PROTECT)
Introduction
Water scarcity is a growing concern globally, caused by factors like pollution and climate change and The Netherlands, is not exempt from this challenge. Dunea, a drinking water company supplying 1.4 million people in South Holland, foresees future drinking water shortages due to population growth and climate impacts. To address this, Dunea is investigating new water sources for drinking water production, including Lake Valkenburg. However, surface water usually requires extensive treatment (including reverse osmosis membrane technology) due to contaminants and anthropogenic substances which are discharged directly and indirectly into surface water bodies.
The high natural organic matter concentration (NOM as DOC: 9-14 mg/L) and high seasonal variation in Valkenburg Lake requires a multi-stage pre-treatment system before using the water for drinking or infiltration purposes, otherwise, the high organic matter content could lead to particulate and biological fouling in membrane systems or physical and biological clogging on the infiltration sites.
Keywords
Particulate fouling, biofouling, biological growth potential, organic matter, RO pretreatment.
Research goals
This research aims to: Assess the effectiveness of the pre-treatment lines (coagulation/flocculation/DAF/RSF and coagulation/flocculation/DAF/UF) at pilot scale, evaluating the reduction of particulate matter, bacterial growth potential and organic matter to guarantee high-quality water for reverse osmosis (RO) and infiltration and to understand which nutrients (consumed during bacterial growth) and which bacterial communities are responsible for biofouling in RO and during infiltration. In addition, as the method used to measure bacterial growth potential based on ATP (adenosine triphosphate) was developed for seawater, further development might be needed for surface water.