Feasibility assessment of alternative environmentally friendly disinfection technique for reverse osmosis-based desalination process

Abstract

In the seawater reverse osmosis (SWRO) process, the chlorine-based disinfection method poses significant incidental problems, such as producing disinfection by-products and damaging the SWRO membrane surface directly. Chlorine dioxide can control the biofouling layer and relatively stable disinfection approach during the operation. Major two perspective views, such as process stability (water flux and salt rejection) and membrane surface functionality, we evaluated chlorine dioxide feasibility as an alternative disinfection. Standard SWRO performance was evaluated at various operation conditions (inlet pressure and flow rate) using a customized SWRO system. For the stability of the chlorine dioxide disinfection approach, the chemical exposure test was conducted within the concentration and time-variant. While full total 30 days of long-term operation with continuous chlorine dioxide (0.5 mg/L) stripping during the SWRO desalination process, water flux and salt rejection rate maintain 26.7 L.min−1 and 99.7 % respectively.