Experimental investigation and numerical optimization of periodic in situ ozonation to control fouling in ceramic ultrafiltration membranes

• Main Authors: Tagliavini, Matteo, Leow, Shijie, Clement, Jonathan, Galjaard, Gilbert, Snyder, Shane Allen
• Other Authors: Nanyang Environment and Water Research Institute
• Format: Article
• Language: English
• Published: 2024
• Subjects: Engineering::Environmental engineering; Advanced Oxidation Process; Ceramic Membrane
• Online Access: https://hdl.handle.net/10356/173370
• Institution: Nanyang Technological University

The chemical resistance of ceramic membranes opens new frontiers in hybrid membrane-oxidation processes. An example is in situ ozonation, which has been demonstrated to be more effective than preozonation to reduce ceramic membrane fouling. This work explores the possibility of using periodic in situ ozone spiking as an energy-efficient fouling mitigation strategy. Bench-scale experiments using an alumina tubular ceramic membrane and real surface water revealed that the permeability could be restored to 96% of its initial value within 45 min of ozone exposure. Considering system hydraulics and ozone decomposition, the concentration of ozone inside the membrane pores was estimated to be between 1.6 and 0.9 mg L-1, depending on the position along the tubular membrane. Ozone spiking appears to be more energy-efficient compared to continuous ozonation, potentially allowing for 40 to 55% less energy required. The work further proposes a simple approach to optimize ozone spiking frequency, which seeks to balance the trade-offs between additional pumping energy due to fouling buildup and the energy required for ozonation. If validated on each particular case, considering the specific fouling potential and local energy requirements, the approach presented here can be an important asset toward the optimal design of energy-efficient ozone-ceramic treatment facilities.