Influence of operating parameters and membrane properties on the performance of electrochemical membrane system for solution pH adjustment

• Main Author: Ong, Erika Ling Qi
• Other Authors: She Qianhong
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Engineering; Electrochemical membrane system
• Online Access: https://hdl.handle.net/10356/177384
• Institution: Nanyang Technological University

The increasing demand for water underscores the importance of water treatment, wherein pH adjustment is essential in the field of water treatment applications. Currently, methods for pH adjustment predominantly involve chemical dosing and electrochemical techniques, although effective but fraught with environmental concerns and high costs. One promising alternative that mitigate these limitations is the integration of a pressure-driven membrane with an electrochemical cell, allowing pH adjustment without use of chemicals. Through a qualitative investigation leveraging theoretical models and experimental findings, the relationship among factors such as pH change, surface loading rate, current density, electrolyte concentration, energy consumption, and membrane properties will be explored. The study aims to better understand how electrochemical membrane system (EMS) works and the impacting factors to help improve control over system pH. It was demonstrated that pH change is more obvious with lower surface loading rate and specific energy consumption increased with higher membrane electrical resistance, higher current density, lower electrolyte concentration and lower surface loading rates. Slight pH change (i.e., to acidic pH 4.5 and alkaline pH 10) only require extremely low SEC of 0.01 kWh/m3 highlighting the potential of application of EMS.