Advancing Efficiency in EDBM: Investigating the Interplay of Pressure Variations and Volume Management

Abstract

Addressing the challenge of industrial sustainability in the context of climate change requires the adoption of technologies that reduce energy consumption and critical raw material reliance. Electrodialysis with Bipolar Membranes (EDBM) is an electro-membrane technology offering a promising alternative to conventional methods for the production of essential chemicals such as HCl and NaOH. Traditionally, these chemicals are produced via energy-intensive processes that require a subsequent water dilution, leading to a significant energy loss. EDBM technology directly produces acidic and alkaline solutions at the desired concentrations, thus avoiding the need for energy-consuming dilution steps. This technology has been found promising in the field of wastewater treatment, specifically within Minimal Liquid Discharge (MLD) or Zero Liquid Discharge (ZLD) treatment chains. With this respect, EDBM guarantees substantial energy savings and economic benefits by facilitating in-situ chemical production. Despite EDBM potential, its scalability and efficiency under various conditions are still poorly studied due to the predominance of laboratory-scale studies, with flow rates and pressure impacts mostly underexplored. This work presents a comprehensive investigation of the impact of applying differential pressures across the EDBM compartments on its performance, marking a significant step forward for the full industrial applicability of this technology. Experiments were carried out on the largest EDBM unit investigated to date: our findings demonstrate that an appropriate manipulation of pressures between EDBM channels can significantly enhance process efficiency and reduce specific energy consumption. This research enhances EDBM technology understanding, affirming its sustainability and benefits for economic efficiency and environmental conservation.