NTPC NETRA, in collaboration with CSMCRI Bhavnagar, has setup a 24 TPD Electrodialysis Reversal (EDR) based water treatment plant at the NETRA campus to demonstrate an energy-efficient and sustainable technology for producing high-quality process water with minimal chemical usage and low operational cost. 
Electrodialysis (ED) is an electro-membrane process that uses alternating Anion–exchange membrane (AEM) and Cation-exchange membrane (CEM), placed between electrodes. 
In electrodialysis, suspended solids which carry positive or negative electrical charges can increase the resistance of the membrane dramatically, are deposited on the membrane surface. This problem has been eliminated to a large extent by reversing in certain time intervals the polarity of the applied electrical potential which results in a removal of charged particles that have been precipitated on the membranes. This technique is referred to as electrodialysis reversal (EDR).