Anionic membranes of low permselectivity in pilot plant operation

The behaviour of low permselectivity anionic membranes in pilot plant operation was studied by substituting such membranes for the conventional anionic ones used in electrodialysis. The product flow rate or electrical current is limited in electrodialysis because of scaling and fouling problems associated with the anionic membrane. Higher electrical currents and flow rates were achieved with the new anionic membranes (Neginst-P.E.N. developed in our laboratories) without the associated effects of fouling and scaling. While these anionic membranes require more electrical power per unit of desalinized water than electrodialysis, the additional electrical costs are more than offset by operation at higher current densities.