This invention relates to an electric double layer capacitor electrochemical cylinder (11) made up of concentric layers of capacitors (16), current collectors (14a, 14b, 14c), ion specific membranes (18, 18a, 18b) and dielectric spacer (20) wrapped around an inner support tube (12) that can be used as a high capacitance capacitor and to remove dissolved solids from a liquid stream such as water, acid, aqueous or non-aqueous.