Apparatus for removal of ions, and a method for removal of ions

A method to remove ions, the method comprising:

• providing an electrical potential difference between a first electrode and a second electrode, in a housing;
• allowing water to flow between the first and second electrodes from an inlet of the housing to an outlet of the housing;
• and
• adjusting a flow velocity of a first portion of the water with respect to a second portion of the water using a velocity adjuster, wherein the velocity adjuster comprises a porous material and a flow resistance in a central region of the velocity adjuster is larger than closer to an edge of the velocity adjuster, causing the velocity of water passing through the central region of the velocity adjuster to be reduced compared to water passing closer to the edge of the velocity adjuster,
• wherein the flow velocity of the first portion of the water is lower than the flow velocity of the second portion of the water and the first portion of the water is flowing further away from the first electrode or the second electrode than the second portion of the water.

An apparatus to remove ions from water, the apparatus comprising:

• a housing;
• an inlet to let water into the housing;
• an outlet to let water out of the housing;
• a first electrode and a second electrode, connected to a power controller configured to apply an electrical potential difference between the first and the second electrodes;
• and
• a spacer between the first and second electrodes to allow water to flow in between the first and second electrodes and to adjust a flow velocity of a first portion of the water flowing between the first and second electrodes with respect to a second portion of the water flowing between the first and second electrodes, the spacer being a porous material and comprising a helical structure, wherein a flow resistance in a central region of the spacer is larger than closer to an edge of the spacer, causing the velocity of water passing through the central region of the spacer to be reduced compared to water passing closer to the edge of the spacer.