A flow arrangement for an electrolyser, an electrolyser, electrolysis installation, operating method and method of manufacture

A method of operating an electrolyser, the electrolyser comprising:

• first and second porous walls corresponding to first and second electrodes of the electrolyser;
• an inlet chamber disposed between the first and second porous walls and configured to receive a fluid through an inlet;
• first and second outlet chambers for retaining respective fluid reaction products of electrolysis, separated from the inlet chamber by the first and second porous walls respectively;
• wherein one of, or each of, the first and second porous walls has a discontinuous porous structure, wherein the or each porous wall having the discontinuous porous structure:
• comprises a body having an inlet side adjacent to the inlet chamber and an outlet side adjacent to the respective outlet chamber, wherein the body is elongate along a longitudinal direction, and has a thickness direction from the inlet side to the outlet side;
• comprises a plurality of porous regions extending through the body at discrete locations to permit the fluid to flow from the inlet chamber to the respective outlet chamber,
• wherein each porous region defines a respective network of flow paths through the body;
• the method, comprising:
• providing an inlet flow of electrolyte fluid to the inlet chamber via the inlet to conduct electrolysis half-reactions at the first and second electrodes provided by the first and second porous walls, to generate respective fluid reaction products;
• wherein the electrolyte fluid and/or associated ions flow into the porous regions of the or each electrode having the discontinuous porous structure to react with the respective electrode;
• wherein each of the first and second outlet chambers retains the respective fluid reaction product for discharge, and the respective electrode inhibits return flow of the fluid reaction product from the outlet chamber to the inlet chamber.

A method of manufacturing a porous wall having a discontinuous porous structure, for an electrolyser, comprising:

• providing a body for the porous wall, wherein the body is elongate along a longitudinal direction, and has a thickness direction from a first side to a second side;
• removing material from the body to form a plurality of open regions, the open regions extending through the body at discrete locations, wherein each open region is elongate along a path through the body having a longitudinal component;
• applying an electrocatalyst composition to the body so that it flows into the open regions;
• heating the body to perform a heat treatment operation in which an electrocatalyst component of the electrocatalyst composition forms a porous region at each location of the open regions, wherein each porous region defines a respective network of flow paths through the body to permit fluid to flow from the first side of the body to the second side of the body.