Plant and method for producing hydrogen at cryogenic temperature

Abstract

Plant and method for producing hydrogen at cryogenic temperature, comprising: an electrolyzer; a hydrogen circuit to be cooled, comprising an upstream end connected to the hydrogen outlet and a downstream end to be connected to a member for collecting cooled and/or liquefied hydrogen, the plant also comprising a set of heat exchanger(s) in heat exchange with the hydrogen circuit to be cooled, the plant comprising at least one cooling device in heat exchange with at least a portion of the set of heat exchanger(s), the plant further comprising an oxygen circuit comprising an upstream end connected to the oxygen outlet and a downstream end, the oxygen circuit comprising a system for expanding the oxygen stream and at least one heat exchange between the expanded oxygen stream and the hydrogen circuit to be cooled, characterized in that the oxygen circuit comprises at least one oxygen compressor arranged upstream of the oxygen stream expansion system, the oxygen stream expansion system comprising an expansion turbine and in that said expansion turbine and said compressor are coupled to the same rotating shaft to transfer expansion work from the pressurized oxygen stream to the compressor in order to compress the oxygen stream upstream of the turbine.

Dependencies are inferred from the claim text.