Pressure electrolyzer and method for switching off a pressure electrolyzer

A pressure electrolyser, comprising:

• a pressure reservoir;
• an electrolytic cell block containing a number of electrolytic cells and positioned in the pressure reservoir, the electrolytic cells each containing anodes and cathodes;
• and an electrolyte circulatory system for supplying electrolyte to the anodes and cathodes, the circulatory system including an oxygen separator operative to separate gaseous oxygen formed during operation of the pressure electrolyser and a hydrogen separator operative to separate gaseous hydrogen formed during operation of the pressure electrolyser, and a store of an inert gas to inert the pressure electrolyser when it is switched off, the store of inert gas being supplyable to the oxygen separator, the electrolyte circulatory system further including a connecting line arranged so that a part of the electrolyte can be pushed out of the hydrogen separator when the inert gas is applied to the oxygen separator so as to displace the gaseous hydrogen.

A process for switching off a pressure electrolyser which comprises a pressure reservoir and an electrolytic cell block containing a number of electrolytic cells and positioned in the pressure reservoir, the electrolytic cells each containing anodes and cathodes and an electrolyte circulatory system for supplying electrolyte to the anodes and cathodes, an oxygen separator to separate gaseous oxygen formed during operation of the pressure electrolyser and a hydrogen separator to separate gaseous hydrogen formed during operation of the pressure electrolyser being provided, an inert gas, the process comprising the steps of:

• switching off the pressure electrolyser;
• and feeding inert gas to the oxygen separator so that a part of the electrolyte is pushed out of the hydrogen separator via a connecting line contained in the electrolyte circulatory system, thereby displacing the gaseous hydrogen.