To supply pure water without using a pump by making the level of the pure water flowing in a gas non-return device lower than the level of a water electrolyzer in contact with an anode.
A gas non-return device 24 is fixed to a pipe 27 for supplying pure water to a water electrolyzer 25. Oxygen and the pure water stored in a pure water tank 23 are supplied to the anode of the electrolyzer 25 by the pipe 27. Further, a level difference H is formed between the level of pure water flowing through the gas non-return device 24 and that of the pure water in contact with the anode. The oxygen generated from the anode is introduced into the tank 23 by buoyancy. In this case, when the level difference H is ≥150mm, any oxygen is not accumulated in the non-return device 24, the passage of pure water is not blocked by the gas-phase oxygen, and the pure water is sent to the electrolyzer 25 without using a pump.
KURATA YOSHIAKI
TAKAHASHI TAKEO
