Gas Density Meter Applications: Faster Hydrogen Concentration Monitoring

General H₂O electrolysis process

Measuring hydrogen concentration in a typical H₂O electrolysis process has the following challenges:

(1) Conventional thermal conductivity meters and alloy thin film meters; Slow response, tens of seconds to 60 seconds
(2) The anode side need to multiple pretreatments for water separation and dehumidification.

In H₂O electrolysis plants that produce hydrogen, cross-leakage to the anode and cathode sides due to membrane degradation is an issue for safety management, and the inability to achieve a fast response in general hydrogen concentration measurement is a major issue for safety monitoring.

Since the gas components of the H₂O electrolysis process are hydrogen and oxygen, it is possible to estimate the gas concentration by gas density. The applicability of gas density meters in hydrogen concentration measurement is introduced in this document.

Two pairs of piezoelectric elements for drive and detection are attached on four points of a thin-wall cylindrical resonator. A platinum temperature sensor is mounted to the density sensor.

The sample gas from inlet passes over the outside of the thin-walled cylindrical resonator and is exhausted at the gas outlet.

Fig. 4 Detector structure