CONTINUOUS MEASUREMENT METHOD FOR HYDROGEN GAS CONCENTRATION AND HYDROGEN GAS CONCENTRATION MEASUREMENT DEVICE USED IN SAME

Provided are a continuous measurement method for hydrogen gas concentration enabling direct measurement of the dissolved hydrogen gas concentration in a liquid to be measured without using a pH sensor and a hydrogen gas concentration measurement device used in the method. A pipe 2 is placed in such a manner as to come in contact with a hydrogen water, and from the hydrogen water, hydrogen gas passed through the pipe 2 is introduced into a hollow part 3. A first gas is introduced into the hollow part 3 by a gas supply pump 14a, and a second gas is extracted and exhausted from the hollow part 3 by a gas exhaust pump 15a. The hydrogen gas that has passed through the pipe 2 and has been introduced into the hollow part 3 from the hydrogen water is circulated by a circulation pump 16a through a gas supply conduit 14 into the hollow part 3. When the equilibrium state between the concentration of hydrogen gas contained in the hydrogen water and the hydrogen gas concentration in the hollow part 3 is achieved, the hydrogen gas concentration in the hollow part 3 is measured. The relation between the concentration of hydrogen gas contained in a hydrogen water and the hydrogen gas concentration in the hollow part 3 is previously determined, and on the basis of the relation, the concentration of hydrogen gas contained in the hydrogen water is calculated from the measured hydrogen gas concentration.