| 摘要 |
PROBLEM TO BE SOLVED: To stably measure by fluorography the concentration of a specific chemical substance or specific drainage contained in raw water containing at least Crwhile reducing Crto Crwith a reductant.SOLUTION: A concentration measuring method of the present invention includes: a reduction step of reducing Crby adding a reductant to a liquid sample obtained from raw water containing at least Cr; a removal step of adjusting the pH of the liquid sample having the reductant added thereto to precipitate Cr ions and Fe ions present in the liquid sample as a hydroxide, and removing the precipitated hydroxide; a measuring step of measuring the fluorescence of the liquid sample having the hydroxide removed therefrom with use of a preliminarily prepared database related to fluorescence characteristics of a specific chemical substance or specific drainage; and a concentration calculation step of, with use of a preliminarily prepared interrelation between the fluorescence intensity and the concentration of the specific chemical substance or specific drainage, calculating the concentration of the specific chemical substance or specific drainage on the basis of the measurement result of the fluorescence of the liquid sample. |
