Nobuyuki Hayashi

Hikami-taka sanitary association technical section
(45, Minaminaka, Sannancho, Hikami-gun, Hyogo 669-31 Japan)

Abstract

We made an inverstigation regarding the influence of NO2-N and error of analsis for COD (Mn), which is a standard for judging water quality. The error was confirmed, and the system error grows on the value of COD (Mn), because the oxidize reaction by KMnO4 is proportional to the remaining KMnO4. To establish a revision, coefficient came into effect for the traceability of COD (Mn) and the reliance of value at COD (Mn) analysis.

Key words: COD (Mn), NO2-N, system error, revision coefficient