Noboru Tanikawa*, Toshio Takemoto*, Toshitada Imai* and Kohei Urano**

*Tokyo Metropolitan Research Institute for Public Cleansing
**Laboratory of Safety and Environmental Engineering, Faculty of Engineering, Yokohama National University

+ Correspondence should be addressed to Noboru Tanikawa:
Tokyo Metropolitan Research Institute for Public Cleansing
(3 Yumenoshima, Koto-ku, Tokyo 136 Japan)

Abstract

Various continuous NH3 analyzers; catalytic conversion type, ion electrode type and UV type were compared in analysis accuracy with the indophenol method. The catalytic conversion type NH3 analyzer denoted slightly lower values than those by the indophenol method. The reason for the difference was estimated that the concentrations of NO, CO2 and NH3 in flue gas varied in shorter time than the measuring intervals of 1 s. The ion electrode type NH3 analyzer also denoted slightly lower values, because the flow rate of gas and absorption solution were slightly varied and the volume of the absorption solution changed with H2O condensation from the flue gas. The UV type NH3 analyzer also denoted slightly lower values due to the influence of coexistent gases such as NO and SO2 .

Key words: NH3 analyzer, indophenol method, municipal incinerator, flue gas, NOx removal