Development of high response NOx analyzer for coal-fired power plants

In thermal power plants, the nitrogen oxides produced by the boilers are re moved by de-NOx devices. For efficient operation of the de-NOx device and s table control of the power plant, the speeding up of the response of the NO x analyzer in the flue gas is effective. In past research, we developed hig h response NOx analyzer for LNG-fired power plants by using a technique of increasing sampling gas flow. However, for a coal-fired power plant, it was difficult to develop the high response NOx analyzer using the same techniq ue as previous development, because the coal-fired flue gas contains much d ust. In this research, we developed a high response NOx analyzer for coal-f ired power plant with one-ninth the response time by development of a dust removal sq;stem, and this analyzer can maintain the high dust removal effic iency under the high volume sampling. Then, we applied this high response N Ox analyzer to an actual coal-fired power plant, and we checked the perform ance of it.