ONLINE METHOD FOR DETECTING CONCENTRATION OF GAS PHASE ALKALI METAL IN BOILER COMBUSTION FLAME

摘要

An online method for detecting the concentration of the gas phase alkali metal in boiler flame by directly using flame emission spectroscopy analysis. First selecting the characteristic spectral lines of the alkali metal to be detected; constructing a fitted model for the characteristic spectral line emission strength with respect to the flame temperature and the gas phase alkali metal concentration; calibrating and determining the fit coefficient by means of experiments; measuring the emission optical spectrum of the flame target using a portable optical fiber optical spectrometer so as to obtain the flame temperature and the characteristic spectral line emission strength of the alkali metal; substituting same into the constructed fitted model having the known fit coefficient to calculate the concentration of the gas phase alkali metal in the flame. The method enables easy and accurate online measurement of the concentration of the gas phase alkali metal in the combustion flame in the boiler, and simultaneously detects the concentration of multiple alkali metals. The device is simple, has a low cost, and is suitable for industrial on-site measurement.