Abstract：In order to solve the problem that SO2 fluorescence signals was faint and always cannot be distinguished with noises, a novel method based on wavelet optimization ensemble empirical mode decomposition (EEMD) was proposed. The SO2 detection system had been built. Using the SO2 detection system, SO2 concentration can be detected. The average error of detection was 0.0011, and the correlation coefficients between SO2 concentration and the fluorescence intensity was 0.9787. Wavelet optimization EEMD denoising method were applied to SO2 detection system, the results showed that the signal noise ratio(SNR) was 224.7958, the mean squared error(MSE) was 1.01×10-7, and the normalized correlation coefficient(NCC) was 0.9973. The correlation coefficients between SO2 concentration and fluorescence intensity was 0.9936. Compared with the wavelet denoising method and EEMD denoising method, the wavelet optimization EEMD method has the best denoising effect. The proposed method is superior to wavelet denoising method and EEMD denoising method.
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2020, Vol. 41 
