Concentration evaluation method using broadband absorption spectroscopy for sulfur dioxide monitoring

We report on an approach for sulfur dioxide monitoring using broadband absorption spectroscopy in the ultraviolet spectral range. The method was applied in real-time measurements and has the advantage of straightforward data evaluation, limited susceptibility for interference from other gases, and low degree of complexity compared with other real-time optical detection techniques having the same precision. Concentration measurement is demonstrated at atmospheric pressure, which is of interest for pollution emission monitoring, yielding a detection limit of about 1 ppm with 3 s integration time. Comparison is made with low pressure measurements for validation of the accuracy of the method.