Characterizing and locating air pollution sources in a complex industrial district using optical remote sensing...

Area of Science:

• Environmental Science
• Analytical Chemistry
• Atmospheric Chemistry

Background:

• Volatile organic compounds (VOCs) are significant urban air pollutants, often originating from nearby industrial zones.
• Identifying specific VOC emission sources in complex industrial districts is challenging.

Purpose of the Study:

• To develop and validate a dynamic approach for locating VOC emission sources in industrial areas.
• To combine multi-path open-path Fourier transform infrared spectrometry (OP-FTIR) with principal component analysis (PCA) for source identification.

Main Methods:

• Deployed multiple open-path OP-FTIR monitoring lines over three months in an industrial district.
• Utilized principal component analysis (PCA) for statistical modeling and dimensionality reduction of collected data.
• Employed close-cell FTIR to verify identified emission sources from factory exhaust stacks.

Main Results:

• Identified N,N-Dimethyl formamide (DMF), 2-butanone, toluene, and ethyl acetate as major VOCs, with DMF exceeding ambient standards.
• PCA analysis pinpointed three primary emission sources: PU coating, chemical packaging, and lithographic printing industries.
• Demonstrated the feasibility of using multi-path OP-FTIR combined with wind data and PCA for source localization.

Conclusions:

• The integrated approach of instrumental measurement (OP-FTIR) and statistical modeling (PCA) provides a systematic method for identifying industrial VOC emission sources.
• Wind data incorporation with PCA enhances the accuracy of pinpointing emission locations in complex environments.
• This study validates the effectiveness of multi-path OP-FTIR for real-world application in industrial air quality monitoring.