Direct Observation of Sulfate Explosive Growth in Wet Plumes Emitted From Typical Coal-Fired Stationary Sources

Xiang Ding, Qing Li, Di Wu, Xiaoyan Wang, Mei Li, Tao Wang, Lin Wang, Jianmin Chen

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)


The origins of atmospheric sulfate production have previously been explained by focusing on air quality models and complex chemical reaction processes. Here, we first report direct observations of sulfate production in stack plumes discharged from coal-fired power plants, industrial boilers, and sintering plants equipped with wet desulfurization systems. Less than one third of the particulate SO42− in plumes is attributed to dust-SO42− and SO3 measured in stacks. The SO2 aqueous-phase oxidation process is critical in explaining the unknown sulfate formation in plume droplets with pH values ranging from 2.3 to 2.8. When the rapidly formed sulfate in wet plumes is included, a notable amount of underestimated sulfate (∼0.24 Tg in 2017) is emitted from industrial stacks in China and can partially explain the “missing sulfate” on driving most particle pollution episodes. Policy-making targeting particulate emissions is suggested to substantially reduce sulfate emissions for further air quality improvement.

Original languageEnglish
Article numbere2020GL092071
JournalGeophysical Research Letters
Issue number6
Publication statusPublished - 28 Mar 2021


  • acidic fog
  • air pollution
  • climate change
  • coal-fired power plants
  • SO oxidation
  • sulfate emission

ASJC Scopus subject areas

  • Geophysics
  • Earth and Planetary Sciences(all)

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