Mechanism of Condensable Particulate Matter transformation and reduction in flue gas scrubbing process

• Published in: Fuel (Guildford) 2024-06, Vol.366, p.131255, Article 131255
• Main Authors: Zhang, Zhuping, Wang, Lu, Li, Yuzhong, Zhang, Hongwei, Gan, Zongwei, Deng, Lejun, Chen, Tailin
• Format: Article
• Language: English
• Subjects: Condensable Particulate Matter; Flue gas scrubbing; Reduction; Wet flue gas desulfurization
• ISSN: 0016-2361
• DOI: 10.1016/j.fuel.2024.131255

•Condensable Particulate Matter (CPM) can be removed in flue gas scrubbing process.•Part of CPM is removed through converting into particles during flue gas scrubbing.•Dissolution and condensation of CPM precursors contribute to its removal.•Some components in spray droplets can become CPM through evaporation.•A demister installed at the outlet of a scrubber contribute to the removal of CPM. Condensable particulate matter (CPM) is a kind of pollutant that is gaseous in stack and granular after being discharged into atmosphere. Existing studies have shown that CPM can be removed by wet flue gas desulfurization (WFGD) synergistically, but the mechanism is unclear. In this paper, a simulated WFGD experimental system was established, and the transformation and removal mechanism of CPM in the process of flue gas spray cooling was explored by adjusting experimental parameters. The research shows that the process can realize removal of CPM, which is reflected in two aspects: part of CPM is converted into filterable particulate matter (FPM), and part of CPM is absorbed and deposited by spraying liquid. The mechanism involved is condensation and dissolution, and dissolution plays a major role. There may be two ways to convert CPM into FPM in scrubber: one is FPM formed by homogeneous or heterogeneous condensation of CPM gaseous precursors; the other is that after the spray droplets absorb CPM, FPM formed by those very small droplets of spraying liquid. The demister at the outlet of the scrubber can reduce the discharge concentration of CPM and FPM.