Document


Title

Can peat soil support a flaming wildfire?
Document Type: Journal Article
Author(s): Shaorun Lin ; Peiyi Sun ; Xinyan Huang
Publication Year: 2019

Cataloging Information

Keyword(s):
  • critical heat flux
  • fire spread
  • ignition energy
  • moisture
  • peatland
  • piloted ignition
  • smoldering
Topic(s):
Record Maintained By:
Record Last Modified: August 22, 2019
FRAMES Record Number: 58470

Description

Smouldering wildfire in peatlands is one of the largest and longest-lasting fire phenomena on Earth, but whether peat can support a flaming fire like other surface fuels is still unclear. Our experiments demonstrate the successful piloted flaming ignition of peat soil with moisture up to 100 wt-% under external radiation, indicating that flames may rapidly spread on peatland before transitioning to a conventional smouldering peat fire. Compared with smouldering ignition, flaming ignition of peat is more difficult, requiring a higher minimum heat flux and tripling the ignition energy. The propensity for flaming increases with a drier peat and greater external heating. We also found that the flaming ignition temperature increases from 290 to 690°C as the peat moisture increases to 100 wt-%. Flames from peat soil are much weaker than those of pine needles and wood, and they eventually transition to smouldering. The heat of flaming is estimated to be 13 MJ kg−1, close to the heat of smouldering. The measured CO/CO2 ratio of flaming peat fires is less than 0.02, much smaller than 0.2 for smouldering peat fires. This research helps understand the development of peat fire and the interaction between flaming and smouldering wildland fires.

Online Link(s):
Citation:
Lin, Shaorun; Sun, Peiyi; Huang, Xinyan. 2019. Can peat soil support a flaming wildfire? International Journal of Wildland Fire 28(8):601-613.