Abstract
Considerable amount of experiments regarding smoldering combustion of peat had been conducted through various methods of experiment, modeling, and field study, with factors affecting the smoldering combustion of peatlands include: moisture content, density, porosity, wind speed, etc. However, it can be seen that some researches that focus on the influence of moisture content did not consider the evaporation and drying stages of the smoldering front; thus, the parameters of the test results were determined based on initial moisture content prior to combustion. This experiment was conducted in order to study the smoldering combustion of the peat layer which resembles the real conditions in the field, which involves the stages of preheating, evaporation, drying, pyrolysis, and char oxidation. Varying values of moisture content, increasing with depth, were prepared by drying the raw peat sample (sampling results) at 105 °C for 4, 8, 12, 16, 20, and 24 h. The resulting samples were then placed inside a reactor measuring 10 cm × 10 cm with depth of 20 cm, with each layer of peat with different moisture content at 2.5 cm thick; thus, obtaining a layered peat configuration with the dry peat layer on the surface (MC ~8.5%) and the wet peat layer (raw peat) at the bottom of the reactor. Measurements of smoldering spread, evaporation rate, and mass loss (including evaporation rate) were gathered through instruments of thermocouple, soil moisture sensor, and weight balance, respectively, in real time. The results from the experiment suggested that the evaporation rate, smoldering propagation, and depth of burn depended on the thickness of the burnable dry peat layer, or equivalent to the available amount of heat, which will be partially transferred (converted) for heating, evaporation, pyrolysis, and combustion processes. Therefore, smoldering cannot propagate on the moist peat layer because it will always start with evaporation and drying process. The smoldering front will always be bordered by dry peat layer up to the point where the heat generated is equal or less than the amount needed for evaporation, which is the critical point of extinction.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Abbreviations
- MC:
-
Moisture content (% weight)
- IC:
-
Inorganic content (%)
- HHV:
-
Higher heat value (MJ/kg)
- LHV:
-
Lower heat value (MJ/kg)
- H:
-
Hydrogen content (%)
- Q :
-
Heat (of generation or evaporation) (kW)
- ṁ :
-
Mass consumption rate of peat (kg/h)
- ṁ :
-
Evaporation rate (kg/h)
- cp:
-
Heat capacity of water vapor (kJ/kg·K)
- p :
-
Peat
- v :
-
Water vapor
- g :
-
Generation or release (of heat)
- ev:
-
Evaporation
References
Page, S. E., et al. (2002). The amount of carbon released from peat and forest fires in Indonesia during 1997. Nature, 420(6911), 61–65.
Turetsky, M. R., et al. (2015). Global vulnerability of peatlands to fire and carbon loss. Nature Geosci, 8(1), 11–14.
Rein, G. (2013). Smouldering fires and natural fuels, in fire phenomena and the earth system (pp. 15–33). Wiley.
Perdana, L., et al. (2018). Hydrophilic and hydrophobic characteristics of dry peat. In IOP Conference Series: Earth and Environmental Science. IOP Publishing.
Benscoter, B., et al. (2011). Interactive effects of vegetation, soil moisture and bulk density on depth of burning of thick organic soils. International Journal of Wildland Fire, 20(3), 418–429.
Watts, A. C. (2013). Organic soil combustion in cypress swamps: Moisture effects and landscape implications for carbon release. Forest Ecology and Management, 294, 178–187.
Frandsen, W. H. (1987). The influence of moisture and mineral soil on the combustion limits of smoldering forest duff. Canadian Journal of Forest Research, 17(12), 1540–1544.
Huang, X., Rein, G., & Chen, H. (2015). Computational smoldering combustion: Predicting the roles of moisture and inert contents in peat wildfires. Proceedings of the Combustion Institute, 35(3), 2673–2681.
Huang, X., & Rein, G. (2015). Computational study of critical moisture and depth of burn in peat fires. International Journal of Wildland Fire, 24(6), 798–808.
McMahon, C. K., Wade, D. D., & Tsoukalas, S. N. (1980, June 22–27). Combustion characteristics and emissions from burning organic soils. In 73rd Annual Meeting of the Air Pollution Control Association. Montreal, Quebec, June 22–27, pp. 2–16.
Wein, R.W., & Maclean, D. (1983). Fire behaviour and ecological effects in organic terrain.
Rein, G., et al. (2008). The severity of smouldering peat fires and damage to the forest soil. CATENA, 74(3), 304–309.
Artsybashev, E. (1983). Forest fires and their control.
Rein, G. (2009). Smouldering combustion phenomena in science and technology.
Prat-Guitart, N., et al. (2016). Effects of spatial heterogeneity in moisture content on the horizontal spread of peat fires. Science of the Total Environment.
Frandsen, W. H. (1997). Ignition probability of organic soils. Canadian Journal of Forest Research, 27(9), 1471–1477.
Garlough, E. C., & Keyes, C. R. (2011). Influences of moisture content, mineral content and bulk density on smouldering combustion of ponderosa pine duff mounds. International Journal of Wildland Fire, 20(4), 589–596.
Usup, A., et al. (2004). Combustion and thermal characteristics of peat fire in tropical peatland in Central Kalimantan. Indonesia. Tropics, 14(1), 1–19.
Dianti, A., et al. (2018). Effect of rewetting on smouldering combustion of a tropical peat. E3S Web Conference, 67.
Nadhira Gilang, R., et al. (2018). Laboratory scale experimental study of foam suppression on smouldering combustion of a tropical peat. Journal of Physics: Conference Series, 1107(5), 052003.
Huang, X., et al. (2016). Experimental study of the formation and collapse of an overhang in the lateral spread of smouldering peat fires. Combustion and Flame, 168, 393–402.
Huang, X., & Rein, G. (2017) Downward spread of smouldering peat fire: The role of moisture, density and oxygen supply. International Journal of Wildland Fire.
Palamba, P., et al. (2018). Drying Kinetics of Indonesian Peat. International Journal of Technology, 9(5), 1006–1014.
Ballhorn, U., et al. (2009). Derivation of burn scar depths and estimation of carbon emissions with LIDAR in Indonesian peatlands. Proceedings of the National Academy of Sciences, 106(50), 21213–21218.
Acknowledgements
The authors would like to thank the financial support provided by Ministry of Research, Technology and Higher Education of the Republic of Indonesia through Penelitian Disertasi Doktor (PDD) 2018 funding scheme under Grant No. 07/UN20.2.2/PL/PDD/2018 managed by the Institute for Research and Public Services (LPPM) of Cenderawasih University.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2020 Springer Nature Singapore Pte Ltd.
About this paper
Cite this paper
Palamba, P. et al. (2020). Experimental Investigation of Smoldering Combustion of Tropical Peat Layer Under Stratified Moisture Content. In: Wu, GY., Tsai, KC., Chow, W.K. (eds) The Proceedings of 11th Asia-Oceania Symposium on Fire Science and Technology. AOSFST 2018. Springer, Singapore. https://doi.org/10.1007/978-981-32-9139-3_44
Download citation
DOI: https://doi.org/10.1007/978-981-32-9139-3_44
Publisher Name: Springer, Singapore
Print ISBN: 978-981-32-9138-6
Online ISBN: 978-981-32-9139-3
eBook Packages: EngineeringEngineering (R0)