Experimental study of the ignition conditions for self-sustained smouldering in peat

The initiation of smouldering peat fire by a glowing firebrand

“…Although the hydrophilicity or hydrophobicity of peat soils may change during the heating process, the extent of their change is a function of initial soil properties and heating conditions (Wu et al 2020). In this work, heating was performed at lower temperatures than that in Debano (2000) cited as being problematic, and the method we used to achieve peat soils with different moisture contents has been widely used and validated in the literature (Prat et al 2015;Huang et al 2016a;Huang and Rein 2017;Hu et al 2019;Lin et al 2019;Christensen et al 2020;Lin et al 2021aLin et al , 2021bCui et al 2022).…”

“…Smouldering peatland fires were brought to the forefront of scientific debate following the 1997 extreme haze event in south-east Asia from burning peatlands during a particularly strong El Nino season (Page et al 2002). Following this event, many research studies have targeted understanding the characteristics of smouldering peat fires, including combustion chemistry (Huang and Rein 2016), ignition (Lin et al 2019;Cui et al 2022;Santoso et al 2022), fire spread (Prat et al 2015;Yang and Chen 2018;Huang and Rein 2019;Qin et al 2022aQin et al , 2022bZhang et al 2024), emissions (Hu et al 2018;Kohlenberg et al 2018;Lin et al 2021b), detection (Atwood et al 2016;Rein et al 2017), and suppression (Ramadhan et al 2017;Santoso et al 2021;Mulyasih et al 2022). A recent review paper provided a comprehensive overview of smouldering wildfires, together with their associated environmental and health issues, as well as the challenges in prevention and mitigation (Rein and Huang 2021).…”

Laboratory benchmark of low-cost portable gas and particle analysers at the source of smouldering wildfires

“…Peat samples deposited in an open-top reactor with internal dimensions of 20 × 20 × 10 cm (built from mineral fibre boards) were ignited using a helical ignition coil (length 18 cm, diameter 1 cm) mounted on one side board (5 cm from the top surface) following the reactor and ignitor design of previous research (Huang et al 2016;Hu et al 2019a). At the ignition stage, the ignition coil had a constant power supply of 100 W, and it was turned off when the sample had 10% mass loss (Cui et al 2022). To monitor smouldering dynamics, a mass balance (Mettler Toledo, resolution 0.01 g) was used to record real time mass loss; 12 thermocouples (K-type) were inserted into the reactor to measure the soil temperature profile (three rows and four columns); A Gopro and a FLIR infrared camera were installed to record the visual and infrared signature of the experiments (shown in Fig.…”

“…Previous work also revealed that fire emissions are correlated with fire dynamics (Hu et al 2019a). Defining different stages of fire evolution using the mass loss progression can facilitate the calculation and comparisons of various experimental results (Cui 2022).…”

Resurfacing of underground peat fire: smouldering transition to flaming wildfire on litter surface

“…Peatlands are essential ecosystems and carbon sinks globally, supporting biological diversity for a wide variety of wildlife habitats (Page et al 2011;Lin et al 2020), and storing nearly one-third (~600 Gt) of the terrestrial organic carbon on the planet (Freeman et al 2001;Page et al 2011). However, peatlands are threatened by wildfires driven by anthropogenic and natural reasons (Turetsky et al 2015;Rein and Huang 2021;Santoso et al 2022;Cui et al 2023). For example, in Malaysia, land clearance activities such as slash and burn practised by the local community are the main contributors to peat fire spread to forest reserves, leading to crossborder haze events and many health issues for nearby residents.…”