Mitigating smoldering peatland fire via buried heat pipes : a new concept of underground firebreak

Abstract

Background: Smoldering underground fires in peatlands are among the most persistent and destructive wildfire types, but resisting conventional suppression methods. Aims: This study experimentally evaluates a heat-pipe-based underground firebreak concept as a passive cooling strategy to mitigate smoldering propagation in stratified peat profiles. Methods: Laboratory-scale experiments were conducted with an upper dry peat layer overlying a saturated layer. Heat pipes of varying lengths, geometries and quantities were installed with the condenser section positioned at the dry–saturated interface. Key results: Under these conditions, heat pipes reduced peak smoldering temperatures and, in some configurations, quenched combustion. The intervention expanded the high-moisture, non-combustible region (‘safe zone’) more than fivefold compared with control tests. Longer pipes and configurations with larger condenser surface areas demonstrated greater thermal suppression effects. Conclusion: The results provides a laboratory-scale proof of concept that heat pipes can function as passive thermal sinks and promote moisture redistribution at the dry–saturated interface in peat columns. Implications: These findings are limited to controlled laboratory experiments. Substantial additional experimental, modeling and field research are required before assessing real-world deployment potential.