Validation of a Multidimensional Smouldering Model
Smouldering is a flameless form of combustion driven by exothermic
oxidation surface reactions within a porous medium. Smouldering is being
harnessed by engineers to remediate liquid hydrocarbon and Per- and
polyfluoroalkyl substances (PFAS) contaminated soils, drive
waste-to-energy processes, and to provide off-grid sanitation solutions
in the developing world. In all applications, initial heat is supplied
to a small ignition region and air is injected to support
self-sustaining smouldering. However, engineers and researchers have
only a few tools to utilize and study smouldering, and this is a key
limitation. This work addresses this limitation via developing a novel
multidimensional, thermodynamic-based smouldering model. This model is
valuable for both engineers and researchers to gain a deeper
understanding into key physical (e.g., temperature, air flow, and oxygen
distribution), chemical (e.g., a non-uniform oxidation reaction), and
operational processes in smouldering systems (e.g., the effects of
radial heat losses on energy efficiency). As smouldering gains
popularity as a novel technology, there is a growing need for robust
smouldering models.
This presentation highlights both the model development and validation
from highly instrumented experiments. These results highlight the
processes that govern key operational characteristics, such as peak
temperature and air flow distributions (critical for PFAS remediation)
and overall energy efficiency (critical for waste-to-energy and
sanitation purposes). Altogether, this work is anticipated to support
investigating, designing, and optimizing the future smouldering systems
for a range of applications such as PFAS remediation, waste-to-energy,
and improving sanitation in the developing world.