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Porosity-driven biomass combustion

distribution regulates flame propagation and reaction structure, charge dissipation is hindered, leading
time. This work advances the paradigm shift in solid to gradual accumulation and potential electrostatic
waste management from passive disposal toward discharge. Such discharges can generate sparks,
proactive prevention, energy recovery, and carbon igniting nearby combustibles and triggering fires
reduction integration. Future research should extend to or deflagrations, with the risk further exacerbated
other highly porous wastes, such as plastic foam and in low-humidity environments. To mitigate these
textile fragments, aiming to establish a universal urban hazards, preventive measures – including equipment
solid waste combustion and pollution prediction model. grounding, incorporation of conductive materials,
humidity control, and enhanced monitoring of
1.1. Characteristics of deflagration in elongated high-risk zones – are essential for reducing static-
fibrous biomass materials induced fire risks.
Elongated fibrous biomass materials, such as cotton, (iv) Combustion enhancement in high-temperature
pose high safety risks during deflagration, primarily environments: Under high-temperature conditions,
due to their physical structure, chemical properties, and fibrous materials undergo pyrolysis, releasing
environmental conditions. Their characteristics are as volatil2 combustible gases and elevating combustion
follows: risks. Prolonged exposure can lead to heat
(i) High flammability: Elongated fibers, characterized accumulation, potentially triggering spontaneous
by their loose structure and high specific surface combustion even in the absence of an open flame.
area, readily adsorb atmospheric oxygen, ensuring Elevated temperatures further accelerate pyrolysis,
an ample oxidizer supply for combustion. compounding fire hazards. To mitigate these
Their elevated volatile content and low ignition risks, stringent temperature monitoring, optimized
temperature (~250°C) render them highly ventilation management, and strict avoidance of
susceptible to ignition from sparks, static discharge, heat sources are critical. In addition, flame-retardant
or elevated temperatures. These properties facilitate treatments and thermal insulation measures are
rapid combustion propagation, increasing the risk essential to reduce fire and spontaneous combustion
of deflagration, localized pressure surges, and hazards, ensuring fundamental safety in storage and
severe safety hazards. Consequently, stringent fire operation.
prevention and anti-static measures are imperative
across storage, transportation, and operational 1.2. Fundamental principles of deflagration in
phases to mitigate fire and explosion risks. elongated fibrous biomass materials
(ii) Rapid deflagration propagation: Fibrous materials, Biomass deflagration is a complex chemical reaction
when suspended, readily form floc-like clouds process involving the rapid decomposition, oxidation,
that mix with air to generate combustible and combustion of fuel molecules under high-
aerosols. Upon ignition, these mixtures undergo temperature conditions. The main reaction processes
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rapid combustion, releasing substantial heat and and energy release are as follows:
gaseous byproducts, thereby triggering intense (i) Pyrolysis stage: Under high temperatures, biomass
deflagration. This process induces localized high- initially decomposes into gases (such as H , CH ,
4
2
temperature and high-pressure conditions, posing and CO), tar, and solid carbon residues (biochar).
severe risks to equipment integrity and personnel This stage does not require oxygen but generates
safety. The propagation of deflagration may initiate a significant amount of volatile gases, providing
chain reactions, endangering storage facilities, reactants for subsequent oxidation. 34
transportation pipelines, and adjacent infrastructure, (ii) Oxidation stage: In the presence of oxygen, volatile
thereby amplifying potential damage. To mitigate gases undergo rapid oxidation and combustion,
these hazards, stringent control over fiber-air releasing substantial heat. This process is
mixing, reinforced fire prevention and anti-static fundamental to deflagration, as the rapid oxidation
measures, as well as optimized ventilation and of gaseous species results in instantaneous heat
explosion relief designs, are critical. release, generating a high-energy deflagration
(iii) Risk of electrostatic ignition: During processing, effect.
transportation, and storage, fibrous materials (iii) Char combustion stage: Following the combustion
generate static electricity through friction with of volatile gases, the residual biochar undergoes
equipment or pipeline surfaces. Due to their loose gradual oxidation, generating CO and trace amounts
2

Volume 22 Issue 4 (2025) 207 doi: 10.36922/AJWEP025240193