Abstract
Biocarbon is a promising alternative to replace fossil carbon as reductant for metal production with benefits to reduce greenhouse gas emissions and increase the sustainability of the metallurgical industry. As a carbon and energy intensive industry, a significant amount of biocarbon needs to be produced, handled, transported and stored for further utilization in metal production processes. Biocarbon is a reactive porous material and can undergo self-heating that is related to spontaneous exothermic reactions at low temperatures. The biocarbons can be produced from different biomass materials and under different conditions, and have various physical and chemical properties. The biocarbons with different properties have different tendency in terms of self-ignition and risk of fire. In addition, storage and transportation conditions play also important roles in causing the self-ignition of biocarbon, including gas atmosphere, temperature, heat and mass transfer to surroundings, humidity, etc. Several studies have been conducted to investigate reasons for causing biocarbon self-ignition, including conversion behaviour and mechanisms of biocarbon self-ignition and potential mitigation measures. The main objective of this review is to survey studies on the self-ignition of biocarbons by correlating them to biocarbon production and storage conditions and provide background information for safe transportation and storage of biocarbon.