What is the primary reason for compacting biomass fuel in storage?

The primary reason for compacting biomass fuel in storage is to reduce the amount of oxygen present within the fuel pile. Biomass fuels, such as wood chips or agricultural residues, are organic materials that are susceptible to spontaneous combustion, a process where the fuel heats up internally due to oxidation and microbial activity until it ignites without an external spark. Compacting the fuel removes air pockets, thereby limiting the oxygen available for these reactions. This reduces the rate of oxidation and the buildup of heat. Lower oxygen levels also inhibit the growth of aerobic microorganisms, which contribute to decomposition and heat generation. Compaction increases the density of the fuel pile, minimizing air flow through the pile, which further limits oxygen supply and reduces the rate of heat loss. This helps to maintain a more uniform temperature within the pile, preventing localized hot spots that could lead to ignition. Effective compaction, therefore, significantly lowers the risk of spontaneous combustion, improving the safety and stability of biomass fuel storage.