Practical considerations of moisture in baled biomass feedstocks

Abstract

Background: The biomass industry requires low-cost, moisture-tolerant storage solutions to preserve herbaceous feedstocks. Methodology: We examined moisture movement in storage and identified patterns of migration, as well as their impacts on moisture measurement and dry matter recovery. Baled corn stover and energy sorghum were stored outdoors in uncovered, tarp-covered or wrapped stacks, and sampled to measure moisture and dry matter losses. Results: Interpolation between sampling locations showed clear patterns of moisture accumulation and redeposition. Exposure, orientation and contact with barriers caused the greatest amount of moisture heterogeneity within stacks. Although the bulk moisture content remained in the range suitable for aerobic stability, regions of high moisture supported microbial activity, resulting in dry matter loss. Conclusion: Stack configuration, orientation and coverage methods improve moisture management and dry matter preservation.