Open-air storage of fine and coarse wood chips of poplar from short rotation coppice in covered piles. (December 2015)

• Record Type: Journal Article
• Authors: Lenz, Hannes; Idler, Christine; Hartung, Eberhard; Pecenka, Ralf
• Is Part Of: Biomass and bioenergy. Volume 83(2015:Dec.)
• Page Start: 269
• Page End: 277
• Publication Date: 2015-12
• Subjects: Short rotation coppice -- Poplar -- Wood chip -- Storage -- Drying -- Dry matter loss; Biomass energy -- Periodicals; Biomass -- Periodicals; Energy-Generating Resources -- Periodicals; Bioénergie -- Périodiques; 333.9539
• DOI: 10.1016/j.biombioe.2015.09.018
• Languages: English
• ISSNs: 0961-9534

Abstract

Abstract: The cultivation of short rotation coppices (SRC) on agricultural land represents an economically and environmentally promising option for sustainable provision of bioenergy. Not only the further development of efficient harvesting machinery, but also the development of harvest-optimised storage systems are necessary to implement cost-efficient cultivation and use strategies for SRC in practice. The storage of fine wood chips from poplar harvest with a forage harvester results in high dry matter losses of up to 25%. Tractor-mounted mower-chippers can harvest coarse wood chips that might possess more favourable storage and drying properties. The main objective of the current research project was to develop and perform a storage experiment in which the storage behaviour of fine and coarse wood chips could be examined and compared in detail over a period of nine months. In this experiment two covered storage piles (height 3.5 m), with over 500 m 3 fine and coarse wood chips respectively, were examined under practice scale conditions in Germany. After nine months of storage the fine chips in the core of the storage pile had dried to a moisture content of 34% with dry matter losses of 22%. Coarse chips, on the other hand, achieved a moisture content of 29% and dry matter losses of 21% in the same period. The maximum moisture content of 40% required by heating plants in practice is achieved by fine chips after 6.5 months and by the coarse chips already after 3.5 months. Highlights: The influence of chip size on storage of poplar wood was examined in detail. The time profile of temperature, loss, moisture, heating value and gas concentrations was determined. The examinations were conducted on practice scale storage piles (>500 m 3 each). Coarse and fine chips showed comparable dry matter losses after 9-months storage. Coarse wood chips dried faster than fine chips in the first 4 months of storage.