Cold air ventilation for cooling and drying of poplar wood chips from short rotation coppice in outdoor storage piles in Germany

In addition to the use of plantation wood for energy, wood from short-rotation plantations can also be used for the production of construction wood and fiberboard. For energy, often wood chips are produced which can be used as fuel in domestic heaters or in combined heat and power plants. Furthermore, wood chips can be processed into second generation fuel (biomass to liquid, cellulasic ethanol). Poplar wood can also be processed into wooden tubes which can be used as supporting construction elements. This process is based on compression followed by deformation while the cell structure remains intact. Such wooden tubes allow an 80% reduction of the material compared to conventional supporting wood elements. Poplar wood can also be used for MDF and HDF production. Tests at the Institut für Holztechnologie Dresden (IHD) have shown that such boards made out of poplar wood meet the DIN EN 622-5 standard with respect to strength and stiffness with very small values for thickness swelling. The formaldehyde emissions from poplar fiber plates are significantly lower compared to similar plates made out of pine wood. Poplar wood from short-rotation plantations fulfills the technical requirements for the processing of construction elements and MDF, which opens a large economic potential.

Download Full-text

Impact of Storage Method on the Chemical and Physical Properties of Poplar Wood from Short-Rotation Coppice Stored for a Period of 9 Months

BioEnergy Research ◽

10.1007/s12155-020-10231-7 ◽

2020 ◽

Author(s):

Björn Günther ◽

Nicole Starke ◽

Armin Meurer ◽

C.-T. Bues ◽

Steffen Fischer ◽

...

Keyword(s):

Moisture Content ◽

Wood Density ◽

Storage Period ◽

Wood Moisture Content ◽

Short Rotation Coppice ◽

Poplar Wood ◽

Wood Moisture ◽

Wood Processing ◽

Short Rotation ◽

Wide Range

AbstractIn addition to the use as biofuel, the utilization of poplar wood as a raw material from short-rotation coppice (SRC) became increasingly important in recent years. Because poplar SRCs are harvested during dormant season, wood storage is of particular importance to guarantee wood processing industries a continuous wood supply. The study focuses on the change of physical and chemical properties of poplar wood by the application of different storage strategies over a 9-month period. Therefore, a total amount of 60 m3 test log piles were set up in 2018 for six different storage variants: compact piles, compact piles with water sprinkling and oxygen exclusion, each with logs in bark and debarked. The effects on wood moisture content, equilibrium moisture content and wood density (ρ0) and the changes in the chemical components lignin, cellulose, hemicellulose and extracts were determined and evaluated. As expected, the wood moisture content changed in a wide range over the storage period, depending on the variant. The levels of equilibrium moisture (changes from − 4% to − 13.1%) as well as wood density (changes from − 2.61% to − 9.01%) decreased for all variants between start and end of storage. Changes in chemical composition were observed for all storage variants, which indicates microbial activity supporting the assumption that the observed mass loss is driven by wood decay. Overall, changes were more homogeneous for logs in compact piles compared to the other storage methods. Considering the weather conditions during the investigated period, the results indicate that storage in compact piles with debarked logs is the best method for the conservation of poplar wood from SRC.

Download Full-text

Selected environmental impacts of the technical production of wood chips from poplar short rotation coppice on marginal land

Biomass and Bioenergy ◽

10.1016/j.biombioe.2015.12.018 ◽

2016 ◽

Vol 85 ◽

pp. 235-242 ◽

Cited By ~ 13

Author(s):

Janine Schweier ◽

Jörg-Peter Schnitzler ◽

Gero Becker

Keyword(s):

Environmental Impacts ◽

Wood Chips ◽

Short Rotation Coppice ◽

Marginal Land ◽

Short Rotation ◽

Technical Production

Download Full-text

Drying and Preparation of Wood Chips from Short Rotation Coppice

Bioenergy from Dendromass for the Sustainable Development of Rural Areas ◽

10.1002/9783527682973.ch33 ◽

2015 ◽

pp. 447-468

Author(s):

Joachim Brummack ◽

Matthias Umbach ◽

Kay Weichelt ◽

Anja Seifert

Keyword(s):

Wood Chips ◽

Short Rotation Coppice ◽

Short Rotation

Download Full-text

Ernte und Aufbereitung von Plantagenholz | Harvesting and conditioning of wood from short-rotation plantations

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2008.0140 ◽

2008 ◽

Vol 159 (6) ◽

pp. 140-145 ◽

Cited By ~ 1

Author(s):

Werner Grosse ◽

Dirk Landgraf ◽

Volkhard Scholz ◽

Joachim Brummack

Keyword(s):

Water Content ◽

Energy Input ◽

The Self ◽

Wood Chips ◽

External Energy ◽

Self Heating ◽

Short Rotation ◽

Air Ventilation ◽

And Performance

Short-rotation plantations are harvested in cycles of three to twenty years, depending on the production aim. In contrast to the establishment and recultivation costs, the costs for harvesting and processing of the wood occur regularly. The harvesting technology should be chosen with respect to the desired outcome – logs or chips. This is crucial for the process costs as well as the possible performance. A combination of forestry harvesters and forwarders is recommended when logs will be harvested. If the wood will be used energetically, an agricultural combined harvester and chipper fitted with suitable harvesting aggregates is the best technology with respect to productivity and performance, as well as for economic reasons. For drying the wood chips, an air ventilation process based on the self-heating of freshly harvested wood chips is an effective method for drying the wood without external energy input. With this method, it is possible to reduce the water content to 30% within three months.

Download Full-text

Storage Problems of Poplar Chips from Short Rotation Plantations with Special Emphasis on Fungal Development

Acta Silvatica et Lignaria Hungarica ◽

10.2478/v10303-012-0010-7 ◽

2012 ◽

Vol 8 (1) ◽

pp. 123-132 ◽

Cited By ~ 9

Author(s):

Zsuzsanna Horváth ◽

Béla Marosvölgyi ◽

Christine Idler ◽

Ralf Pecenka ◽

Hannes Lenz

Keyword(s):

Particle Size ◽

Health Risk ◽

Dry Matter ◽

Ph Value ◽

Wood Chips ◽

Raw Material ◽

Special Focus ◽

Fungal Development ◽

Short Rotation ◽

Fungal Particles

Abstract - There are several problems in storing wood chips freshly harvested from short rotation plantations, which result in quality losses as well as in dry matter and energy losses. The factors influencing the degradation of raw material are examined in this paper with special focus on fungal development. An excessive growth of fungi is connected to dry matter losses and also to an increased health risk during raw material handling. The following factors were measured during 6 months storage of poplar wood chips depending on particle size: box temperature, moisture content, pH-value, appearance of fungi in the storage and the concentration of fungal particles in the air. The results show a close connection between particle size, temperature and attack of fungi. During the storage mesophilic and termophilic species of the genera Alternaria, Aspergillus, Cladosporium, Mucor and Penicillium appeared. The concentration of fungal particles is the highest for fine chips and decreases in bigger particles. There was a special focus on the investigation of the properties of coarse chips (G 50), which represent a good compromise between handling, storage losses and health risk due to fungal development.

Download Full-text