Title:
Pelletisation of Cereal Straws as a Source of Energy after Specific Comminution Processes.
Author(s):
Narra, S., Glaser, C., Gusovius, H.-J., Ay, P.
Document(s):
Paper
Abstract:
Utilization of the agricultural residues (straw) is often difficult due to their uneven and troublesome characteristics and also due to their low density (40 to 120 kg m3) including baled density. This drawback can be overcome by means of densification, i.e. compaction of the residues into products of high density and regular shape. The higher bulk density and higher energy density results in lower transportation costs and higher energy efficiency. Pelletisation of cereal straws (Rye straw and Wheat straw) requires a product specific size reduction. The product specific size reduction was achieved with the help of two different communition units (impact mill and twinscrew extruder). However, the moisture content is an important parameter in the pelletisation and also with respect to the energy characteristics. The pellets are prepared with increasing water contents and through which an optimisation of water content in the pelletisation process has been achieved. The results of the communition unit’s impact mill and twinscrew extruder are discussed based on a detailed particle size characterisation (particle size and shape). Besides the high calorific value the main pellet quality parameters such as mechanical stability, abrasion resistance and further combustion technical characteristics have been investigated and verified with the existing norms (DIN 51731, Ö NORM M 7135 and DINplus). The particle size characteristics indicate an ideal distribution of the particles for the combustion in boilers / furnaces. The durability and the mechanical stability of the pellets communited with the twinscrew extruder were comparatively better then the pellets prepared after communiting with impact mill. Particle size characteristics, abrasion values and the strength characteristics showed a good corelation. The pellets displayed optimal combustion characteristics. The present work also discusses the impact of additional components (binders, adhesives and additives), which assure the necessary binding and simultaneously increase the calorific value.
Keywords:
wheat straw, rye straw, agricultural residue straw, straw pellets, solid biofuels
Topic:
Fuels from biomass
Subtopic:
Pellet production processes
Event:
18th European Biomass Conference and Exhibition
Session:
OC5.1
Pages:
1585 - 1591
ISBN-13:
978-88-89407-56-1
ISBN-10:
88-89407-56-5
Paper DOI:
10.5071/18thEUBCE2010-OC5.1
Price:
FREE
