40 likes | 169 Views
CRUW. COST FP1105 Workshop, Coimdra. Morphological Ultrastructural Characteristics of Fines Fraction Produced during HC and LC refining of TMP for Fundamental Understanding of Property Development. Dinesh Fernando & Geoffrey Daniel .
E N D
CRUW COST FP1105 Workshop, Coimdra Morphological Ultrastructural Characteristics of Fines Fraction Produced during HC and LC refining of TMP for Fundamental Understanding of Property Development Dinesh Fernando & Geoffrey Daniel Center for Research on Ultrastructure of Wood Fibers (CRUW) Dept. of Forest Products Swedish University of Agricultural Sciences (SLU) Uppsala, Sweden. 08 May 2014 Dinesh Fernando 1
Results and Discussions CRUW Morphological characteristics of fines produced during HC and LC refining Primary pulp fines • Similar properties between HC & LC pulps; - tensile index (~40 Nm/g), - density (398 kg/m3), - light scattering (59 m2/kg) • But with a lower energy (20%) from LC refining 40 µm HC Fines LC Fines - Arrowheads; broader fibrils - Arrow; String-like - Arrows; Flake-like A considerable differences in ultrastructural characteristics between HC & LC Fines 08 May 2014 Dinesh Fernando 2
Results and Discussions CRUW HC fines • A wide variation in the morphology; • - predominantly ribbon-type fibrils from S2 layer • - ranging from narrow string-like to broad sheet-like fibrils • - broad cellulose fibrils possess high bonding potential and explain high density and strength properties • - SL=sheet-like fibrils, LS=lamellar sheets LC fines • Marked by very narrow strings- or thread-like ribbons; - good scattering structures (1-7) - provide required porous structure (a-g) for better light scattering • Lacked broader fibrils such as LS and SL and explain lower strength compared to HC pulps 2 µm 0,5 µm 08 May 2014 Dinesh Fernando 3
Thank you ! Center for Research on Ultrastructure of Wood Fibers Dept. of Forest Products Swedish University of Agricultural Sciences Uppsala, Sweden. CRUW COST Action Workshop, Edinburgh Acknowledgments • Dmitri Gorski (now at Metso, Sweden) from Norske Skog, Halden, Norway. • Financial support to CRUW (Centre for Research on the Ultrastructure of Wood Fibers) fromVINNOVA, EkaChemicals, Holmen, SCA, Smurtfit Kappa, Stora Enso & Södra Cell is gratefullyacknowledged. 08 May 2014 Dinesh Fernando 4