Epsilon Open Archive

Abstract

This thesis describes the use of delayed harvested reed canary-grass (Phalaris arundinacea) as a short fibre raw material for the pulp and paper industry. This study examines the following aspects of reed canary-grass: quality, transportation, storage, refining of the raw material by dry fractionation, chemical pulping, bleaching and paper production. The delayed harvesting method of reed canary-grass produces an economically and environmentally sustainable short fibre raw material for the pulp and paper industry. The ash content and fibre properties of reed canary-grass depend on soil type and growing location. The yearly variation in fibre yield and fibre properties is also considerable. There is, however, a potential for minimising quality variations by choosing reed canary-grass varieties suitable to a specific growing location. The leaf and leaf sheath content of reed canary-grass also affects the quality of the pulp. These quality variations can be eliminated by dry fractionation, a method that removes the unwanted parts of the grass. These unwanted parts can be used as a valuable bio-fuel raw material. Transport of reed canary grass after fractionation can be improved by briquetting, a method that doubles the transport capacity of reed canary-grass compared to that of birch logs on a fibre basis. High quality short fibre chemical pulp can be produced from reed canary-grass. The whole process from grass production to pulp production has been demonstrated successfully in full scale. Bleached reed canary-grass pulp can be used in products such as fine paper and white-top liner paper.