High Yield Pulping of Hybrid Larch: Effects of Process and Operating Conditions on the Fibers Structure, 2000 Pulping / Process & Product Quality Conference Proceedings

R. Lanouette, M. Diamond--Hybrid larch represents an interesting source of long fiber due to its growth rate and its resistance to diseases. Unfortunately, it also brings some problems in high yield pulping processes, which have to be overcome. The objective of this study was to explore some possibilities in order to improve the quality of high yield hybrid larch pulps. Study shows that alkaline peroxide thermomechanical pulping is helpful to control the amount of extractive content, to reduce the specific refining energy and increase the overall quality of the resulting pulps. In using alkaline peroxide process or a combination of extraction stage and this process, we can obtain a quality of pulp close to black spruce target values. These processes require respectively 3 and 4% hydrogen peroxide. Related cost must be taken into account in a further implementation of the use of hybrid larch as furnish. The related transportation cost should be reduced since hybrid larch arboretum might be found close to the mill. No formal evaluation of these costs has however been done in the present study.