Influence of Permeability on Pulping Behavior of Tropical Indian Hardwoods
Keywords:Hardwoods, permeability, diffusion, composite permeability, suitability indices, wood structure, pulping
In this paper, an attempt has been made to correlate pulping of six tropical Indian hardwoods with their permeability and penetration behavior.
A poor correlation existed between pulping suitability indices and directional permeability. Pulping suitability indices were found to be poorly correlated even with the composite permeability of wood, indicated by loading of cooking chemicals into wood under pressure. Composite permeability of wood was found to have a good correlation with pulp yield. High composite permeability, an index of good penetration of the cells, always resulted in lower yield losses, e.g., in udal and kokko. A medium permeability resulted in medium yield (maharukh). A poor composite permeability resulting from poor penetration of the cells, despite high gas permeability in some cases (chilauni, eucalyptus, toon) resulted in higher carbohydrate losses.
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