Pressure-Refined Fiber from Low-Grade Southern Hardwoods


  • Paul H. Short
  • Duane E. Lyon


Quercus falcata, Quercus alba, Liquidambar styraciflua, Carya tomentosa, Nyssa sylvatica, pressure-refined fibers, pH, fiber bulk density, anatomy, fiber alkaline buffering capacity, extractive content, southern hardwoods


Pressure-refined fiber for medium-density fiberboard was made from five species of low-grade southern hardwoods. The fiber was evaluated for extractive content, pH, alkaline buffering capacity, ash content, bulk density, and morphology. Experimental variables included three refiner plate settings (0.064-,0.127-, and 0.192-cm) and three raw material types. These were: 1) main stem with bark for each species, 2) main stem without bark for one species, and 3) whole tree for a mixture of all five species.

Result indicated that pH, alkaline buffering capacity, and ash content were independent of refiner plate settings. Species differenes in these properties could to the subsequent fiberboard processing. Although surface characteristics were similar for all five hardwood fibers, bulk density increased and the fiber became finer as refiner plate setting was reduced. Inclusion of bark in the furnish influenced the properties of the refined fiber.


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Research Contributions