Small-Diameter Trees Used for Chemithermomechanical Pulps

摘要

During the course of restoring and maintaining forest ecosystem health and function in the western interiior of the united states, many small-diameter stems are removed fro mdensely stocked stands. In gerneal, thes materials are considered nonusable or underutilized. Information on the properties of these resources is needed to help managers understand when timber sales are a viable option to accomplish ecosystem management objectives. Pulp is a logical use for this small-diameter material. In this study, chemithermomechanical pulps were prepared and evaluated from lodgepole pine and mixed Douglas-fir/western larch sawmill residue chips; lodgepole pine, Douglas-fir, and western larch submerchantable logs; and lodgepole pine, Douglas-fir, and western larch small trees. DOuglas-fir/western larch mixture and lodgepole pine sawmill residue chips obtained ocmmercially were used as the control in making comparions. CTMP prepared from Douglas-fir small trees, Doughas-fir, submerchantable trees, adn lodgepole pine small trees consumed the most electrical energy during pulp preparation, hasdd the best paper strength properties, and the poorest optical properties compared iwth the ocntrol. Lodgepole pine submerchantable logs consumed less electrical energy, had marginal strength properties, and poor optical properties. Western larch submeerchantable logs and small trees had the lowest electrical energy consumption, poor strength properties, but some of the better optical properties. The pulp prepartion procedures selected ofr western larch submerchantable logs and small trees were detrimental to the pulp and paper properties.