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Mechanical pulping process is electrical energy intensive and results in low paper strength. Biomechanical pulping, defined as the fungal treatment of lignocellulosic materials prior to mechanical pulping, has shown at least 30% savings in electrical energy consumption, and significant improvements in paper strength properties compared to the control at a laboratory scale. In an effort to scale-up biomechanical pulping to an industrial level, fifty tons of spruce wood chips were inoculated with the best biopulping fungus in a continuous operation and stored in the form of an outdoor chip...

The structures of native celluloses have traditionally been presented in terms of two-domain models consisting of crystalline and non-crystalline fractions. Such models have been of little help in advancing understanding of enzyme-substrate interactions. In this report we first address issues that complicate characterization of the structure of native celluloses particularly with respect to information that may be relevant to understanding susceptibility to enzyme action. Key among these is the fact that crystallographic models define structure primarily at the level of the unit cell while...

Wood- and nonwood-based fibers have been found to have a significant sorption capacity for ionized copper, a heavy metal commonly found in stormwater. The USDA-FS Forest Products Laboratory (Madison, WI) is conducting research on the potential of utilizing natural wood- and nonwood-based fibers in stormwater treatment. The problem with the current practice of stormwater filtration is that it requires a large area, can be very expensive, and typically does not solve the problem of fine suspended particles or dissolved pollutants. The integration of these fibers into a stormwater filtration...

Lignocellulosic materials were evaluated for their effectiveness in filtering toxic heavy metals from stormwater. Kenaf, alfalfa, juniper, and aspen fibers were used as models to evaluate the effectiveness and limitations of chemical modification and the extent of fiber degradation. Individual and mixed aqueous solutions of nickel, copper, zinc, and cadmium in various concentrations were exposed to the lignocellulosic fibers to estimate ion-exchange capacity and competition between ionic species. The potential of lignocellulosic fibers to act as filters is related to their sugar, extractive...

The efficacy of fiber length measurement techniques such as digitizing, the Kajaani procedure, and NIH Image are compared in order to determine the optimal tool. Kenaf bast fibers, aspen, and red pine fibers were collected from different anatomical parts, and the fiber lengths were compared using various analytical tools. A statistical analysis on the validity of the fiber length measurements of each method was obtained. Using this analysis, a relationship was developed between fiber length, growth, and pulping conditions.

To evaluate the effect of backpriming on in-service performance,hardboard lap siding from one manufacturing plant was exposed on two test buildings in southern Florida for 29 months. The two buildings were identical, except that one had 0.3 m (12-inch) roof overhangs without gutters and the other had gutters but no roof overhangs. Siding installation was the same on both buildings and was essentially as recommended by the manufacturer. Laboratory tests revealed that edge swell and other properties of this particular siding were much better than required by industry standards. With only one...

Polyoxometalates (POMs) are a class of delignification agents that promise to provide the basis for a new closed-mill bleaching technology. The results presented here are based on the use of Na6SiV2W10O40, which is effective in reducing the Kappa number of softwood Kraft pulp from 30 to below 10 with minimal loss in viscosity. A critical part of a viable POM process is the elimination of the organic lignin and carbohydrate-derived fragments dissolved during the delignification. To simulate a closed process, a series of pulp samples were delignified with the same POM liquor. Before each...

This report presents statistical information on production, trade, consumption, and prices of forest products in the United States. Although national statistics are dealt with for the most part, some statistics are given for regions, states, and Canada. The tables presented in this report contain information collected from industry trade associations and government agencies. Some of the tables show data that were derived from mathematical calculations, and some show conversions from different units of measurement. These data are intended for use by anyone associated with the wood using...

Recycled paper fiber recovered from our municipal solid waste stream could potentially be used in structural hardboard products. This study compares strength properties and processing variables of wet-formed high-density hardboard panels made from recycled old corrugated container (OCC) fibers and virgin hardboard fibers using continuous pressure during drying. The results show that panels made from OCC fibers had 3 times the strength and 2 times the stiffness of panels made from virgin hardboard fibers. For commercial hardboard, panels made from OCC fibers had 2.5 and 2 times the strength...

A three-dimensional structural panel, called FPL Spaceboard, was developed at the USDA Forest Products Laboratory. Spaceboard panels have been formed using a variety of fibrous materials using either a wet- or dry-forming process. Geometrically, the panel departs from the traditional two-dimensional flat panel by integrally forming an array of perpendicular ribs and face in one structure. In the literature, significant work has been conducted to model drying of two-dimensional panels, but no known work has been done on such a three-dimensional structure. In order to optimise the drying...