Evaluation of roll designs on a roll-crusher/ crusher/splitter biomass harvester: test bench results

Abstract

Four different roll designs were evaluated on a test bench roll crusher/splitter to determine feeding and crushing efficiencies. For each design, different gap settings for the primary and secondary rolls were tested at two hydraulic cylinder pressures on the primary crush roll to determine their ability to crush and/or feed tree bolts. Seven different diameter classes (1-7 inches) and two southern species loblolly pine (Pinus taeda) and sweetgum (Liquidambar styraciflua), are used for the tests. The results of the test combinations showed that a l/2-inch primary roll gap and a 500-psi cylinder compression pressure, combined with a l-inch secondary roll gap, allowed the greatest range of material to feed through the system. A roll design with a combination of serrated and smooth-angled bars was the best overall feed roll surface. Splitting of the tree bolts had the greatest effect on increasing rate of wood moisture loss.

Citation

Ashmore, Colin; Sirois, Donald L.; Stokes, Bryce J. 1987. Evaluation of roll designs on a roll-crusher/ crusher/splitter biomass harvester: test bench results. Proceedings of the Southern Forest Biomass Workshop; 1986 June 16-19; Knoxville, TN. Muscle Shoals, AL: Tennessee Valley Authority. p. 113-116.