Assessment of First-Generation Cotton Module Technology for Chopped Switchgrass

Abstract

HighlightsPhysical scale models of a first-generation cotton module builder and module loader were used to determine the dry bulk density and module integrity failures for switchgrass modules.Three switchgrass particle size distributions were created and tested for various moisture contents and module building factors, such as the number of fill layers and the number of tamps per layer.Mean dry bulk density ranged from 71.5 to 94.7 kg m-3, with slightly increased densities for a reduced knifemill particle size distribution and a narrowed particle size distribution from a forage harvester.A propensity of module integrity failures was noted among 69% of all 48 modules. Only the modules for one test condition of increased knifemill particle size distribution and six fill layers had no integrity failures among all replications for the 15 test conditions.Abstract. Physical scale models of a first-generation cotton module builder and a module loader were used to test three different switchgrass particle size distributions using various levels of moisture content, module fill layers, and number of tamps per layer. The objective was to determine mean dry bulk density of the quasi-confined biomass module and the propensity of module integrity failures during emptying from the builder and during loader operations. Model designs resembled prototypes for minimizing inadvertent module upset and reduced the required module contents by a factor of 141. Overall mean dry bulk density was 80.4 kg m-3. Mean dry bulk density increased with increased narrowness of the switchgrass particle size distribution from a forage harvester. Particle size and tamping response appeared to be a unique phenomenon that slightly affected mean bulk density. Results suggested that modules should be constructed using increased numbers of fill layers with uniform tamping of each layer with at least no skips in progressive tamper action. Overall, 33 of the 48 modules exhibited integrity failures at a rate of 69% failures. Keywords: Biomass, Dry bulk density, Logistics, Module failure, Module integrity, Particle size, Processing, Switchgrass.