Evaluating the Optimal Logistics System of Biomass Feedstocks for a Biorefinery with Alternative Harvest, Storage and Preprocessing Options: A Case Study ofEast Tennessee

摘要

The development of a commercial-scale biofuel industry that uses lignocellulosic biomass (LCB) feedstock has become a major focus in the nation's renewable energy plan. However, the high costs of harvest, storage, and transportation of feedstock is one of the major challenges to the economic viability of a LCB-based biofuels industry. The objective of this study is to estimate the costs of LCB feedstocks delivered to a commercial-scale biorefinery for alternative feedstock logistic system configurations. Specifically, the potential benefits of satellite preprocessing facilities in the feedstock supply chain are analyzed. Applying a high-resolution geo-spatial industrial siting model, the total delivered cost of switchgrass handled using conventionalhay methods is compared with logistic systems using two different potential preprocessing technologies: 1) stretch-wrap balers and 2) pellet mills. Results indicate that total delivered cost of a switchgrass logistic system using a chopper with a cutter-header for harvesting and a stretch-wrap baling technology for feedstock densification can reduce costs by about 22% to 25% when compared to various conventional logistic systems using hay harvest equipment for a 50-milHon-gallon-per-year biorefinery located in East Tennessee. The savings in feedstock logistic costs contributed by this preprocessing technology could result in a reduction in ethanol production costs by $0.16/gallon to $0.19/gallon. The potential for pellet mills to density and prepare switchgrass for storage and transportation appears to be limited if pelletized feedstock is solely used for biofuels production.