Supply and value chain analysis of mixed biomass feedstock supply system for lignocellulosic sugar production

Abstract

The sustainable supply of high‐quality, low‐cost biomass feedstock to cellulosic biorefineries is still a challenge. Utilizing corn stover as the single feedstock to a biorefinery also poses a source of risk to seasonal feedstock availability, affordability, and sustainability. Implementing a year‐round feedstock switching strategy or utilizing an optimal mixture of corn stover, miscanthus, and switchgrass is demonstrated to diminish these concerns while reducing the cost of sugar production by as much as 3.8% and 13.6%, respectively, when compared to a baseline sugar price of 441.9 $ metric ton−1 (t) attributed to a fixed corn stover feedstock basis. This study determines that a mixing ratio of corn stover, miscanthus, and switchgrass of 36%, 50%, and 14%, respectively, minimizes the selling price of sugar. If miscanthus is sufficiently available in the future, its fraction could be further increased to 70% by reducing the fraction of corn stover. We find that the mixed feedstock considered in this study reduces the nutrient replacement and feedstock transportation costs and improves the quality of feedstock (determined by total carbohydrates and ash) relative to corn stover alone. Results suggest that a high‐quality feedstock with a high carbohydrate content is an important metric for consideration, beyond strictly the feedstock cost, to reduce the selling price of sugar and its uncertainties. In the future this may be supported by the increased availability of higher carbohydrate feedstocks such as miscanthus. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.

Toward net-zero sustainable aviation fuel with wet waste–derived volatile fatty acids

“…At a jet fuel selling price of $2.50/gallon without carbon intensity reduction credits, profitable VFA-SAF production can be realized at a maximum VFA feedstock production cost $1.08/gallon ($0.30/kg). This price point for VFA is comparable to recent lignocellulosic sugar production cost estimates from mixed feedstocks that range from $0.36 to 0.50/kg ( 61 ). Recent work has estimated that VFAs could be produced from brown algae via anaerobic digestion and membrane distillation at a cost of $0.38/kg ( 63 ).…”

“…Fresh, spent, and regenerated ZrO 2 catalyst material properties used for 100 h of continuous time on stream ketonization of the C 6 /C 8 VFA sample (Fig. 2 feedstocks and microbial consortia (22,61,62). Consistent with the VFA samples evaluated in this work, VFAs were assumed to be recovered neat from fermentation media in their nonsalt form with no additional pretreatment steps required.…”

“…The baseline process model scenario ( Fig. 5 A ) considered the upgrading process in isolation and utilized a VFA profile corresponding to the C 4 /C 6 sample as the starting feedstock (carbon distribution in SI Appendix , Table S3 ), as shorter chain VFAs are currently accessible from a wider array of waste feedstocks and microbial consortia ( 22 , 61 , 62 ). Consistent with the VFA samples evaluated in this work, VFAs were assumed to be recovered neat from fermentation media in their nonsalt form with no additional pretreatment steps required.…”

Supply Cost and Life-Cycle Greenhouse Gas Footprint of Dry and Ensiled Biomass Sorghum for Biofuel Production

“…24,40 The optimal biorefinery size is dependent on a number of factors, including the specifics of the conversion process and scaling factors for capital equipment, which must be weighed against the increased feedstock transportation costs for larger facilities. 40 The biorefinery is assumed to be operated 330 days per year and 24 hours per day. We allocate 12.5% of additional feedstock (for 45 days) as a safety stock to mitigate the risk of stock-outs due to inclement weather, unexpected biomass losses, and any transportation delays.…”

Production and Characterization of High Value Prebiotics From Biorefinery-Relevant Feedstocks

“…Different biorefineries will utilize different regionally available lignocellulosic feedstocks, and for a sustainable year-round operation it may even be essential to switch between feedstocks ( Baral et al, 2019 ). Hence, it is necessary to investigate the efficacy of prebiotics production from multiple sources.…”