Effects of Coproduct Uses on Environmental and Economic Sustainability of Hydrocarbon Biofuel from One- and Two-Step Pyrolysis of Poplar

Abstract

This study investigated the environmental and economic sustainability of liquid hydrocarbon biofuel production via fast pyrolysis of poplar biomass through two pathways: a one-step pathway that converted poplar via fast pyrolysis only, and a two-step pathway that includes a torrefaction step prior to fast pyrolysis. Optimization of these fast pyrolysis-based biofuel processes were investigated through heat integration and alternative uses of the coproduct biochar, which can be sold as an energy source to displace coal, soil amendment or processed into activated carbon. The impacts of optimization on the cost of hydrocarbon biofuel production as well as the environmental impacts were investigated through a technoeconomic analysis (TEA) and life cycle assessment (LCA), respectively, with two-step and one-step processing compared to fossil fuels. The TEA indicates that a one-step heat integrated pathway with the production of activated carbon has a minimum selling price of $3.23/gallon compared to $5.16/gallon for a two-step heat integrated process with burning of the coproduct biochar to displace coal. The LCA indicates that using the displacement analysis approach, a two-step heat integrated pathway had a global warming potential of −102 g CO2 equivalent/MJ biofuel compared to 16 CO2 equivalent/MJ biofuel for the heat integrated one-step pathway.

Fractionating and Purifying Softwood Kraft Lignin with Aqueous Renewable Solvents: Liquid–Liquid Equilibrium for the Lignin–Ethanol–Water System

“…With the growing push for renewable and sustainable manufacturing, the under-utilization of lignin is becoming increasingly difficult to ignore.T he value of lignocellulosicb iomass as af eedstocki sc urrently dominated by cellulose, the only component recovered in ap ulp mill and the key component of interest in ab ioethanol refinery.U nfortunately,o ver 99 %o ft he lignin generated in these facilities is not recovered, but is simply burned for its heatingv alue. [1] However,i fl arge-scale, higher-value applications for the lignin byproduct could be identified, the economic viability of biorefineries (for paper or ethanol) would be enhanced significantly.F or example, as demonstrated in recent techno-economic analyses, the conversion of lignin into higher-valueb iochemicals [2,3] or its valorization into precursors for polymers and materials applications [4][5][6] can reduce the price of bioethanol from lignocellulosic biomass to wellbelow the DOE goal [7] of $3/gallon gasoline equivalent. Nevertheless, lignin has thus far provent ob ed ifficult to valorize.T wo properties of lignin that need to be controlled, if lignin is to achieve its potential as ar enewable biopolymer,are its purity and its molecular weight.…”

“…However, if large‐scale, higher‐value applications for the lignin byproduct could be identified, the economic viability of biorefineries (for paper or ethanol) would be enhanced significantly. For example, as demonstrated in recent techno‐economic analyses, the conversion of lignin into higher‐value biochemicals or its valorization into precursors for polymers and materials applications can reduce the price of bioethanol from lignocellulosic biomass to well below the DOE goal of $3/gallon gasoline equivalent. Nevertheless, lignin has thus far proven to be difficult to valorize.…”

Economic Performance of Small-Scale Fast Pyrolysis Process of Coproducing Liquid Smoke Food Flavoring and Biofuels

“…Fast pyrolysis is a thermochemical process of biomass liquefaction by optimizing pyrolysis conditions including temperature, heating rate, and vapor resident time . It offers a promising approach to convert biomass to renewable biofuels to replace fossil fuels for environmental benefits. − On the other hand, the economic analysis has shown difficulty in achieving its economic feasibility due to the selling prices being uncompetitive with petroleum-derived fuels. − Previous studies suggested that the aqueous fraction of the pyrolysis liquid created a costly wastewater treatment burden for the conversion process. , Therefore, the valorization of the pyrolysis aqueous liquid can improve the economic performance of the biomass pyrolysis process. This aqueous liquid produced from woody biomass pyrolysis is referred to as liquid smoke, smoke condensate, wood vinegar, and pyroligneous acid in different research areas.…”

Impact of co‐product selection on techno‐economic analyses of alternative jet fuel produced with forest harvest residuals

“…13,14,15,12,16 Coproduct selection will impact the final fuel MSP. 17 Pretreatment of lignocellulosic biomass is often complex and expensive. This process must disrupt the natural crystalline structure to facilitate enzyme access to cellulose and hemicellulose for saccharification.…”