Field-to-Fleet Webinar: How Does Feedstock Type Affect Biofuels Conversion?
The production of renewable motor fuels from lignocellulosic biomass is a key part of the U.S. strategy to ease dependence on imported oil and reduce greenhouse gas emissions. For this strategy to be environmentally and economically sound, biomass resource development and conversion technology development must be coordinated so that cost-competitive biofuels can be produced using sustainable, low-cost, and diverse feedstocks. However, the impacts of different biomass types on conversion performance (process efficiency, product quality, potential waste streams) are not well known. To this end, Idaho National Laboratory (INL), National Renewable Energy Laboratory (NREL), and Pacific Northwest National Laboratory (PNNL) are partnering to understand the ‘field-to-fleet’ implications of using different feedstocks in various thermal conversion processes, including fast pyrolysis, catalytic fast pyrolysis, hydrothermal liquefaction, hydrodeoxygenation, and gasification. We recently published results from an integrated study to produce petroleum refinery blendstocks via pyrolysis and catalytic hydroprocessing using several commercially-relevant feedstocks, including softwoods, hardwoods, herbaceous materials, and blends. The results presented here show that feedstock choice has a significant impact on multiple conversion metrics, including bio-oil yield and composition, hydrotreating yield, H2 consumption, selectivity to fuel products, and biomass carbon-to-fuel efficiency. Technoeconomic analysis was used to estimate conversion costs in a commercial process, based on a published design case, indicating that in-plant fuel production costs are also projected to vary significantly. The overall processing efficiency as a function of feedstock is examined on the basis of mass, carbon, and chemical energy of the inputs and products. It is hoped that a quantitative understanding of how different biomass types behave in various thermal processes, coupled with projected feedstock and preprocessing costs, will allow biomass resources to be well-matched with biofuels conversion processes.