(89a) Autothermal Pyrolysis of Lignocellulose Wastes to Sugars and Other Biobased Products

The goal of this RAPID Institute project, a collaboration between Iowa State University (ISU) and Easy Energy Systems (EES), is to develop a pyrolysis-based Modular Energy Production System (MEPS) for the thermal deconstruction of lignocellulosic biomass into cellulosic sugars and other value-added products. ISU is developing several innovations in process intensification of pyrolysis that dramatically enhances the prospects for distributed processing of biomass to produce cellulosic sugars and other products. The focus of this project during Budget Period 1 include: (1) evaluation by ISU of continuous pretreatment and autothermal pyrolysis of lignocellulosic feedstock in the process intensification of cellulosic sugar production; and (2) design and construction by EES of modules for feedstock handling and autothermal pyrolysis at the 50 ton per day demonstration scale. Successful completion of these two activities will set the stage for design and construction of other modules associated with demonstrating pyrolysis-based MEPS as a viable approach to low-cost cellulosic sugar production.

Autothermal pyrolysis investigated in this project is a specific example of the more general principle of autothermal chemical processing, which balances energy demand from endothermic reactions with exothermic reactions. Autothermal chemical processing has application to other processes for which heat transfer is the bottleneck to process intensification. Although reactions that proceed to chemical equilibrium are relatively easy to operate under autothermal conditions, non-equilibrium processes, like fast pyrolysis, are more challenging to operate autothermally without adversely affecting desired product yields. Our work to date demonstrates that autothermal chemical processing has the potential to simplify reactor design and dramatically increase throughput when heat transfer is the bottleneck for a chemical process.