A multi-scale, interdisciplinary study on the kinetics and socio-economic broader impacts of biomass pyrolysis is proposed. This research will bring together five disciplines; Chemical and Civil Engineering, Chemistry, Sociology and Agriculture. Most experimental techniques focus on meso-scale (mg) or larger quantities of raw material and mostly ignore external and internal transport conditions of the sample. The PIs propose a unique experimental technique and to introduce a Multiple Variable Control Volume Reactor (MVCVR) concept. In combination with technology for producing individual micro-spheres of biomass, the PIs propose to utilize the MVCVR to independently control the particle-related (intra-particle) and homogenous- related (extra-particle) transport phenomena and associated reactions, thereby making it possible to independently observe the two processes. A series of experiments are proposed wherein model compounds (e.g. levoglucosan and other carbohydrates), separated components (i.e. cellulose, hemicellulose, and lignin) and whole biomass are studied in an effort to understand the extent to which pyrolysis occurs within condensed phase intermediates and the homogeneous gas phase. The PIs also propose to introduce a new multi-scale modeling platform based on kinetic cellular automaton (KCA) and to demonstrate the applicability of this robust modeling strategy for simulating microstructure evolution in pyrolyzing biomass. Molecular-scale computational strategies will be used in parallel to supplement experiments and validate mechanistic hypotheses for up-scaling to KCA.
The data collected in this research will contribute to the scientific and engineering advancements currently being sought globally for the expanding biofuels industry and development of associated technology for direct thermochemical conversion of biomass-to-liquid fuels (BTL) and chemicals. Such will be elements of tomorrow?s integrated biorefineries (biochemical and thermochemical conversion under one roof) currently at the pilot and demonstration stages. For this reason the proposed work will focus on pyrolysis of whole biomass from crops with significantly reduced agricultural input requirements and residues, so as not to compete with agriculturally demanding food crops, such as corn and oilseeds.
The PIs will integrate elements of socio-economics and to provide a unique PhD experience that will greatly broaden the impact of this effort. The PIs also will include undergraduates as an integral part of the research team along the critical path. A major goal of the project is to communicate with, and gather information from, farming communities in central Tennessee. This element of the proposed research focuses on documenting and understanding the perceptions of the farming community regarding the possibility of allocating local farmland for growing energy crops. Information such as: amount of local farming land, common farming practices in terms of tillage, type of crops grown, amount of crop residues, and whether farmers are willing to grow dedicated energy crops (e.g., switchgrass), use their poor-quality crops for energy conversion, or whether they are willing to participate at all, will be gathered. The broader impacts of such an activity, while regionally-specific, are fundamental for the overall success of a sustainable biofuels industry. For the transition from a fossil resource- to a bio resource-based economy to happen, a well-informed and educated public is critical. Biopyrolysis-based fuels and chemicals research provides many unique opportunities for vertically integrated educational activities.
