1. Modeling Biomass Conversion to Transportation Fuels Jacob Miller Advisor: Dr. Eric Larson

2. Outline What is biomass? Why is it useful? What is bioconversion? What is biomass made of? Manufacturing process Model creation: Mass, energy, and carbon balances Economic modeling, carbon and energy credits Final cost estimates

3. What is biomass? Yes No Switchgrass Corn Stover Corn Soybeans Inedible plant matter

4. Bioconversion Rubin, 2008 2

5. Components of Biomass What we care about: Cellulose, lignin, hemicellulose Alonso et al. 2012 Enzymatic hydrolysis, bioconversion to fuels Pretreatment, bioconversion to fuels Burned for electricity

6. 3 Core Processes Pretreatment: Separate hemicellulose and lignin from cellulose, depolymerize hemicellulose (in some cases) Common methods: dilute acid, steam, ammonia Hydrolysis: break cellulose up into individual glucose monomers Method: enzymes (biological catalysts) Bioconversion: converts sugars to fuel molecules Common example: fermentation of glucose to ethanol

7. Model Basis: NREL Model Davis et al. 2013 Process units altered slightly in various scenarios

8. Model Creation: Mass, Energy, and Carbon Balances Mass flows, kg/hr =Process CO 2 outlets

9. Final Cost Estimates Sample MFSP: Minimum fuel selling price Takeaway: cellulosic biofuels won’t be economical without high CO 2 taxes Plant Configurations

10. Acknowledgements Princeton Environmental Institute Dr. Eric Larson, Dr. Thomas Kreutz, Dr. Robert Williams, Dr. Hans Meerman, Maurizio Spinelli

11. Questions?

12. Economic Modeling, Carbon and Energy Credits Discounted Cash Flow Analysis External power source/replacement: Natural gas combined cycle plant CO 2 tax: $0-$100/ton

13. Components of Biomass Plant % Dry Mass Cellulose % Dry Mass Hemicellulose % Dry Mass Lignin % Dry Mass Other Sugarcane bagasse35.224.522.218.1 Switchgrass35.230.57.726.6 Corn stover34.422.81824.8 Rezende et al. 2011 Godin et al. 2013 Kumar et al. 2009

14. Carbon Capture Integration Rectisol Less expensive ($1s million capital costs) Can only capture CO 2 from pressurized sources Amine Solvent More expensive ($100s million capital costs) Can capture CO 2 from any emissions source (ex: biomass generator)