Fermentable sugars for Biofuels

1. Fermentable sugars for Biofuels Donal F. Day Audubon Sugar Institute UNO Sept. 2014

2. Target: regionally appropriate biomass feedstocks Questions to be Answered Agricultural Are these crops suitable for production in underutilized agricultural areas (Cold tolerance)? Industrial Are the products (syrups) suitable for use by industrial partners? Financial-Environmental What is the financial baseline for producing biofuels from these crops and what are the environmental costs associated with the production? The deep south states can to produce 50% of the biofuels in the future because they have the most available land with adequate water and sun.

3. Crop choices (potential Yields) Energycane Sweet Sorghum

4. Tasks Approaches Feedstock Development Sustainable Production Logistics and processing Conversion and Refining Economics, Markets and Distribution Education Extension Crops with staggered harvests that will grow across desired range (and not compete with food crops) Low input, sustainable production Harvest, transport, effective range Conversion to sugars (syrups) suitable for jet fuel production Establishment, market, selling costs Training of potential workers for new industry Bringing stakeholders on-board

5. Developing Process Harvest Sustainable Production Deliver analyze Feedstock development Sustainability Technology development Intermediate Product Process Conversion to Fuel Economic feasibility Value to Consumer Process Indeterminate Technology development Biomass

6. Industrial Model Primary processing plants supplying centralized biorefineries Storable syrups as feedstocks Primary plants drawing on local acreage

7. Agricultural Model Staggered Harvest, Complementary Crops, producing both fermentable sugars and biomass. Sweet Sorghum July - September Energycane October -March Bagasse, syrup, woodchips, molasses, etc. April - June

8. Sustainable ProductionExperimental sites Sites were established in Louisiana in different soil types and climatic zones for growing energycane and sweet sorghum.

9. Feedstock Development sugarcane Energycane St. Gabriel (early June 2013) Energycane grows faster Than commercial varieties Energy cane- seven molecular markers have been found, four for leaf greenness and three for regrowth damage. Genetic variability was created by cross hybridization between a set of distinct species Cross pollination between sugarcane and miscanthus, F1 in field tests across Louisiana Cold tolerance testing of Energy cane in North Louisiana location Low input testing in North Louisiana One semi-commercial variety released Breeding for Cold Tolerance Molecular markers developed for cold tolerance

10. EnergyCane – Year 3 (N. louisiana June 2014

11. Sweet Sorghum Annual crop Contains, a sugar containing juice, starch containing seed heads and fiber 90-120 day crop cycle, can be grown across target region Gross structure similar to sugarcane Can be widely grown across Southern US

12. Sweet sorghum production following legume incorporation in the soil (low input testing)

13. Harvesting • Sweet Sorghum • Energy cane Weight loss- 6-7% over 72 hr. period on harvesting 3 trials, one acre lots (about 18 rows) 8 inch billets, 3 different fan speeds evaluated 7-9% weight loss over a 72 hr. period. Same design. Harvesting in October

14. Total Fossil Energy Use (LCA) Brazilian sugar cane

15. Biofuel Feedstock Production Feasibility Index Energy Cane Production Feasibility Scale 5 (75% - 100%) 4 (50% - 74%) 3 (25% - 49%) 2 (1% - 24%) 1 (no change) Feedstock Breakeven Economic Analysis

16. Processing- Demonstrate ScalabilityProduce products for industrial testing Flexible Pilot Plant: Education, Extension and Training Facility Plant operational- initial process run July 2013

17. Pilot Plant

18. Milling Sweet Sorghum Energy Cane Three runs of 5 ton lots. For two runs the whole plant was harvested, for one the seed heads and leaves were removed. Feed rate low. It was not possible to mill the clean billets because of choking (not enough fiber). Feed rate dependent on variety. Leaf removal necessary to improve efficiency. Increased power requirement due to high fiber content.

19. Power Requirements- Milling (Crop Dependent) Sweet sorghum and energycane fall at different ends for fiber. Sugarcane Energy Cane Sweet Sorghum Eiland and Clarke, 2008 ASSCT, Panama City, Florida

20. Composition Sorghum Syrup 27.1 % Water 3.5 % Potassium 46 % Sucrose 72.9 % Dissolved Solids 1.1 % Chloride 13.2 % Glucose 0.1 % S 0.1 % P 0.25 % N 0.7 % Nitrate 11.2 % Fructose 0.4 % Calcium 0.3 % Sulfate 8.4 % Ash 0.2 % Sodium 0.2 % Magnesium 0.1 % Phosphate 0.1 % Ammonium

21. Fuels Production -Virent Energy Systems

22. Composition Sorghum Syrup 27.1 % Water 3.5 % Potassium • Removal of potassium and chloride requires advanced separation techniques such as • Ion exchange • Electrodialysis • Nanofiltration 46 % Sucrose 72.9 % Dissolved Solids 1.1 % Chloride 13.2 % Glucose 0.1 % S 0.1 % P 0.25 % N 0.7 % Nitrate 11.2 % Fructose 0.4 % Calcium 0.3 % Sulfate 8.4 % Ash 0.2 % Sodium 0.2 % Magnesium 0.1 % Phosphate 0.1 % Ammonium

23. Lignocellulosic Utilization

24. Co-generation • Model developed in SUGARSTM • Extraction by diffusion • Diluted acid pretreatment for lignocellulosic conversion Annual production of fermentable sugars, excess bagasse, electric power and syrup

25. Lignocellulosic Logistics and Pre-processing StoragePile storage best for short-term biomass storage Fragmentation patterns on milling (the lower the fiber the less fragmentation) Particle size effects pretreatment rates

26. Surplus Sugars per Day (10,000 t/d) Power Bagasse can be fluidized for steam drying, increasing energy value. Fiber Composition: 40% Cellulose (C6-Glucose) & 25% Hemicellulose (C5-Xylose) Grinding Rate : 10,000 tons/day , Bagasse Production : 3000 tons/day

27. Sugars from Lignocellulose • Unlike starch (corn), lignocellulose is made of tightly bonded sugars (cellulose, hemicellulose) and lignin • The primary technical problem • is economicaccess to the carbohydrates in this matrix.

28. Idealized Process Pretreatment Syrup

29. Pretreatment Technologies As yet there is no low cost ideal pretreatment Pretreated Post -hydrolysis

30. Pretreatment Dilute Ammonia (DA) Pretreatment Sugarcane bagasse Energy cane bagasse Sorghum bagasse A C E Untreated B D F Treated SEM Images of Untreated and Treated Sugarcane, Energy Cane and Sorghum Bagasse Salvi, D., Aita, G., et al. 2010. "Dilute ammonia pretreatment of sorghum and its effectiveness on enzyme hydrolysis and ethanol fermentation." Applied Biochemistry and Biotechnology, 161 (1-8): 67-74. Aita, G., Salvi, D., Walker, M. 2011. "Enzyme hydrolysis and ethanol fermentation of dilute ammonia pretreated energy cane." BioresourceTechnology, 102 (6): 4444-4448.

31. Enzymatic sugar production Start 6 hours 3 hours 40 hrs sugar yield - 70-90% of cellulose in biomass converted to fermentable sugars

32. Other Products Butanol; Aconitic acid bioplastics

33. Immobilized Cell Columns Laboratory Small Scale-up

34. Butanol Production Comparison Research financed by Optinol LLC

35. (glucose to butanol) Product Concentration Scale-up Simplified Plant Design tentative

36. Aconitic acid is an abundant organic acid in sugarcane, energycane and sweet sorghum. • Aconitic acid ~1% on Brix solids • Found in molasses at 3-5% • Used as flavor ingredient and adjuvant (up to 300 ppm) • Similar to citric acid Aconitic acid “Green Plastic”

37. Bio-Plastics matrices from Aconitic Acid Biodegradable photolithotrophic plastics from sugarcane materials

38. Polyester from organic acid. Trans-Aconitic Acid Formulation Citric Acid Formulation Cis-Aconitic Acid Formulation The trans-aconitic acid is darker in color and contributes to the polymer color. The citric acid is a white crystalline powder forming a clear polymer with some bubbles. The cis-aconitic acid is darker in color and contributes to the polymer color.

39. Thank you Always thinking outside the box This work supported by a USDA AFRI-Cap grant (Award No. 2011-69005-30515)