Nick Nagle. October 1st, 2015

Transcription

1 Cost Reduction for Algal Biofuel Production Through Development of Novel Biorefinery Concepts Algae Biomass Summit Nick Nagle October 1st, 2015 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

2 Todays Talk Eric Knoshaug- Poster #107 Phil Pienkos presentation on Friday Three B s Bioeconomy, biorefineries and biomass Evolving parallel pathway: For both aquatic and terrestrial platforms Transitioning away from a single fuel focus Challenges for both types of biomass Cost Specifications Constraints Present one potential pathway to reduce algal feedstock cost, an early biorefinery model 2

3 The Bioeconomy- where does algae fit? A 2012 release by the U.S. Biotechnology Industry Organization placed the national value of the Bioeconomy at $1.25 trillion 1. The European Commission (2014), estimated that the Bioeconomy is worth over $2.7 trillion, providing 20 million jobs Feedstock and accounting for 9% of total Dependent employment in Bioeconomy report by Duke University for USDA

4 A feedstock perspective- cost and variability How to get a 10X Cellulose to Algal lipids to Feedstock type Corn to Cellulose ethanol to reduction Algae in ethanol to feedstock ethanol biodiesel cost? renewable diesel Cost ($$/ton (US) $ $ Volume Feedstock $1090? cost Yearly production billion gal/ 150 million gal/yr. Feedstock cost Volume?? yr. Conversion Conversion Conversion Enzymatic Dilute acid/ process process HTL, CAP, solvent process Ammonia Products Products extraction, In-situ esterification Potential products Ethanol, DDG, corn oil Ethanol, heat and power from lignin, organic acids, corn oilspotential hydrocarbon blendstock? FAMES, renewable diesel, methane, succinic acid, adipic acid, epoxides 4

5 Variability in terrestrial biomass-challenge for biorefineries Frequency Frequency Total Carbohydrates Corn Stover Corn Cob Miscanthus Wheat CS Minnesota CS Nebraska Sample number 59% %Glucan & %Xylan Carbohydrat e specification Frequency ! Integrating the needs & requirements of BC conversion with limitations (variability) of biomass! Cost and specification constraints for feedstocks % specification %Ash Total Ash Corn Stover Miscanthus Wheat Switchgrass Obtained from Garold Gresham, Idaho National Laboratory. Presented at the 2015 Biomass Platform review 5

6 Variability in algae-both time and nutrient dependent Biochemical composition of ASU algae is both species and condition-dependent Chlorella sp. Nannochloropsis sp. Scenedesmus sp. 6 6

7 Pathway for biorefineries using aquatic feedstocks Reduce overall costs for bioconversion (feedstock) - Processes that enhance/increase the value of algal biomass increases potential for project success Strategy is to employ an alternate process for fractionation and multiple product recovery from algal biomass Recovery of protein, carbohydrate and lipid components Low severity, pressure and no enzyme addition required Demonstrate production of well characterized, commodity based products Common metric for comparison of product yields 7

8 GGE- Common metric for comparison-fuel yields per ton (US) of algae resulting from fractionation

9 Combined Algal Processing (CAP) Makeup water (fresh water pipeline) CO2 (flue gas pipeline) Algae Growth Flocculent Settling DAF Recycle water Centrifuge Dilute Acid Hydrolysis Sugar Fermentatio n Fermentation product Recycle nutrients (optional) Product Purification Solvent Extraction Protein Residue Utilization Raw oil Residual Biomass Ethanol or Hydrocarbons Hydrogen Offgas Upgrading (hydrotreater) Coproducts (optional) Naphtha Diesel Makeup nutrients Yields and recoveries from unit operations 9

10 Pretreatment and fermentation of algal biomass- ethanol and FAME recovery (CAP Process) Scale-up pretreatment (100X) Zipperclave reactor High solids (20% w/w) Evaluate whole slurry fermentation of prt samples Ethanol production as a proxy for co-product production Ethanol recovery FAME recovery - Hexane extraction of prt solids FAME Recovery Pretreatment of Algae Shake-Flask Fermentation Simulated Distillation 10

11 Key results from experimental work Sugar release from pretreatment Increased to ~85% (monomeric) Oligomer production (7%) No additional nitrogen needed Maximum ethanol in 18 hr Ethanol titer of 2.5% No impact on FAME recovery after ethanol recovery Oil extracted from algae is suitable for upgrading via HDO " No need for degumming Sample Final Yields Ethanol Process Yield FAMEs Extractio n Yield Slurry + YP 82% 87% Slurry YP 85% 86% Sugar 90% nd Control Using pretreated and neutralized ASU Scenedesmus acutus 11

12 Conclusion-significant cost savings by valorizing algal sugars and lipids Pretreatment Solids loading (wt%) 20% Acid loading (wt% vs feed liquor) 2% Fermentable sugar release 74% Carbs to degradation products 1.50% Fermentation Fermentation batch time (hr) 18 Sugar diversion to organism seed growth 6% Fermentable sugar utilization 98.5 % Lipid Extraction + Upgrading Solvent loading (solvent/dry biomass ratio, wt) 5.9 Total convertible lipid extraction yield 87% Polar lipid impurity partition to extract <11.5% Hydrotreating RDB yield (wt% of oil feed) 80% Hydrotreating H 2 Consumption (wt% of oil feed) 1.70% Fuel Yields Renewable diesel blendstock (RDB, % of biomass DW) 29.2 Renewable diesel blendstock fuel yield (GGE/ton) 95.5 Ethanol (% of biomass DW) 14.9 Ethanol fuel yield (GGE/ton) 30.9 Total gasoline equivalent fuel yield (GGE/ton)

13 Questions? Thank You! Acknowledgement Technical assistance by Deborah Hyman, Andrew Lowell and Holly Smith. Drs. John McGowen and Thomas Dempster (AzCATI, ASU, Mesa, AZ) provided the biomass. This work was supported by the U.S. Department of Energy, Daniel Fishman and Christy Sterner at the Biomass Energy Technology Office (BETO)

14 FAME%purity%and%recovery%after%fermentation%with%ethanol%recovery%by%rotary%evaporation%or%by%using% simulated%distillation % Process% Fermentation%condition% EtOH%removal% FAME%purity*% *Theoretical%mass%of%fatty%acids%recovered%in%extract%divided%by%measured%mass%of%extract%% (%)% FAME%recovery% PAP% Lipid%extraction%prior%to%fermentation% EE% 97.8±0.5% 84.9±1.6% CAP% PAS%+%YP%(flask)% Rotovap% 100.3±0.8% 84.3±2.7% CAP% PAS%+%YP%(flask)% Distillation% 95.1±1.1% 82.5±0.7% CAP% PAS%E%YP%(flask)% Distillation% 95.7±0.5% 82.2±2.3% CAP% PAS%+%YP%(fermenter)% Distillation% 98.8±0.5% 86.4±2.6% CAP% PAS%E%YP%(fermenter)% Distillation% 98.5±1.2% 87.0±2.6% (%)% 14 14

15 Algal biomass to replace the whole barrel Gasoline Diesel Jet fuel Billion Gallons/yr. 1.3B tons of cellulosic biomass = ~ 130B gallons ethanol = ~ 87B gallon gasoline equivalents (GGE) www1.eere.energy.gov/biomass/ pdfs/billion_ton_update.pdf o Cellulosic biomass may only meet 40-50% of future fuels o Land required for additional biofuels may be limited o Projected fuel demand requires high productivity feedstocks o Algae have potential to produce 57B gallons on 166,000 miles 2 Sources: Weyer et al., 2010; Mascarelli et al., 2009; Wigmosta et al., 2011, Davis et al.,

16 Algal Lipids and Carbohydrates Element HL CZ HC CZ HL SD HC SD HL NC Carbon Hydrogen Nitrogen Oxygen Sulfur Phosphorus <0.001 <0.001 < NC: Laminarin CZ: Starch SD: Glucomannan 16

17 CAP process with succinic acid coproduct Producing succinic acid using C6 sugars Media using MgCO 3 5% CO 2 addition Proof of concept experiments Organic Acids 17

18 Algal Biomass Valorization Primary and co-product components of algal biomass identified Focused on select strain relating to BETO projects demonstration: Chlorella vulgaris Scenedesmus acutus Nannochloropsis granulata Link to Algal Biomass Conversion for pretreatment susceptibility for combined carbohydrate and lipid-based fuels Compatible co-products based on oleochemistry of novel lipids, carbohydrate isolation and amino acid valorization Standard method development and implementation across ATP 3 projects Biomass components: Wt % Product Raw Biomass 100% Food/Feed products Lipid (fatty acyl) 31% Diesel fuel Polyunsaturated fatty acids 3-4% Epoxies, polyols Branched chain fatty acids ~1% Fuel additives, surfactants Hydroxy fatty acids ~1% Surfactants, biopolymers Phytol 3-4% Surfactants, fuel additive Triglycerides 8-53% Biopolymers, coatings, Rubber Fatty alchohols ~2% Surfactants Sterols 2-10% Surfactants Glycerol 5% Di-acids for nylon production Carbohydrate monomers 25% Fermentation products Alginate ~10% Alginate additives Starch 5-40% Starch-derived bioplastics Protein 19-40% Thermoplastics Amino acids/peptides 19-20% Polyurethane 18

19 Number of potential conversion process to access value in cellular components Characteristics Low energy input- including recycle Effective in an aqueous matrix Removal of 90%+ of target compound Non-toxic Solvents have defined and known characteristics Minimal safety issues- i.e. solvent storage Species agnostic Ability to recycle inorganic constituents Potential Processes Solvent extraction-single, binary solvent systems Mechanical disruption i.e sonication, grinding Cell lysis Hydrothermal liquefaction In-situ transesterification Enzymatic hydrolysis Excretion (Algenol) Super or sub critical extraction (CO2) Rapid depressurization 19