Evolution of New Processes and Products from Dry Grind Fuel Ethanol Processing Kurt A. Rosentrater, Ph.D. Department of Agricultural and Biosystems Engineering Iowa State University (515) 294-4019 karosent@iastate.edu 1
OVERVIEW 1. Ethyl alcohol 2. Coproducts 3. Ongoing research 4. New opportunities 5. Concluding thoughts 2
ETHYL ALCOHOL 3
Ethyl Alcohol The Fuel of the Future 1860 Nicholas Otto (b. 1832, d. 1891), a German inventor, used ethanol to fuel an internal combustion engine 1896 Henry Ford s (b. 1863, d. 1947) first automobile, the quadricycle, used corn-based ethanol as fuel 1908 Hart-Parr Company (Charles City, IA) manufactured tractors that could use ethanol as a fuel Henry Ford s (b. 1863, d. 1947) Model T used corn-based ethanol, gasoline, or a combinations as fuel 1918 World War I caused increased need for fuel, including ethanol; demand for ethanol reached nearly 60 million gal/year 1940 The U.S. Army constructed and operated a fuel ethanol plant in Omaha, NE Ethanol was extensively used as a motor fuel additive prior to the end of World War II (ca. 1933) 4
Ethyl Alcohol The Fuel of the Future The first distillation column for the production of fuel ethanol was invented by Dennis and Dave Vander Griend at South Dakota State University in 1978/1979 5
DDGS Historically Many people have asked what the fuel ethanol industry is going to do about the growing piles of non-fermented leftovers Grain distillers have developed equipment and an attractive market for their recovered grains (Boruff, 1947) Distillers are recovering, drying, and marketing their destarched grain stillage as distillers dried grains and dried solubles (Boruff, 1952) This question has been around for quite some time, and it also appears that a viable solution had already been developed as far back as the 1940s 6
DDGS Historically In the 1940s / 1950s 17 lb (7.7 kg) of distillers feed was produced for every 1 bu (56 lb; 25.4 kg) of grain that was processed into ethanol Similar to today But over 700 gal (2650 L) of water was required to produce this feed (Boruff, 1947; Boruff, 1952; Boruff et al., 1943) vs. < 4 gal. of water today 7
GRAIN ALCOHOL DISTILLERY (ca. 1947) 8
MODERN DRY GRIND PROCESS 9
1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 U.S. ETHANOL GROWTH 16000 45 14000 12000 Ethanol Production RFS Mandated Production Coproduct Generation 40 35 Fuel Ethanol (gal) x 10 6 10000 8000 6000 Feb. 2011: 204 plants, 13,771 Mg/y RFS: 15,000 Mg/y of biofuel by 2015 30 25 20 15 4000 10 2000 5 0 0 Coproducts (t) x 10 6 Year Growth of U.S. fuel ethanol industry 10
Total U.S. Energy (Btu) U.S. ETHANOL GROWTH 1.2E+17 Consumption - Fossil 1E+17 8E+16 Production - Fossil Nuclear Renewable Total Consumption 6E+16 4E+16 2E+16 0 1950 1960 1970 1980 1990 2000 2010 Year US EIA, 2011 11
U.S. ETHANOL GROWTH Crude Oil 37% Renewable 8% Nuclear 9% Solar, 1% Geothermal, 5% Waste, 6% Wind, 9% Biofuels, 20% Coal 21% Wood, 24% Hydroelectric, 35% Natural Gas 25% Since 1950s, generally 5 to 9 % of total U.S. US EIA, 2011 energy supply has been renewable 12
COPRODUCTS 13
ETHANOL COPRODUCTS Distillers Dried Grains with Solubles Condensed Distillers Solubles Distillers Wet Grains 14
Jan-80 Jan-81 Jan-82 Jan-83 Jan-84 Jan-85 Jan-86 Jan-87 Jan-88 Jan-89 Jan-90 Jan-91 Jan-92 Jan-93 Jan-94 Jan-95 Jan-96 Jan-97 Jan-98 Jan-99 Jan-00 Jan-01 Jan-02 Jan-03 Jan-04 Jan-05 Jan-06 Jan-07 Jan-08 Jan-09 Jan-10 Jan-11 Jan-12 DDGS Price ($/t) COPRODUCT PRICES 250 200 150 100 50 0 Date 15
Sales Price ($/t) COPRODUCT PRICES 450 400 350 300 250 200 150 100 50 Corn SBM DDGS 0 Jan-11 Feb-11 Apr-11 Jun-11 Jul-11 Sep-11 Nov-11 Date 16
DDGS Price Relative to (%) COPRODUCT PRICES 100 90 80 70 60 50 40 30 20 10 Corn SBM 0 Jan-11 Feb-11 Apr-11 Jun-11 Jul-11 Sep-11 Nov-11 Date 17
Price / Unit Protein ($/ t/% protein) COPRODUCT VALUES 40 35 30 25 20 15 SBM DDGS Corn 10 5 0 Jan-11 Feb-11 Apr-11 Jun-11 Jul-11 Sep-11 Nov-11 Date 18
Value ($/bu corn) DDGS Value (% of total revenue) COPRODUCT VALUES 9 25 8 7 6 5 20 15 4 3 2 1 Value of Ethanol ($/bu corn) Value of DDGS ($/bu corn) DDGS Value (% total) 10 5 0 0 Oct-09 Jan-10 May-10 Aug-10 Nov-10 Feb-11 Jun-11 Sep-11 Dec-11 Date 19
COPRODUCT RESEARCH As ethanol industry grows, supply of coproducts will grow Balance = key to sustainability Livestock producers Ethanol manufacturers 20
ONGOING RESEARCH 21
ONGOING RESEARCH Fuel vs. Food vs. Feed vs. Plastics vs. Chemicals vs. Other uses Goals: Augment current uses Develop new market opportunities Develop/optimize processes and products Improve sustainability Context: Application of physics and chemistry to biological systems Manufacturing with biological polymers: proteins, fibers, lipids 22
ONGOING RESEARCH Material handling Pelleting/densification Aquaculture Human foods Plastic composites 23
MATERIAL HANDLING 24
MATERIAL HANDLING Sieve Opening Size (mm) 2.38 1.68 1.19 0.841 Scale bar = 3.91 mm Scale bar = 2.50 mm Scale bar = 2.34 mm Scale bar = 0.987 mm 0.595 0.420 0.297 0.210 1 2 Scale bar = 0.689 mm Scale bar = 0.52 mm Scale bar = 0.36 mm Scale bar = 0.26 mm 25
0.841 Particle Diameter (mm) 1.19 Plant 1.68 2.28 MATERIAL HANDLING Carbohydrate Protein Batch 1 Batch 2 1 2 3 4 5 26 1
Mass Flow Rate (g/min) MATERIAL HANDLING z= a + bx + cy 150 140 130 150 140 130 x= AoR ( ) y = HR (-) z= MFR (g/min) 120 110 120 110 R 2 = 0.99 Error= 2.42 100 90 80 1.125 1.15 HR (-) 1.175 1.2 1.225 1.25 1.275 1.3 45 40 35 30 AoR ( o ) 100 90 80 MFR < 100 = Poor Flow 100 < MFR < 120 = Fair Flow MFR > 120 = Good Flow Good flow Fair flow Poor flow 27
Moisture Content (% db) MATERIAL HANDLING 40 35 30 25 20 15 10 5 0 40 AoR ( o ) 35 30 25 1.1 1.2 1.175 1.15 1.125 1.275 1.25 1.225 HR (-) 20 15 10 5 0 40 35 30 25 z= a + b/x + cy x= AoR ( ) y = HR (-) z= Moisture content (%, db) R 2 = 0.71 Error= 4.50 Moisture < 9.9 (Good Flow) 9.9 < Moisture < 17.5 (Fair Flow) 17.5 > Moisture (Poor Flow) Good flow Fair flow Poor flow 28
CC/Dispersibility * d/f (-) MATERIAL HANDLING 0.35 0.30 0.25 y = 3.4629x - 3.4854 R 2 = 0.8823 Plant 1 0.20 0.15 Plant 2 Plant 5 y = 2E-11e 21.531x R 2 = 0.8368 0.10 0.05 Plant 4 Plant 3 0.00 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 PBD/ABD (-) 29
PELLETING/DENSIFICATION 30
PELLETING/DENSIFICATION Mag. x 10 DDGS A Mfg B 60 200 31
Total Slack Cost per Car, SCcar ($/car) Pelleting Cost per Car, Pcar ($/car) PELLETING/DENSIFICATION 6000 5000 a $50/ton DDGS Sales Price, s $100/ton DDGS Sales Price, s $150/ton DDGS Sales Price, s $200/ton DDGS Sales Price, s 15 $/ton pelleting cost, Cop 6000 5000 10 $/ton pelleting cost, Cop 4000 5 $/ton pelleting cost, Cop 4000 3000 3000 2000 2000 1000 1000 0 0 0 10 20 30 40 50 60 70 80 90 100 Percentage of DDGS Pelleted, p (%) Resulting slack costs and costs of pelleting for each rail car due to differing DDGS sales prices and annualized pelleting cost a) breakeven occurs at points of intersection 32
Total Slack Cost per Car, SC car ($/car) Pelleting Cost per Car, Pcar ($/car) PELLETING/DENSIFICATION 1500 $50/ton DDGS Sales Price, s $100/ton DDGS Sales Price, s $150/ton DDGS Sales Price, s $200/ton DDGS Sales Price, s 10 $/ton pelleting cost, Cop 15 $/ton pelleting cost, Cop 5 $/ton pelleting cost, Cop b 1500 1000 1000 500 500 0 0 40 50 60 70 80 Percentage of DDGS Pelleted, p (%) Resulting slack costs and costs of pelleting for each rail car due to differing DDGS sales prices and annualized pelleting cost b) magnification of the intersections clearly shows the proportion of DDGS which needs to be pelleted to achieve breakeven 33
p (%) p (%) PELLETING/DENSIFICATION 80 75 70 65 60 55 50 45 40 175 150 125 s ($/ton) 100 75 50 25 14 5 6 7 8 9 10 11 1213 Cop ($/ton) 80 75 70 65 60 55 50 45 40 Percent of DDGS pelleted, p (%), required to achieve breakeven increases as both DDGS Sales Price, s ($/ton), and Pelleting Cost, Cop ($/ton), increase 34
AQUACULTURE Nile tilapia Yellow Perch Rainbow Trout 35
Relative Feed Cost ($/tonne) AQUACULTURE DDGS ~ 1/10 to 1/20 the price of fish meal 1.2 1.0 Tilapia Perch Trout FM: 1000 $/tonne FM: 2000 $/tonne DDGS: 100 $/tonne 0.8 0.6 0.4 0.2 0.0 0 20 40 60 80 100 120 % Fish Meal Replaced 36
Low-fat DDGS DDGS HUMAN FOODS Diabetic and Celiac patients High protein, high fiber, low starch 37
HUMAN FOODS Flat breads Chipathi Southern Asia Similar to tortilla Naan Northern India and near East Tandoori clay ovens ~ 650-780 F Barbari Persian Brick-lined ovens ~ 480 o F 38
PLASTIC COMPOSITES Phenolic resin & DDGS DDGS Biodegradability Durometer Hardness Density Water Absorption (mass %) (%) (mass % degraded) (Shore D) g/cm 3 (lb m /ft) 2 hour 24 hour one week 0 0.0 ± 0% 93 ± 2% 1.20 (75.2) ± 52% 0.1 ± 0% 0.2 ± 0% 0.5 ± 0% 25 8.6 ± 12% 82 ± 2% 1.24 (77.5) ± 15% 1.6 ± 1% 2.8 ± 3% 7.9 ± 8% 50 24.4 ± 10% 72 ± 3% 1.23 (77.0) ± 35% 5.0 ± 2% 13.2 ± 5% 29.4 ± 9% 75 38.4 ± 6% 68 ± 3% 1.22 (76.4) ± 41% 6.2 ± 3% 15.9 ± 8% 33.5 ± 17% 39
Relative Biodegradability Ultimate Tensile Strength, psi MPa PLASTIC COMPOSITES Polylactic acid (PLA) & DDGS 80 70 60 2000 1500 12 50 9 40% DDGS 40 1000 6 30 30% DDGS 20 500 3 10 20% DDGS 0 50% ground 35% raw 25% ground 0% white pine 0 25% raw 25% ground 10% raw 10% ground 0% 0 10% DDGS 0% DDGS DDGS Level (%) Property 0 10 20 30 40 Ultimate tensile stress (UTS) 8894 6481 4097 3385 3290 psi (MPa) (61.3) (44.7) (28.2) (23.3) (22.7) Break stress 8754 6436 3448 3051 2887 psi (MPa) (60.4) (44.4) (23.8) (21.0) (19.9) Young s modulus 270,690 304,130 278,160 251,830 305,140 psi (MPa) (1866) (2097) (1918) (1736) (2104) Flexural modulus 342,732 326,891 338,135 338,071 300,872 psi (MPa) (2363) (2254) (2331) (2331) (2074) Elongation to UTS, % 5.1 3.3 2.3 2.0 2.0 Elongation to break, % 5.4 3.4 2.8 2.3 2.2 Hardness Shore D 79 77 77 77 40 78
PLASTIC COMPOSITES 41
PLASTIC COMPOSITES 42
NEW OPPORTUNITIES 43
NEW OPPORTUNITIES Evolving processes Fractionation Biorefining / bioprocessing Anaerobic digestion Integrated systems 44
EVOLVING PROCESSES Wet vs. dry coproducts DDGS vs. DWGS Oil extraction from stillage (40-60 cents/lb) ~ 10% down to 8-9% fat Every 1% fat reduction = $3-$6 /ton finisher diet increase Jan. 2012: 47% of plants extracting oil 45
EVOLVING PROCESSES Corn oil Corn oil 46
EVOLVING PROCESSES 47
LOW FAT DDGS Properties of low fat DDGS Plant 1 Plant 2 Plant 3 Protein (%) 8.0 8.3 9.3 Protein (%) 26.0 29.9 29.0 Fiber (%) 15.0 7.9 6.2 Ash (%) 5.5 4.4 4.2 Bulk Density (kg/m 3 ) 543 571 466 470 440 446 Packed Bulk Density(kg/m 3 ) 623 650 525 543 476 499 AoR 40.5 45.5 39.5 43.5 40.0 43.0
LOW FAT DDGS 8% Fat 8% Fat
LOW FAT DDGS Removal of corn oil does not change flow properties of DDGS Biggest obstacles Variability / consistency Syrup addition Drying conditions 50
FRACTIONATION High-value components Coproducts Component Fractionation Mid-value components Low-value components 51
FRACTIONATION High-Value Animal Feed Human Foods Chemicals Neutraceuticals High-value components Biofuel Coproducts Component Fractionation Mid-value components Livestock Feed Low-value components Plastic Composites Recycling / Reuse within plant Biofuels Energy Landfill Other Intermediates 52
HIGH-PROTEIN DDGS Manufacturer Product Type of Fractionation Crude Protein Crude Fat Crude Fiber ADF NDF Ash Reference Poet Dakota Gold BPX DDGS No fractionation 28.2 10.8 7.1 10.0 26.1 4.8 Dakota Gold, 2009a Dakota Bran Pre-fermentation 14.0 8.9 7.0 8.0 38.1 5.5 Dakota Gold, 2009b Dakota Germ - Corn Germ Dehydrated Pre-fermentation 15.8 17.1 6.2 8.2 23.4 5.9 Dakota Gold, 2009c Dakota Gold HP DDG Pre-fermentation 41.0 4.0 8.1 13.0 24.0 2.1 Dakota Gold, 2009d FWS Technologies Enhanced DDGS Pre-fermentation 35.0-37.0 6.5 21.0 3.8 FWS, 2009 Renessen Enhanced DDG(S) Pre- / postfermentation 35.0-50.0 2.5-4.0 7.0-11.0 15.0-25.0 Stern, 2007 Solaris Energia Pre- / postfermentation 30.0 2.5 8.2 2.5 Lohrmann, 2006 Glutenol Post-fermentation 45.0 3.3 3.8 9.23 15.3 4.0 Lohrmann, 2006 Neutra-Fiber Pre-fermentation 6.8 1.5 17.1 0.6 Lohrmann, 2006 NeutraGerm Pre-fermentation 17.5 45.0 6.0 1.9 Lohrmann, 2006 ProBran Pre- / postfermentation 9.5 2.0 16.6 1.0 Lohrmann, 2006 53
FRACTIONATION a) Original DDGS; b) big DDGS; c) pan DDGS Big Original Pan Property Mean St Dev Mean St Dev Mean St Dev Protein 31.85 a 1.06 33.00 a 0.99 37.25 b 0.21 Lipid 8.65 a 0.07 7.95 b 0.07 7.00 c 0.01 Ash 4.70 a 0.01 4.70 a 0.01 5.00 b 0.01 Carbohydrate 54.80 a 1.13 54.35 a 0.92 50.75 b 0.21 ADF 11.60 a 0.71 12.40 b 0.57 11.45 a 0.07 NDF 34.55 a 0.49 37.80 b 0.14 29.15 c 0.21 1 54
FRACTIONATION DDGS fiber Protein: 21% Lipid: 1.7% Fiber: 52% Ash: 4.0% 55
Glucose Arabinose Succinic Acid Lactic Acid 2.27 g/l Ethanol Xylose/Galactose/Mannose Glucose Xylose/Galactose/Mannose Arabinose Succinic Acid Lactic Acid 5.59 g/l FRACTIONATION MW kda 150-250 75-100 50 37 CDS CDS Ghost Glycerol 25 20 15 10 Lane 1 2 3 4 5 6 7 8 9 10 MW kda 150-250 75-100 50 37 Thin Stillage Thin Stillage Ghost Glycerol 25 20 15 10 Lane 1 2 3 4 5 6 7 8 9 10 56
Gas (psi) BIOREFINING DDGS H 2 O Makeup H 2 O Recycle NH 3 Recycle Compressor Biomass pump mix Reactor NH 3 Makeup P Separation Treated DDGS NH 3 27 25 23 21 19 DDGS Blank Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 17 Blank 15 2/27/2008 9:50 2/27/2008 13:26 2/27/2008 17:02 2/27/2008 20:38 2/28/2008 0:14 2/28/2008 3:50 In vitro true DM digestibility (TDMD) 2/28/2008 7:26 2/28/2008 11:02 57
BIOREFINING 58
BIOREFINING 59
Methane Potential (%) ANAEROBIC DIGESTION 1.0 0.8 0.6 1% Sucrose Blank DDG DDGS Thin Stillage Whole Stillage CDS 0.4 0.2 0.0 Cumulative biogas and average methane Potential methane production 60
Anaerobic Digester INTEGRATED SYSTEMS Biofuel Refinery 61
INTEGRATED SYSTEMS 62
CONCLUDING THOUGHTS Coproducts key to economic viability of renewable fuels Many opportunities to increase value and utility Several keys to sustainability 63
THANK YOU Questions? Comments? Kurt Rosentrater Department of Agricultural and Biosystems Engineering Iowa State University (515) 294-4019 karosent@iastate.edu 64