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History and economics of cellulosic ethanol. Thomas Jeffries Specialized Library Association Chicago, Illinois July 17, 2012 . If we are to survive as a society we must find a way to convert our fossil energy capital into the means for renewable energy income. R. Buckminster Fuller.
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History and economics of cellulosic ethanol Thomas Jeffries Specialized Library Association Chicago, Illinois July 17, 2012
If we are to survive as a society we must find a way to convert our fossil energy capital into the means for renewable energy income. R. Buckminster Fuller
Biofuels have been under development for 200 years • Ethanol production from wood is much older than many think. • The chemistry has not changed. • Biotechnology has provided new impetus. • Emphasis increased during wars and times of fuel shortage.
Earliest attempts - 1819 • Henri Braconnot (1819) treated wood with cold 91.5% sulfuric acid, and fermented the sugar • French chemist elected member of the Paris Académiedes Sciences in 1823 Braconnot, H. 1819. Gilbert's Annalen der Physik, 63:348-371
Commercialization in Europe - 1855 • Arnould (1854) used 110 parts of concentrated sulfuric acid per 100 parts of wood and obtained 80 to 90% of wood in solution • Melsens (1855) used 3 to 5% sulfuric acid under pressure at 180°C • Pelouze (1855) erected a factory for the recovery of ethanol from wood in Paris Von Demuth, R. 1913. Zeitschr. F. angewChemieAufsatzteil 1913, 26:786-792
The Simonsen process (1894-1898) • First comprehensive examination of engineering parameters • Used dilute acid under high pressure • 15 minute hydrolysis, 0.5% sulfuric acid, 9 atm steam (≈180°C). • Yielded 26.5% sugar on a dry wood basis • Produced 7.6 L ethanol/100 kg wood
Kressmann studied dilute acid hydrolysis at FPL from 1910 to 1922 • Need for ethanol in synthetic rubber synthesis • Excess wood residues accumulated at sawmills ($0.50 per ton) • Raw material cost was ≈ 2 cents per gallon of ethanol. • Sugars from softwoods were about 70 percent fermentable while those from hardwoods were 30 percent fermentable by yeast.
First US commercialization in 1910 by the Standard Alcohol Company • Built a cellulosic ethanol plant in Georgetown, South Carolina to process waste wood from a lumber mill • Later built a second plant in Fullteron, Louisiana • Each produced 5,000 to 7,000 gal ethanol per day from wood waste • Both were in production for several years Robert Rapier Sep 10, 2009 SherradEC & Kressman FW (1945) Review of Processes in the United States Prior to World War II. Industrial and Engineering Chemistry 37(1):5-8
Problems with pentoses and sugar degradation • Foth noted in 1913 that the unfermentable sugars in hydrolysates mainly come from pentosans • The pentosans are completely converted to pentoses in the first cook • Glucose was degraded by acid at high temperatures Foth, G. 1913. The recovery of alcohol from wood. ChemikerZeitung 37(120), p. 1221
From 1916 to 1922, FPL took acid hydrolysis to the pilot scale Evaporator, Condenser Hydrolyzer Settling tank, Single effect evaporator, Hydroextractor
These findings led to the percolation process • Hemicellulosic sugars (xylose , arabinose) are hydrolyzed rapidly – but then break down in the acid • Cellulosic sugars (glucose) are hydrolyzed more slowly and are more stable • Use a percolation process with rising acidity and temperature to extract
Madison Wood Sugar process - 1943 Developed in response to need for ethanol for the synthesis of synthetic rubber. Based on the Scholler process in which dilute acid is percolated over a bed of wood chips. Differs in that dilute acid is percolated initially at a lower temperature then at progressively higher temperatures until only lignin remains. Sugars are collected in a series of tanks, neutralized with CaO and fermented.
Following World War II, scientists modified the German Sholler process for use in the United States J.A. Hall directed pilot plant studies at the Dow Chemical Company plant in Marquette, Michigan and Vulcan Copper and Supply Co. at Cincinnati Ohio. Designed a pilot plant to produce 11,500 gal of ethanol/day (4 million gallons/year) Based on Douglas fir (lowest xylan) 0.4 to 0.85% sulfuric acid 6 hour hydrolysis; 8:1 L:S ratio 50 to 150 psig; 298-366°F Yield of 52 gallons per ton (2% beer) Development of the Scholler process
Vulcan Wood to ethanol plant, Springfield Oregon, 1945 • Designed by Ray Katzen Operated by Jerry Saeman • “The plant did run and made ethanol but had lots of problems.”… “Low concentration of sugar; lots of organic matter ran down the river; no alternative to that…” • Jerome Saeman, May 1, 2003 • Tars, calcium sulfate made a hard scale and lining in pumps and valves requiring cleaning and maintenance • Ray Katzen, May 6, 2003 Constructed in 1944 operated until 1946: met target of 15,000 gal/day, 50 gal per ton
Wood to ethanol plant, Springfield Oregon, 1945 Interior Arial view
History doesn’t repeat itself… But it rhymes… • “To render automotive transportation independent of fuel imports and to produce domestically this fuel in the desired quantities, are the questions to be faced from the national point of view” -- Meunier 1922 • 1 bushel of corn yielded 2.4 gal EtOHin 1922 • Cost about $0.27/gal prior to WWI • Today one bushel of corn yields 2.75 gal EtOH • Costs about
We have made much progress with cellulosics • One ton of sawdust yielded about 12 to 20 gal EtOH/ton in 1922 • “If the manufacturing cost of producing ethyl alcohol from wood can be reduced to the same figure or nearly the same figure as that for making it from grain or molasses, there will be a large margin in favor of producing the alcohol from wood waste.” -- F.W. Kressman, USDA Bulletin No. 983, 1922, p. 2. • Today, one ton of sawdust could yield ≈70-90 gal of ethanol • The maximum theoretical yield is 110-140 gal
Two paths to cellulose saccharification Jerry Saeman 80th birthday 1996 Elwin Reese at age 62 1973
Enzymatic saccharification of cellulose • Reese, Siu and Levinson - 1950 • Cellulase is not a single enzyme but a complex • C1, Cx hypothesis (later replaced with endo/exo) • Reese organized and chaired an ACS symposium in Washington, DC on cellulase in 1962 • Katz and Reese produced 30% glucose from 50% cellulose in 1968 • Second ACS symposium on cellulase in Atlantic City 1969 • Natick symposium on “Enzymatic Conversion of cellulose 1975
Kendall King Virginia Polytechnic GeofferyHalliwell Rowett Res. Institute KazutosiNisizawa Tokyo University Karl Erick Ericksson Swedish Forest Products Laboratory Keith Selby Shirley Institute Ellis Cowling Yale School of Forestry Nobuo Toyama Miyazaki University Tarun K. Ghose Indian Institute, New Delhi Mary Mandels Natick Lab Early contributors to cellulose enzymatic saccharification
Development of Trichoderma reesei • QM6a first isolated from deteriorated shelter from Bougaineville Island at the end of WW2 • Originally identified as T. viride; in 1977 recognized as T. longibrachiatum named T. reesei by Simmons in 1977 • Produces a complete extracellular cellulase complex • Scheduled for complete genome sequencing by DOE in 2003 QM6A Linear accelerator UV QM9123 M7 1969 1976 nitrosoguanidine Linear accelerator QM9414 NG14 1971 1977 UV -Kabicidin UV TK041 C-30 1977 1978 UV UV -Kabicidin MCG77 MCG80 1977 1980
Development of hyper secreting strains • Bland Montenecourt and Doug Eveleigh developed RutC30 • Looking for carbon catabolite resistance - discovered hyper-secreting strain • Used oxgall extract and phosphon D as colony restriction agents • Blocked phospholipid production
Discovery of pentose fermenting yeasts • Wang and Schneider - NRC, Canada • Fermentation of D-xylulose (1980) • Clete Kurtzman - USDA, NRRL • Fermentation by P. tannophilus (1981) • C.S. Gong - Purdue University • Candida sp. Mutant (1981) • Tom Jeffries - FPL • Aerobic conversion by C. tropicalis (1981)
The virtual community -1981-1982 • First international computer conference on biotechnology for fuels and chemicals; Organized through IEA • One of the very first computer conferences. • Initiated by Swedish innovator; coordinated by John Black, University of Western Ontario • Brought together researchers from around the world to exchange information on bioconversion for renewable fuels and chemicals • Sweden, Canada, Japan, United States, Soviet Union, India, France, Mexico, Brazil (et al.)
Metabolic engineering - 1984 • Lonnie Ingram • Metabolic engineering of Escherichia coli • PET operon -- from Zymomonas mobilis • Min Zhang, Steve Picataggio • Metabolic engineering of Z. mobilis • Pentose metabolic genes from E. coli
Accelerating forces • Enzymes from uncultured organisms • In-vitro recombination • Directed evolution • Pathway optimization • Genome-wide expression analysis • Metabolic modeling • Petroleum prices
Average in 2011 - $111 Collapse of oil cartel 1980-86 Iranian hostage Crisis 11/79-1/81 Arab-Israeli Conflict 1973 Peak oil 2005? Source: U.S. Energy Information Administration Annual Energy Review, Table 5.21. ¹ Composite of domestic and imported crude oil. ² In chained (2005) dollars, calculated by using gross domestic product implicit price deflators. See "Chained Dollars" in Glossary.
Global warming What are the drivers?
The greenhouse effect has been recognized for 185 years • Joseph Fourier discovered greenhouse effect in 1827 • John Tyndall discovered in 1861 that H2O and CO2 were largely responsible • Svante Arrhenius showed the role of CO2 in 1896 and he and Chamberlin recognized the feedback effect with water by 1905
Projected surface temperature of the globe in 150 years • Nine of the world's 10 warmest years since records began were in the 1990s, including. • Temperatures in the 1990s were 0.33 C higher than in 1961-90 and 0.7 C higher than those at the turn of the century
We are already seeing the effects of global change • Each decade • Spring comes 5 days earlier • Animal and plant ranges move 6 km further north • Ice thinning in arctic and alpine glaciers • Vegetation changes in arctic
Regional emissions commitment from existing energy and transportation infrastructure Regional emissions normalized by regional population Regional emissions normalized by regional GDP Future CO2 Emissions and Climate Change from Existing Energy Infrastructure Steven J. Davis, et al. Science 329, 1330 (2010)
Global emissions of CO2 have an intergenerational effect The last and the current generation contributed approximately two thirds of the present day CO2-induced warming. Global mean temperatures would increase by several tenths of a degree for at least the next 20 years even if CO2 emissions were immediately cut to zero. Friedlingsteinand Solomon, 2005 PNAS 102(31):10832–10836 Solid line shows contribution to CO2 by each “generation” continuing at same rate Dotted line shows contribution if CO2 emissions were immediately stopped
CO2 is rising at a faster rate than seen in 400,000 years Domestication Of first plants
Biofuels can reduce CO2 production • Ethanol, methane and biodiesel are the most immediate bioenergy sources • Ethanol and biodiesel recovered in processing • Methane recovered from feedlot operations • Greatly reduces CO2 emissions
Summary of energy efficiencies Source: Minnesota Department of Agriculture
Biofuels account for ≈7% of the US automotive and light truck fuel supply • >14 billion gallons of ethanol/yr • Virtually all derived from grain • Ethanol can be blended at up to 10% by vol. • Has only 2/3 the energy content of gasoline
Production of ethanol from corn is reaching unsustainable levels
Cellulose to ethanol reduces CO2 emissions CTL = coal to liquids; GE = grain ethanol; CE = cellulosic ethanol; BTL = biomass to liquids; Gas = gasoline
Isobutanol could provide 12% of US automotive and light truck fuels • > 14 billion gallons of ethanol annually • Virtually all derived from grain (corn) • Ethanol can be blended at up to 10% by vol. • Has only 2/3 the energy content of gasoline • Equivalent to 7% • Isobutanol can be blended at 16% by vol • Has ¾ the energy content of gasoline • Production from cellulosics is essential for market expansion • Domestic biomass resource is sufficient
Wheat straw and forest residues are potentially the most economical feedstocks Implicit subsidy required for cellulosic ethanol at $111/bbl oil WTA = willing to accept; WTP willing to pay Source: National Research Council, 2011 Renewable Fuel Standard (prepublication)
The US produces large amounts of biomass annually • Basic advances are needed in cellulase saccharification and biocatalyst research • More funding for basic energy research is desperately needed • “Competitive funding for basic research in plant biology by all federal agencies totals only about 1% of the National Institutes of Health’s budget” • Chris Somerville Science 312:1277 (2 JUNE 2006)
Barriers to commercialization • Cellulose is recalcitrant and requires large amounts of enzymes to produce sugar • Lignin occludes polysaccharides and inhibits enzymatic hydrolysis of carbohydrates • Energetically expensive and corrosive chemical pretreatments are required. • Yeast currently used in large-scale ethanol production cannot efficiently ferment sugars other than glucose.
Why are we doing this work? • Ethanol fuels can help alleviate global warming • Wood and agricultural residues are available • Metabolic engineering can increase ethanol production