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Study GuideStudy GuideBiofuel vs PetroleumBiofuel vs Petroleum--based fuelbased fuelExam questions will relate the lectures Exam questions will relate the lectures to each otherto each other–– Advantages and disadvantages of the Advantages and disadvantages of the
different fuels (methanol, ethanol, different fuels (methanol, ethanol, bioethanol, and biodiesel) and compared bioethanol, and biodiesel) and compared to petroleumto petroleum
–– How are they similar and different from How are they similar and different from each other? Make a table to compareeach other? Make a table to compare
EXAM # 2 IS ON TUESDAY NOVEMBER 30TH: Endophyte-Assisted Phytoremediation plus the three bioenergy lectures so far
Bioenergy LecturesBioenergy LecturesThTh Nov 16Nov 16-- OverviewOverviewTuTu Nov 18Nov 18-- BiodieselBiodieselThTh Nov 23Nov 23-- Bioethanol and methanolBioethanol and methanolTuTu Nov 25Nov 25-- HolidayHolidayNov 30Nov 30-- EXAM #2 (EXAM #2 (PhytoPhyto with endophytes; with endophytes; first 3 first 3 bioenergy lectures)bioenergy lectures)
Dec 2Dec 2--Ways to improve the efficiency of biofuel Ways to improve the efficiency of biofuel productionproductionDec 7Dec 7-- (cont.)(cont.)Dec 9Dec 9-- Environmental applications of trees; paper Environmental applications of trees; paper assignment givenassignment given
Dec 13Dec 13-- Final exam (75 pts) on last 3 Final exam (75 pts) on last 3 lectures (in lectures (in class for both ESRM and CFR);class for both ESRM and CFR); Paper (50 pts) is duePaper (50 pts) is due
BioethanolBioethanol
((Many of the following slidesMany of the following slides are from are from Prof. Renata Bura)Prof. Renata Bura)
OverviewOverview
What is bioconversion?What is bioconversion?Why bioconversion?Why bioconversion?Biomass compositionBiomass compositionBioconversion to ethanol processBioconversion to ethanol process–– PretreatmentPretreatment–– HydrolysisHydrolysis–– FermentationFermentation
Pros and cons of bioethanolPros and cons of bioethanolComparison to other Comparison to other biofuelsbiofuels
What is bioconversion?What is bioconversion?
General: a process which uses biological General: a process which uses biological agents (microorganisms or protein) to agents (microorganisms or protein) to transform a feedstock into desirable transform a feedstock into desirable products.products.
BioethanolBioethanolA chemical/biochemical process by which A chemical/biochemical process by which lignocellulosic materials are converted to lignocellulosic materials are converted to ethanol and other coethanol and other co--products.products.
BioconversionBioconversion
Biomass
Pretreatment
Hydrolysis
Fermentation Distillation
Ethanol
Ethanol (CHEthanol (CH33CHCH22OH)OH)
Ethyl alcohol, grain alcoholEthyl alcohol, grain alcohol–– Clear, colorless liquidClear, colorless liquid
Ethanol made from cellulosic biomass instead of Ethanol made from cellulosic biomass instead of starch cropsstarch crops--bioethanolbioethanolAdvantages of bioethanolAdvantages of bioethanol–– Domestic renewable fuel sourcesDomestic renewable fuel sources–– Reduces reliance on foreign oilReduces reliance on foreign oil–– Cleaner fuel sourcesCleaner fuel sources–– Easily produced and storedEasily produced and stored–– Increases fuel octane number for little costIncreases fuel octane number for little cost
Energy contentEnergy content
Gasoline Ethanol Biodiesel
100% 67% 86%
“We can get fuel from apples, weeds, “We can get fuel from apples, weeds, sawdust, almost anything…..sawdust, almost anything…..And it remains for someone to find how this And it remains for someone to find how this fuel can be produced commerciallyfuel can be produced commercially--better fuel at a better price than we now better fuel at a better price than we now know.”know.”
Henry FordHenry Ford
Henry FordHenry Ford
Why bioconversion?Why bioconversion?EnergyEnergy–– An alternative source of energy for the An alternative source of energy for the
transportation sector produced locallytransportation sector produced locallyAir pollutionAir pollution–– Reduction in greenhouse gas emissionReduction in greenhouse gas emissionWaste eliminationWaste elimination–– Elimination of problems with field Elimination of problems with field
burning/incineration, stockpiling, etc.burning/incineration, stockpiling, etc.Socio/economical benefitsSocio/economical benefits–– Creation of new jobs, rural developmentCreation of new jobs, rural development
Possible Possible feedstocksfeedstocks
Agricultural residues (corn stover, corn Agricultural residues (corn stover, corn fibre, wheat straw, rice straw)fibre, wheat straw, rice straw)Wood residues:Wood residues:–– Hardwood (poplar, willow)Hardwood (poplar, willow)–– Softwood (DouglasSoftwood (Douglas--fir, fir, lodgepolelodgepole pine)pine)
Paper wastePaper wasteMunicipal solids wasteMunicipal solids waste
OverviewOverview
What is bioconversion?What is bioconversion?Why bioconversion?Why bioconversion?Biomass compositionBiomass compositionBioconversion to ethanol processBioconversion to ethanol process–– PretreatmentPretreatment–– HydrolysisHydrolysis–– FermentationFermentation
Pros and cons of bioethanolPros and cons of bioethanolComparison to other Comparison to other biofuelsbiofuels
Biomass compositionBiomass composition
CelluloseCellulose
HemicelluloseHemicellulose
LigninLignin
LigninLigninA major A major barrier to barrier to accessing the accessing the cellulosecelluloseProvides Provides strength and strength and rigidityrigidity
OverviewOverview
What is bioconversion?What is bioconversion?Why bioconversion?Why bioconversion?Biomass compositionBiomass compositionBioconversion to ethanol processBioconversion to ethanol process–– PretreatmentPretreatment–– HydrolysisHydrolysis–– FermentationFermentation
Pros and cons of bioethanolPros and cons of bioethanolComparison to other Comparison to other biofuelsbiofuels
Bioconversion of biomass to Bioconversion of biomass to ethanol (pretreatment)ethanol (pretreatment)
Biomass
Pretreatment
Liquid phase
Solid phaseCellulose
Sugars EthanolFermentation
EthanolSugarsFermentation
Hydrolysis
LigninRecovery
PretreatmentPretreatment
Helps in separation of main biomass Helps in separation of main biomass components (cellulose, hemicellulose and components (cellulose, hemicellulose and lignin)lignin)Increase available surface areaIncrease available surface areaReduce particle size Reduce particle size Ideally pretreatment:Ideally pretreatment:–– SolubilizesSolubilizes hemicellulosehemicellulose–– Increases enzymatic Increases enzymatic hydrolysibilityhydrolysibility of of
cellulosecellulose
Pretreatment Pretreatment ––”disruption””disruption”
Possible methods:Possible methods:–– Mechanical (milling)Mechanical (milling)–– Chemical (acid and base)Chemical (acid and base)–– Biological Biological –– Combination Combination
Steam explosionSteam explosion
Treatment of biomass with highTreatment of biomass with high--pressure pressure steam for a short period of time followed by steam for a short period of time followed by sudden decompressionsudden decompressionAcid (HAcid (H22SOSO44, SO, SO22) impregnation of biomass ) impregnation of biomass increases SE efficiencyincreases SE efficiencyTypical conditions:Typical conditions:–– Temperature: 170Temperature: 170--250250ooC, 338C, 338--482 F482 F–– Time: 10secTime: 10sec--10min10min
Steam gunSteam gun
KarinFill valve
Steam valve
Blow valve
Receiving vessel
Receiving vessel
Pretreated corn stover
OverviewOverview
What is bioconversion?What is bioconversion?Why bioconversion?Why bioconversion?Biomass compositionBiomass compositionBioconversion to ethanol processBioconversion to ethanol process–– PretreatmentPretreatment–– HydrolysisHydrolysis–– FermentationFermentation
Pros and cons of bioethanolPros and cons of bioethanolComparison to other Comparison to other biofuelsbiofuels
Bioconversion of biomass to Bioconversion of biomass to ethanol (hydrolysis)ethanol (hydrolysis)
Biomass
Pretreatment
Liquid phase
Solid phaseCellulose
Sugars EthanolFermentation
EthanolSugarsFermentation
Hydrolysis
LigninRecovery
CelluloseCellulose
The goal of the hydrolysis step is to break the cellulose into simple sugars prior to
fermentation
Must be able to break cellulose to Must be able to break cellulose to get the energyget the energy
Cows, deer, sheepCows, deer, sheepRumen is a Rumen is a fermentation vatfermentation vatMicrobes break Microbes break down the cellulose down the cellulose using the enzyme, using the enzyme, cellulasecellulase
Fungi can break down cellulose tooFungi can break down cellulose too
CellulasesCellulases are are enzymes that enzymes that break down break down cellulosecelluloseWhite rot fungi: White rot fungi: good source of good source of enzymesenzymes
What are What are cellulasescellulases??
Enzymes made by many strains of bacteria Enzymes made by many strains of bacteria and fungiand fungiCatalyzes the Catalyzes the depolymerizationdepolymerization of cellulose of cellulose chainschains–– (details in Renata Bura(details in Renata Bura’’s class)s class)
OverviewOverview
What is bioconversion?What is bioconversion?Why bioconversion?Why bioconversion?Biomass compositionBiomass compositionBioconversion to ethanol processBioconversion to ethanol process–– PretreatmentPretreatment–– HydrolysisHydrolysis–– FermentationFermentation
Pros and cons of bioethanolPros and cons of bioethanolComparison to other Comparison to other biofuelsbiofuels
Bioconversion of biomass to Bioconversion of biomass to ethanolethanol (fermentation)(fermentation)
Biomass
Pretreatment
Liquid phase
Solid phaseCellulose
Sugars EthanolFermentation
EthanolSugarsFermentation
Hydrolysis
LigninRecovery
FermentationFermentation
Defined as:Defined as:Cellular metabolism under anaerobic conditions Cellular metabolism under anaerobic conditions (absence of oxygen) for the production of energy (absence of oxygen) for the production of energy and metabolic intermediatesand metabolic intermediates
Many organisms can “ferment” Many organisms can “ferment” Not all produce ethanol as an endNot all produce ethanol as an end--productproduct
Strain selectionStrain selectionTraditionally been a YeastTraditionally been a YeastYeast:Yeast:–– Single cell microorganismSingle cell microorganism–– FungiFungi–– Facultative anaerobeFacultative anaerobe
Most common industrial Most common industrial fermenterfermenter is is Saccharomyces cerevisiae Saccharomyces cerevisiae (baker’s or brewer’s (baker’s or brewer’s yeast)yeast)Why?Why?
Why Why S. cerevisiaeS. cerevisiae??
Has been selected over thousands of yearsHas been selected over thousands of yearsHigh ethanol yield and productivityHigh ethanol yield and productivityRelatively simple to cultureRelatively simple to culture
FermentationFermentation
(Glycolysis first)
FERMENTATIONFERMENTATION
GLYCOLYSIS
Glucose PyruvateGlucose
FERMENTATION
Cellular respiration
If electron acceptor(such as oxygen)
is present
If electron acceptor(such as oxygen)is NOT present
KREBS CYCLE ELECTRON TRANSPORT ANDOXIDATIVE PHOSPHORYLATION
PYRUVATEPROCESSING
Fermentation Regenerates NADFermentation Regenerates NAD++
Fermentation pathways allow cells to regenerate NAD+
for glycolysis.
Fermentationby-product
Intermediate acceptselectrons from NADH
GENERAL PATHWAY
Alcohol fermentation occurs in yeast.
2 Pyruvate
2 Acetylaldehyde2 Ethanol
FermentationFermentation
Conversion factor 0.51
1g/L of glucose: 0.51g/L ethanol (maximum)
OverviewOverview
What is bioconversion?What is bioconversion?Why bioconversion?Why bioconversion?Biomass compositionBiomass compositionBioconversion to ethanol processBioconversion to ethanol process–– PretreatmentPretreatment–– HydrolysisHydrolysis–– FermentationFermentation
Pros and cons of bioethanolPros and cons of bioethanolComparison to other Comparison to other biofuelsbiofuels
Challenges (Cons)Challenges (Cons)
Feedstock diversityFeedstock diversityEconomical feasibility of the processEconomical feasibility of the process–– Cost of biomassCost of biomass–– Cost of enzymesCost of enzymes–– Ethanol as a final product = very cheapEthanol as a final product = very cheap
EnergyEnergy–– An alternative source of energy for the An alternative source of energy for the
transportation sector produced locallytransportation sector produced locally
Air pollutionAir pollution–– Reduction in greenhouse gas emissionReduction in greenhouse gas emission
Waste eliminationWaste elimination–– Elimination of problems with field Elimination of problems with field
burning/incineration, stockpiling, etc.burning/incineration, stockpiling, etc.
Socio/economical benefitsSocio/economical benefits–– Creation of new jobs, rural developmentCreation of new jobs, rural development
Pros (again)Pros (again)
Sugar cane & sugar cane Sugar cane & sugar cane bagassebagasse
Sugar cane
bagasse
Processing
Ethanol
Corn plantCorn plant
BiofuelsBiofuels--comparisonscomparisons
2.52.5
22--3636
8.08.0
1.31.3
Energy Energy balancebalance
6868NANA0.50 0.50 BiodieselBiodiesel
9191NANANANALignocellulosic ethanolLignocellulosic ethanol
5555--90900.870.873.963.96Cane ethanolCane ethanol
22221.091.094.86 4.86 Corn Corn grain ethanolgrain ethanol
GHEGHEreduction reduction
(%)(%)
Production Production cost ($)cost ($)
Production Production (billion (billion gallons)gallons)
Part 2. MethanolPart 2. Methanol
Toshiba
Casio
Gasifier
Biomass to Liquid Fuel Crude Syngas
(Syngas = CO2 + CO + H2)
Clean Syngas
Scrubber
Bio-Methanol
Methanol Reactor
Wood Biomass
(Wood Alcohol)
Gasifier
How is How is biomethanolbiomethanol made?made?
All the woody biomass is usedAll the woody biomass is usedNOT FROM FERMENTATIONNOT FROM FERMENTATIONWood chips Wood chips gasifiergasifier at high tempat high tempscrubbers scrubbers biomethanolbiomethanolWood to bioethanol yields 99Wood to bioethanol yields 99--142 gal142 galWood to Wood to biomethanolbiomethanol yields 165yields 165--186 186 gal BECAUSE IT USES ALL THE gal BECAUSE IT USES ALL THE BIOMASS, NOT JUST THE SUGARBIOMASS, NOT JUST THE SUGAR
2. 2. Principle of methanol synthesis Principle of methanol synthesis by the gasification methodby the gasification method
Slide adapted from H. Nakagawa
Carbon Hydrates:
(CH2O)n + Oxygen+ water
1000 C
Mixture of Gases:
Hydrogen, carbon monoxide, carbon
dioxide, water Pressure
40-80 atm
Biomethanol
CO + 2H2
CH3OH
TypicalTypical test questionstest questions
How is bioethanol and How is bioethanol and biomethanolbiomethanoldifferent in terms of how they are different in terms of how they are made?made?How is biodiesel different from both How is biodiesel different from both bioethanol and bioethanol and biomethanolbiomethanol in terms in terms of the plant material used? of the plant material used?
Some conversion efficiencies to alcohols
MaterialMaterial EthanolEthanol(gallons / 1 Mg biomass)(gallons / 1 Mg biomass)
MethanolMethanol(gallons/ 1 Mg biomass)(gallons/ 1 Mg biomass)
Sugar caneSugar canewww.itdg.org/docs/technical_information_service/suwww.itdg.org/docs/technical_information_service/sugar_production_from_cane.pdfgar_production_from_cane.pdf, K Vogt estimate, K Vogt estimate
24 24 –– 36 gallons36 gallons(6 (6 -- 9%)9%)
Corner stoverCorner stoverKheshgiKheshgi et al. 2000, et al. 2000, www.ctic.purdue.edu/Core4/StoverNCNU.pdfwww.ctic.purdue.edu/Core4/StoverNCNU.pdf
79 79 –– 119 119 gallonsgallons
WoodWoodwww.cfr.washington.edu/research.Forest_Energywww.cfr.washington.edu/research.Forest_Energy//, , KheshgiKheshgi et al. 2000, K Vogt estimateet al. 2000, K Vogt estimate
99 99 –– 142 142 gallonsgallons
165 165 –– 186 186 gallonsgallons
Chemistry determines how much liquid by-
product produced
Starch or Cellulose being converted
Cellulose and lignin being converted
NOTE: Ethanol cannot be made from lignin, a major component of waste biomass
Then why the focus on bioethanol Then why the focus on bioethanol instead of instead of biomethanolbiomethanol??
Plants contain a lot of nitrogen (not Plants contain a lot of nitrogen (not just “carbon hydrates”)just “carbon hydrates”)Gasification of nitrogen in the Gasification of nitrogen in the presence of oxygen makes toxic NO presence of oxygen makes toxic NO gases gases Toxic byproductsToxic byproductsLower energyLower energySmaller market (but maybe changing)Smaller market (but maybe changing)
SFR SFR biofuelsbiofuels research agenda research agenda
Vision: Cost effective cellulosic transportation fuelsVision: Cost effective cellulosic transportation fuels
•Use mixed biomass sources•With good process yields
•Profitable at moderate economies of scale
•Co-produce fuels and high value products
•Commodity Chemicals•Polymers•Pulp Fibers
ReviewReview
Ethanol from fermentation of starch from Ethanol from fermentation of starch from grain or sucrose from sugarcanegrain or sucrose from sugarcaneBioethanol from fermentation of Bioethanol from fermentation of any any cellulosiccellulosic biomassbiomass-- can be produced can be produced sustainably; sustainably; can be mixed with gasolinecan be mixed with gasolineBiodiesel from plant oilsBiodiesel from plant oils-- high energy high energy fuel;fuel;notnot compatible with most US compatible with most US cars (yescars (yes--bus)bus)BiomethanolBiomethanol-- lower energy; smaller market; lower energy; smaller market; but efficient production; can be used in but efficient production; can be used in power cellspower cells
Study GuideStudy GuideBiofuel vs PetroleumBiofuel vs Petroleum--based fuelbased fuelExam questions will relate the lectures Exam questions will relate the lectures to each otherto each other–– Advantages and disadvantages of the Advantages and disadvantages of the
different fuels (methanol, ethanol, different fuels (methanol, ethanol, bioethanol, and biodiesel) and compared bioethanol, and biodiesel) and compared to petroleumto petroleum
–– How are they similar and different from How are they similar and different from each other? Make a table to compareeach other? Make a table to compare
EXAM # 2 IS ON TUESDAY NOVEMBER 30TH: Endophyte-Assisted Phytoremediation plus the three bioenergy lectures so far
Comparing FuelsComparing FuelsStructureStructure–– Diesel: saturated hydrocarbons, C10Diesel: saturated hydrocarbons, C10--C15C15–– Biodiesel:Biodiesel:–– Ethanol/Bioethanol:Ethanol/Bioethanol:–– Methanol:Methanol:
Energy contentEnergy content–– Diesel: High energy contentDiesel: High energy content–– Biodiesel:Biodiesel:–– Ethanol/Bioethanol:Ethanol/Bioethanol:–– MethanolMethanol
Air pollutionAir pollution–– Diesel: HighDiesel: High–– Biodiesel:Biodiesel:–– Ethanol/Bioethanol:Ethanol/Bioethanol:–– Methanol:Methanol:
Fuel Comparisons (cont.)Fuel Comparisons (cont.)
What is it? What is it? Sources? Sources? Microbes needed? Microbes needed? How is each different from petroleum How is each different from petroleum or diesel? or diesel? Benefits of the biofuel?Benefits of the biofuel?
References References
www.ento.vt.edu/~salom/SPBbiology/blustain.htmlwww.ento.vt.edu/~salom/SPBbiology/blustain.htmlwww.pherotech.com/new_products.htmlwww.pherotech.com/new_products.htmlwww.dnr.wa.gov/../issues/2002issues.htmlwww.dnr.wa.gov/../issues/2002issues.htmlwww.laco.ufpe.br/prh28/www.laco.ufpe.br/prh28/www.biowww.bio--pro.de/en/region.rhein/magazin/01440pro.de/en/region.rhein/magazin/01440www.maize.agron.iastate.edu/corngrows.htmlwww.maize.agron.iastate.edu/corngrows.htmlwww.nrel.govwww.nrel.govwww.energy.iastae.eduwww.energy.iastae.eduwww.usda.gov/wps/portal/usdahomewww.usda.gov/wps/portal/usdahomewww.ethanolwww.ethanol--gec.org/clean/cf13.htmgec.org/clean/cf13.htmwww.eere.energy.govwww.eere.energy.gov/biomass//biomass/