John Jechura – jjechura@mines.eduUpdated: January 4, 2015

Biomass as Energy Resource

Energy Markets Are Interconnected

2

https://publicaffairs.llnl.gov/news/energy/energy.html

Combustion

• Conversion efficiency ‐ 20‐25% to power

• Mineral management

• Emissions NOx, SOx, CO, particulate

• Mature technology

3

Petroleum Production"Fossil fuels are a one‐time gift that lifted us up from subsistence agriculture and eventually should lead us to a future based on renewable resources." 

Hubbert's Peak: The Impending World Oil Shortage

by Kenneth S. Deffeyes 

4

Biomass Pros & ConsPros:

• Domestic benefits

Reduced trade deficit

Create jobs

Strengthen rural economies

Local raw materials

• Renewable resources

• Carbon cycle to reduce build up of greenhouse gases

• Technology improvements should continue to reduce costs

Cons:

• Lower energy density

• Solids difficult to handle

• High water content

• Competing uses as high value food stuff

• Symbiotic relationship — producers & users

• Commercial Issues

Biomass feedstock, availability, & cost

Suitable sites

Production technologies

Qualified owner‐operator

Project financing

5

Clean Air Act & Amendments

• Series of Clean Air Acts

Air Pollution Control Act of 1955

Clean Air Act of 1963

Air Quality Act of 1967

Clean Air Act Extension of 1970

Clean Air Act Amendments in 1977 & 1990

• 1977 Clean Air Act amendments set requirements for "substantially similar gasoline" 

Oxygenates added to make motor fuels burn more cleanly & reduce tailpipe pollution (particularly CO)

Required that oxygenates be approved by the U.S. EPA 

MTBE & ethanol primary choices

• California Phase 3 gasoline regulation approved by California Air Resources Board in December 1999 prohibits gasoline with MTBE after December 31, 2002

Water quality issues

6

2007 Renewable Fuel Standard

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022

Millions Annual

Gallons

Advanced Biofuels

Corn Stach Derived Ethanol (Max)

Energy Independence & Security Act of 2007

Renew-able Fuel Standard

Advanced Biofuels

Cellulosic Biofuel RFS - AB

Year Mgal/yr Mgal/yr Mgal/yr Mgal/yr

2006 4,000 4,000

2007 4,700 4,700

2008 9,000 9,000

2009 11,100 600 10,500

2010 12,950 950 100 12,000

2011 13,950 1,350 250 12,600

2012 15,200 2,000 500 13,200

2013 16,550 2,750 1,000 13,800

2014 18,150 3,750 1,750 14,400

2015 20,500 5,500 3,000 15,000

2016 22,250 7,250 4,250 15,000

2017 24,000 9,000 5,500 15,000

2018 26,000 11,000 7,000 15,000

2019 28,000 13,000 8,500 15,000

2020 30,000 15,000 10,500 15,000

2021 33,000 18,000 13,500 15,000

2022 36,000 21,000 16,000 15,000

7

Administered by the Environmental Protection Agency

http://epa.gov/otaq/renewablefuels/index.htm

EPA Clarifications & Adjustments

• RFS‐2 Advanced Biofuels amounts have had to be adjusted since 2010

Significantly less development of cellulosic biofuels than had been anticipated in 2007

• Adjustments have been required each year

Have needed to drastically reduce Cellulosic Biofuel

Increases allowed biodiesel 

Have started to expand the types of allowable advanced biofuel

Proposed 2014 amounts are lower than Standard – takes into account “blend wall” & actual fuel sales

8

Ref: http://epa.gov/otaq/fuels/renewablefuels/regulations.htm

Cellulosic Biofuels Projects?

9

Last EIA update: February 26, 2013Ref: http://www.eia.gov/todayinenergy/detail.cfm?id=10131

Typical Elemental Analyses:Fossil Fuels, Biomass, & Biofuels

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1st Generation Biofuels

• Ethanol

Typically derived from fermentation of sugars & starches

• US: Corn starch

• Brazil: Sugar cane juice

• Biodiesel

FAME – Fatty Acid Methyl Ester

From fats and oils

• US: Soybean oil

• Europe: Rapeseed oil 

11

Edible Constituents of Biomass

•Starch: 70%–75% (corn)

• Readily available and hydrolysable

• Basis for existing U.S. “biorefineries”

•Oil: 4%–7% (corn), 18%–20% (soybeans)

• Readily separable from biomass feedstock

• Basis for oleochemicals and biodiesel

•Protein: 20%–25% (corn), 80% (soybean meal)

• Key component of food

• Chemical product applications 

12

Ethanol From Corn Starch

• Two primary processing options

Wet mills

• Expensive to build – not common

• Sophisticated operations

• Multiple products

o Fuel, food, & fiber

Dry mills

• Most common – fairly simple operations

o Processing options making more sophisticated

• Limited products – primarily ethanol & DDG/DDGS

o More sophisticated operations may add germ, fermentation co‐products, … 

13

Ethanol from Corn vs. Sugar Cane

14

Liquifact ion

Starch

Power

Saccharif icat ion & Fermentat ion

DiluteEthanol

Dist illat ion, Rect if icat ion, &

Dehydrat ion

Centrifugat ion

Whole St illage

ThinStillage Evaporat ion

Syrup

Evaporat ion

RecyclableWater

Wet DDG

JuiceExtract ion

JuiceFermentat ion Dilute

Ethanol

Dist illat ion, Rect if icat ion, &

Dehydrat ion

Bagasse(Fiber)

PowerDrying

RecyclableWater

DriedBagasse

Worldwide Ethanol Capacity

15

Country 2004 2005 2006 2007 2008

U.S. 3,535 4,264 4,855 6,499 9,000

Brazil 3,989 4,227 4,491 5,019 6,472

China 964 1,004 1,017 486 502

India 462 449 502 53 66

Europe 858 929 1,030 570 734

Thailand 74 79 93 79 90

Canada 61 61 153 211 238

Australia 33 33 39 26 26

Others 794 1,104 1,309 158 208

Total 10,770 12,150 13,489 13,102 17,335

http://www.ethanolrfa.org/industry/statistics/#E 5/28/2009

Source: F.O. Licht

Annual World Ethanol Production by Country(Millions of Gallons, All ethanol Grades)

U.S

.

Braz

il

Chi

na

Indi

a

Euro

pe

Thai

land

Can

ada

Aust

ralia

Oth

ers

2004

2006

20080

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

Million Gallons (All Ethanol Grades)

Current US Ethanol Capacity

16

YearMillions of

Gallons

1980 175

1981 215

1982 350

1983 375

1984 430

1985 610

1986 710

1987 830

1988 845

1989 870

1990 900

1991 950

1992 1,100

1993 1,200

1994 1,350

1995 1,400

1996 1,100

1997 1,300

1998 1,400

1999 1,470

2000 1,630

2001 1,770

2002 2,130

2003 2,800

2004 3,400

2005 3,904

2006 4,855

2007 6,5002008 9,000

http://www.ethanolrfa.org/industry/statistics/#A7/21/2008

Historic U.S. fuel Ethanol Production

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

Millions of Gallons

1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008

Criticisms of Ethanol

• Food vs fuel

Divert land from growing food to growing fuel

• Just a farmer subsidy

• Ethanol not compatible with gasoline infrastructure

RBOB – special blend stock to allow for RVP increase at E10 levels

Picks up water

• Cannot be transported in petroleum pipelines – use water slugs between batches

• Takes more energy to make that you get back

Based on “wells to wheels” Life Cycle Assessment

LCA normally compare energy out vs. fossil energy in

Highly dependent upon feedstock, farming practice, processing, … 

• Takes too much water to make

Highly dependent upon feedstock, farming/irrigation practice, processing, …

17

U.S. Corn Yield & Amount to Ethanol

18

0

20

40

60

80

100

120

140

160

180

1840 1860 1880 1900 1920 1940 1960 1980 2000 2020

Year

U.S

. C

orn

Yie

ld [

bu

/acr

e]

http://ethanol.typepad.com/my_weblog/2011/01/response‐to‐the‐wsj‐ethanol‐is‐not‐reducing‐the‐amount‐of‐corn‐for‐food.html#tp

http://quickstats.nass.usda.gov/results/AFBDFE1E‐1AFC‐35DE‐8A93‐7FB72F0DA089?pivot=short_desc

Corn Ethanol Energy Balance

19

-40,000

-30,000

-20,000

-10,000

0

10,000

20,000

30,000

40,000

1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004

Net

Ene

rgy

Valu

e (B

tu/g

allo

n)

Ho

Marland and Turhollow

Pimentel Pimentel

Keeney and DeLuca

Lorenz and Morris

Shapouri et al.

Shapouri et al.

Wang et al.

Agri. Canada

Kim and Dale

GraboskiWang

Source: M. Wang (2003)

A Response to Five Ethanol Criticisms• Ethanol requires more energy to make than it 

yields? ANL research has shown corn ethanol delivers positive

energy balance of 8.8 MJ/L (32,000 Btu/gal). • Corn production efficiency has increased dramatically –

160 bu/acre today vs. 95 bu/acre in 1980• Ethanol production more energy‐efficient in modern dry 

mills vs. older wet mills• Ethanol yield per bushel also increased about 50% since 

1980

• Ethanol production reduces our food supply? Only 1% of corn grown in U.S. eaten by humans. Rest is No. 2 

yellow field corn, indigestible to humans; used in animal feed, food supplements and ethanol.

Bushel of corn used for ethanol produces 1.5 lbs corn oil, 17.5 lbs high‐protein DDGS, 2.6 lbs corn meal, & 31.5 lbsstarch.• Starch used for sweeteners or produce 2.8 gal ethanol. • DDGS displaces whole corn & some soybeans used in 

animal feed.

• Ethanol crops and production emit more greenhouse gases than gasoline? Blending ethanol with gasoline dramatically reduces CO 

tailpipe emissions & tailpipe emissions of VOCs that form ozone.

LCA of ethanol found “at present and in the near future, using corn ethanol reduces greenhouse gas emission by more than 20%, relative to those of petroleum gasoline.” 

• Ethanol requires too much water to produce? Amount of water used to make ethanol has declined 

dramatically. Requirements today are about 3.5 gallons water/gallon ethanol.• Little more than it takes to process a gallon of gasoline. 

Much of the criticism about ethanol’s water requirements stem from irrigation of feedstock crops in drier climates. However, most ethanol is produced crops grown in the Midwest without irrigation.

• Cars get lower gas mileage with ethanol? True on a mile per gal basis. E85 about 25% lower mpg than 

gasoline. However, depending on cost of ethanol could have a lower 

dollars per mile. Higher octane of ethanol could lead to modified engines 

(compression ratios & valve timings) that are optimized for ethanol use.

20

Blog by Forrest Jehlik, Argonne National Laboratoryhttp://www.wired.com/autopia/2011/06/five‐ethanol‐myths‐busted‐2/

Response to 6 Biofuel “Myths”• 40% of the US corn crop is used to make biofuel

13% of the US corn crop is used to make, specifically, fuel ethanol

Per‐acre crop yields have grown significantly in recent years – taken over the long term, the US has not had to increase its corn acreage to make fuel ethanol. There’s less land used to grow grain in the US today than 100 years ago

• “Now that the United States is using 40 percent of its crop to make biofuel, it is not surprising that tortilla prices have doubled in Guatemala.”

Two types of corn grown ‐‐ #2 yellow corn (animal feed & biorefineries) & white corn (food)

Very little white corn grown in US. Acres dedicated to white corn in the US have not decreased since passage of the RFS.

• The world is going to climate hell and there’s nothing anyone can do about it, except starve. If you don’t die of thirst, first.

Drought resistant strains of crops being developed by multiple companies; Ceres given as example

• Biofuels cause higher carbon emissions, instead of lowering them

According to EPA, corn ethanol reduces greenhouse gas emissions by 20% compared to the use of fossil fuels, including contributions for direct & indirect  land‐use change

• Biofuels have lower fuel economy

Ethanol has 70% energy density compared to gasoline but higher octane rating.

Cost per mile driven is the important factor

• Biofuels use more energy in their production than they provide as a transport fuel.

Depending on study, energy return for corn ethanol is 1.3 to 1, sugarcane ethanol (primarily from Brazil) is 8:1, biodiesel is 2.5:1, & cellulosic biofuels range from 2:1 to 36:1

Dependent on process improvements, …

21

Blog by Jim Lane, Biofuels Digesthttp://www.biofuelsdigest.com/bdigest/2013/01/09/the‐biggest‐biofuels‐myths‐demythtefied/

Conversion of FOG (Fats, Oils & Greases)

• Biodiesel

• Hydrogenation

22

Nat GasCatalyt ic

Reforming & Synthesis

MethanolWater

Oxygen

Mild Condit ionsLiquid Phase

Base Catalyzed

Fats, Oils, & Grease

FAME(Biodiesel)

Glycerin

Biodiesel – Fats & Oils

23

Picture of molecule from:“Hydrotreating in the production of green diesel”R. Egeberg, N. Michaelsen, L. Skyum, & P. ZeuthenJournal of Petroleum Technology, 2nd Quarter 2010 

Biodiesel Production

24

Ref: http://www.endress.com/eh/home.nsf/#page/~biodiesel‐process

Biodiesel Production Example

25

Soybean oil cost (March 2014 contract) = $837.54 per tonne = $0.3799 per lb = $2.917 per gal @ 0.92 kg/L Methanol cost (December 2013) = $632 per tonne = $0.2867 per lb = $1.900 per gal @ 332.6 gal/tonne

Oil Methanol Glycerin FAMEFormula C3H5‐(OOC‐C17H33)3 CH3OH C3H5(OH)3 CH3‐OOC‐C17H33

Molar Mass 885.4 32.0 92.1 296.5wt% C 77% 37% 39% 77%wt% H 12% 13% 9% 12%wt% O 11% 50% 52% 11%Density (g/cm3) 0.92 0.80 1.26 0.90Stoichiometric Coefficient 1 3 1 3Mass 885.4 96.1 92.1 889.5Volume 962.4 120.2 73.1 988.3Mass Ratio 1.00 0.11 0.10 1.00Volume Ratio 1.00 0.12 0.08 1.03

Oleic Fatty Acid (18:1)

“Hydrotreating in the production of green diesel”R. Egeberg, N. Michaelsen, L. Skyum, & P. ZeuthenJournal of Petroleum Technology, 2nd Quarter 2010 

2nd Generation & Advanced Biofuels

• Cellulosic/Lignocellulosic Ethanol Biochemical pathway

• Utilize sugars from cellulose & hemicellulose

Thermochemical pathway• Utilize all carbon, including lignin

• Butanol More closely compatible to petroleum derived gasoline

From fermentation (BP/DuPont) Gasification & catalytic synthesis

• Green/Renewable Diesel/Gasoline

Hydrocarbon just like petroleum‐derived products

Multiple sources & processing paths

• Hydroprocessed fats & oils

o Both diesel & gasoline

o Could be integrated into existing refineries

• End product from gasification & FT synthesis

o Excellent diesel

o Poor gasoline – requires isomerization

26

US Biomass Resource Base

27

Perlack, R.D.; Wright, L.L.; Turhollow, A.F.; Graham, R.L.; Stokes, B.J.; Erbach, D.C. Biomass as Feedstock for a Bioenergy and Bioproducts Industry: the Technical Feasibility of a Billion‐Ton Annual Supply. A joint U.S. Department of Energy and U.S. Department of Agriculture report. DOE/GO‐

102995‐2135 & ORNL/TM‐2005/66. April 2005. 

High Yield Increase

0 50 100 150 200 250 300 350 400

Other residues

Other crop residues

CRP Biomass

Soybean residues

Small grain residues

Wheat Straw

Corn Stover

Perennial (Energy) Crops

Manures

Grains to biofuels

Soybeans

Logging Residue

Other Removal Residue

Fuel Treatments (Timberland)

Fuel Treatments (Other Forestland)

Fuel Wood

Wood Residues

Pulping Liquors

Urban Wood Residue

Million Tons Annually

US Biomass Resource Base

28

0 100 200 300 400 500

Existing &UnexploitedResources

High Yield GrowthWithout Energy

Crops

High Yield GrowthWith Energy Crops

Million Tons Annually

Forest Resources Total

Grains & Manure Sub-Total

Ag Residues (non Energy Crops)

Perennial (Energy) Crops

Perlack, R.D.; Wright, L.L.; Turhollow, A.F.; Graham, R.L.; Stokes, B.J.; Erbach, D.C. Biomass as Feedstock for a Bioenergy and Bioproducts Industry: the Technical Feasibility of a Billion‐Ton Annual Supply. A joint U.S. Department of Energy and U.S. Department of Agriculture report. DOE/GO‐

102995‐2135 & ORNL/TM‐2005/66. April 2005. 

Significance of the 1.3 Billion Ton Biomass Scenario

29

NREL analysis, July 2005, documented in:J.L. Jechura, Ethanol Potential from Billion Ton Biomass Resource, NREL Technical Memo, May 22, 2006.

Non‐Edible Constituents of Biomass

30

• Lignin: 15%–25%

• Complex aromatic structure

• Very high energy content

• Resists biochemical conversion

• Hemicellulose: 23%–32%

• Xylose is the second most abundant sugar in the biosphere

• Polymer of 5‐ and 6‐carbon sugars, marginal biochemical feed

• Cellulose: 38%–50%

• Most abundant form of carbon in biosphere

• Polymer of glucose, good biochemical feedstock

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

OHO

HO

H3CO

OH

OCH3

OCH3

O

O

O

OH

OCH3

OCH3

H3CO

OO

HO

H3CO

HO

OCH3

OCH3

OHO

HO

H3CO

OH

OCH3

OCH3O

O

OH

OCH3

OCH3

OCH3

OO

O

OH

HO

O

OO

O

OH

HO

OH

OH

OO

O

OH

HO

OH

OH

OO

O

OH

HO

OH

OH

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

O

OO

OH

OH

OH

HOHO

OHO

Biofuels Technology “Square Dance”

Liquid Phase Gas Phase

Fermentation

Amyris LanzaTech

Solazyme Coskata

Gevo INEOS Bio

Traditional Ethanol

Catalytic Conversion

Virent KiOR

Traditional Biodiesel Enerkem

Envergent

Anellotech

Dynamotive

ClearFuels/Rentech

SilvaGas/Rentech

CombinationsZeaChem: Hydrolysis, Fermentation, & Catalytic Conversion

Saphire Energy: Algae lipids to biodiesel & residual biomass to power

31

http://biofuelsdigest.com/bdigest/2011/04/18/the‐biofuels‐technology‐square‐dance/

Biochemical Conversion Process

32

Feedstock Handling

CO2Ethanol

LigninResidue

Enzyme

Corn Stover

Steam

Electricity

Steam & Acid Liquor

Pretreatment S/L Separation

ConditioningSaccharification&

FermentationDistillation &Ethanol Purification

WastewaterTreatment

Burner/BoilerTurbogenerator

Lime

Steam

Gypsum

Dewatering

Recycle

Lignocellulosic Biomass to Ethanol Process Design and Economics NREL/TP‐510‐32438  June, 2002 http://www.nrel.gov/docs/fy02osti/32438.pdf

Thermochemical Conversions

• Pyrolysis Thermal conversion (destruction) of organics in the absence of oxygen 

In the biomass community, this commonly refers to lower temperature thermal processes producing liquids as the primary product

Possibility of chemical and food byproducts• Gasification Thermal conversion of organic materials at elevated temperature and reducing conditions to produce primarily permanent gases, with char, water, & condensibles as minor products

Primary categories are partial oxidation and indirect heating

33

Syngas Products

• Hydrogen

• Methanol and its derivatives (NH3, DME, MTBE formaldehyde, acetic acid, MTG, MOGD, TIGAS)

• Fischer Tropsch Liquids

• Ethanol

• Mixed alcohols

• Olefins

• Oxosynthesis

• Isosynthesis

34

SyngasCO + H2

Methanol

H2OWGSPurify

H2N2 over Fe/FeO

(K2O, Al2O3, CaO)NH3

Cu/ZnOIsosynthesis

ThO2 or ZrO2

i-C4

Alkali-doped

ZnO/Cr2 O3

Cu/ZnO; Cu/ZnO/Al2 O3

CuO/CoO/Al2 O3

MoS2

MixedAlcohols

Oxosynthesis

HCo(CO)4

HCo(CO)3 P(Bu3 )

Rh(CO)(PPh3 )3

AldehydesAlcohols

Fischer-Tropsch

Fe, C

o, R

u

WaxesDiesel

OlefinsGasoline

Ethanol

Co, Rh

FormaldehydeAg

DME

Al 2O

3

zeolites

MTOMTG

OlefinsGasoline

MTBEAcetic Acid

carb

onyla

tion

CH3O

H +

COCo

, Rh,

Ni

M100M85DMFC

Direct Use

hom

olog

atio

nC

o

isob

utyl

ene

acid

ic io

n ex

chan

ge

Alcohol Synthesis

Biomass

Flue Gas

Dryer

Scrubber

Sludge(Waste)

CO2

Sulfur

Acid Gas Cleanup

Air

Gasifier

Solids(Waste)

Steam

Alcohol Separation

Methanol & Water

Ethanol

MixedAlcohols

Steam

Reformer

Air

Compressor

Water to recycle

Compressor

Thermochemical Conversion

35

Personal communication Ryan Davis, National Renewable Energy Laboratory. November 2009. 

Hydrodeoxygenation of Organic Oils

• Organic oils can be hydrotreated to form “green” diesel

Fully compatible with petroleum derived diesel

Excellent cetane number because of the straight chain nature

• Challenges for catalyst design

Oxygen relatively easy to remove, but large oxygen content

Prefer to deoxygenate to CO2 to maximize fuel usage of H2

36

“Hydrotreating in the production of green diesel”R. Egeberg, N. Michaelsen, L. Skyum, & P. ZeuthenJournal of Petroleum Technology, 2nd Quarter 2010 

Green Diesel Production Examples

37

Oil Hydrogen Water Propane OctadecaneFormula C3H5‐(OOC‐C17H33)3 H2 H2O C3H8 C18H38

Molar Mass 885.4 2.0 18.0 44.1 254.5%C 77% 0% 0% 82% 85%%H 12% 100% 11% 18% 15%%O 11% 0% 89% 0% 0%Density (g/cm3) 0.92 1.00 0.51 0.78Stoichiometric Coefficient 1 15 6 1 3Mass 885.4 30.2 108.1 44.1 763.5Volume (Liquid) 962.4 108.1 86.5 978.8Mass Ratio 1.00 0.03 0.12 0.05 0.86Volume Ratio 1.00 0.11 0.09 1.02scf/bbl 2,071

Oil Hydrogen Carbon Dioxide Propane HeptadecaneFormula C3H5‐(OOC‐C17H33)3 H2 CO2 C3H8 C17H36

Molar Mass 885.4 2.0 44.0 44.1 240.5%C 0% 0% 0% 0% 0%%H 0% 0% 0% 0% 0%%O 0% 0% 0% 0% 0%Density (g/cm3) 0.92 0.51 0.78Stoichiometric Coefficient 1 6 3 1 3Mass 885.4 12.1 132.0 44.1 721.4Volume (Liquid) 962.4 86.5 924.9Mass Ratio 1.00 0.01 0.15 0.05 0.81Volume Ratio 1.00 0.09 0.96scf/bbl 828

Oleic Fatty Acid (18:1)

Oleic Fatty Acid (18:1)

Expectations for Hydrotreating Fats & Oils

• Configuration

Expect to have similar configuration & materials of construction as hydrodesulfurization

Different catalyst than hydrodesulfurization

Lower severity expected?

• Oxygen easier to remove

• Fewer complex molecular structures

• But experience shows higher reactor temperatures

Additional processing of feed?

• Hydrogen requirements

5X or more than hydrodesulfurization

• Product considerations

Remove the produced CO2/CO/H2O 

Fractionation required to remove light ends

• Will get additional light ends from autothermal cracking

• Propane & other light gases to LPG

• Naphtha should go to Isomerization

Distillate 

• Extremely high cetane number

• May have cloud point issues

• High portion of the boiling point fraction 

38

Other conversions analogous to petroleum refining• KiOR process uses a fluidized bed catalytic cracking unit to convert biomass into petroleum‐like gasoline, diesel, & residual fuel oil

Demonstration plant in Columbus, MS

• 500 bone dry ton/day wood chips

• 15 bpd liquid products – 13 MMgal/yr

Next commercial facility to be in Natchez, MS –1,500 bone dry ton/day feedstock

39

http://www.kior.comImage: http://www.kior.com/content/?s=11&t=Technology

Algae 

• Better solar collector than land‐based biomass- Higher solar utilization

• Lower land use requirements

- Can use brackish water- Limitation is getting carbon to the organism• Co‐locate with power plants – use CO2 in flue gas

• Biofuels potential- Kill the algae & harvest its natural oils• Biodiesel or biocrude feedstock

- Biocatalyst to secrete desired product• Like yeast for fermentation• Hydrogen production possible

• Near‐term processing steps

Cultivation

• Open ponds

o Low cost but high potential for contamination

• Photo bioreactors – flat panel, tubular, column

o Higher cost but more controlled conditions

Harvesting

• High water content of algae

Oil extraction

• Intercellular rather than intracellular

o Usually chemical extraction

40

General Cultivation & Processing of Algae

41

“Algal Feedstock‐Based Biofuels: Separating Myth from Reality”A. Darzins, NREL Power Lunch Lecture Series

February 18, 2009 

Algal Oil Extraction

42

“Algal Feedstock‐Based Biofuels: Separating Myth from Reality”A. Darzins, NREL Power Lunch Lecture Series

February 18, 2009 

Desirable Features of Growing Algal Oil

43

“Algal Feedstock‐Based Biofuels: Separating Myth from Reality”A. Darzins, NREL Power Lunch Lecture Series

February 18, 2009 

Potential Oil Yields

44

“Algal Feedstock‐Based Biofuels: Separating Myth from Reality”A. Darzins, NREL Power Lunch Lecture Series

February 18, 2009 

Resource Requirements

45

“Algal Feedstock‐Based Biofuels: Separating Myth from Reality”A. Darzins, NREL Power Lunch Lecture Series

February 18, 2009 

Illustration by Oak Ridge National Lab 46