Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.
-
date post
21-Dec-2015 -
Category
Documents
-
view
214 -
download
0
Transcript of Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.
![Page 1: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/1.jpg)
Bioconversion of biomass to ethanol-an overview
Renata Bura
November 25th, 2008
![Page 2: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/2.jpg)
Overview
• What is bioconversion?• Why bioconversion?• Sugar cane to ethanol• Corn to ethanol• Biomass composition• Bioconversion to ethanol process
– Pretreatment– Hydrolysis– Fermentation
• Pros and cons of bioethanol
![Page 3: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/3.jpg)
What is bioconversion?
• General: a process which uses biological agents (microorganisms or protein) to transform a feedstock into desirable products.
Bioethanol• A chemical/biochemical process by
which lignocellulosic materials are converted to ethanol and other co-products.
![Page 4: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/4.jpg)
Bioconversion
Biomass
Pretreatment
Hydrolysis
Fermentation Distillation
Ethanol
![Page 5: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/5.jpg)
Why bioethanol?
![Page 6: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/6.jpg)
Ethanol (CH3CH2OH)
• Ethyl alcohol, grain alcohol– Clear, colorless liquid
• Ethanol made from cellulosic biomass instead of starch crops-bioethanol
• Advantages of bioethanol– Domestic renewable fuel sources– Reduces reliance on foreign oil– Cleaner fuel sources– Easily produced and stored– Increases fuel octane number for little cost
![Page 7: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/7.jpg)
Energy content
Gasoline Ethanol Biodiesel
100% 67% 86%
![Page 8: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/8.jpg)
World ethanol production
![Page 9: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/9.jpg)
Sugar cane, sugar cane bagasse
Sugar cane
bagasse
Processing
Ethanol
![Page 10: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/10.jpg)
Sugar cane bioethanol
• Brazil produces 3,96 billion gallons of ethanol from sugar cane
• Production cost $0.87/gallon, the lowest in the world
• Fossil fuel energy used to make the fuel (input) compared with energy in the fuel (output) 1:8
• Green house emission during production and use 56% less compared with gasoline
![Page 11: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/11.jpg)
Corn plantCorn kernel (without the fibre)-starch alcoholCorn fibre-lignocellulosic alcoholCorn stover-lignocellulosic alcohol
![Page 12: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/12.jpg)
![Page 13: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/13.jpg)
Corn to ethanol
• US produces 4,86 billion gallons of ethanol from corn (2006)
• Production cost ~$1.09/gallon • Fossil fuel energy used to make the fuel
(input) compared with energy in the fuel (output) 1:1.3 or negatives values
• Greenhouse gas emission during production and use 22% less compared with gasoline
![Page 14: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/14.jpg)
“We can get fuel from apples, weeds, sawdust, almost anything…..And it remains for someone to find how this fuel can be produced commercially-better fuel at a better price than we now know.”
Henry Ford
Henry Ford
![Page 15: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/15.jpg)
Why bioconversion?
• Energy– An alternative source of energy for the
transportation sector produced locally• Air pollution
– Reduction in greenhouse gas emission• Waste elimination
– Elimination of problems with field burning/incineration, stockpiling, etc.
• Socio/economical benefits– Creation of new jobs, rural
development
![Page 16: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/16.jpg)
Possible lignocellulosic feedstocks
• Agricultural residues (corn stover, corn fibre, wheat straw, rice straw)
• Wood residues• Paper waste• Municipal solids waste
![Page 17: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/17.jpg)
Biomass composition
![Page 18: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/18.jpg)
Cellulose
![Page 19: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/19.jpg)
Hemicellulose
![Page 20: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/20.jpg)
Lignin
![Page 21: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/21.jpg)
Bioconversion of biomass to ethanol (pretreatment)
Biomass
Pretreatment
Liquid phase
Solid phase
Cellulose
Sugars EthanolFermentation
Ethanol SugarsFermentation
Hydrolysis
LigninRecovery
![Page 22: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/22.jpg)
Pretreatment-”disruption”
• Helps in separation of main biomass components (cellulose, hemicellulose and lignin)
• Increase available surface area• Reduce particle size
![Page 23: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/23.jpg)
Steam explosion
• Treatment of biomass with high-pressure steam for a short period of time followed by sudden decompression
• Acid (H2SO4, SO2) impregnation of biomass increases SE efficiency
• Typical conditions:– Temperature: 170-250oC, 338-482 F– Time: 10sec-10min
![Page 24: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/24.jpg)
Steam gun
KarinFill valve
Steam valve
Blow valve
Receiving vessel
Receiving vessel
Pretreated corn stover
![Page 25: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/25.jpg)
Bioconversion of biomass to ethanol (hydrolysis)
Biomass
Pretreatment
Liquid phase
Solid phase
Cellulose
Sugars EthanolFermentation
Ethanol SugarsFermentation
Hydrolysis
LigninRecovery
![Page 26: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/26.jpg)
What are cellulases?
• Produced by many strains of bacteria and fungi
• Catalyzes the depolymerization of cellulose chains– Endoglucanases– Exoglucanases– β-glucosidases
![Page 27: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/27.jpg)
Cellulases
Endoglucanases (EG) cutting the cellulose chains randomly
Cellobiohydrolyses (CBH) cutting cellobiose units of the ends of the cellulose chains
Binding domain Catalytic domain
![Page 28: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/28.jpg)
Bioconversion of biomass to ethanol (fermentation)
Biomass
Pretreatment
Liquid phase
Solid phase
Cellulose
Sugars EthanolFermentation
Ethanol SugarsFermentation
Hydrolysis
Lignin Recovery
![Page 29: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/29.jpg)
Fermentation
• Defined as: Cellular metabolism under anaerobic conditions
(absence of oxygen) for the production of energy and metabolic intermediates
• Many organisms can “ferment” (i.e., grow anaerobically)
• Not all produce ethanol as an end-product of fermentation
![Page 30: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/30.jpg)
Strain selection
• Choice of microorganism for ethanol production has traditionally been a Yeast
• Yeast:– Single cell microorganism– Fungi– Facultative anaerobe
• Most common industrial fermenter is Saccharomyces cerevisiae (baker’s or brewer’s yeast)
• Why?
![Page 31: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/31.jpg)
Fermentation
Conversion factor 0.51
1g/L of glucose: 0.51g/L ethanol (maximum)
![Page 32: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/32.jpg)
Biofuels-comparison
Production (billion gallons)
Production cost ($)
Energy balance
GHEreductio
n (%)
Corn 4.86 1.09 1.3 22
Cane 3.96 0.87 8.0 55-90
Lignocellulose
NA NA 2-36 91
Biodiesel 0.50 NA 2.5 68
![Page 33: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/33.jpg)
Alternative options??…….
![Page 34: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/34.jpg)
Flexible-Fuel Vehicles (FFV)
• Use E85 (85% ethanol and 15% gasoline)• Cost of FFV is similar to traditional gasoline
vehicle• 1gallon of E85 provides the same energy as
0.72 gallons of gasoline (lower E content)• Special materials required for fuel lines,
hoses, valves, gaskets, fuel tank (corrosive ethanol)
• Washington state more than 35, 000 of FFVs (U.S. over 4 million FFVs)– Ford Focus, Chrysler Sebring, Dodge Stratus,
Dodge Caravan, Chevrolet Avalanche
![Page 35: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/35.jpg)
Summary• What is bioconversion?• Why bioconversion?• Sugar cane to ethanol• Corn to ethanol• Biomass composition• Bioconversion to ethanol process
– Pretreatment– Hydrolysis– Fermentation
• Pros and cons• FFV
![Page 36: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/36.jpg)
![Page 37: Bioconversion of biomass to ethanol-an overview Renata Bura November 25 th, 2008.](https://reader037.fdocuments.in/reader037/viewer/2022110322/56649d5f5503460f94a3f501/html5/thumbnails/37.jpg)
References
• www.ento.vt.edu/~salom/SPBbiology/blustain.html
• www.pherotech.com/new_products.html• www.dnr.wa.gov/../issues/2002issues.html• www.laco.ufpe.br/prh28/• www.bio-pro.de/en/region.rhein/magazin/01440• www.maize.agron.iastate.edu/corngrows.html• www.nrel.gov• www.energy.iastae.edu• www.usda.gov/wps/portal/usdahome• www.ethanol-gec.org/clean/cf13.htm• www.eere.energy.gov/biomass/