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Bioethanol Production of 1 st and 2 nd Generation. 3 rd REBEL Partner Meeting, 27 May 2010 Sara Helmberger. Upper Austrian University of Applied Sciences Research and Development Ltd, Campus Wels. Content. Introduction World-leading bioethanol producing countries
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Bioethanol Productionof 1st and 2nd Generation 3rd REBEL Partner Meeting, 27 May 2010 Sara Helmberger Upper Austrian University of Applied Sciences Research and Development Ltd, Campus Wels
Content • Introduction • World-leading bioethanol producing countries • Bioethanol production of 1st and 2nd generation • Various possible feedstocks • Production and processing technologies 3rd REBEL Partner Meeting, 27 May 2010
Introduction • Fossil fuels are responsible for 73 % of the CO2 production in the atmosphere • Extreme contribution to global warming • Interest in development of methods, reducing green house gases • Bioethanol as alternative to petroleum-derived transportation fuels 3rd REBEL Partner Meeting, 27 May 2010
Definition Bioethanol • Ethyl alcohol, grain alcohol, CH3-CH2-OH or EtOH • = Liquid biofuel • Advantages, compared to gasoline:- higher octane number- broader flammability limits- higher flame speeds- higher heats of vaporization- higher compression ratio- shorter burn time • Possible feedstocks:plant oils, sugar beets, cereals, organic waste, processed biomass • Disadvantages, compared to gasoline:- lower energy density- its corrosiveness- low flame luminosity- lower vapor pressure - miscibility with water 3rd REBEL Partner Meeting, 27 May 2010
World-leading bioethanol producing countries • World-wide production of fuel ethanol more than tripled from 2000 until now • About 60% of global bioethanol production are obtained from sugar caneand 40% from other crops (e.g. maize) 3rd REBEL Partner Meeting, 27 May 2010
North American Ethanol production The United States are with over 41 % the world´s leader in ethanol production Feedstocks: maize wheat, barley, sorghum 3rd REBEL Partner Meeting, 27 May 2010 page 6
South American Ethanol prodution South America contributes with roughly 35 % to world´s ethanol production, with Brazil being the leader country Feedstock: sugar cane ~ 20 % exported to US, EU, others 3rd REBEL Partner Meeting, 27 May 2010 page 7
European Ethanol production Europe contributes with 9 % to world´s ethanol production-> Comparable to the US ethanol market of roughly ten years ago Plants in France, Spain, Sweden, UK, Austria (Pischelsdorf, Lower Austria) In 2000, the EU introduced a Biofuel Directive Commission of the European Communities (2007) -> binding minimal target of 10 % biofuels by 2020 Feedstock:wheat, sugar beet, waste from the wine industry 3rd REBEL Partner Meeting, 27 May 2010 page 8
European Ethanol production Bioethanol Plant in Pischelsdorf, Lower Austria 3rd REBEL Partner Meeting, 27 May 2010 page 9
Production technologyFeedstocks 3rd REBEL Partner Meeting, 27 May 2010 page 10
Bioethanol production of 1st generation Major feedstocks for world´s ethanol production: Sugar-containing feedstock: Sugar cane Starchy feedstock: Maize 3rd REBEL Partner Meeting, 27 May 2010 page 11
Bioethanol production of 1st generation Starchy materials (e.g. maize) US: 2 types of maize processing facilities:- Wet milling (since 1980s)- Dry grind (newer technology) Starch = a polysaccharide carbohydrate, with a large number of sugar-molecules Break down of the chains of this carbohydrate to obtain the single (individual) sugars -> Hydrolysis technique Fermentation with microorganisms (e.g. yeasts) 3rd REBEL Partner Meeting, 27 May 2010 page 12
Bioethanol production of 1st generation Sugar-containing feedstocks (e.g. sugar cane, beet molasses, sweet sorghum) provide the single sugars (e.g. sucrose, glucose and fructose), which can be readily fermented by microorganisms (yeast) -> no hydrolysis is necessary Brazil: sugar cane- harvest- pressing- Fermentation of sugar juice by microorganisms (yeast) Europe: Beet molasses Developing countries (e.g. Africa): Sweet sorghum 3rd REBEL Partner Meeting, 27 May 2010 page 13
Bioethanol production of 2nd generation Feedstocks: Alternative or lignocellulosic materials = non food crops:- waste and remnant biomass - stalks of wheat and corn- wood- grass- straw These most abundant reproducible feedstocks on Earth are of - high yields- low costs- good suitability for low quality land- low environmental impacts 3rd REBEL Partner Meeting, 27 May 2010 page 14
Bioethanol production of 2nd generation Lignocellulosic biomass 3 basic polymers:- Cellulose- Hemicelluloses - Lignin Processing of lignocellulosic material to bioethanol1. Pre-treatment2. Hydrolysis 3. Fermentation4. Product separation 3rd REBEL Partner Meeting, 27 May 2010 page 15
Bioethanol production of 2nd generation Pre-treatment Size-reduction Removal of structural and compositional impediments -> Lignocellulosic biomass is made more accessible for subsequent hydrolysis Pre-treatment possiblities:- mechanical- chemical - biological pre-treatment- “Steam Explosion” Steam Explosion:- Biomass is extruded at high temperature and pressure 3rd REBEL Partner Meeting, 27 May 2010 page 16
Bioethanol production of 2nd generation Pre-treatment: Steam Explosion 3rd REBEL Partner Meeting, 27 May 2010 page 17
Bioethanol production of 2nd generation Hydrolysis = Saccharification of lignocellulosic biomass Cellulose and Hemicellulose have to be broken down into single (individual) sugar molecules Catalyst: - dilute acid - concentrated acid - enzymes (so-called cellulases) Enzymatic hydrolysis- Cellulases are produced from both fungi and bacteria- Hydrolysis at mild conditions (50°C and pH 5.0)- Effective cellulose and hemicellulose breakdown 3rd REBEL Partner Meeting, 27 May 2010 page 18
Bioethanol production of 2nd generation Fermentation The hydrolysate (mixed sugar-solution) is then fermented by microorganisms (e.g. yeast) The sugar-solution contains not only one kind of sugar, but several different kinds-> Microorganisms are required, that can convert all sugars to high yields of EtOH Most effective producer of bioethanol: Saccharomyces cerevisiae- can ferment only one kind of sugar- metabolic engineered strain or adapted strain of yeast is required 3rd REBEL Partner Meeting, 27 May 2010 page 19
Bioethanol production of 2nd generation Product separation, Distillation Distillation - Bioethanol is separated from water - Ethanol is concentrated to about 95.6 % Value-added co-products (e.g. lactic acid)- processing into plastics or other products Lignin- usage in various value-added applications 3rd REBEL Partner Meeting, 27 May 2010 page 20
Bioethanolusage 3rd REBEL Partner Meeting, 27 May 2010 page 21
Thank you for your attention ! 3rd REBEL Partner Meeting, 27 May 2010 page 22