wh (emile) van zyl*1, r den haan1, sh rose1, m bloom1 · co-gasification of biomass with coal in a...
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CoER : Biofuels Department of Microbiology • Faculty of Natural Sciences
UNIVERSITEIT • STELLENBOSCH • UNIVERSITY
jou kennisvennoot • your knowledge partner
Advanced lignocellulose conversion
technologies for sustainable bioenergy
production in South(ern) Africa
WH (Emile) Van Zyl*1, R den Haan1, SH Rose1, M Bloom1,
JF Görgens2, and JH Knoetze2 Department of Microbiology, University of Stellenbosch,
Private Bag X1, Matieland 7602, South Africa
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Traditional role of bioenergy/ biofuels in southern Africa
Next generation technologies
Traditional bioenergy production in Africa
Share of total primary energy supply in Africa (2001) [Amigun et. al., 2006. Renew. Sust. Energ. Rev. 12:690-711]
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Availability of biomass (Malawi as example)
Malawi today Malawi in the past
Brick-making using woody materials Charcoal 4
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Biomass potential of Africa at large
Ratio of the energy content of the biomass on abandoned agriculture lands relative to the current primary energy demand at the country level. The energy content of biomass is assumed to be 20 kJ g−1. Source: Campbell et al. (2008)
CoER : Biofuels Department of Microbiology • Faculty of Natural Sciences
UNIVERSITEIT • STELLENBOSCH • UNIVERSITY
jou kennisvennoot • your knowledge partner
Senior Chair of Energy Research:
focusing on biomass conversion technologies
Emile van Zyl
Johann Gorgens, Marinda Bloom & Hansie Knoetze
[Stellenbosch University]
&
Harro von Blottnitz
[University Cape Town]
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CoER : Biofuels (members)
Microbiology
Chem Eng Proc Eng
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Cellulosics biofuels production value chain:
1. The CoER : Biofuels positions itself in the conversion technologies, but acknowledges the importance of establishing the whole value chain.
Technologies for Cellulose Conversion
Primary
Biomass
Production
Biomass
Transport
Biomass
Primary
Processing
Biomass
Conversion
to Biofuels
and By-
products
Product
Distribution
& Marketing
Thermo-
chemical
routes
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Lignocellulose
feedstock or
residue
Pyrolysis Pyrolysis
oils
Charcoal
Transportation
fuels
Catalytic
Upgrading Refining
Gasification
Product gas
or syngas
Syngas
Combustion for
heat/electricity
Product
gas
Synthesis Refining
Pretreatment Enzymatic
hydrolysis
Fermentation
to ethanol Distillation
Biological route
to cellulosic
ethanol
Cellulosic
ethanol
Residues for
thermo-chemical
conversion
Consolidated BioProcessing
Combustion
in boiler
High
pressure
steam
Surplus heat
Steam
turbine Electricity Biogas
Cooking fuel
Lignocellulosic Biomass Conversion Options
Research Objectives
Develop 2nd generation technologies for biofuels
microbial hydrolysis and fermentation
pyrolysis and gasification of lignocellulose
Process modelling and development of bio-refinery concepts
Scenario building, Techno-economic and Life Cycle Analysis of these technologies
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Microbial conversion of cellulose to ethanol
Sustainable Biofuels
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Ethanol production from sugar
Spent
yeast
Crashing
Sugar
extraction
Sugarcane\
Sugarbeet
Sweet
sorghum
Fuel
blending
Alcohol recovery
Distillation & dehydration
Storage
tank
Yeast
Fermentation
Technologies for Ethanol Production
Sugar
Storage
tank
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Ethanol production from cellulosics
Spent
material
Pre-treatment
Chipping
Grinding
Agric Res
Woody
Material
Grasses
Water
mixing
tank
Steam explosion
~200ºC
Cellulases
Fuel
blending
Saccharification
Alcohol recovery
Distillation & dehydration
Storage
tank
Yeast
Fermentation
Technologies for Ethanol Production
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Consolidated BioProcessing (CBP)
O O
O
O
O
Glu Man Gal
Xyl Ara
Ethanol + CO2
P T YFG
Glycosyl
Hydrolases
Technologies for Cellulose Conversion
Van Zyl et al. 2007. Adv. Biochem. Eng./Biotechnol. 108:205–235
La Grange et al. 2010. Appl. Microbiol. Biotechnol 87:1195–1208
Lynd et al. 2002. Microbiol. Mol. Biol. Rev. 66:506–577
Lynd et al. 2005. Curr. Opin. Biotechnol. 16:577–583
Rome, NY Pilot & Demonstration Plant
January 2008
November 2008 15
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Background strain
Appearance at 120 hrs.
CBP strain
0
10
20
30
40
50
60
0 50 100
Eth
ano
l co
ncent
ration
, g/
L
Time (hours)
CBP + 1 mg Xylanase
Background +BGL + Xylanase
Background + Cellulase + BGL + Xylanase
Mascoma CBP technology on 18% w/w paper sludge
Enzyme Reduction on Paper Sludge
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Pretreatment for Ethanol Production
Cellulose Lignin
Hemicellulose
Amorphous Region
Crystalline Region
Pretreatment
Pretreatment - produces an enzyme accessible substrate
Ladisch, 2006
Steamgun Pretreatment of Lignocellulose
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Thermochemical Technologies for Biofuel Production
Bioenergy potential in sub-Saharan Africa
Optimisation of fast, slow and vacuum pyrolysis with sugarcane bagasse, corn stover and eucalyptus for the production of charcoal, bio-oil, activated carbon and biochar
Co-gasification of biomass with coal in a Sasol-type process addressed in terms of differences in reactivity between biomass and coal, and how this affects the overall process performance.
This attempts to help SASOL in making biomass and technology choices towards utilizing up to 10% biomass as feedstock for the Fisher Tropsch process.
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Thermochemical processes
Process (biorefinery) modelling of both biological and thermochemical processes for optimisation of energy efficiency and as basis for economic assessments for 2nd generation biofuels production in SA.
Quantification of the economic risk associated with second generation biofuels production. This demonstrated that 2nd generation bio-ethanol production may be viable in SA.
Life cycle assessment to compare biological and thermochemical processes for conversion of lignocellulose to biofuels. This demonstrated that energy efficiency was critically important to maximise environmental benefits.
The CoER thus develop valuable expertise to assist industry in evaluation different technology combinations in pre-feasibility desktop studies.
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Life cycle analysis and modelling
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Integrating 1st and 2nd generation technologies could create
opportunities for sub-Saharan Africa
Bioenergy potential in sub-Saharan Africa
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Bioenergy value to southern Africa
1. Energy plays a key role in the development of nations and provides vital services and means that improve quality of life, the so-call engine of economic progress.
3. Renewable bioenergy, particularly biofuels, has played a pivotal role in Africa and could again help address the need for energy expansion and critical human needs in the foreseeable future.
2. With the sub-Saharan Africa population of about 800 million bound to reach >1.2 billion by 2020, living in poverty cannot be reduced without major improvements in the quality and magnitude of energy services in Africa.
1. In developed countries, the main thrust for ethanol production is the replacement of fossil fuels in the transportation sector.
2. Africa has a great potential to produce and meet the growing demand to phase-out fossil fuels for transport.
3. However, the situation is different for developing countries, such as the SADC region because of their unique socio-economic needs, especially:
a) the chronic food and energy insecurity;
b) extreme poverty;
c) high unemployment rate, and
d) degradation of the natural environment.
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Biofuel production in southern Africa
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[Ambali et al. 2011. A review of sustainable development of bioenergy in Africa: An outlook for the future bioenergy industry. Sci. Res. Essays 6: 1697-1708]
Biofuels production in southern Africa
Ethanol
[606 ML]
Sources: RAF Outlook (2007) and Hassan (2008).
Sugar
[10 Mt] [~3 BL EtOH]
(50%) [331 ML]
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Opportunities for sugarcane in SADC
1. Currently, Africa only produce a fraction of the world ethanol, and even Africa’s sugar production is rather modest with South Africa been the biggest producer, producing about half of the sugarcane in SADC (~20 Mt/annum), using an area of ~325 000 Ha!
2. However, a recent study (Watson, 2011) estimated that about 6 MHa of arable land in SADC countries (primarily Mozambique, Angola, Tanzania, Zambia, Zimbabwe and Malawi) are suitable for sugarcane production at an average yield of >65 t/Ha or more.
3. Conservatively, this means that the total South Africa sugar industry can be replicated every year for at least 15 -20 years in southern Africa!
[Watson, HK. 2011. Potential to expand sustainable bioenergy from sugarcane in southern Africa. Energy Policy 39: 5746–5750.]
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2.3M 1.1M
0.21M
0.47M
1.2M
0.62M
0.33M
Potential sugarcane production in southern Africa
[Watson. 2011. Potential to expand sustainable bioenergy from sugarcane in southern Africa. Energy Policy in press (doi: 10.1016/j.enpol.2010.07.035).]
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Opportunities for sugarcane in SADC
1. Currently, Africa is producing 331 ML;
2. If 50% of the total current sugar production is converted to ethanol, Africa can producing 3 BL, five time more!;
3. However, if optimal sugarcane is produced in 6 SADC countries only and about 50% of total biomass converted to biofuels, the potential can increase with another order of magnitude, +35 BL, representing ~10-13% of Africa’s total petroleum consumption!
4. Theoretically, Africa is producing at present only 1% of its potential and can, together with Brazil, be a major player in the future!
African Continental Convention on Global Sustainable Bioenergy
17 - 19 MARCH 2010
STELLENBOSCH LODGE, STELLENBOSCH
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GSB AFRICAN
CONVENTION
As the world considers paths to a sustainable future and the role of bioenergy in this context, Africa brings important assets and wants to be an active partner. However, Africa needs to ensure that bioenergy development is implemented in a way that contributes to critical human needs.
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GSB AFRICAN
CONVENTION
Bioenergy Resolution for Africa (Draft)
Actions need to be taken to ensure that Africa benefits along the full value chain of bioenergy supply and utilisation. These include, among many worthy actions, development of:
1. More analysis, understanding, and consensus on the potential of bioenergy to realize a sustainable Africa;
2. African scalable demonstration projects using latest state of the art technologies and African raw materials for learning perspectives e.g. training to strengthen local manpower;
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GSB AFRICAN
CONVENTION
Bioenergy Resolution for Africa (Draft)
Actions need to be taken (continued):
3. Needed human capacity and career opportunities, including creating an African intellectual base, reducing brain drain and engaging existing African traditional knowledge systems;
4. The institutional resources to foster coordination across Africa for stakeholder interaction, and suitable strategies, policies and initiatives;
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GSB AFRICAN
CONVENTION
Bioenergy Resolution for Africa (Draft)
Actions need to be taken (continued):
5. Pilot projects to show best practices in energy efficiency and resource protection in transport, electricity supply, cooking and other household needs;
6.International, regional and local policies on trade, aid, land tenure, and development needs to be aligned now to develop integrated value chains of agriculture and forestry for food and bioenergy in Africa.
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GSB AFRICAN
CONVENTION
Bioenergy Resolution for Africa (Draft)
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Strategic partnership with NEPAD
Ibrahim Mayaki
Mosad Elmissiry Jeremy Woods
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Future for Africa??
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Sustainable biofuel production in Africa
Thank you!