Unit title:
Ventilation and Cooling; Water and Waste
Presentation title: Can human sewage provide the
feedstock for biodiesel production by photoautotrophic
microalgae?
Unit number:
A3
Unit date:
November12th 2008
Presentation date: January 11th 2008
Student name:
Craig Embleton
Student number:
0750553
Seminar group:
1 (Melissa Taylor)
e-mail:
admin@greenfrontier.org
website:
www.greenfrontier.org
CAN HUMAN SEWAGE
PROVIDE THE FEEDSTOCK
FOR BIODIESEL PRODUCTION
BY PHOTOAUTOTROPHIC
MICROALGAE?
Contents
• Problems with current situation
Sewage pollution
Conventional biofuels
• Sewage treatment
Waste stabilisation ponds
• Aquatic Species Programme
• Algae production
Raceway ponds
• Oil yield comparison
• Conclusions
• Questions
What are the problems?
The usual suspects:
• Climate change caused by burning fossil
fuels
• Peak oil
Plus
• Sewage pollution wrecks aquatic
ecosystems and human health
• Conventional biofuel production wrecks
terrestrial ecosystems and competes with
food production
Marine pollution
‘Discharge of untreated domestic wastes is a
major source of marine pollution, and
perhaps the most serious problem within the
framework of the Global Programme of
Action’.
Source: United Nations Environment Programme
report into the state of the marine
environment, 2006
1.5 million deaths/year from diarrhoeal
diseases attributable to poor sanitation
and hygiene
.’
Children playing near sewage outlets
Source: United Nations Environment Programme, 2006,
WHO, 2006
The Trouble with Conventional Biofuel
Indonesia currently has:
60,000 square kms of oil palm plantations
Plans for another 40,000 by 2015
dedicated to biofuel production alone.
Size of Wales: 21,588 square kilometres
• Rainforest destroyed.
• Huge amounts of fertilizers used.
• No reduction in greenhouse gases.
• Food prices up.
Source: Benemann, J 2008
Is there a solution?
Perhaps - Photoautotrophic Microalgae
Source: Shell, 2008
What nutrients do algal require to grow?
Algal Photosynthesis
106CO2 + 236H2O + 16NH4+ + HPO42-
C106H181O45N16P + 118O2 + 171H2O + 14H+
Major Nutrients: Nitrogen and Phosphorus
Source: Mara, D 2004
What nutrients are in human waste?
(Per person per day)
Per adult per
day
Faeces
Urine
Nitrogen
3g
8g
Phosphorus
2g
2g
Potassium
1g
2g
Calcium
2g
2g
Source: Harper, P. and Halestrap, L. 1999
Waste Stabilisation Ponds
Source: Benemann, J 2008
Sewage treatment: algal-bacterial
mutualism in waste stabilisation ponds
BOD =
Biochemical
Oxygen
Demand
Source: Mara, 2004
Aquatic Species Programme (ASP)
U.S. Department of Energy’s Office of Fuels
Development funded the ASP that ran from
1978-1996
• Focussed on production of biodiesel from
algae grown in ponds, using waste CO2 from
coal-fired power plants.
• The early studies used sewage ponds.
• Later studies used fresh and marine water
ponds with the addition of agricultural
fertilizers.
Source: Sheehan, J et al 1998
Aquatic Species Programme (ASP)
Programme concluded:
Many R&D obstacles but in theory 2,000 square
kilometres of climatically suitable land areas in
the U.S. could produce one quadrillion
(1,000,000,000,000) British Thermal Units (BTU)
of fuel.
Programme stopped for economic reasons.
CHEAP OIL!
Source: Sheehan, J et al 1998
Oil yields of crops
Crop
Maize
Soybean
Oil yield (L/ha)
172
446
Oil seed rape
1190
Jatropha
Oil palm
Microalgae grown in
raceway ponds.
1892
5950
17,000
Source: Chisti, Y 2007 and J. Benemann, J 2008
Most algae commercially produced in
raceway ponds (Arial View)
Source: Chisti, Y 2007
Most algae commercially produced in
raceway ponds as premium food
Because commercially produced algae is
usually a premium foodstuff e.g. spirulina
• Wastewater (sewage) is avoided.
• Expensive agricultural fertilizers used.
• Carbonated drinks quality carbon dioxide
added.
Algae harvested from waste stabilisation
ponds
Because algal product is a non-food crop:
• Wastewater (sewage) can be used.
• Expensive agricultural fertilizers
avoided.
• No addition of CO2 needed but could
use flue gases from fossil fuel power
stations.
Fuel from sewage pond algae
Proof of concept by Aquaflow
Powered a vehicle with a 5% biofuel mix
Source: Aquaflow 2008
Conclusions
CAN HUMAN SEWAGE
PROVIDE THE FEEDSTOCK
FOR BIODIESEL PRODUCTION
BY PHOTOAUTOTROPHIC
MICROALGAE?
Yes – but not yet economically.
Much more research needed and
tax breaks.
Issues - Does algal-biodiesel really not
compete with food production?
General composition of different human food
sources and algae (% of dry matter)
Commodity Protein
Carbohydrate
Lipid
Meat
43
1
34
Milk
26
38
28
Rice
8
77
2
Spirulina
maxima
60–71
13–16
6–7
Source: Spolaore, P et al, 2005
Issues - Will algal biodiesel perpetuate our
oil addiction?
• What about electric cars?
• What about transitioning to a low carbon
economy?
• How about using algae to capture carbon
and incorporate in soil or bury?
Questions?
Bibliography
• Aquaflow bionomic corporation limited. (2008). Prospectus
and investment statement for aquaflow bionomic
corporation limited. Available:
http://www.aquaflowgroup.com/documents/ProspectusandI
nvestmentStatement_001.pdf. Last accessed 31
December 2008.
• Benemann, J. (2008). Open ponds and closed
photobioreactors – comparative economics. Available:
http://www.bio.org/ind/wc/08/breakout_pdfs/20080430/Trac
k1_ContinentalA/Session9_230p400pm/Benemann_Contin
ental_A_Wed.pdf. Last accessed 1 January 2009.
• Broere, W. (2008). Harvesting energy from algae.
Available: http://wwwstatic.shell.com/static/aboutshell/downloads/swol/jan_mar_
2008/algae/algae_en.pdf. Last accessed 30 December
2008.
Bibliography Continued
•
•
Catherine Brahic. (2008). Europe unveils ambitious energy
plan . Available:
http://www.newscientist.com/article/dn13218-europeunveils-ambitious-energy-plan.html. Last accessed 27
December 2008.
Coordination Office of the Global Programme of Action for
the Protection of the Marine Environment from Land-based
Activities (gpa) of the United Nations Environment
Programme. (2006). The State of the Marine Environment.
Available: http://www.gpa.unep.org/documents/soe__trends_and_english.pdf. Last accessed 26 December
2008
Bibliography Continued
•
•
•
Harper, P. and Halestrap, L. (1999) Lifting the Lid. Powys,
CAT.
Mara, D (2004). Domestic Wastewater Treatment in
Developing Countries. London: Earthscan. 3. Available
(preview)
http://books.google.co.uk/books?id=d9O9Gw_3rOUC&pri
ntsec=frontcover&source=gbs_summary_r&cad=0 Last
accessed 27 December 2008.
Pearce, F. and Aldhous, P.. (2007). Is the biofuel dream
over?. Available:
http://www.newscientist.com/article/mg19626343.800.
Last accessed 23 December 2008.
Bibliography Continued
•
•
•
Sheehan, J., T. Dunahay, J. Benemann, and P. Roessler
(1998). A Look Back at the U.S. Department of Energy’s
Aquatic Species Program-Biodiesel from Algae. U.S.
Department of Energy’s Office of Fuels Development.
Prepared by the National Renewable Energy Laboratory,
Golden, Colorado . Available:
http://www1.eere.energy.gov/biomass/pdfs/biodiesel_from_
algae.pdf. Last accessed 20 November 2008
Spolaore, P., Joannis-Cassan, C., Duran, E., and Isambert,
A. (2006). Commercial applications of microalgae. Journal
of Bioscience and Bioengineering, 101(2):87-96.
World Health Organisation. (2006). Analysis of estimates of
the environmental attributable fraction, by disease.
Available:
http://www.who.int/entity/quantifying_ehimpacts/publication
s/preventingdisease5.pdf. Last accessed 27 December
2008.