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Energy from Waste and Biomass 11 Mar 2009, IOM3, London, UK. Energy from Algae. Steve Skill Plymouth Marine Laboratory scsk@pml.ac.uk. A Collaborative Centre of the. Plymouth Marine Laboratory. Multidisciplinary science. PML brings together :
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Energy from Waste and Biomass 11 Mar 2009, IOM3, London, UK . Energy from Algae Steve Skill Plymouth Marine Laboratory scsk@pml.ac.uk
A Collaborative Centre of the Plymouth Marine Laboratory Multidisciplinary science PML brings together: 100+ Professionals in biology, chemistry, maths and physics using the latest approaches in: novel technology, modelling, earth observations, virology, biogeochemistry, ecotoxicology, microbiology and molecular science. Innovation & Partnership Delivering pioneering marine research for 30 years.
PML- Bioenergy Research Focus • IPCC advisers on Carbon Capture & Storage • Pioneers of ocean fertilisation experiments • Algal physiology and biochemistry • Photobioreactor design & engineering • Metabolomics, Biochemical Identification, Bio-refineries and healthcare products • Molecular Biology and Transgenics • Algal virology • Biogas analysis and identification • Marine Microbiology • Photosynthetic wastewater treatment system design Supported by:
Bioenergy from Sewage • “The energy required to treat sewage is high and the water industry is the fourth most energy intensive sector in the UK”. (Parliamentary Office of Science and Technology, Postnote No. 282 April 2007). A schematic diagram of the activated sludge process
What a waste! • Nutrients (N & P) • Fixed C component [oxidised to CO2] • Heavy metals (Au, Pt, Cu, Zn, Cd etc) What a load of problems! • CO2 emissions • Nutrient discharges • Sewage sludge (hazardous waste) • Hormone disrupting chemicals (hermaphrodite fish!)
Global distribution of 400-plus systems that have scientifically reported accounts of being eutrophication-associated dead zones R. J. Diaz et al., Science 321, 926 -929 (2008) Global Nature of Eutrophication-Induced Hypoxia
How do you reduce CO2 emissions and energy use, and recover nutrients during sewage treatment? A: PHOTOSYNTHESIS (Algae)
Algae/bacterial wastewater treatment- Current Practice William J. Oswald Professor of Civil and Environmental Engineering, Emeritus Professor of Public Health, Emeritus Berkeley 1919 – 2005
Tertiary Treatment Biocoil PBR – Severn Trent, Stoke Bardolph, Nottingham (1993)
Wastewater treatment photobioreactors and direct fuelling of diesel engines with powdered algal biomass (1993)
Algal Biofilm wastewater treatment system applied to water recycling in intensive fish farming. (S. Skill 1999)
Algae Biofilm Sewage treatment Advantages • Low C footprint sewage treatment (Energy in v Sunlight) • Low carbon emission (oxidation v photosynthesis) • Single stage 2o, 3o & 4o treatment (inc.hormone degradation) • No sludge disposal • Not susceptible to biomass washout (flooding, extreme storm) • Simple dry biomass recovery (Biofuel + nutrient feedstock) Drawbacks • Land area • Algal/bacterial ~0.25 – 0.4 kg/m2/day BOD • Activated Sludge ~3kg/m2/day BOD • Algal/bacterial/PBR systems will require 5-10 times the land area compared to activated sludge (excluding settling tanks). May be less!
Algal biomass conversion to fuels and chemicals 4 - 6kg of nitrogen per person per year. Compared to fast pyrolysis oil: Lower oxygen conten, Higher heating value, Lower carbon in char, Easier to upgrade, Tolerate high moisture content, Tolerate high ash content
Disadvantages • Ponds and raceways have lower productivity compared to closed PBRs. • Open to the atmosphere and therefore susceptible to contamination. • Successful cultivation limited to a few extremophile strains • Low culture density • Advantages • Low capital cost • Low running costs (paddle wheel or passive wind mixing • Atmospheric CO2
R&D required PhotobioreactorEngineering Technology Obstacles • Leakage • Fouling • Oxygen removal • Contamination • Temperature control • High Capital Cost • Operating costs • Gas Injection • Robustness Biocoil Photobioreactors 1994
Wanted! Algae strains with: • Robustness • High Growth rate • Thermophilic capability • High Lipid content at max growth rate • Resistance to invasion • Self harvesting • NOx, SOx and High [CO2] tolerannce • Amenable to transgenics >5 years R&D required
R&D Focus Algal Microbiology - Biochemistry • Engineer strains to produce to produce and accumulate high levels of lipids during exponential growth. • Focus on non-oleagenous microalgal strains with high temp, NOx, SOX, High CO2 tolerant strains exhibiting autoflocculation.
R&D Focus Increasing Photosynthetic Efficiency • Reduce heat dissipation • Low sunlight utilization efficiency due to light harvesting complexes • Modify photosynthetic antennae • Increase photosynthetic efficiency to > 10%
Thank you Steve Skill scsk@pml.ac.uk Non-commercial support by: