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General Update. Bojan Tamburic. Investigating the pO 2 /pH 2 electrode. Sparge with H 2 ≈ 30ml/min. Natural rise up to pH 2 = 23.0%. Max pO 2 = 48.3%. Flush with He. Suspected temperature variations. Flush with He. Switch probe polarity to pO 2. Stop H 2 sparging, pH 2 = 10.1%.
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GeneralUpdate Bojan Tamburic
Investigating the pO2/pH2 electrode Sparge with H2 ≈ 30ml/min Natural rise up to pH2 = 23.0% Max pO2 = 48.3% Flush with He Suspected temperature variations Flush with He Switch probe polarity to pO2 Stop H2 sparging, pH2 = 10.1% Stop He flushing, min pO2 = 8.2% pO2 pH2 Switch probe polarity to pH2 Stop He flushing, min pH2 = 7.3%
Investigating the pO2/pH2 electrode Probe instability T stabilisation Switch to pH2 Flush with He Sparge H2 pO2 recovery pO2 recovery pO2 pH2 Flush with He Sparge H2
Transfer report outline Literature review • H2 production • Photosynthetic H2 production • Parameters affecting algal growth • Parameters affecting H2 production • Photobioreactor systems Experimental Method • Growing C.reinhardtii • Measuring growth and H2 production kinetics • Sartorius reactor: calibration and improvement • Sulphur deprivation procedure • Flat plate bioreactor design Results • C.reinhardtii growth in the column reactors • Growth kinetics in the Sartorius reactor • Stirred-tank batch reactor H2 production results • Sartorius H2 production results
Research paper summary Review of results HYSYDAYS Turin paper Rewrite? Photobioreactor design & Algal comparative study Locked up with WHEC Essen abstracts Release? Good at: Controlling light intensity, agitation, sparging Measuring OD, pH, pO2 Not good at: Measuring H2 Growth kinetics experiment
Growth kinetics experiment Algal strain = CC-124 Temperature = 25°C Agitation = 40% Light intensity = 20% Algal strain = CC-124 under dilution Temperature = 20°C Agitation = 50% Light intensity = 44% K = 0.345 r = 0.0720 t0 = 29.3 K = 0.432 r = 0.0523 t0 = 35.6
Growth kinetics experiment CC-124 growth OD as a function of time at various light intensities Determine optimal OD OD as a function of light intensity
Growth kinetics experiment CC-124 growth OD as a function of time at various agitation rates CC-124 growth OD as a function of time with and without CO2 sparging
WHEC 2010 abstracts Design of a novel flat-plate photobioreactor system for green algal hydrogen production B. Tamburic, F.W. Zemichael, G.C. Maitland, K. Hellgardt A comparative study of hydrogen production by selected Chlamydomonas strains B. Tamburic, F.W. Zemichael, S. Burgess, M. Boehm, K. Hellgardt, P.J. Nixon Some unicellular green algae have the ability to photosynthetically produce molecular hydrogen using sunlight and water. This renewable, carbon-neutral process has the additional benefit of sequestering carbon dioxide during the algal growth phase. The main costs associated with this process result from building and operating a photobioreactor system. The challenge is to design an innovative and cost effective photobioreactor that meets the requirements of algal growth and sustainable hydrogen production. We document the details of a novel 1 litre vertical flat-plate photobioreactor that has been designed to accommodate green algal hydrogen production at the laboratory scale. Coherent, non-heating illumination is provided by a panel of cool white LEDs. The reactor body consists of two compartments constructed from transparent polycarbonate sheets. The primary compartment holds the algal culture, which is agitated by means of a recirculating gas flow. A secondary compartment is filled with water and used to control the temperature and wavelength of the system. The reactor is fitted with instruments that monitor the pH, pO2, temperature and optical density of the culture. A membrane inlet mass spectrometry system has been developed for hydrogen collection and in-situ monitoring. The reactor is fully autoclaveable and the possibility of hydrogen leaks has been minimised. The modular nature of the reactor allows efficient cleaning and maintenance. Some unicellular green algae, such as Chlamydomonas, have the ability to photosynthetically produce molecular hydrogen under anaerobic conditions. They offer a biological route to renewable, carbon-neutral hydrogen production from two of nature’s most plentiful resources – sunlight and water. This process provides the additional benefit of carbon dioxide sequestration and the option of deriving valuable products from algal biomass. The aim of this study is to analyse the hydrogen production rates of green algae, focusing on multiple strains of Chlamydomonas, including several laboratory wild types, marine species and diverse mutant strains. Hydrogen production is initially screened by water displacement measurement in a 300ml batch photobioreactor with the aim of conducting a preliminary comparison and identifying promising strains for further study. Selected strains are analysed in a 3l tubular flow photobioreactor featuring a large surface-to-volume ratio and excellent light penetration through the culture. Key parameters of the hydrogen production process are continuously monitored and controlled; these include pH, pO2, optical density, temperature, agitation and light intensity. A membrane inlet mass spectrometry system has been developed for hydrogen collection and in-situ monitoring.
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