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Progress in biofixation of CO2 from combustion flue gas by microalgae
微藻固定燃烧烟气中CO2 的研究进展

Yixin Zhang,Bingtao Zhao,Kaibin Xiong,Zhongxiao Zhang,Xiaohong Hao,Tao Liu,

生物工程学报 , 2011,
Abstract: Global warming caused by the increasing CO2 concentration in atmosphere is a serious problem in the international political, economic, scientific and environmental fields in recent years. Intensive carbon dioxide capture and storage (CCS) technologies have been developed for a feasible system to remove CO2 from industrial exhaust gases especially for combustion flue gas. In these technologies, the biofixation of CO2 by microalgae has the potential to diminish CO2 and produce the biomass. In this review, the current status focusing on biofixation of CO2 from combustion flue gases by microalgae including the selection of microalgal species and effect of flue gas conditions, the development of high efficient photobioreactor and the application of microalgae and its biomass product were reviewed and summarized. Finally, the perspectives of the technology were also discussed.
Biofixation of Carbon dioxide by Chlamydomonas sp. in a Tubular Photobioreactor  [cached]
H Hadiyanto,S Sumarno,Rufaida Nur Rostika,Noer Abyor Handayani
International Journal of Renewable Energy Development (IJRED) , 2012,
Abstract: The biogas production from anaerobic digestion is a potential fuel for power generators application, if biogas can be upgraded to the same standards as fossil natural gas by CO2, H2S, and other non-combustible component removal. Microalgae Chlamydomonas sp. has potency to biofix the carbon dioxide and can be used as an additional food ingredient. The variations of flow rate and carbon dioxide concentration in the process resulting different value of biomass production and carbon dioxide biofixation. Biomass production at 40% carbon dioxide concentration obtained 5.685 gr/dm3 at 10% carbon dioxide concentration obtained 4.892 gr/dm3. The greatest value of carbon dioxide absorption occurs at a 40% concentration amounting to 12.09%. The rate of growth and productivity of microalgae tend to rise in 10% and 20% (%v) carbon dioxide concentration, but began started a constant at 30% and 40% (%v) carbon dioxide concentration. Biomass production tends to increase in light conditions while a constant in dark conditions. This study used Chlamydomonas sp. as media culture and performed on bubble column and tubular reactor with 6 litres of culture medium at a temperature of 28oC and atmospheric pressure.
Anondho Wijanarko,Dianursanti,Arief Budi Witarto,Roekmijati Widaningroem Soemantojo
Makara Seri Teknologi , 2004,
Abstract: To reduce the level of CO2 content in air, effort on converting CO2 to useful products is required. One of the alternatives includes CO2 fixation to produce biomass using Chlorella vulgaris Buitenzorg. Chlorella vulgaris Buitenzorg is applied for production of food supplement. Chlorella vulgaris Buitenzorg is also easy to handle due to its superior adaptation. Currently, Chlorella vulgaris Buitenzorg has been analyzed by some experts for its cellular composition, its ability to produce high quality biomass and the content of essential nutrition. A series of experiments was conducted by culturing Chlorella vulgaris Buitenzorg using Beneck medium in bubbling column photobioreactor. The main variation in this experiment was photoperiodicity, where growth of Chlorella vulgaris Buitenzorg was examined during photoperiodicity condition. The difference between CO2 gas concentration of inlet and outlet of the reactor during operational period, was compared to the same experiment under continuous illumination. Under photoperiodicity of 8 and 9 h/d, the culture cell densities (N) were approximately 40 % higher than under continuous illumination. Final biomass density of Chlorella vulgaris Buitenzorg at 9 h/d illumination was 1.43 g/dm3, around 46% higher than under continuous illumination. Specific carbon dioxide transfer rate (qCO2) in photoperiodicity was 50-80% higher than under continuous illumination. These experiments showed that photoperiodicity affects the growth of Chlorella vulgaris Buitenzorg The specific growth rate (μ) by photoperiodicity was higher than that by continuous ilumination while the growth period was two times longer. Based on the experiments, it can be concluded that photoperiodicity might save light energy consumption. The prediction of kinetic model under continuous illumination as well as under photoperiodicity illumination showed that Haldane model became the fitted kinetic model.
Effects of Air Flow Rate and CO2 Concentration on the Growth of Nannochloropsis sp. and EPA Accumulation in an Airlift Photobioreactor
通气量和CO2对Nannochloropsis sp.在光生物反应器中的生长和EPA合成的影响

XU Fang,HU Han-hua,CONG Wei,CAI Zhao-ling,OUYANG Fan,

过程工程学报 , 2004,
Abstract: The effects of air flow rate and concentration of CO2on the growth of Nannochloropsis sp. cells as well as EPA content in an airlift photobioreactor were investigated. The results show that Nannochloropsis sp. grew faster in the airlift photobioreactor than in the flask. After 8 d culture, the biomass of Nannochloropsis sp. in the airlift photobioreactor reached 857 mg/L, which was 2-fold of that obtained in the flask. The growth rate increased with the increase of air flow rate. Nannochloropsis sp. grew the fastest at the air flow rate of 500 mL/min and no positive effect on the cell growth was observed above this flow rate. 1% (?) CO2 added in the air promoted the growth of Nannochloropsis sp. significantly, thereby the maximal growth rate was 1.8-fold of that without CO2 addition. The highest EPA yield of the culture, 39.0 mg /L, was obtained at the air flow rate of 400 mL/min with 0.5% (?) CO2.
Nkongolo Mulumba,Ihab H. Farag
International Journal of Engineering Science and Technology , 2012,
Abstract: Biodiesel production from algae is a promising technique. Microalgae have the potential to produce 5,000-15,000 gallons of biodiesel/(acre-year). However, there are challenges; these include high yieldof algae biomass with high lipid content and the effective technique to harvest the grown algae, extract the algal oil and transesterify the oil to biodiesel. In this project Tubular PhotoBioReactor (TPBR) was designed and achieved a ten times increase in algae concentration. It produced 1g of dry algal biomass per liter of medium within 12 days, with a lipid content of 12% approximately. Healthy algal culture grew well in the TPBR reaching 56x106 cells/mL of culture medium. The 10 fold increase is higher than those reported for open ponds and helical photobioreactor.
Average Light Intensity Inside a Photobioreactor
Herby Jean
Undergraduate Journal of Mathematical Modeling : One + Two , 2011, DOI: 10.5038/2326-3652.4.1.9
Abstract: For energy production, microalgae are one of the few alternatives with high potential. Similar to plants, algae require energy acquired from light sources to grow. This project uses calculus to determine the light intensity inside of a photobioreactor filled with algae. Under preset conditions along with estimated values, we applied Lambert-Beer's law to formulate an equation to calculate how much light intensity escapes a photobioreactor and determine the average light intensity that was present inside the reactor.
Conteúdo lipídico e composi??o de ácidos graxos de microalgas expostas aos gases CO2, SO2 e NO
Radmann, Elisangela Martha;Costa, Jorge Alberto Vieira;
Química Nova , 2008, DOI: 10.1590/S0100-40422008000700002
Abstract: the objective of the present work was to verify the lipid content and the fatty acid composition of the microalgae spirulina sp., scenedesmus obliquus, synechococcus nidulans and chlorella vulgaris cultivated in a medium containing co2, so2 and no. the microalga scenedesmus obliquus presented the highest lipid content (6.18%). for the other microalgae the lipid content ranged from 4.56 to 5.97%. the major monounsaturated fatty acids content was 66.01% for s. obliquus. the pufa were obtained in major amount by the microalgae spirulina sp. (29.37%) and s. nidulans (29.54%). the palmitoleic acid was in larger amount, with 41.02% concentration (spirulina sp.).
An integrated photobioreactor system for the production of Spirulina platensis  [PDF]
Suphi S. Oncel,Oguz Akpolat
Biotechnology , 2006,
Abstract: In this study, a laboratory scale integrated type of a photobioreactor system was operated for the production of Spirulina platensis. The integrated design consisted of a tank unit for the main production site and a helical coil unit for the main illumination site. Different trials were made in order to select the best illumination mode. The best illumination mode was the sequential mode where a continuous illumination was taking place in the internally illuminated tank unit and at the same time a 12/12 h light dark cycle was going on, in the coil unit. The system maintain the stability in the pH levels and a cell concentration of 3.12 g L-1 on dry weight basis. After the selection of the illumination mode the best flow rate and light intensity synchronization was tested by applying various combinations of intensities and flow rates in the coil unit. The best values were obtained with the 11000 lux intensity at 7 cm sn-1 flow rate in the coil unit reaching a growth rate of 0.42 day. The determination of the best conditions for the working of the integrated system was one of the main objectives of this study. Also to focus on an integrated system that could be used in commercial scale, that could succeed the need of high volume production at the same time to fulfill the need of light compensating the dark regions that could happen in the big tanks like commercial fermenters with outdoor or indoor helical tubular units as photostages.
Switchable Gene Expression in Escherichia coli Using a Miniaturized Photobioreactor  [PDF]
Jae Myung Lee, Junhyeong Lee, Taesung Kim, Sung Kuk Lee
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0052382
Abstract: We present a light-switchable gene expression system for both inducible and switchable control of gene expression at a single cell level in Escherichia coli using a previously constructed light-sensing system. The λ cI repressor gene with an LVA degradation tag was expressed under the control of the ompC promoter on the chromosome. The green fluorescent protein (GFP) gene fused to a λ repressor-repressible promoter was used as a reporter. This light-switchable system allows rapid and reversible induction or repression of expression of the target gene at any desired time. This system also ensures homogenous expression across the entire cell population. We also report the design of a miniaturized photobioreactor to be used in combination with the light-switchable gene expression system. The miniaturized photobioreactor helps to reduce unintended induction of the light receptor due to environmental disturbances and allows precise control over the duration of induction. This system would be a good tool for switchable, homogenous, strong, and highly regulatable expression of target genes over a wide range of induction times. Hence, it could be applied to study gene function, optimize metabolic pathways, and control biological systems both spatially and temporally.
Comparison between Airlift Photobioreactor and Bubble Column for Skeletonema Costatum Cultivation  [cached]
Saranya Monkonsit,Sorawit Powtongsook,Prasert Pavasant
Engineering Journal , 2011, DOI: 10.4186/ej.2011.15.4.53
Abstract: The cultivation of diatom Skeletonema costatum was achieved in airlift photobioreactor and the system performance was compared to that of bubble column. The standard F/2 medium (Guillard’s medium) for typical diatom cultivation could only yield the best growth character when the silicon concentration increased 4 times the normal value. In terms of cell growth, the airlift photobioreactor provided better performance than the bubble column where the maximum cell concentration, specific growth rate, and productivity in the airlift were 4.6 x 106 cell mL-1, 0.07 h-1, and 6.4 x 104 cell s-1 compared with 1.8 x 106 cell mL-1, 0.04 h-1, and 2.2 x 104 cell s-1 in the bubble column of the same size (3L) and operated at the same aeration rate (superficial velocity = 1.5 cm s-1) and light intensity (34 μmol photons m 2 s 1). This was because the airlift photobioreactor allowed circulatory flow in the system which helps prevent cell precipitation and enhance light utilization efficiency. The optimal operating conditions in the airlift system which was found most optimal to cell growth were: the ratio between downcomer and riser cross sectional area (Ad:Ar) of 3.27, superficial gas velocity 1.5 cm s 1 and the light intensity 34 μmol photons m 2 s 1. Preliminary economical assessment on the cultivation of S. costatum in airlift system compared with that in bubble column was carried out, whereas the analysis for nutritional values of the obtained biomass indicated relatively high protein content.
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