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Arief Widjaja
Makara Seri Teknologi , 2009,
Abstract: Recently, several strains of microalgae have been studied as they contain high lipid content capable to be converted to biodiesel. Fresh water microalgae Chlorella vulgaris studied in this research was one of the proof as it contained high triacyl glyceride which made it a potential candidate for biodiesel production. Factors responsible for good growing of microalgae such as CO2 and nitrogen concentration were investigated. It was found that total lipid content was increased after exposing to media with not enough nitrogen concentration. However, under this nitrogen depletion media, the growth rate was very slow leading to lower lipid productivity. The productivity could be increased by increasing CO2 concentration. The lipid content was found to be affected by drying temperature during lipid extraction of algal biomass. Drying at very low temperature under vacuum gave the best result but drying at 60oC slightly decreased the total lipid content.
Microalgae Lipid and Biodiesel Production: A Brazilian Challenge  [PDF]
Carolina T. Miranda, Roberta F. Pinto, Daniel V. N. de Lima, Carolina V. Viegas, Simone M. da Costa, Sandra M. F. O. Azevedo
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.615254
Abstract: Global increases in atmospheric CO2 and climate change are drawing considerable attention to identify sources of energy with lower environmental impact than those currently in use. Biodiesel production from microalgae lipids can, in the future, occupy a prominent place in energy generation because it represents a sustainable alternative to petroleum-based fuels. Several species of microalgae produce large amounts of lipids per biomass unit. Triacylglycerol is the fatty acid used for biodiesel production and the main source of energy reserves in microalgae. The current literature indicates that nutrient limitations can lead to triacylglycerol accumulation in different species of microalgae. Further efforts in microalgae screening for biodiesel production are needed to discover a native microalgae that will be feasible for biodiesel production in terms of biomass productivity and oil. This revision focuses in the biotechnological potential and viability of biodiesel production from microalgae. Brazil is located in a tropical region with high light rates and adequate average temperatures for the growth of microalgae. The wide availability of bodies of water and land will allow the country to produce renewable energy from microalgae.
Current Status and Prospects of Biodiesel Production from Microalgae  [PDF]
Xiaodan Wu,Rongsheng Ruan,Zhenyi Du,Yuhuan Liu
Energies , 2012, DOI: 10.3390/en5082667
Abstract: Microalgae represent a sustainable energy source because of their high biomass productivity and ability to remove air and water born pollutants. This paper reviews the current status of production and conversion of microalgae, including the advantages of microalgae biodiesel, high density cultivation of microalgae, high-lipid content microalgae selection and metabolic control, and innovative harvesting and processing technologies. The key barriers to commercial production of microalgae biodiesel and future perspective of the technologies are also discussed.
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.
Microalgae Isolation and Selection for Prospective Biodiesel?Production  [PDF]
Van Thang Duong,Yan Li,Ekaterina Nowak,Peer M. Schenk
Energies , 2012, DOI: 10.3390/en5061835
Abstract: Biodiesel production from microalgae is being widely developed at different scales as a potential source of renewable energy with both economic and environmental benefits. Although many microalgae species have been identified and isolated for lipid production, there is currently no consensus as to which species provide the highest productivity. Different species are expected to function best at different aquatic, geographical and climatic conditions. In addition, other value-added products are now being considered for commercial production which necessitates the selection of the most capable algae strains suitable for multiple-product algae biorefineries. Here we present and review practical issues of several simple and robust methods for microalgae isolation and selection for traits that maybe most relevant for commercial biodiesel production. A combination of conventional and modern techniques is likely to be the most efficient route from isolation to large-scale cultivation.
Microalgae of Odisha Coast as a Potential Source for Biodiesel Production
World Environment , 2012, DOI: 10.5923/j.env.20120201.03
Abstract: In recent years microalgae have been proved as the potential source for biodiesel production due to high oil content. In the present study three brackish water microalgal strains (Chlorococcum sp., Chlorella sp. and Scenedesmus sp.) of Odisha coast were screened for the suitability for biodiesel production. Among all, Scenedesmus sp. seems to be the best one for high lipid productivity (24.66mg/L/day) with high biomass yield of 0.9g/L at stationary phase. Also the Scenedesmus sp. possesses the most adequate fatty acid profile. The present study suggested that Scenedesmus sp. is appropriate for biodiesel production for its high lipid content; this strain was selected for higher scale studies.
Cultivating Microalgae in Domestic Wastewater for Biodiesel Production  [cached]
Notulae Scientia Biologicae , 2012,
Abstract: The objective of this study was to evaluate the growth of nine species of microalgae (green and blue green microalgae) on domestic waste water samples obtained from Zenein Waste Water Treatment Plant (ZWWTP), Giza governorate, Egypt. The species were cultivated in different kind of waste water; before treatment; after sterilization; with nutrients with sterilization and with nutrients without sterilization. The experiment was conducted in triplicate and cultures were incubated at 25±1°C under continuous shaking (150 rpm) and illumination (2000 Lux) for 15 days. pH, electric conductivity (EC), optical density (OD) , dry weight (DW), were done at the time of incubation and at the end of experiment, in addition to determine the percentage of lipid and biodiesel. The data revealed that, domestic waste water with nutrient media (T3) was promising for cultivation of five algal species when compared with conventional media, Moreover, domestic waste water after sterilization (T2) was selected media for cultivation of Oscillatoria sp and Phormedium sp. However, T1 media (waste water without treatment) was the promising media for cultivation of Nostoc humifusum. The biodiesel produced from algal species cultivated in waste water media ranged from 3.8 to 11.80% when compared with the conventional method (3.90 to 12.52%). The results of this study suggest that growing algae in nutrient rich media offers a new option of applying algal process in ZWWTP to mange the nutrient load for growth and valuable biodiesel feedstock production.
Prospective of biodiesel production utilizing microalgae as the cell factories: A comprehensive discussion
NM Verma, S Mehrotra, A Shukla, BN Mishra
African Journal of Biotechnology , 2010,
Abstract: Microalgae are sunlight-driven miniature factories that convert atmospheric CO2 to polar and neutral lipids which after esterification can be utilized as an alternative source of petroleum. Further, other metabolic products such as bioethanol and biohydrogen produced by algal cells are also being considered for the same purpose. Microaglae are more efficient than the conventional oleaginous plants in capturing solar energy as they have simpler cellular organization and high capacity to produce lipids even under nutritionally challenged and high salt concentrations. Commercially, microalgae are cultivated either in open pond systems or in closed photobioreactors. The photobioreactor systems including tubular bioreactors, plate reactors and bubble column reactors have their own advantages as they provide sterile conditions for growing algal biomass. Besides, other culture conditions such as light intensity, CO2 concentration, nutritional balance, etc, in closed reactors remain controlled. On the other hand, though the open ponds provide a cost-effective option to utilize natural light facility for algal cells, the tough maintenance of optimal and stable growth conditions makes it difficult to manage the economy of the process. Further, these systems are much more susceptible to contamination with unwanted microalgae and fungi, bacteria and protozoa that feed on algae. Recently, some work has been done to improve lipid production from algal biomass by implementing in silico and in vitro biochemical, genetic and metabolic engineering approaches. This article represents a comprehensive discussion about the potential of microalgae for the production of valuable lipid compounds that can be further used for biodiesel production.
Current Status and Outlook in the Application of Microalgae in Biodiesel Production and Environmental Protection  [PDF]
Junfeng Rong,Hui Chen,Qiang Wang
Frontiers in Energy Research , 2014, DOI: 10.3389/fenrg.2014.00032
Abstract: Microalgae have been currently recognized as a group of the most potential feedstocks for biodiesel production due to high productivity potential, efficient biosynthesis of lipids, and less competition with food production. Moreover, utilization of microalgae with environmental purposes (CO2 fixation, NOx, and wastewater treatment) and biorefinery has been reported. However, there are still challenges that need to be addressed to ensure stable large-scale production with positive net energy balance. This review gives an overview of the current status of the application of microalgae in biodiesel production and environmental protection. The practical problems not only facing the microalgae biodiesel production but also associated with microalgae application for environmental pollution control, in particular biological fixation of greenhouse gas (CO2 and NOx) and wastewater treatment are described in detail. Notably, the synergistic combination of various applications (e.g., food, medicine, wastewater treatment, and flue gas treatment) with biodiesel production could enhance the sustainability and economics of the algal biodiesel production system.
Cultivation of Microalgae Monoraphidium sp., in the Plant Pilot the Grand Valle Bio Energy, for Biodiesel Production  [PDF]
Gisel Chenard Díaz, Yordanka Reyes Cruz, René González Carliz, Rosa C. Vitorino de Paula, Donato A. Gomes Aranda, Marcellus A. G. Dario, Gustavo Saraiva Marass, Nelson C. Furtado
Natural Science (NS) , 2015, DOI: 10.4236/ns.2015.77040
Abstract: At present, Brazil imports approximately 11 billion liters/year of diesel. With the interruption of the works in the new Petrobras refineries, the projection is that by 2025 this volume will increase to 24.2 billion liters of diesel/year. In this sense, the biodiesel factory Grand Valle Bio Energy Ltda., located in the state of Rio de Janeiro, in conjunction with the FAPERJ makes some investments in technology development for the cultivation and use of microalgae as an alternative raw material in the production of biodiesel. Based on arguments previously said, this work presents the results of the microalgae cultivation Monoraphidium sp. in photobioreactors the pilot plant of the company. The installation with an area of 120 m2 is included with 2 open photobioreactors of type falling film (20 m × 1 m), with a cascade of 18mm and capacity of 4000 L. The lineage cultivated is selected from previous ecophysiological studies that are identified as promising for biodiesel production by having a high potential for the production of lipids. This lineage is maintained at collection of the stock of cultures Laboratory of Green Technologies of the School of Chemistry/ UFRJ. The cultivation was performed in means ASM-1 (Gorham et al., 1964), initial pH 8.0, with aeration and circulation average of 8 hours a day during 19 days. The culture was started with an inoculum of 1 × 107 cel/ml. The lipid production was determined in two phases of growth: on day 4 (exponential phase) and 15 day (stationary phase). For the determination and quantification of lipid content, two different methods were assessed for a sample of biomass, submitted to the same processes the separation and drying. The results showed the methodology of Bligh & Dyer with modifications as the most efficient in extracting lipids. The total lipid content of the biomass Monoraphidium sp. was 30.58%. The growth rate varied between 0.74 ± 0.01 and 0.68 ± 0.02.
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