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Biodiesel renovável derivado de microalgas: avanços e perspectivas tecnológicas; Biodiesel derived from microalgae: advances and perspectives

Pereira, Claudio M. P.; Hobuss, Cristiane B.; Maciel, Juliana Villela; Ferreira, Lizângela R.; Del Pino, Francisco B.; Mesko, Márcia F.; Jacob-Lopes, Eduardo; Neto, Pio Colepicolo
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
37.31%
Microalgae are a promising source of raw material for biodiesel production. This review discusses the latest developments related to the application of microalgae biomass for biodiesel production. Characterization of fatty acid of microalgae and comparisons with other sources of raw materials and processes are presented. Furthermore, technological perspectives and approaches for growing microalgae in photobioreactors, microalgal oil extraction techniques, and procedures for synthesizing biodiesel are reviewed.

Produção de microalgas e caracterização de sua composição protêica e lipídica via espectrometria de massas.; Production of microalgae and characterization of their proteic and lipidic composition by mass spectrometry.

Andrade, Lidiane Maria de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 19/09/2014 PT
Relevância na Pesquisa
37.5%
As mudanças climáticas associadas às atividades humana são devidas principalmente às emissões de CO2 na atmosfera provenientes da queima de combustíveis de origem fóssil. Desta forma, faz-se necessária a substituição dessas fontes fósseis de geração de energia, por fontes renováveis. Dentre as alternativas de fontes renováveis, podemos destacar os biocombustíveis produzidos a partir de microalgas, as quais apresentam composição rica em óleos e proteínas. Um dos grandes desafios encontrados na conversão de biomassa em biocombustíveis é a caracterização detalhada das microalgas. A identificação de espécies através da espectrometria de massas com Ionização/Dessorção à Laser Assistida por Matriz acoplada a analisador por tempo de vôo (MALDI-TOF-MS) utilizada na análise de perfil de proteínas de micro-organismos, e posterior rápida identificação por comparação com os padrões armazenados em bancos de dados (fingerprint) tem se sobressaído. Existem poucos trabalhos na literatura abordando a identificação de espécies de microalgas utilizando a técnica de MALDI-TOF-MS e nenhum trabalho abordando a análise a partir do uso de células de microalgas liofilizadas. Desta forma, nesse trabalho foi estudada a influência de diversos parâmetros tais como placa...

Estudo de fontes de carbono orgânicos no cultivo heterotrófico da microalga Chlorella vulgaris; Studies the organic carbon sources for heterotrophic culture from microalgae Chlorella vulgaris

Liliana Marcela Franco Acosta
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 18/12/2012 PT
Relevância na Pesquisa
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Em cultivos heterotróficos, fontes orgânicas de carbono são utilizadas para fornecer energia e carbono ao micro-organismo. A glicose e uma das fontes mais utilizadas em cultivos de microalgas, gerando elevadas taxas de crescimento. Outras fontes como frutose, xilose, glicerol, sacarose, arabinose também podem ser utilizadas e a escolha entre essas fontes orgânicas e função principalmente das taxas de crescimento e do custo de aquisição. Visando elevadas produtividades e a redução do custo do cultivo heterotrófico da Chlorella vulgaris, diferentes fontes de carbono orgânico foram avaliadas (glicerol, sacarose, frutose e melaço de cana). Os máximos valores de concentração celular, pH e produtividade, foram para a sacarose hidrolisada na concentração inicial de 20 g.L-1 obtidos apos 122 horas de cultivo (5,3g.L-1; 8.80 e 0.040 g.L-1.h-1, respectivamente) e para o melaço de cana hidrolisado na concentração de 30 g.L-1 obtidos apos 60 horas de cultivo (3,92 g.L-1; 8,55 e 0,059 g.L-1.h-1, respectivamente). Glicerol, sacarose e frutose não foram consumidas pelas células. As melhores concentrações de sacarose hidrolisada (20 g.L-1) e melaço de cana hidrolisado (15 g.L-1) foram utilizados em fermentador de 3 L em regime de batelada alimentada...

Cultivo de microalgas para produção de bioetanol de terceira geração; Microalgae cultivation for third generation bioethanol production

Bruno Colling Klein
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/02/2013 PT
Relevância na Pesquisa
37.31%
A busca por uma maior sustentabilidade tem levado a uma mudança em direção à utilização de fontes renováveis para geração de energia em detrimento do uso de combustíveis fósseis, visando a uma modificação na matriz energética global. A utilização da biomassa de microalgas para produção de biocombustíveis vem sendo vista como uma alternativa promissora, uma vez que o seu cultivo proporciona produtividades em carboidratos e lipídios superiores às matérias-primas vegetais convencionalmente utilizadas na obtenção de etanol e biodiesel. Neste contexto, o objetivo da presente dissertação de mestrado foi avaliar a produção de biomassa da microalga clorofícea Chlorella vulgaris em fotobiorreator de placa plana em diferentes condições de fluxo luminoso, concentração de CO2 na alimentação gasosa e concentração de NaNO3 no meio de cultivo, visando o acúmulo de carboidratos para obtenção de bioetanol de terceira geração. As influências das variáveis nutricionais e de processo sobre a eficiência fotossintética das microalgas também foram estimadas para determinação do estado fisiológico das culturas. A produtividade média de biomassa e a concentração máxima final das microalgas foram significativamente afetadas pela incidência de radiação luminosa e pela suplementação de CO2 gasoso...

Ésteres etílicos de microalga : equilíbrio e propriedades físicas; Ethyl esters of microalgae : equilibrium and physical properties

Karolynne Weber Lucchesi
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/03/2015 PT
Relevância na Pesquisa
37.45%
A biomassa de microalgas vem despertando grande interesse científico como matéria prima para produção de biodiesel, devido ao elevado teor de óleo de algumas espécies, além de ser uma importante fonte para a produção de diversos biocompostos. Seu cultivo não compete com a produção de alimentos e ainda auxilia na captura de CO2, tendo um impacto benéfico para o meio ambiente. Diante desta promissora potencialidade, este trabalho objetiva investigar a produção de ésteres etílicos a partir de óleo de microalgas, avaliando as propriedades físicas destes ésteres e do óleo, além de estudar o equilíbrio líquido-líquido de algumas misturas de interesse. Óleo comercial de microalga da espécie Chlorella protothecoides, obtido junto à empresa Solebyo, foi utilizado como matéria prima para a produção do biodiesel (etanol como álcool reagente), obtendo-se um biocombustível totalmente renovável. O óleo foi caracterizado em termos dos seus ácidos graxos, estimando-se sua composição em triacilgliceróis (TAG). A dependência da viscosidade e densidade com relação à temperatura, índice de acidez e teor de umidade, foram determinados para o óleo e seu respectivo biodiesel. Uma análise adicional de ponto de fulgor foi realizada exclusivamente para o biodiesel. Por fim...

Biodiesel production by microalgae and macroalgae from north littoral portuguese coast

Carvalho, Joana; Ribeiro, André; Castro, Joana Daniela Fernandes; Vilarinho, Cândida; Castro, F.
Fonte: CVR - Centro para a Valorização de Resíduos Publicador: CVR - Centro para a Valorização de Resíduos
Tipo: Conferência ou Objeto de Conferência
Publicado em /10/2011 ENG
Relevância na Pesquisa
37.31%
Biodiesel, as an alternative fuel, has many benefits. It is biodegradable, non-toxic and compared to petroleum-based diesel, has a more favorable combustion emission profile, such as low emissions of carbon monoxide, particulate matter and unburned hydrocarbons. In brief, these merits make biodiesel a good alternative to petroleum based fuel. Biodiesel feedstocks derived from microalgae and macroalgae have emerged as one of the most promising alternative sources of lipid for use in biodiesel production because of their high photosynthetic efficiency to produce biomass and their higher growth rates and productivity compared to conventional crops. In addition to their fast reproduction, they are easier to cultivate than many other types of plants and can produce a higher yield of oil for biodiesel production. In this work biodiesel was produced using the species of microalgae Chlorella emersonii and Botrycoccus braunii due to its high oil content. Biodiesel productions through macroalgae oil are in preliminary phase. Therefore, results and methodology will not be presented in this work. Technological assessment of process was carried out to evaluate their technical benefits, limitations and quality of final product. In this work biodiesel from microalgae oil was produced by an alkali-catalyzed transesterification and it was achieved 93% of mass conversion. The evaluation of quality from raw materials and final biodiesel was performed according to standard EN 14214. Results show that all parameters analyzed meet the standard and legislation requirements. This evidence proves that in those operational conditions the biodiesel produced from microalgae can substitute petroleum-based diesel.

Development and optimization of microalgae cultivation systems : microalgal composition, photobioreactor design and characterization

Fernandes, Bruno Daniel
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Tese de Doutorado
Publicado em 18/06/2013 ENG
Relevância na Pesquisa
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Tese de doutoramento em Biological and Chemical Engineering; This work aimed at the development and optimization of systems and techniques for microalgae cultivation, in order to make the process economically and environmentally sustainable. Three different strategies were adopted: i) maximize productivity through the optimization of culture conditions, ii) maximize productivity and decrease costs by the use of agro-industrial waste as cultivation medium; iii) development of a new, low cost and highly productive microalgae cultivation system. Carbon dioxide (CO2) is the most widely used carbon source for photoautotrophic growth of microalgae. The rate of CO2 fixation (RCO2) by Chlorella vulgaris was maximized by defining the values of CO2 concentration in air feed and aeration rate. The results revealed that the maximum RCO2 (2.22 g L-1 d-1) was obtained using 6.5% (v/v) CO2 and 0.5 vvm. Although biomass concentration and mass productivity were affected by growth conditions, no differences were obtained in the biochemical composition of cells. The optimization of specific productivity (starch and lipids for the production of bioethanol and biodiesel, respectively) was performed using strategies of nutrient limitation. Starch accumulation in C. vulgaris cells was evaluated under different initial concentrations of urea (nitrogen source) and FeNa-EDTA (iron source) in the medium. Based on the results...

Biodiesel from microalgae Chlorella protothecoides growing at autotrophic and heterotrophic metabolisms in a new symbiotic bioreactor

Santos, Carla A.; Reis, Alberto
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em //2013 ENG
Relevância na Pesquisa
37.54%
Biodiesel is an alternative energy to fossil fuels, and is produced from biomass, therefore provides lower CO2 emissions. Currently, biodiesel is produced from plant oils, animal fats and used oils. These sources are low-yield which is a limitation to the production of biodiesel in large quantities. On the contrary, microalgae present a very high yield and can be produced in large amounts. The bio-refinery of microalgae oil must have a strategy of taking advantage of all by-products to make the whole process economic feasible. The bio-refinery proposed on this work is based on a first step to produce microalgae in a symbiotic bioreactor. The symbiotic bioreactor consists of an association of a fermenter and a photobioreactor connected by the gas phase on closed circuit. Two sorts of microalgae biomass are obtained: the heterotrophic microalgae from the fermenter and the autotrophic microalgae from the VAP (vertical alveolar panel photobioreactor). The best strategy is to use the heterotrophic microalgae to extract the oil as it has a higher content in lipids, and, then to produce biodiesel; additionally carotenoids as lutein can be extracted along with lipids from the heterotrophic microalga as a High Value Product (HVP). On the other hand...

Microalgae population dynamics in photobioreactors with secondary sewage effluent as culture medium

Marchello,Adriano E.; Lombardi,Ana T.; Dellamano-Oliveira,Maria José; Souza,Clovis W.O. de
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2015 EN
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37.45%
Nitrogen and phosphorus present in sewage can be used for microalgae growth, possibiliting cost reduction in the production of microalgae at the same time that it decreases the eutrophication potential of the effluent. This research aimed at monitoring the native community of microalgae and coliform bacteria in a secondary effluent from anaerobic municipal sewage treatment. Two treatments (aerated and non-aerated) were performed to grow microalgae under semi-controlled conditions in semi-closed photobioreactors in a greenhouse. The results showed no significant pH and coliforms (total and Escherichia coli) variation between treatments. Nutrient concentrations were reduced supporting microalgae growth up to 107 cells.mL−1 independent of aeration. Exponential growth was obtained from the first day for the non-aerated, but a 5 day lag phase of growth was obtained for the aerated. Chlorella vulgaris was the dominant microalgae (99.9%) in both treatments. In the aerated, 5 algae classes were detected (Chlorophyceae, Cyanophyceae, Chrysophyceae, Bacillariophyceae and Euglenophyceae), with 12 taxa, whereas in the non-aerated, 2 classes were identified (Chlorophyceae and Cyanophyceae), with 5 taxa. We concluded that effluent is viable for microalgae growth...

An evaluation of the accumulation of intracellular inorganic nitrogen pools by marine microalgae in batch cultures

Lavín,Paris L.; Lourenço,Sergio O.
Fonte: Universidade de São Paulo, Instituto Oceanográfico Publicador: Universidade de São Paulo, Instituto Oceanográfico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2005 EN
Relevância na Pesquisa
37.31%
Methods of extraction, changes in concentrations with growth, and effects of culture conditions on intracellular inorganic nitrogen pools (IIN - ammonia, nitrite, and nitrate) were studied in nine species of marine microalgae in batch cultures. The microalgae were analysed to compare three methods of extraction of IIN, one of them developed in this study. The extraction of IIN occurs efficient by with all three methods for four out of the nine species tested. However, for five species significant differences were found among the methods, the best results being obtained with the new method. Microalgae accumulate inorganic forms of nitrogen in different proportions. The species show higher concentrations of either ammonia or nitrate, and always lower concentrations of nitrite. Microalgae of smaller cellular volumes tend to attain higher values of IIN per cubic micrometer (the converse in large-volume species), with some exceptions (Amphidinium carterae and Nannochloropsis oculata). The use of aeration in the cultures determines a decrease in the concentrations of IIN, favours nitrogen assimilation, and generates an increase in growth rates and C:N ratio. High concentrations of IIN are characteristic of the exponential growth phase, but in some cases their occurrence may result from carbon deficiency.

The role of biochemical engineering in the production of biofuels from microalgae

Costa, Jorge Alberto Vieira; Morais, Michele Greque de
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.37%
Environmental changes that have occurred due to the use of fossil fuels have driven the search for alternative sources that have a lower environmental impact. First-generation biofuels were derived from crops such as sugar cane, corn and soybean, which contribute to water scarcity and deforestation. Second-generation biofuels originated from lignocellulose agriculture and forest residues, however these needed large areas of land that could be used for food production. Based on technology projections, the third generation of biofuels will be derived from microalgae. Microalgae are considered to be an alternative energy source without the drawbacks of the first- and second-generation biofuels. Depending upon the growing conditions, microalgae can produce biocompounds that are easily converted into biofuels. The biofuels from microalgae are an alternative that can keep the development of human activity in harmony with the environment. This study aimed to present the main biofuels that can be derived from microalgae.

Avaliação da produção de biodiesel de microalga Isochrysis galbana via transesterificação in situ; Evaluation of biodiesel production from microalgae Isochrysis galbana via in situ transesterification

Procópio, Zaniel Souto Dantas
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Química; Pesquisa e Desenvolvimento de Tecnologias Regionais Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Química; Pesquisa e Desenvolvimento de Tecnologias Regionais
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.48%
Microalgae are microscopic photosynthetic organisms that grow rapidly and in different environmental conditions due to their simple cellular structure. The cultivation of microalgae is a biological system capable of storing solar energy through the production of organic compounds via photosynthesis, and these species presents growth faster than land plants, enabling higher biomass yield. Thus, it is understood that the cultivation of these photosynthetic mechanisms is part of a relevant proposal, since, when compared to other oil producing raw materials, they have a significantly higher productivity, thus being a raw material able to complete the current demand by biodiesel . The overall aim of the thesis was to obtain biofuel via transesterification process of bio oil from the microalgae Isochrysis galbana. The specific objective was to estimate the use of a photobioreactor at the laboratory level, for the experiments of microalgae growth; evaluating the characteristics of biodiesel from microalgae produced by in situ transesterification process; studying a new route for disinfection of microalgae cultivation, through the use of the chemical agent sodium hypochlorite. The introduction of this new method allowed obtaining the kinetics of the photobioreactor for cultivation...

Análise de elementos químicos em microalgas dulcícolas avaliadas como matéria-prima para produção de biodiesel e seus coprodutos; Analysis of chemical elements in freshwater microalgae evaluated as a feedstock for biodiesel production and its byproducts

Wendt, Eliéser Viégas
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Química (IQ); Instituto de Química - IQ (RG) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Química (IQ); Instituto de Química - IQ (RG)
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.45%
The purpose of this study was to determine the composition of chemical elements in freshwater microalgae evaluated as feedstock for biodiesel production in order to assess possible consequences on the biodiesel quality and to determine whether the use of residual biomass as animal feed. So the 26 chemicals elements in 76 freshwater algae samples, 39 microalgae biomass obtained once direct transesterification, 6 oilseeds, one sample of beef tallow as well as biomass, oil and biodiesel of microalgae Desmodesmus ssp. were measured by ICP-OES. Microalgae stood out compared to conventional feedstock due to higher contents of Na and Fe, moreover chemical elements such as Al, B, Cu, Mn, Sn, Zn and as Fe, are not monitored and may be existing in microalgae biodiesel. Thru direct transesterification procedure, most of the macronutrients constituents of microalgae is lost. Residual biomass by solvent extraction process keeps the mineral composition and in this case, is the most suitable for animal feed. The contents of chemical elements from Desmodesmus ssp. biomass decrease throughout the biodiesel production process by direct transesterification. However, the P content in biofuel was 127 mg/kg, about 13 times beyond the specification...

Culturing and harvesting marine microalgae for the large-scale production of biodiesel.

Sathe, Suraj
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2010
Relevância na Pesquisa
37.56%
In the commercial production of biodiesel from marine microalgae, the cost and efficiency of harvesting technique affects the overall cost and production of biodiesel. The commercial harvesting techniques being used for harvesting microalgae include centrifugation and filtration preceded by flocculation. Centrifugation and filtration are very high cost processes and different flocculation techniques like chemical flocculation, auto-flocculation and bio-flocculation (microbial flocculation) are being developed to achieve more efficiency in flocculation of algal biomass at lower costs. In this project, ‘Electroflocculation’- a common process for flocculating contaminants, organic matter and metal ions from waste water was applied to flocculate marine microalgae. The studies presented in the thesis aim to 1. determine the effect of electroflocculation on the flocculation of marine microalgae at lab scale 2. investigate the factors affecting electroflocculation i.e. current density, time, material of electrodes, distance between electrodes, salinity of the cultures and pH 3. scale-up the lab scale electroflocculation process to pilot-scale and investigate the cost effectiveness of pilot-scale electroflocculation process 4. theoretically optimize...

Downstream processing of marine microalgae for the commercial scale production of biofuels.

Lee, Andrew Kwong
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2013
Relevância na Pesquisa
37.37%
Several species of microalgae have lipid yields that are about 4 to 5 times of that from the highest oil bearing terrestrial plants such as oil palm. Furthermore, marine species can offer the additional advantage of not competing with farm produce for fresh water or arable land. These advantages make marine microalgae appear to be attractive as a feedstock for the production of biofuels; however, despite intensive research, the production cost of microalgal biomass remains high at about A$ 10 kg⁻¹. In comparison, plantation oil such as canola can be available of about $1 L⁻¹ and this large cost difference makes algal biofuels uncompetitive. Hence, the sustainability of microalgal biofuel production depends very much on the technical, energetic and economic issues involved with production. Microalgal lipids and carbohydrates are major feedstock for renewable fuels and the downstream processing can broadly be classified into four steps: harvesting, dewatering, cell disruption and extraction of the desirable products. The specific objectives for the PhD study were harvesting and cell disruption of microalgae; these objectives were structured towards the development of pilot scale production of marine microalgae and included technical...

Anaerobic Digestibility of Microalgae : Fate and Limitations of Long Chain Fatty Acids in the Biodegradation of Lipids

Hamani Abdou, Rekia
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
EN
Relevância na Pesquisa
37.41%
La digestion anaérobie est un processus biologique dans lequel un consortium microbien complexe fonctionnant en absence d’oxygène transforme la matière organique en biogaz, principalement en méthane et en dioxyde de carbone. Parmi les substrats organiques, les lipides sont les plus productifs de méthane par rapport aux glucides et aux protéines; mais leur dégradation est très difficile, en raison de leur hydrolyse qui peut être l’étape limitante. Les algues peuvent être une source importante pour la production de méthane à cause de leur contenu en lipides potentiellement élevé. L’objectif de cette étude était, par conséquent, d’évaluer la production en méthane des microalgues en utilisant la technique du BMP (Biochemical méthane Potential) et d’identifier les limites de biodégradion des lipides dans la digestion anaérobie. Le plan expérimental a été divisé en plusieurs étapes: 1) Comparer le potentiel énergétique en méthane des macroalgues par rapport aux microalgues. 2) Faire le criblage de différentes espèces de microalgues d’eau douce et marines afin de comparer leur potentiel en méthane. 3) Déterminer l'impact des prétraitements sur la production de méthane de quelques microalgues ciblées. 4) Identifier les limites de biodégradation des lipides algaux dans la digestion anaérobie...

Análise de elementos químicos em microalgas marinhas; Analysis of chemical elements in marine microalgae

Silva, Bruna Ferreira
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Química (IQ); Instituto de Química - IQ (RG) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Química (IQ); Instituto de Química - IQ (RG)
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.37%
This study was divided in two chapters. The first one focused the quantification of 26 chemical elements by ICP OES in 56 marine microalgae samples, which are potential raw material for biodiesel production. The results showed that most of these biomasses have more than 18% dry mass of these elements, when added, being much superior to freshwater microalgae and oilseeds already used in the process. These high contents were determined by Na, followed by, Mg, K and Ca, which are natural seawater constituents. It was possible to observe biosorption patterns of some chemical elements by the use of chemmometrics analysis. Among analyzed strains, P. tricornutum cultivated in f/2 media, washed with ammonium formiate and dried in incubator at 60ºC, seems to be the most promising to biodiesel destination. However, in order to get the main purpose of this study, elements profiles presented by microalgae aren't favorable, since small amounts of these elements are allowed in biodiesel because they are responsible for its oxidation and reaction with engine parts. Thus, in the second chapter it was evaluated biomass washing with water, in order to approach their compositions to conventional oilseeds. This step presents considerable removal of these elements by using 43 mL water to 1 g biomass...

Design and Development of a Solar Dryer for Microalgae Retrieval - An EPS@ISEP 2013 Spring Project

Brygider, Aleksandra; Marciniak, Bartlomiej; Verbraeken, Bénédicte; Ahlskog, Paul; Petersen, Sven; Malheiro, Benedita; Ribeiro, Maria Cristina; Silva, Manuel; Caetano, Nídia Sá; Ferreira, Paulo; Guedes, Pedro
Fonte: ACM Publicador: ACM
Tipo: Artigo de Revista Científica
Publicado em //2015 N/A
Relevância na Pesquisa
37.54%
Currently excessive fossil fuel consumption has become a serious problem. People are searching for new solutions of energy production and there are several options to obtain alternative sources of energy without further devastating the already destroyed environment. One of these solutions is growing microalgae, from which biodiesel can be obtained. The microalgae production is a growing business because of its many useful compounds. In order to collect these compounds microalgae must first be harvested and then dried. Nowadays the solutions used for drying use too much energy and therefore are too expensive and not sustainable. The goal of this project, one of the possible choices during the EPS@ISEP 2013 Spring, was to develop a solar microalgae dryer. The multinational team involved in its development was composed of five students, from distinct countries and fields of study, and was the responsible for designing a solar microalgae dryer prototype for the microalgae laboratory of the chemical engineering department at ISEP, suitable for future tests and incorporating control process (in order not to destroy the microalgae during the drying process). The solar microalgae dryer was built to work as a distiller that gets rid of the excess water from the microalgae suspension. This paper presents a possible solution for this problem...

Direct conversion of microalgae biomass to biocrude with hydrothermal liquefaction.

Eboibi, Blessing Elo-oghene
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2015
Relevância na Pesquisa
37.62%
Microalgae are generally considered as a promising biomass source for applications including production of advanced biofuels, chemicals, wastewater treatments, various organic substances or a combination of any of the above. The advantages of microalgae includes faster growth rates than terrestrial plants, ability to use non-arable land for mass production, and their ability to grow in poor quality water, as well as their ability to remove pollutants from wastewater streams. However, one of the major challenges of microalgae for commercialisation to is its economic downstream production and conversion to biofuels and chemicals. When harvested, microalgae contains up to ~90% water content, thus economic conversion of high moisture content biomass to valuable products such as biofuels remains a challenge. Hydrothermal liquefaction (HTL) involves processing of high moisture content biomass in hot compressed water, avoiding the drying step for biomass feedstocks. Therefore HTL is advantageous as it avoids the energy intensive drying process in contrast to processes that involve drying of biomass prior to processing into biofuels. HTL products comprise biocrude, solid residues, aqueous and gas phases. The primary product biocrude is upgradable to liquid transportation fuels. The aqueous phase contains essential nutrients that could be recycled to microalgae cultivation ponds. The gas phase contains about 98mol% carbon dioxide (CO₂) and 2mol% hydrocarbon gases. The gas phase can also be directly recycled to the microalgae cultivation ponds for pH control and supply of CO₂...

Análise da Viabilidade Econômica da Energia Elétrica Gerada através das Microalgas; ANALYSIS OF THE ECONOMIC FEASIBILITY OF ELECTRICITY GENERATED BY FROM MICROALGAE; ANALYSIS OF THE ECONOMIC FEASIBILITY OF ELECTRICITY GENERATED BY FROM MICROALGAE

Holanda, Laryssa Ramos; UFPE; Ramos, Francisco de Sousa; UFPE
Fonte: Universidade Federal Fluminense - LATEC Publicador: Universidade Federal Fluminense - LATEC
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; Estudo de caso; Prototipagem. Formato: application/pdf
Publicado em 30/05/2012 POR
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Este artigo analisa a viabilidade econômica de um processo de produção de microalgas para geração de eletricidade, considerado como uma atividade conjunta com o etanol, de modo a suprir a elevação da demanda prevista de energia ocasionada pelo crescimento econômico do país. A produção dessa fonte de energia alternativa em conjunto com uma usina de etanol maximiza os ganhos de ambas, além de trazer benefícios ao meio ambiente, com as microalgas captando o dióxido de carbono emitido pela usina de etanol. Através de estimativas de custo e produção, uma análise de investimento do projeto de produção de energia a partir de microalgas é feita de acordo com os critérios do valor presente líquido, da taxa interna de retorno e da razão benefício/custo. O resultado obtido com a aplicação dos três critérios é a confirmação da viabilidade econômica do processo produtivo de microalgas para geração de bioeletricidade no Brasil.; This study examines the economic viability of a production process of microalgae to generateelectricity, considered as a joint activity with ethanol in order to meet rising demand provided energy caused by thecountry’s economic growth. The production of this alternative energy source in conjunction with an ethanolplant maximizes the gains of both...