AGDAA. Artículos de Investigación
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Examinando AGDAA. Artículos de Investigación por Autor "Barajas Solano, Andrés Fernando"
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- PublicaciónAcceso abiertoDesign of an electroflotation system for the concentration and harvesting of freshwater microalgae(2018) Castellanos Estupiñan, Miguel A.; Sánchez Galvis, Edwar M.; García Martínez, Janet Bibiana; Barajas Ferreira, Crisóstomo; Zuorro, Antonio; Barajas Solano, Andrés FernandoMicroalgae are considered as one of the most promising alternatives for the integrated use of agro-industrial water residues and the production of metabolites of high industrial interest. This is due to algae can grow on wastewater which in turn can reduce the emission of nutrients to rivers and lakes. However, the greatest scientific-technological barrier is the concentration and separation of the biomass produced. There are several processes used at different levels (from laboratory to industrial scale) such as flocculation, centrifugation, flotation, etc. These can be very expensive or can (possibly) contaminate the biomass. Unlike the previous ones, electroflotation has been proposed as a cost-efficient method, nevertheless its final efficiency will depend heavily on the type of alga and culture medium. Taking into account the above, the present project aims to design an electroflotation system for the concentration and harvest of microalgae biomass. The effect of several factors (pH, time, voltage and distance between the electrodes) and for types of materials (Copper, Aluminium, Iron and Steel) on biomass recovery efficiency from a culture of Chlorella vulgaris UTEX 1803 was evaluated by the implementation of a Design of experiments (43 non-factorial design) using STATISTICA 7.0. Results show that, the materials with higher concentration efficiency were cooper and aluminium with 40 and 80% respectively, and the most relevant factors were distance between electrodes (1-2 cm), time (>20 min) and Voltage (>15V). In order to increase the efficiency of the overall process a new 43 experimental factorial design was proposed using as factors distance between electrodes, time, voltage and agitation. Results show that agitation positively affects the total efficiency until reaching a total concentration of the biomass (100%). It was found that a voltage close to 50V and a time greater than 25 min positively affect the final efficiency of the copper and aluminium electrodes, however aluminium has the highest efficiency (> 95%) compared to copper (<85%).
- PublicaciónAcceso abiertoEffect of carbon-nitrogen ratio for the biomass production, hydrocarbons and lipids on botryoccus braunii UIS 003.(2016-04) Barajas Solano, Andrés Fernando; Guzmán Monsalve, Alexander; Kafarov, ViatcheslavThe genus Botryococcus compiles a variety of green microalgae which accumulate large quantities of hydrocarbons, this genus is classified in four types or races (A, B, L and R) based on chemical structure of hydrocarbons. Race B has been acknowledge due to its hability to accumulate triterpene hydrocarbons C30- C37 best known as botriococene and methylated squalene C31-C34 which are considerate as candidates for biofuels production; however, one of the main problems that face biofuels production using this alga as feedstock is the continuous production, both lipids and hydrocarbons; that is why it’s mandatory to find the best carbon and nitrogen source that maximizes biomass and total lipid production. It was found that by adjusting the carbon/nitrogen ratio using sodium carbonate (Na2CO3) it was possible to substantially improve the production of biomass from 1 to 2 g/L in 15 days thus doubling the production of biomass in the same time; however, both the lipids and hydrocarbons production will not be affected positively showing a significant reduction from baseline.
- PublicaciónAcceso abiertoEvaluation of a two-phase extraction system of carbohydrates and proteins from chlorella vulgaris utex 1803(2016-04) García Martínez, Janet Bibiana; Ayala Torres, Edinson; Reyes Gómez, Oscar; Zuorro, Antonio; Barajas Solano, Andrés Fernando; Barajas Ferreira, CrisóstomoMicroalgae are a valuable source of high-value products and biofuels, however the high-energy cost required for the extraction of their metabolites has kept questioning on possible industrial upgrading. The aim of this study was to evaluate the effect of temperature, solvent/biomass, NaOH concentration and thermal pretreatment of the biomass in a 2-cycle carbohydrate and protein extraction system. Results shown that best conditions for carbohydrates extraction are achieved at a solvent concentration of 3.67 M, 55°C and a solvent/biomass ratio of 30mL/g. On the other side, the best conditions for protein were 3 M, 85°C and 45 mL/g. The efficiencies achieved under these conditions were 95% for carbohydrates and 98% for proteins. Using the best extraction conditions for each metabolite a thermal pre-treatment was performed at 25°C, 75°C and 105ºC. Results indicate that highest efficiencies were achieved with dry biomass pretreated at 105°C, with values of 95% for carbohydrates and 98% for proteins.
- PublicaciónAcceso abiertoEvaluation of the efficiency of bio-polymers derived from desertic plants as flocculation agents(2016-05-20) Daza, Rina; Barajas Solano, Andrés Fernando; Epalza Contreras, Jesús-ManuelIn the treatment of wastewater, flocculation is one of the most used processes, which aims to eliminate colloidal particles cannot be removed by other methods; Traditionally it has been used aluminum or iron salts and synthetic polymer, which generate little biodegradable sludge; moreover biopolymers, have coagulation and flocculation properties which can remove over 80-90% of solids contaminated; additionally, the use of natural polymers produce sludge increased biodegradability. The present work analyzes the efficiency of a biopolimer based on 6 endemic plants (Opuntia dilleni, Stenocereus griseus, Cereus forbesii, Melocactus sp. Aloe arborescens and Aloe vera) found at the desertic indian reservation “Kululumana”.
- PublicaciónAcceso abiertoHidrodestilación asistida con microondas (MWHD) para la extracción de hidrolatos de plantas aromáticas(2015-07) Guarín Villamizar, Oscar Darío; Barajas Solano, Andrés FernandoEn este estudio, se evalúa la eficiencia de extracción de un sistema de hidrodestilación asistida por microondas para la obtención de hidrolatos a partir de tres plantas aromáticas (Eucalyptus Globulus, Mentha Viridis y Cymbopogon Citratus). Los resultados obtenidos demuestran que, para obtener una mayor cantidad de hidrolato (yerbabuena del 42, limonaria 36 y ecualipto 33%), es necesario emplear tiempos de extracción cercanos a los 45 minutos y concentraciones de biomasa de 160 g; Además, a partir del balance de energía se obtiene que, para obtener 0,98 g de hidrolato son necesarios 1158,952 KJ; por otra parte, teniendo en cuenta los resultados obtenidos, es posible determinar que, el impacto generado al medio ambiente por la operación unitaria empleada es alto; teniendo en cuenta el gasto de 1,650 kWh se tiene una huella de carbono de entre 1320-220 g de CO2.
- PublicaciónAcceso abiertoImprovement of biomass and dha production on a semi-continuous culture of aurantiochytrium sp NYH-2(2016-04) Barajas Solano, Andrés Fernando; Yoshida, Masaki; Watanabe, Makoto MAurantiochytrium sp has been recognized as one of the most suitable sources of high valuable fatty acids (FA) including docosahexaenoic acid (DHA), docosapentaenoic acid, arachidonic acid, eicosapentaenoic acid (EPA), and saturated FA; however it’s necessary to improve total biomass production and high value FA specially DHA. The aim of this research is to improve the production of biomass and DHA on the novel Aurantiochytrium sp NYH-2 strain via an optimization of culture time (2, 3 and 5 days) and removal of culture (20, 50 and 80% v/v) using a 23 experimental design. It was found that in order to improve biomass production a large amount of culture media must be replaced (>90%), however after the third cycle biomass production was reduced from 10 g/L to 9 g/L; similarly under the same conditions lipids and DHA production increased from 15% to 20% (w/w) and from 3 to 5% (w/w) respectively in the first 3 cycles and then reduced in cycle 5. Finally results suggest that in a semi-continuous process the algae is only functional 3 cycles (9 to 12 days) and in order to improve total biomass lipids and DHA production, a volume of culture media between 80-92% must be removed every 3-4 days.
- PublicaciónAcceso abiertoMicroalgae immobilization using hydrogels for environmental applications : Study of transient photopolymerization(2016-05-20) González-Delgado, Ángel Darío; Barajas Solano, Andrés Fernando; Peralta Ruiz, Yeimmy YolimaImmobilization of microalgae has emerged as a useful technique for effective environmental applications as removal of undesirable compounds from water, culture collection handling for CO2 capture, development of biosensors, and production of clean energy among others. In this work, polymerization of hydrogels is evaluated in order to generate adequate nanoporous morphology for microalgae immobilization via use of transient light intensity. Hydrogels were polymerized using a UV light intensity range between 140 and 700 mW/cm2 during 0.8 h and characterized using rheology evaluation using an angular frequency of 1 rad/s for defined monomer, initiator and solvent amounts. Results shows that transient light polymerization has a significant effect on average pore size and pore size distribution, obtaining different gel points between 1,300 and 1,700 s and modules between 4,000 and 13,000 Pa, allowing to adjust nanoporous morphology of hydrogels improving the attach viability of species of microalgae with variable sizes and shapes, and allowing to develop better hydrogels for novel microalgae immobilization-based applications.
- PublicaciónAcceso abiertoPassive microalgae immobilization for wastewater treatment : Study of residual glycerol consumption(2016-05-20) Blanco Suarez, Vanessa E.; Villamizar Sanchez, Susan S.; Peralta Ruiz, Yeimmy Yolima; González-Delgado, Ángel Darío; Barajas Solano, Andrés Fernando; Ardila Álvarez, Ana MaríaThe aim of the present study is to evaluate the viability of glycerol as carbon source on immobilized algae cultures coupled with a modification on nitrogen (NO3-) and phosphate (PO4) concentration for the production of high valuable compounds (carbohydrates, proteins and lipids). it was determined that the conditions who favour the deposition of carbohydrates are 3-5% (v/v) of glycerol and 0.37 (g/L) of NaNO3. On The other hand, for obtain higher amounts of lipids, a 3% (v/v) of glycerol coupled with a limitation in the nitrogen source (0.04 g/L) are needed. Finally, in order to improve deposition of total proteins, larger concentrations of glycerol (5% v/v), NaNO3 (>0.37 g/L) and phosphate are needed.
- PublicaciónAcceso abiertoProducción de biomasa y proteínas de Chlorella vulgaris Beyerinck (Chlorellales: Chlorellaceae) a través del diseño de medios de cultivo selectivos(2017-09) Barajas Solano, Andrés Fernando; Ardila Álvarez, Ana María; González Delgado, Ángel DaríoEn los últimos años se ha vuelto cada vez más frecuente el uso de medios de cultivo basados en fuentes de fósforo, nitrógeno y microelementos como alternativa a los medios tradicionales. Por lo tanto, en este trabajo se diseñaron dos medios de cultivo mixotróficos con diferentes concentraciones de nitrato de sodio, fosfato de potasio, acetato de sodio y carbonato de amonio (estos últimos como fuente de carbono), a fin de evaluar la producción de biomasa y proteínas a partir de la microalga Chlorella vulgaris. Se realizaron diagramas de Pareto y superficies de respuesta a fin de conocer la influencia de las variables de estudio sobre la producción de proteínas. Los resultados mostraron que las mayores producciones de biomasa (3,72 para el cultivo con acetato y 2,17 g/L para el cultivo con carbonato) están directamente relacionadas con el nitrato de sodio (1,96 mM) y el fosfato de potasio (2,11 mM). Además, los máximos porcentajes de proteínas obtenidos fueron 60% y 34% para los cultivos con acetato y carbonato, respectivamente, ambos con 2,94 mM de nitrato de sodio. Finalmente, con base en el diagrama de Pareto obtenido, se encontró que para el medio de cultivo con acetato no existieron variables significativas que influyeran sobre la producción de proteínas, mientras que, en el medio de cultivo con carbonato, el nitrato de sodio y el fosfato de potasio influyeron significativamente en la producción de este metabolito.
- PublicaciónAcceso abiertoProduction of chlorella vulgaris biomass on uv-treated wastewater as an alternative for environmental sustainability on high-mountain fisheries(2018) Guiza Franco, Luisa; Orozco Rojas, Luis G.; Sánchez Galvis, Edwar M.; García Martínez, Janet Bibiana; Barajas Ferreira, Crisóstomo; Zuorro, Antonio; Barajas Solano, Andrés FernandoThe sustained expansion of agricultural industry in Colombian high-mountain has led to an increased size of residues, especially untreated wastewater. This untreated water is an urgent matter for public and environmental health, not only by its nutrient concentration (composed especially of food residuals and feces) but also the presence of pathogens (virus, bacteria, etc.) which are discharged to the environment. The overall objective of this work is to evaluate the effect of UV-treated wastewater from a high-mountain fishery as culture media for the production of Chlorella vulgaris as a sustainable method for nutrient and water recirculation on the fishery production system. The UV-canal efficiency was evaluated by the implementation of an experimental factorial design (time, distance of the UV-lamps towards the canal, number of UV-lamps and the sample concentration) using STATISTICA 7.0 software. Results shown that time (3 to 5 minutes) and the number of lamps (3-4) of 15 Watts eliminate completely coliforms from the samples. After UV-treatment the resulting water was test as culture media for C. vulgaris production by the adjustment of C/N ratio (Sodium Carbonate/potassium nitrate) by the implementation of an experimental 23 factorial design. Results shown that higher nitrate concentrations (>0,22 g/L) and moderate carbonate concentrations (1 g/L) increase the final biomass concentration up to 4g/L in 20 days.