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Lemon oil is widely used in food manufacturing, however its tendency to oxidize and its lipophilic character requires its encapsulation, either in emulsions or in microcapsules. Conventional emulsification technologies are highly energy intensive, damaging shear and heat sensitive products. This work assesses a high-throughput low-energy premix emulsification system based on nickel micro-sieves to produce food grade lemon oil-water emulsions. Successful encapsulation is achieved when both the lemon oil fraction is about 5% and the ratio between the size of the coarse emulsion and the hydraulic diameter of the micro-sieves (dratio) is 1 or lower. These conditions result in high fluxes (400–800 m3 m−2 h−1 at 450 kPa) and emulsions of about 0.5 μm after 5 emulsification cycles. Droplet break-up mechanisms differ in the first emulsification cycle depending on the pore size and geometry of the micro-sieve.
Wael Kaade; Montse Ferrando; Asad Khanmohammed; Carles Torras; Silvia De Lamo-Castellví; Carme Güell. Low-energy high-throughput emulsification with nickel micro-sieves for essential oils encapsulation. Journal of Food Engineering 2019, 263, 326 -336.
AMA StyleWael Kaade, Montse Ferrando, Asad Khanmohammed, Carles Torras, Silvia De Lamo-Castellví, Carme Güell. Low-energy high-throughput emulsification with nickel micro-sieves for essential oils encapsulation. Journal of Food Engineering. 2019; 263 ():326-336.
Chicago/Turabian StyleWael Kaade; Montse Ferrando; Asad Khanmohammed; Carles Torras; Silvia De Lamo-Castellví; Carme Güell. 2019. "Low-energy high-throughput emulsification with nickel micro-sieves for essential oils encapsulation." Journal of Food Engineering 263, no. : 326-336.
A membrane reactor containing an immobilized heterogeneous catalyst is an alternative for traditional homogeneous-based catalyzed transesterification for biodiesel production. Major problems in homogeneous catalysis are related to catalyst recuperation and soap formation, which can be overcome by using heterogeneous catalysts. Conversion can be increased by a combination of reaction and separation, using membranes with a specific pore size. The aim of this work was to study the performance of different membrane reactors combined with heterogeneous catalysis. The main objectives were: to identify a proper catalyst, to choose the proper immobilization technique, to establish the membrane with the adequate pore size, and to control the reaction and separation process. Amberlyst®15 with acid sites and different types of strontium oxide with basic sites were tested as heterogeneous catalysts. Strontium oxide provided the highest sunflower oil conversion (around 93%) and was easy to immobilize. Two catalytic membrane reactor configurations were investigated, thus confirming the production of several types of methyl esters. The configuration comprising the physical immobilization of the catalyst over the membrane reached a methyl ester yield of > 90 wt%.
Monika Hapońska; Claudia Nurra; Sònia Abelló; Michiel Makkee; Joan Salvadó; Carles Torras. Membrane reactors for biodiesel production with strontium oxide as a heterogeneous catalyst. Fuel Processing Technology 2018, 185, 1 -7.
AMA StyleMonika Hapońska, Claudia Nurra, Sònia Abelló, Michiel Makkee, Joan Salvadó, Carles Torras. Membrane reactors for biodiesel production with strontium oxide as a heterogeneous catalyst. Fuel Processing Technology. 2018; 185 ():1-7.
Chicago/Turabian StyleMonika Hapońska; Claudia Nurra; Sònia Abelló; Michiel Makkee; Joan Salvadó; Carles Torras. 2018. "Membrane reactors for biodiesel production with strontium oxide as a heterogeneous catalyst." Fuel Processing Technology 185, no. : 1-7.
The present work focuses on the application of pH-induced sedimentation combined with dynamic filtration for microalgae culture concentration at pilot scale. Concentrations were performed on cultures of two microalgae species: Dunaliella tertiolecta and Chlorella sorokiniana. The objective of the combined process was to reduce microalgae dewatering costs. It is true that sedimentation reduces operation costs considerably, but the results of membrane filtration offer a total rejection and high final concentrations, at even a cheaper cost than centrifugation. When using the two technologies in series, high concentration factors with values up to 207.4 for Dunaliella tertiolecta and 245.3 for Chlorella sorokiniana were achieved. The final concentration of Dunaliella tertiolecta was 184.58 g L−1 with 81.5% of water content in the sludge. The concentrations obtained were high enough to dispense with further operations for the sludge to be ready for a cell disruption step using steam explosion. Analytic techniques used were dry weight and optical density. For the filtration, experiments were performed using both commercially available and self-prepared membranes, manufactured from Acrylonitrile Butadiene Styrene: a novel polymer in membrane technology, selected to reduce costs. Each of them could perform in a similar way to commercial membranes in a pilot scale high-shear stress membrane module.
M. Hapońska; Ester Clavero; J. Salvadó; X. Farriol; C. Torras. Pilot scale dewatering of Chlorella sorokiniana and Dunaliella tertiolecta by sedimentation followed by dynamic filtration. Algal Research 2018, 33, 118 -124.
AMA StyleM. Hapońska, Ester Clavero, J. Salvadó, X. Farriol, C. Torras. Pilot scale dewatering of Chlorella sorokiniana and Dunaliella tertiolecta by sedimentation followed by dynamic filtration. Algal Research. 2018; 33 ():118-124.
Chicago/Turabian StyleM. Hapońska; Ester Clavero; J. Salvadó; X. Farriol; C. Torras. 2018. "Pilot scale dewatering of Chlorella sorokiniana and Dunaliella tertiolecta by sedimentation followed by dynamic filtration." Algal Research 33, no. : 118-124.
M. Hapońska; E. Clavero; J. Salvadó; Carles Torras. Application of ABS membranes in dynamic filtration for Chlorella sorokiniana dewatering. Biomass and Bioenergy 2018, 111, 224 -231.
AMA StyleM. Hapońska, E. Clavero, J. Salvadó, Carles Torras. Application of ABS membranes in dynamic filtration for Chlorella sorokiniana dewatering. Biomass and Bioenergy. 2018; 111 ():224-231.
Chicago/Turabian StyleM. Hapońska; E. Clavero; J. Salvadó; Carles Torras. 2018. "Application of ABS membranes in dynamic filtration for Chlorella sorokiniana dewatering." Biomass and Bioenergy 111, no. : 224-231.
The aim of this study is to explore an innovative downstream route for microalgae processing to reduce cost production. Experiments have been carried out on cell disruption and fractionation stages to recover lipids, sugars, and proteins. Steam explosion and dynamic membrane filtration were used as unit operations. The species tested were Nannochloropsis gaditana, Chlorella sorokiniana, and Dunaliella tertiolecta with different cell wall characteristics. Acid-catalysed steam explosion permitted cell disruption, as well as the hydrolysis of carbohydrates and partial hydrolysis of proteins. This permitted a better access to non-polar solvents for lipid extraction. Dynamic filtration was used to moderate the impact of fouling. Filtration enabled two streams: A permeate containing water and monosaccharides and a low-volume retentate containing the lipids and proteins. The necessary volume of solvent to extract the lipids is thus much lower. An estimation of operational costs of both steam explosion and membrane filtration was performed. The results show that the steam explosion operation cost varies between 0.005 $/kg and 0.014 $/kg of microalgae dry sample, depending on the cost of fuel. Membrane filtration cost in fractionation was estimated at 0.12 $/kg of microalgae dry sample.
Esther Lorente; Monika Haponska; Ester Clavero; Carles Torras; Joan Salvadó. Steam Explosion and Vibrating Membrane Filtration to Improve the Processing Cost of Microalgae Cell Disruption and Fractionation. Processes 2018, 6, 28 .
AMA StyleEsther Lorente, Monika Haponska, Ester Clavero, Carles Torras, Joan Salvadó. Steam Explosion and Vibrating Membrane Filtration to Improve the Processing Cost of Microalgae Cell Disruption and Fractionation. Processes. 2018; 6 (4):28.
Chicago/Turabian StyleEsther Lorente; Monika Haponska; Ester Clavero; Carles Torras; Joan Salvadó. 2018. "Steam Explosion and Vibrating Membrane Filtration to Improve the Processing Cost of Microalgae Cell Disruption and Fractionation." Processes 6, no. 4: 28.
In this study, the microalga Nannochloropsis gaditana was subjected to acid catalysed steam explosion treatment and the resulting exploded material was subsequently fractionated to separate the different fractions (lipids, sugars and solids). Conventional and vibrational membrane setups were used with several polymeric commercial membranes. Two different routes were followed: 1) filtration+lipid solvent extraction and 2) lipid solvent extraction+filtration. Route 1 revealed to be much better since the used membrane for filtration was able to permeate the sugar aqueous phase and retained the fraction containing lipids; after this, an extraction required a much lower amount of solvent and a better recovering yield. Filtration allowed complete lipid rejection. Dynamic filtration improved permeability compared to the tangential cross-flow filtration. Best membrane performance was achieved using a 5000Da membrane with the dynamic system, obtaining a permeability of 6L/h/m/bar.
E. Lorente; M. Hapońska; Ester Clavero; C. Torras; J. Salvadó. Microalgae fractionation using steam explosion, dynamic and tangential cross-flow membrane filtration. Bioresource Technology 2017, 237, 3 -10.
AMA StyleE. Lorente, M. Hapońska, Ester Clavero, C. Torras, J. Salvadó. Microalgae fractionation using steam explosion, dynamic and tangential cross-flow membrane filtration. Bioresource Technology. 2017; 237 ():3-10.
Chicago/Turabian StyleE. Lorente; M. Hapońska; Ester Clavero; C. Torras; J. Salvadó. 2017. "Microalgae fractionation using steam explosion, dynamic and tangential cross-flow membrane filtration." Bioresource Technology 237, no. : 3-10.
Miniaturized cells can be used in photo-electrochemistry to perform water splitting. The geometry, process variables and removal of oxygen bubbles in these cells need to be optimized. Bubbles tend to remain attached to the catalytic surface, thus blocking the reaction, and they therefore need to be dragged out of the cell. Computational Fluid Dynamics simulations have been carried out to assess the design of miniaturized cells and their results have been compared with experimental results. It has been found that low liquid inlet velocities (~0.1 m/s) favor the homogeneous distribution of the flow. Moderate velocities (0.5–1 m/s) favor preferred paths. High velocities (~2 m/s) lead to turbulent behavior of the flow, but avoid bubble coalescence and help to drag the bubbles. Gravity has a limited effect at this velocity. Finally, channeled cells have also been analyzed and they allow a good flow distribution, but part of the catalytic area could be lost. The here presented results can be used as guidelines for the optimum design of photocatalytic cells for the water splitting reaction for the production of solar fuels, such as H2 or other CO2 reduction products (i.e., CO, CH4, among others).
Carles Torras; Esther Lorente; Simelys Hernández; Nunzio Russo; Joan Salvadó. Hydrodynamics and Oxygen Bubble Characterization of Catalytic Cells Used in Artificial Photosynthesis by Means of CFD. Fluids 2017, 2, 25 .
AMA StyleCarles Torras, Esther Lorente, Simelys Hernández, Nunzio Russo, Joan Salvadó. Hydrodynamics and Oxygen Bubble Characterization of Catalytic Cells Used in Artificial Photosynthesis by Means of CFD. Fluids. 2017; 2 (2):25.
Chicago/Turabian StyleCarles Torras; Esther Lorente; Simelys Hernández; Nunzio Russo; Joan Salvadó. 2017. "Hydrodynamics and Oxygen Bubble Characterization of Catalytic Cells Used in Artificial Photosynthesis by Means of CFD." Fluids 2, no. 2: 25.
There are a variety of methods used to determine the porosity of a membrane, such as mercury porosimetry, microscopy, physisorption, etc. (Mulder 1996; Palacio 1999). And from them, the method that provides more information about the whole porous structure of a membrane is, probably, scanning electron microscopy (SEM) by obtaining surface and cross-section membrane micrographs (Kools 1998). Often, the pore size, shape, etc. of a membrane are different depending on the position and caused by the process of membrane formation. These variations are considered through several morphological parameters such as regularity, symmetry, etc. (Torras and Garcia-Valls 2004). They imply significant effects to the membrane performance (Torras et al. 2006). But an inconvenient of SEM technique is that it provides only qualitative results through micrographs (Torras and Garcia-Valls 2004). Thus, it is necessary to interpret the images numerically for a variety of reasons: obtain correlations between mem ...
Carles Torras Font. Texture Recognition. Encyclopedia of Membranes 2016, 1887 -1889.
AMA StyleCarles Torras Font. Texture Recognition. Encyclopedia of Membranes. 2016; ():1887-1889.
Chicago/Turabian StyleCarles Torras Font. 2016. "Texture Recognition." Encyclopedia of Membranes , no. : 1887-1889.
Several characteristics make Phaeodactylum tricornutum potential candidate for biofuels production such as methane and biodiesel. For this reason, some alternatives are evaluated in this manuscript to improve the conversion of this microalgae into methane. One of these alternatives is the addition of sewage sludge to Phaeodactylum tricornutum for anaerobic co-digestion. Although the co-digestion resulted in lack of synergy, the absence of inhibition indicated that both substrates could be co-digested under certain circumstances, for example if microalgae are cultivated for wastewater treatment purposes. The extraction of lipids using organic solvents has been evaluated for biodiesel production but also as a pre-treatment for anaerobic digestion. The results revealed that the type of solvent influences lipid and biodiesel yields. The high polarity of the mixture methanol/hexane increased the lipid and the biodiesel yields from 10 ± 1 to 53 ± 2 gLipids/100 gVS and from 7 ± 1 to 11 ± 1 gBiodiesel/100 gVS compared with hexane. However, none of these solvents affected the composition of biodiesel. Regarding the methane production after the extraction, it yielded 257 ± 8 and 180 ± 6 mLCH4/gVS from lipid-extracted P. tricornutum using hexane and methanol/hexane respectively. The methane production from the raw microalga was 258 ± 5 mLCH4/gVS in the same experiment. The difference in methane production, mainly after the extraction with methanol/hexane, was a consequence of the changes in the composition of the microalgae after extraction. The extraction did not influence the biodegradability. The ultrasonic pre-treatment prior anaerobic digestion completely disrupted the microalgae cells, but the solubilisation of the organic fraction was scarce (<9.5%). The methane production from pre-treated samples was barely 10-11% higher than the obtained from non pre-treated samples, indicating that the refractory nature of the organic fraction in P. tricornutum is the main obstacle for the methane production.
M.P. Caporgno; M. Olkiewicz; C. Torras; J. Salvadó; E. Clavero; C. Bengoa. Effect of pre-treatments on the production of biofuels from Phaeodactylum tricornutum. Journal of Environmental Management 2016, 177, 240 -246.
AMA StyleM.P. Caporgno, M. Olkiewicz, C. Torras, J. Salvadó, E. Clavero, C. Bengoa. Effect of pre-treatments on the production of biofuels from Phaeodactylum tricornutum. Journal of Environmental Management. 2016; 177 ():240-246.
Chicago/Turabian StyleM.P. Caporgno; M. Olkiewicz; C. Torras; J. Salvadó; E. Clavero; C. Bengoa. 2016. "Effect of pre-treatments on the production of biofuels from Phaeodactylum tricornutum." Journal of Environmental Management 177, no. : 240-246.
M. P. Caporgno; E. Clavero; C. Torras; Joan Salvadó; O. Lepine; J. Pruvost; J. Legrand; Jaume Giralt; C. Bengoa. Energy and Nutrients Recovery from Lipid-Extracted Nannochloropsis via Anaerobic Digestion and Hydrothermal Liquefaction. ACS Sustainable Chemistry & Engineering 2016, 4, 3133 -3139.
AMA StyleM. P. Caporgno, E. Clavero, C. Torras, Joan Salvadó, O. Lepine, J. Pruvost, J. Legrand, Jaume Giralt, C. Bengoa. Energy and Nutrients Recovery from Lipid-Extracted Nannochloropsis via Anaerobic Digestion and Hydrothermal Liquefaction. ACS Sustainable Chemistry & Engineering. 2016; 4 (6):3133-3139.
Chicago/Turabian StyleM. P. Caporgno; E. Clavero; C. Torras; Joan Salvadó; O. Lepine; J. Pruvost; J. Legrand; Jaume Giralt; C. Bengoa. 2016. "Energy and Nutrients Recovery from Lipid-Extracted Nannochloropsis via Anaerobic Digestion and Hydrothermal Liquefaction." ACS Sustainable Chemistry & Engineering 4, no. 6: 3133-3139.
Solid material with a circular cross section (or with circularities near 1). Typical sizes of macrocapsules (also named capsules) are between hundreds of micrometers to millimeters. Macrocapsules have a thick porous wall with a small empty core (or nonexistent empty core) (Pena et al. 2009). This characteristic causes the differentiation between them and macrospheres, which are similar but have a dense and thin wall and a large empty volume inside (Lakshmi et al. 2012). A main use of macrocapsules is to store compounds inside, which are released in a controlled way and from different parameters (Pena et al. 2009). First of all, there should be a driven force that usually is concentration gradient. Secondly, permeability occurs through the wall due to convection and diffusion. Depending on the type of process, each of them can be the predominant. For instance, considering macrocapsules with dense and thick wall, where only a concentration gradient occurs, diffusion is predominant and all ...
Carles Torras Font. Macrocapsules. Encyclopedia of Membranes 2015, 1 -2.
AMA StyleCarles Torras Font. Macrocapsules. Encyclopedia of Membranes. 2015; ():1-2.
Chicago/Turabian StyleCarles Torras Font. 2015. "Macrocapsules." Encyclopedia of Membranes , no. : 1-2.
One of the challenges in membrane technology is predicting permeability in porous membranes for liquid applications in an easy and inexpensive way. This is the aim of this work. To achieve this objective, several techniques can be considered. In this study, a morphological approach from two-dimensional scanning electron micrographs is proposed. First, numerical membrane morphological parameters have been determined from micrographs by using the QUANTS tool, which applies a texture recognition process. Second, the obtained data have been fit to the Darcy's and Hagen–Poiseuille models to calculate permeations. The QUANTS results have also been compared with the ones obtained through a mercury porosimeter, which is a classic and well-known methodology. Each parameter of the Hagen–Poiseuille model has been analyzed. A comparison between experimentally measured permeations and calculated ones has been performed. An even easier approach is proposed to predict flow rate with the only knowledge of membrane surface mean pore size. This method is based on cross-section pore size interpolation by using function fits from surface mean pore sizes. The obtained results show a reasonable agreement between measured and computed results, making this technique a valid approach for predicting membrane permeability. POLYM. ENG. SCI., 2015. © 2015 Society of Plastics Engineers
Claudia Nurra; Raphaelle Carraud; Said Pertuz; Domenec Puig; Miguel A. García; Joan Salvadó; Carles Torras; Luizildo Pitol-Filho. Toward the prediction of porous membrane permeability from morphological data. Polymer Engineering & Science 2015, 56, 118 -124.
AMA StyleClaudia Nurra, Raphaelle Carraud, Said Pertuz, Domenec Puig, Miguel A. García, Joan Salvadó, Carles Torras, Luizildo Pitol-Filho. Toward the prediction of porous membrane permeability from morphological data. Polymer Engineering & Science. 2015; 56 (1):118-124.
Chicago/Turabian StyleClaudia Nurra; Raphaelle Carraud; Said Pertuz; Domenec Puig; Miguel A. García; Joan Salvadó; Carles Torras; Luizildo Pitol-Filho. 2015. "Toward the prediction of porous membrane permeability from morphological data." Polymer Engineering & Science 56, no. 1: 118-124.
Pinus sp. sawdust was pretreated by the ethanosolv process using AlCl3, FeCl3, and H2SO4 as catalysts in order to be compared with the methods that are traditionally used to recover cellulose. The ethanosolv process was carried out using different catalysts, different processing time (30, 45, and 60 min), and different temperatures (170,180°C) according to a 3 × 3 × 2 full-factorial experimental design. For cellulose recovery, lower times and temperatures produced the highest yields (up to 58% dry based). Acetylation of the lignocellulosic material obtained was done using acetic anhydride and sulfuric acid. The esterification degree (%ED) of the material was measured by saponification and back-titration of the residual NaOH. Values of %ED ranged from 25.62 ± 1.21 to 39.62 ± 1.75 with no significant differences among treatments. The acetylated cellulose was recovered with methylene chloride and membranes were produced by the EP method. In order to characterize the films obtained, FTIR, SEM, and Rheometry analysis were performed. Infrared spectra revealed acetylation. Microscopy evidenced dense materials for all conditions, and membrane thickness was calculated. Membranes with the highest Young modulus (YM = 297.2 Pa) were produced with the chemically pulped cellulose. The membranes obtained are useful for micro- and ultrafiltration processes; a strong correlation in rejection was related with lignin content of the raw acetylated material. Water fluxes ranged from 10.45 to 51.56 L h−1 m−2 bar−1 and calcium rejection values were up to 89.75%.
Lourdes Ballinas; Tania Saucedo-Acosta; Karen MacDonald-Pizaña; Karla Ruiz-Cuilty; Guadalupe Virginia Nevarez-Moorillon; Nestor Gutiérrez-Méndez; Carles Torras-Font; David Chávez-Flores; Guillermo González Sánchez. Organosolv pretreatment for cellulose recovery from sawdust for its ulterior use in membrane synthesis and operation. DESALINATION AND WATER TREATMENT 2015, 56, 3626 -3639.
AMA StyleLourdes Ballinas, Tania Saucedo-Acosta, Karen MacDonald-Pizaña, Karla Ruiz-Cuilty, Guadalupe Virginia Nevarez-Moorillon, Nestor Gutiérrez-Méndez, Carles Torras-Font, David Chávez-Flores, Guillermo González Sánchez. Organosolv pretreatment for cellulose recovery from sawdust for its ulterior use in membrane synthesis and operation. DESALINATION AND WATER TREATMENT. 2015; 56 (13):3626-3639.
Chicago/Turabian StyleLourdes Ballinas; Tania Saucedo-Acosta; Karen MacDonald-Pizaña; Karla Ruiz-Cuilty; Guadalupe Virginia Nevarez-Moorillon; Nestor Gutiérrez-Méndez; Carles Torras-Font; David Chávez-Flores; Guillermo González Sánchez. 2015. "Organosolv pretreatment for cellulose recovery from sawdust for its ulterior use in membrane synthesis and operation." DESALINATION AND WATER TREATMENT 56, no. 13: 3626-3639.
Among different strategies to reduce costs in microalgae dewatering process via cross-flow filtration, the one related to membrane material was investigated in order to be decreased. Several materials were tested, starting with the ones commonly used in membrane technology [ceramic, polysulfone (PSf) and polyacrylonitrile (PAN)] to the ones generally employed in packaging industry [acrylonitrile butadiene styrene (ABS), glycol-modified polyethylene terephthalate (PETG) and polylactic acid (PLA)], the latter being considerably cheaper. Experiments carried out showed promising results in terms of permeabilities for PSf–Pluronic® F127 blended membranes and PAN membranes (11 ± 1 L/h/m2/bar and 22 ± 1 L/h/m2/bar, respectively, instead of 2 ± 2 L/h/m2/bar of PSf membranes), but with high related costs. PLA membranes showed good mechanical properties, biodegradability and price, but low permeability values (5 ± 1 L/h/m2/bar). PETG membranes showed attractive results in terms of costs and permeability, but poor mechanical properties. The polymer that offered the best results was the ABS that reached membrane permeabilities of 19 ± 1 L/h/m2/bar, maintaining good mechanical properties while filtering the microalgae Phaeodactylum tricornutum Bohlin. Thus, a novel functionality was found for these not so common polymers in microalgae dewatering. This indicates that use of these materials could also be considered in other aqueous micro/ultrafiltration applications. In addition, the biodegradable PLA polymer introduces a new concept of cheap and environmental friendly membrane in this application.
Claudia Nurra; Edgar Franco; Maria L. Maspoch; Joan Salvadó; Carles Torras. Cheaper membrane materials for microalgae dewatering. Journal of Materials Science 2014, 49, 7031 -7039.
AMA StyleClaudia Nurra, Edgar Franco, Maria L. Maspoch, Joan Salvadó, Carles Torras. Cheaper membrane materials for microalgae dewatering. Journal of Materials Science. 2014; 49 (20):7031-7039.
Chicago/Turabian StyleClaudia Nurra; Edgar Franco; Maria L. Maspoch; Joan Salvadó; Carles Torras. 2014. "Cheaper membrane materials for microalgae dewatering." Journal of Materials Science 49, no. 20: 7031-7039.
10.1016/j.biortech.2014.04.009A 53m3 microalgae pilot plant with semi-closed photobioreactors has been operated in batch mode at Tarragona, where proper climatic conditions exist. Operations carried-out were microalgae culturing, concentration, cell disruption and lipid extraction. Culturing was performed with and without CO2 fertilization. pH was used to control CO2 dosing. With CO2 fertilization best microalgae concentrations were obtained. Productivities up to 19.9 g/m2/day were reached. Although sedimentation and centrifugation was performed, studies focused on dynamic membrane filtration as improved technique compared with conventional one. Significant fouling reduction was obtained by using a vibrational membrane setup. Cell disruption including product pre-extraction was performed by using steam explosion at moderate conditions, as novel technique for this application. Lipid extraction was performed by using conventional techniques with and without exploded material. The amount of lipids obtained from exploded material was higher than with non-exploded material, which shows that steam explosion provides a clear enhancement. 2014 Elsevier Ltd. All rights reserved
Claudia Nurra; Carles Torras; Ester Clavero; S. Ríos; M. Rey; E. Lorente; X. Farriol; J. Salvadó. Biorefinery concept in a microalgae pilot plant. Culturing, dynamic filtration and steam explosion fractionation. Bioresource Technology 2014, 163, 136 -142.
AMA StyleClaudia Nurra, Carles Torras, Ester Clavero, S. Ríos, M. Rey, E. Lorente, X. Farriol, J. Salvadó. Biorefinery concept in a microalgae pilot plant. Culturing, dynamic filtration and steam explosion fractionation. Bioresource Technology. 2014; 163 ():136-142.
Chicago/Turabian StyleClaudia Nurra; Carles Torras; Ester Clavero; S. Ríos; M. Rey; E. Lorente; X. Farriol; J. Salvadó. 2014. "Biorefinery concept in a microalgae pilot plant. Culturing, dynamic filtration and steam explosion fractionation." Bioresource Technology 163, no. : 136-142.
10.1016/j.biortech.2014.01.115The effect of shear-enhanced filtration by vibratory process in microalgae dewatering is presented in this paper. The aim of this research was to investigate the technical performance and improvement of vibrating membrane filtration compared with conventional tangential cross-flow filtration in microalgae concentration. An industrial-scale available commercial set-up was used. Several membrane materials as polyethersulfone, polyacrylonitrile, etc., and mean pore sizes (from 7000 Da to 0.2 lm) were tested and compared in both filtration set-ups. Experiments were carried-out with Nannochloropsis gaditana and Phaeodactylum tricornutum microalgae. It has been demonstrated that, even if the choice of the membrane depends on its cut-off, its material and the type of microalgae filtrated, dynamic filtration is always the best technology over a conventional one. If with conventional filtration permeability values were in the vicinity of 10 L/h/m2/bar in steady state phase, with dynamic filtration these values increased to 30 L/h/m2/bar or more. 2014 Elsevier Ltd. All rights reserved
Claudia Nurra; Ester Clavero; Joan Salvadó; Carles Torras. Vibrating membrane filtration as improved technology for microalgae dewatering. Bioresource Technology 2014, 157, 247 -253.
AMA StyleClaudia Nurra, Ester Clavero, Joan Salvadó, Carles Torras. Vibrating membrane filtration as improved technology for microalgae dewatering. Bioresource Technology. 2014; 157 ():247-253.
Chicago/Turabian StyleClaudia Nurra; Ester Clavero; Joan Salvadó; Carles Torras. 2014. "Vibrating membrane filtration as improved technology for microalgae dewatering." Bioresource Technology 157, no. : 247-253.
Image is obtained from a membrane sample to acquire information regarding the morphology of the membrane (porous structure) (Torras et al. 2006). Nevertheless, it can also have other purposes, as characterized by fouling in the membrane (Saha et al. 2007). Typically, micrographs are two-dimensional images, although 3D reconstructions can be obtained by using advanced techniques (i.e., synchrotron) (Remigy et al. 2007). Equipment availability and characterization cost make 2D images to be the routine ones. Several apparatus can be used to obtain membrane micrographs: scanning electron microscopy, transmission electron microscopy, atomic force microscopy, etc. Due to typical sizes of membrane pores (from nanometers to hundreds of micrometers), scanning electron microscopy is, probably, the most versatile equipment. Nevertheless, if special attention is required in the nanometric range, atomic force microscopy may be the most suitable (phase and topographic images can be obtained) (Khulbe ...
Carles Torras Font. Membrane Micrograph. Encyclopedia of Membranes 2014, 1 -2.
AMA StyleCarles Torras Font. Membrane Micrograph. Encyclopedia of Membranes. 2014; ():1-2.
Chicago/Turabian StyleCarles Torras Font. 2014. "Membrane Micrograph." Encyclopedia of Membranes , no. : 1-2.
Several composite membranes have been prepared from cellulose triacetate (CTA) and activated carbon (AC) by solvent casting, varying temperature from 35 to 55°C and relative humidity (RH): 10–70%. Some conditions promoted AC particle agglomeration which is evidenced by SEM and IFME® program. In those membranes, where homogeneity is attained, a deep characterization has been carried out by DMA, MDSC, thermoporometry, solute transport, and AFM. When AC is added in films, Tg is lowered and the fraction of pores with bigger size is augmented. Molecular weight cut off calculated by solute transport, increases from 801.15 to 1194.29 kDa using 1% AC at RH 70% and T 35°C. Water flux is of 5.23 Lm−2 h−1 bar−1. Arsenic removal has been performed, achieving a 45% tested from a 500 ppb arsenic solution, where several factors such as electrical rejection, adsorption and exclusion, could contribute to the total membrane nanofiltration process. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40134.
Luisa Piroshka Terrazas-Bandala; Guillermo González Sánchez; Ricard Garcia-Valls; Tania Gumi; Isabelle Beurroies; Renaud Denoyel; Carles Torras; Lourdes Ballinas. Influence of humidity, temperature, and the addition of activated carbon on the preparation of cellulose acetate membranes and their ability to remove arsenic from water. Journal of Applied Polymer Science 2013, 131, 1 .
AMA StyleLuisa Piroshka Terrazas-Bandala, Guillermo González Sánchez, Ricard Garcia-Valls, Tania Gumi, Isabelle Beurroies, Renaud Denoyel, Carles Torras, Lourdes Ballinas. Influence of humidity, temperature, and the addition of activated carbon on the preparation of cellulose acetate membranes and their ability to remove arsenic from water. Journal of Applied Polymer Science. 2013; 131 (8):1.
Chicago/Turabian StyleLuisa Piroshka Terrazas-Bandala; Guillermo González Sánchez; Ricard Garcia-Valls; Tania Gumi; Isabelle Beurroies; Renaud Denoyel; Carles Torras; Lourdes Ballinas. 2013. "Influence of humidity, temperature, and the addition of activated carbon on the preparation of cellulose acetate membranes and their ability to remove arsenic from water." Journal of Applied Polymer Science 131, no. 8: 1.
10.1016/j.biortech.2013.07.145Microalgae-based biodiesel has several benefits over other resources such as less land use, potential cultivation in non-fertile locations, faster growth and especially a high lipid-to-biodiesel yield. Nevertheless, the environmental and economic behavior for high scale production depends on several variables that must be addressed in the scale-up procedure. In this sense, rigorous modeling and multicriteria evaluation are performed in order to achieve optimal topology for third generation biodiesel production. Different scenarios and the most promising technologies tested at pilot scale are assessed. Besides, the sensitivity analysis allows the detection of key operating variables and assumptions that have a direct effect on the lipid content. The deviation of these variables may lead to an erroneous estimation of the scale-up performance of the technology reviewed in the microalgae-based biodiesel process. The modeling and evaluation of different scenarios of the harvesting, oil extraction and transesterification help to identify greener and cheaper alternatives
Carmen M. Torres; Sergio D. Ríos; Carles Torras; Joan Salvadó; Josep M. Mateo-Sanz; Laureano Jiménez. Microalgae-based biodiesel: A multicriteria analysis of the production process using realistic scenarios. Bioresource Technology 2013, 147, 7 -16.
AMA StyleCarmen M. Torres, Sergio D. Ríos, Carles Torras, Joan Salvadó, Josep M. Mateo-Sanz, Laureano Jiménez. Microalgae-based biodiesel: A multicriteria analysis of the production process using realistic scenarios. Bioresource Technology. 2013; 147 ():7-16.
Chicago/Turabian StyleCarmen M. Torres; Sergio D. Ríos; Carles Torras; Joan Salvadó; Josep M. Mateo-Sanz; Laureano Jiménez. 2013. "Microalgae-based biodiesel: A multicriteria analysis of the production process using realistic scenarios." Bioresource Technology 147, no. : 7-16.
Carmen M. Torres; Sergio D. Ríos; Carles Torras; Joan Salvadó; Josep Maria Mateo-Sanz; Laureano Jiménez. Sustainability analysis of biodiesel production from Cynara Cardunculus crop. Fuel 2013, 111, 535 -542.
AMA StyleCarmen M. Torres, Sergio D. Ríos, Carles Torras, Joan Salvadó, Josep Maria Mateo-Sanz, Laureano Jiménez. Sustainability analysis of biodiesel production from Cynara Cardunculus crop. Fuel. 2013; 111 ():535-542.
Chicago/Turabian StyleCarmen M. Torres; Sergio D. Ríos; Carles Torras; Joan Salvadó; Josep Maria Mateo-Sanz; Laureano Jiménez. 2013. "Sustainability analysis of biodiesel production from Cynara Cardunculus crop." Fuel 111, no. : 535-542.