High pressure vapour-liquid equilibrium of volatiles in supercritical carbon dioxide

Binary vapour-liquid equilibrium of thymoquinone and carbon dioxide at the isothermal conditions was carried out at temperature 323.15 K and pressures from 6 to 10 MPa. The experimental data were fitted to the Soave-Redlich-Kwong equation of state. Results could be used for selection of process parameters in separation of volatiles from raw oil or for evaluation of existing separation technologies

Evaluation of the addition of artichoke by-products to O/W emulsions for oil microencapsulation by spray drying

[EN] This study aimed to evaluate the use of artichoke bracts in oil microencapsulation by spray drying. Thus, 1% and 2% w/w of this material was added to sunflower O/W emulsions to partially replace maltodextrin and substitute Tween (R) 20. Emulsions were compared with a control containing only maltodextrin as wall material and Tween (R) 20 as emulsifier. The emulsion containing 2% of artichoke exhibited higher (p < 0.05) viscosity and stability against coalescence and flocculation (24 h) and 20% higher encapsulation efficiency after spray drying, compared with control. The three microcapsules showed similar microstructure, density, porosity, flow properties, and Tg. Microcapsules containing artichoke exhibited, on average, 15% larger particles, 19% lower moisture content, and 9% lower solubility, besides perceptible colour changes. Microcapsules containing artichoke (2%) showed lower oxidation indicators content (37%) after spray drying and over 2 months of controlled storage (35 degrees C, 50% relative humidity) than control. After 90 days, decreases in linoleic acid were observed in all the samples (up to 24%), with increases of oleic and saturated fatty acids. The control showed the highest increase in saturated fatty acids (73%). Hence, artichoke bracts can be exploited for their application in lipid microencapsulation because of their emulsifier properties and the oxidative protection they provide.The authors acknowledge the financial support of the National Institute of Research and Agri-Food Technology (INIA) , ERDF funds EU, and the Spanish research agency (AEI) (RTA2015-00060-C04-03 and RTA2015-00060-C04-02) , and the AEI (PID2019-106148RR-C43 AEI 10.13039/501100011033 and PID2019-106148RRC42 AEI 10.13039/501100011033 projects) ; and the Ministry of Science Innovation and Universities (MCIU) for the research fellowship (FPU15/03040) and the mobility aid (EST17/00152) . We would also like to thank Dr. Fernando Hierro, Trinidad Garcia, Josep Agusti Pablo C`anaves, and Dr. Joan Cifre Bauz`a, from the "Serveis Cientificote`cnics" of the University of the Balearic Islands for their assistance with SEM and optical microscopy, gas chromatography, HPLC and TGA and DSC respectively.Umaña, M.; Wawrzyniak, P.; Rossello Matas, C.; Llavata-Cabrero, B.; Simal Florindo, S. (2021). Evaluation of the addition of artichoke by-products to O/W emulsions for oil microencapsulation by spray drying. LWT - Food Science and Technology. 151:1-12. https://doi.org/10.1016/j.lwt.2021.11214611215

Concept of heat recovery in drying with chemical heat pump

[EN] Drying is one of the most energy intensive unit operations. It easily accounts for up to 15% of all industrial energy consumption. In the most drying processes heat is required to evaporate moisture which is later removed with a flow of air. The hot, humid air leaving the dryer is often considered as a waste stream, and a large fraction of energy is lost. The aim of the theoretical and experimental concept study presented here was to evaluate a method of reclaiming energy from low temperature waste streams and converting it to useful in industry saturated steam of temperature from 120 to 150 °C. Chemical heat pump concept based on the dilution and concentration of phosphoric acid was used to test the method in the laboratory. Heat of dilution and energy needed for water evaporation from the acid solution were experimentally measured. The cycle of successive processes of dilution and concentration has been experimentally confirmed. Theoretical model of the chemical heat pump was tested and coefficient of performance measured. Energy balance of the drying system and efficiency increase of the dryer supported with chemical heat pump were calculated.The authors wish to acknowledge the support of the Chemat Sp. z o.o. and Nationa Centre for Research and Development (POIR.01.01.01-00-0809/17-00) for this study.Tylman, M.; Jaskulski, M.; Wawrzyniak, P.; Czapnik, M. (2018). Concept of heat recovery in drying with chemical heat pump. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat Politècnica de València. 1391-1398. https://doi.org/10.4995/IDS2018.2018.7271OCS1391139

Superheated Steam Spray Drying as an Energy-Saving Drying Technique: A Review

Drying is an extremely energy-intensive process. Superheated steam as a drying medium can improve the energy efficiency of the drying processes. In superheated steam drying, waste heat can be recovered by condensing the exhaust steam or raising its specific enthalpy. Spray drying is widely used in industry, even though its energy efficiency is often low. Substitution of air by superheated steam as a drying medium in a spray dryer may reduce the energy consumption of the drying process by 20–30%; moreover, if excess steam generated by moisture evaporation is upgraded to a higher temperature level and reused for drying, the energy demand could be decreased by even 80%. A literature review showed that superheated steam spray drying was successfully applied for both thermally resistant and a wide range of thermally sensitive materials. Superheated steam drying gives a number of advantages in terms of product properties, i.e., higher particle porosity due to rapid moisture evaporation results in improved powder rehydration properties. Additionally, steam drying may be applied for in situ particle crystallization. Taking into account the advantages of superheated steam drying and the potential application of this technology in spray drying systems, there is a great need for further research in this field. This literature review aimed to present an energy-saving solution, i.e., superheated steam spray drying process, showing its advantages and potential applications, followed by drying kinetics, providing analysis of the research papers on experimental studies as well as mathematical modeling of this drying technique

Superheated Steam Spray Drying as an Energy-Saving Drying Technique: A Review

Drying is an extremely energy-intensive process. Superheated steam as a drying medium can improve the energy efficiency of the drying processes. In superheated steam drying, waste heat can be recovered by condensing the exhaust steam or raising its specific enthalpy. Spray drying is widely used in industry, even though its energy efficiency is often low. Substitution of air by superheated steam as a drying medium in a spray dryer may reduce the energy consumption of the drying process by 20&ndash;30%; moreover, if excess steam generated by moisture evaporation is upgraded to a higher temperature level and reused for drying, the energy demand could be decreased by even 80%. A literature review showed that superheated steam spray drying was successfully applied for both thermally resistant and a wide range of thermally sensitive materials. Superheated steam drying gives a number of advantages in terms of product properties, i.e., higher particle porosity due to rapid moisture evaporation results in improved powder rehydration properties. Additionally, steam drying may be applied for in situ particle crystallization. Taking into account the advantages of superheated steam drying and the potential application of this technology in spray drying systems, there is a great need for further research in this field. This literature review aimed to present an energy-saving solution, i.e., superheated steam spray drying process, showing its advantages and potential applications, followed by drying kinetics, providing analysis of the research papers on experimental studies as well as mathematical modeling of this drying technique

Evaluation of 3T proton MR spectroscopy in the spinal cord : preliminary results

Purpose: 1H-magnetic resonance spectroscopy (1H-MRS) is a non-invasive technique that provides information on tissue metabolism and biochemistry. Because of technical difficulties, this method is rarely used in spinal cord examination. The main goal of this study was to develop a routine protocol for MRS of intramedullary lesions. Material and methods: A 1H-MRS protocol was set on a group of healthy volunteers. Forty-eight spectra were acquired in total. Thirty of them were acquired in cervical spinal cord, and the remaining 18 spectra were acquired in the thoracic spinal cord. Results: In 1H-MRS of the spinal cord one of the most important problems is small voxel size. Mean voxel size in this study was 7 × 9 × 29 mm, which is much smaller than in brain examinations. Finally, almost 60% of spectra were of acceptable quality in volunteer examinations, which enabled the subsequent examinations. Conclusions: Challenges of spinal cord spectroscopy were discussed, and the ability of providing additional diagnostic information was proven

Evaluation of the addition of artichoke by-products to O/W emulsions for oil microencapsulation by spray drying

[eng] This study aimed to evaluate the use of artichoke bracts in oil microencapsulation by spray drying. Thus, 1% and 2% w/w of this material was added to sunflower O/W emulsions to partially replace maltodextrin and substitute Tween®20. Emulsions were compared with a control containing only maltodextrin as wall material and Tween®20 as emulsifier. The emulsion containing 2% of artichoke exhibited higher (p < 0.05) viscosity and stability against coalescence and flocculation (24 h) and 20% higher encapsulation efficiency after spray drying, compared with control. The three microcapsules showed similar microstructure, density, porosity, flow properties, and Tg. Microcapsules containing artichoke exhibited, on average, 15% larger particles, 19% lower moisture content, and 9% lower solubility, besides perceptible colour changes. Microcapsules containing artichoke (2%) showed lower oxidation indicators content (37%) after spray drying and over 2 months of controlled storage (35 °C, 50% relative humidity) than control. After 90 days, decreases in linoleic acid were observed in all the samples (up to 24%), with increases of oleic and saturated fatty acids. The control showed the highest increase in saturated fatty acids (73%). Hence, artichoke bracts can be exploited for their application in lipid microencapsulation because of their emulsifier properties and the oxidative protection they provide

Clinical outcome and patient satisfaction using biodegradable (NasoPore) and non-biodegradable packing, a double-blind, prospective, randomized study

Abstract Introduction Nasal packing after endoscopic sinus surgery is used as a standard procedure. The optimum solution to minimize or eliminate all disadvantages of this procedure may be accomplished using biodegradable packs. Objective The aim of this study was to compare patient satisfaction and clinical outcome associated with absorbable and non-absorbable packing after FESS. Methods In total, 50 patients were included in a prospective, double-blind, randomized trial. One side was packed with polyurethane foam, while the opposite side was packed with gauze packing. On the 2nd, 10th, and 30th postoperative day, the patients were questioned with the aid of a visual analog scale. The standardized questionnaires for bleeding, nasal breathing, feeling of pressure, and headache were used. The presence of synechiae, infection, or granulation was noted and recorded with the video-endoscopy. Results A significant difference according to lower pressure was found in the NasoPore group compared to the controls on day ten after surgery. The NasoPore packing had lower scores with respect to postoperative nose blockage on the 2nd and 10th days. Mucosal healing was better for the NasoPore group, both at day ten and 30 compared with the control group. Conclusion The overall patient comfort is higher when using NasoPore compared to non-resorbable traditional impregnated gauze packing. Intensive saline douches applied three to four times per day are mandatory after the operation to prevent synechiae formation and fluid resorption by the packing