Experimental determination of dynamic pseudo-equilibrium moisture content: A practical limit for the drying process
Simulation and rigorous design of industrial dryers combine a large number of models, which feed three fundamental balances: (1) mass; (2) energy; and (3) quantity of movement of the material through the dryer. Many of these models represent physical phenomena affecting the three balances at the sam...
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| Format: | Article |
| Language: | English |
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Elsevier
2023-12-01
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| Series: | MethodsX |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2215016123004065 |
| _version_ | 1797405470629036032 |
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| author | Alexis Manuel Faneite Noguera Ignacio Angós Iturgaiz |
| author_facet | Alexis Manuel Faneite Noguera Ignacio Angós Iturgaiz |
| author_sort | Alexis Manuel Faneite Noguera |
| collection | DOAJ |
| description | Simulation and rigorous design of industrial dryers combine a large number of models, which feed three fundamental balances: (1) mass; (2) energy; and (3) quantity of movement of the material through the dryer. Many of these models represent physical phenomena affecting the three balances at the same time, which makes these calculations extremely complex, hence, accurate models are essential. The hypothesis that the kinetic stage of drying of any material culminates in the thermodynamic moisture equilibrium between solid and drying gas has been in effect for many years. However, recent findings show that there is a transition stage between the kinetic stage and the thermodynamic equilibrium, which, experimentally, looks like an equilibrium. The beginning of this transition stage or dynamic pseudo-equilibrium stage would mark the end of the drying kinetics models, which has been named as the dynamic pseudo-equilibrium moisture contents (Xdpe). The non-observance of this phenomenon presupposes a model limited in its prediction capacity, especially in the last stages of drying and even more so at low drying temperatures. As a consequence, sizes of industrial dryers could be underestimated during the simulation and rigorous design process, or underestimate drying times, in batch dryers. On the other hand, the optimal conditions may never be found, during the optimization of existing industrial drying processes. The objective of this work is to present the procedure to determine Xdpe, during the experimental determination of drying curves of any material. Likewise, to propose the practical moisture ratio, which uses Xdpe, instead of the equilibrium moisture, to be used in the modeling of the drying kinetics. • The drying process is divided into three stages: kinetic, transition, and equilibrium. • The dynamic pseudo-equilibrium moisture content divides the kinetic and the transition stages. • The practical moisture ratio should be used in rigorous industrial dryer design calculations. |
| first_indexed | 2024-03-09T03:10:24Z |
| format | Article |
| id | doaj.art-dd4c8fd8a2e2482dbbc69de778437d71 |
| institution | Directory Open Access Journal |
| issn | 2215-0161 |
| language | English |
| last_indexed | 2024-03-09T03:10:24Z |
| publishDate | 2023-12-01 |
| publisher | Elsevier |
| record_format | Article |
| series | MethodsX |
| spelling | doaj.art-dd4c8fd8a2e2482dbbc69de778437d712023-12-04T05:22:37ZengElsevierMethodsX2215-01612023-12-0111102410Experimental determination of dynamic pseudo-equilibrium moisture content: A practical limit for the drying processAlexis Manuel Faneite Noguera0Ignacio Angós Iturgaiz1Laboratory of Chemical Engineering, Faculty of Engineering, School of Chemical Engineering, University of Zulia (LUZ), Guajira Avenue, Campus “Dr. Antonio Borjas Romero”, Maracaibo 4001, Venezuela; Department of Research, Development & Innovation, Industrial Dryers of Venezuela Corporation (SECAVENCA), Maracaibo 4001, VenezuelaPublic University of Navarre (UPNA), Department of Agricultural Engineering and Biosciences, Institute for Innovation & Sustainable Food Chain Development (ISFOOD), Campus de Arrosadia, 31006 Pamplona, Spain; Corresponding author.Simulation and rigorous design of industrial dryers combine a large number of models, which feed three fundamental balances: (1) mass; (2) energy; and (3) quantity of movement of the material through the dryer. Many of these models represent physical phenomena affecting the three balances at the same time, which makes these calculations extremely complex, hence, accurate models are essential. The hypothesis that the kinetic stage of drying of any material culminates in the thermodynamic moisture equilibrium between solid and drying gas has been in effect for many years. However, recent findings show that there is a transition stage between the kinetic stage and the thermodynamic equilibrium, which, experimentally, looks like an equilibrium. The beginning of this transition stage or dynamic pseudo-equilibrium stage would mark the end of the drying kinetics models, which has been named as the dynamic pseudo-equilibrium moisture contents (Xdpe). The non-observance of this phenomenon presupposes a model limited in its prediction capacity, especially in the last stages of drying and even more so at low drying temperatures. As a consequence, sizes of industrial dryers could be underestimated during the simulation and rigorous design process, or underestimate drying times, in batch dryers. On the other hand, the optimal conditions may never be found, during the optimization of existing industrial drying processes. The objective of this work is to present the procedure to determine Xdpe, during the experimental determination of drying curves of any material. Likewise, to propose the practical moisture ratio, which uses Xdpe, instead of the equilibrium moisture, to be used in the modeling of the drying kinetics. • The drying process is divided into three stages: kinetic, transition, and equilibrium. • The dynamic pseudo-equilibrium moisture content divides the kinetic and the transition stages. • The practical moisture ratio should be used in rigorous industrial dryer design calculations.http://www.sciencedirect.com/science/article/pii/S2215016123004065Determination of dynamic pseudo-equilibrium moisture contents in an experimental drying kinetics study, and calculation of the practical moisture ratio for the modeling of said experimental kinetics, for use in rigorous design and simulation of industrial dryers |
| spellingShingle | Alexis Manuel Faneite Noguera Ignacio Angós Iturgaiz Experimental determination of dynamic pseudo-equilibrium moisture content: A practical limit for the drying process MethodsX Determination of dynamic pseudo-equilibrium moisture contents in an experimental drying kinetics study, and calculation of the practical moisture ratio for the modeling of said experimental kinetics, for use in rigorous design and simulation of industrial dryers |
| title | Experimental determination of dynamic pseudo-equilibrium moisture content: A practical limit for the drying process |
| title_full | Experimental determination of dynamic pseudo-equilibrium moisture content: A practical limit for the drying process |
| title_fullStr | Experimental determination of dynamic pseudo-equilibrium moisture content: A practical limit for the drying process |
| title_full_unstemmed | Experimental determination of dynamic pseudo-equilibrium moisture content: A practical limit for the drying process |
| title_short | Experimental determination of dynamic pseudo-equilibrium moisture content: A practical limit for the drying process |
| title_sort | experimental determination of dynamic pseudo equilibrium moisture content a practical limit for the drying process |
| topic | Determination of dynamic pseudo-equilibrium moisture contents in an experimental drying kinetics study, and calculation of the practical moisture ratio for the modeling of said experimental kinetics, for use in rigorous design and simulation of industrial dryers |
| url | http://www.sciencedirect.com/science/article/pii/S2215016123004065 |
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