scholarly journals Quantitative of Mass Transfer in Liquid-Liquid Operations of Oil-Alcohol-Glycerin Systems

2021 ◽  
Author(s):  
Benjamim H.L. Silva ◽  
Cesar A.M. Abreu
Keyword(s):  
Mass Transfer ◽  
Distribution Coefficients ◽  
Physical Parameters ◽  
Transfer Coefficients ◽  
Heterogeneous Model ◽  
Physical Mechanisms ◽  
Liquid Phases ◽  
Partially Miscible ◽  
Effective Performance ◽  
Average Distribution

The effects of mass transfer were quantified for the effective performance of mixtures between partially miscible phases, or for the promotion of their separations. To consolidate the analysis of heterogeneous liquid–liquid processes, variations in the composition of the liquid phases over the evolution of contact operations were considered, detailing the physical mechanisms involved in the mixtures of oil (soy, sunflower) and alcohol (methanol, ethanol), and in the separation between biodiesel and glycerin. Based on experimental evaluations, the average distribution coefficients for triglycerides (oil-alcohol) and glycerol (biodiesel-glycerin) were estimated at 1.31 and 1.46, and 3.42 × 10−2 and 4.06 × 10–2, for soybean and sunflower, respectively, while their mass transfer coefficients, depending on their concentration ranges in the phase, varied in orders of magnitude from 10−2 s−1 to 10–4 s−1. Including the values of the physical parameters, a heterogeneous model for the alkaline transesterification of soybean oil (methanol, ethanol, NaOH, 25°C, 40°C, 60°C, 600 rpm) was validated.

scholarly journals MATHEMATICAL MODELING OF THERMOGRAVITATIONAL AND THERMOCA-PILLARY CONVECTION IN GAS-LIQUID PROCESSES

2021 ◽  
Vol 2021 (1) ◽  
pp. 58-66
Author(s):  
Evgeniy Podoplelov ◽  
Aleksey Bal'chugov ◽  
Anatoliy Dement'ev ◽  
Anatoliy Glotov
Keyword(s):  
Mathematical Modeling ◽  
Mass Transfer ◽  
Phase Boundary ◽  
Mass Exchange ◽  
Exchange Process ◽  
Transfer Coefficients ◽  
Mass Exchange Process ◽  
Convective Flows ◽  
Liquid Phases ◽  
Turbulent Pulsations

. The interaction of gas and liquid phases in some cases is accompanied by the spontaneous occur-rence of convective flows and turbulent pulsations at the phase boundary and in adjacent areas. Hy-drodynamic instability allows to accelerate the interfacial transfer of matter and leads to an increase in mass transfer coefficients. Research in this field is not only theoretical, but also practical, since sur-face convection can be artificially created in apparatus for intensifying the mass exchange process.

Dufour and Soret effects on Al2O3-water nanofluid flow over a moving thin needle: Tiwari and Das model

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Iskandar Waini ◽  
Anuar Ishak ◽  
Ioan Pop
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Skin Friction ◽  
Temporal Stability ◽  
Physical Parameters ◽  
Transfer Coefficients ◽  
Nanofluid Flow ◽  
Content Type

Purpose This paper aims to examine the effect of Dufour and Soret diffusions on Al2O3-water nanofluid flow over a moving thin needle by using the Tiwari and Das model. Design/methodology/approach The governing equations are reduced to the similarity equations using similarity transformations. The resulting equations are programmed in Matlab software through the bvp4c solver to obtain their solutions. The features of the skin friction, heat transfer and mass transfer coefficients, as well as the velocity, temperature and concentration profiles for different values of the physical parameters, are analysed and discussed. Findings The non-uniqueness of the solutions is observed for a certain range of the physical parameters. The authors also notice that the bifurcation of the solutions occurs in which the needle moves toward the origin (λ < 0). It is discovered that the first branch solutions of the skin friction coefficient and the heat transfer coefficients increase, but the mass transfer coefficient decreases in the presence of nanoparticle. Additionally, the simultaneous effect of Dufour and Soret diffusions tends to enhance the heat transfer coefficient; however, dual behaviours are observed for the mass transfer coefficient. Further analysis shows that between the two solutions, only one of them is stable and thus physically reliable in the long run. Originality/value The problem of Al2O3-water nanofluid flow over a moving thin needle with Dufour and Soret effects are the important originality of the present study. Besides, the temporal stability of the dual solutions is examined for time.

scholarly journals Dual solutions for heat and mass transfer in chemically reacting radiative non-Newtonian fluid with aligned magnetic field

2017 ◽  
Vol 14 (1) ◽  
pp. 25-38 ◽  
Author(s):  
J. V. Ramana Reddy ◽  
V. Sugunamma ◽  
N. Sandeep
Keyword(s):  
Magnetic Field ◽  
Mass Transfer ◽  
Differential Equations ◽  
Heat And Mass Transfer ◽  
Stretching Sheet ◽  
Graphical Representation ◽  
Physical Parameters ◽  
Transfer Coefficients ◽  
Chemically Reacting ◽  
Aligned Magnetic Field

Through this paper we investigated the heat and mass transfer in chemically reacting radiative Casson fluid flow over a slandering/flat stretching sheet in a slip flow regime with aligned magnetic field. This study is carried out under the influence of non uniform heat source/sink. First we converted the governing equations of the flow into ordinary differential equations by making use of suitable similarity transformations. The obtained non-linear differential equations are solved numerically using Runge-Kutta based shooting technique. Further, graphical representation has been given to study the effects of various physical parameters on velocity, temperature and concentration fields. Also numerical computations has been carried out to investigate the influence of the physical parameters involved in the flow on skin friction, rate of heat and mass transfer coefficients. Through this investigation, it is observed that aligned angle, Casson parameter and velocity slip parameter have the tendency to control the velocity field. Also heat transfer rate in flat stretching sheet is higher than that of slendering stretching sheet. A good agreement of the present results with the existed literature has been observed. 

scholarly journals MASS TRANSFER COEFFICIENTS BETWEEN GAS AND LIQUID PHASES IN PACKED COLUMNS

1968 ◽  
Vol 1 (1) ◽  
pp. 56-62 ◽  
Author(s):  
KAKUSABURO ONDA ◽  
HIROSHI TAKEUCHI ◽  
YOSHIO OKUMOTO
Keyword(s):  
Mass Transfer ◽  
Packed Columns ◽  
Transfer Coefficients ◽  
Mass Transfer Coefficients ◽  
Liquid Phases

scholarly journals Modeling Drying Characteristics of Terebinth Fruit Under Infrared Fluidized Bed Condition

2015 ◽  
Vol 47 (4) ◽  
pp. 5-21 ◽  
Author(s):  
M. Kaveh ◽  
R. Amiri Chayjan
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Radiation Power ◽  
Process Time ◽  
Physical Parameters ◽  
Drying Process ◽  
Transfer Coefficients ◽  
Air Velocity ◽  
Drying Kinetic ◽  
Fluid Bed

Abstract Advantages of infrared fluid bed drying include high heat and mass transfer coefficients, short process time, high quality and low energy consumption. Since heat and mass transfer and quality changes during drying of terebinth fruit with infrared fluid bed method is not described in the literature. Goals of this research were study the effects of different infrared drying conditions on the drying kinetic and physical parameters of terebinth fruit. To predict moisture during drying process, five mathematical models were used. Experiments were conducted at different levels of hot air velocity (0.93, 1.76 and 2.6 m/s), temperature (40, 55, and 70°C) and infrared radiation power (500, 1000 and 1500 W). Results showed that Demir et al. model had the best performance for predicting of moisture ratio. Effective moisture diffusivity for terebinth samples (6.2×10-11 to 7.3×10-10 m2/s) was achieved. Activation energy of the samples (44.4 to 59.13 kJ/mol) was computed. Maximum rupture force (118.4 N) was calculated at air velocity of 2.6 m/s, infrared power of 1500 W and air temperature of 70°C. The results proved that in addition to short process time, monitoring of terebinth fruit characteristics such as mechanical properties during drying process can be achieved.

Unsteady MHD Free Convective Heat and Mass Transfer Flow Past a Vertical Porous Plate in the Presence of Radiation and Chemical Reaction

2017 ◽  
Vol 6 (10) ◽  
pp. 116
Author(s):  
J. Buggaramulu ◽  
M. Venkatakrishna ◽  
Y. Harikrishna
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Convective Heat ◽  
Chemical Reaction ◽  
Porous Plate ◽  
Physical Parameters ◽  
Governing Equations ◽  
Vertical Porous Plate ◽  
Flow Past ◽  
Transfer Flow

The objective of this paper is to analyze an unsteady MHD free convective heat and mass transfer boundary flow past a semi-infinite vertical porous plate immersed in a porous medium with radiation and chemical reaction. The governing equations of the flow field are solved numerical a two term perturbation method. The effects of the various parameters on the velocity, temperature and concentration profiles are presented graphically and values of skin-frication coefficient, Nusselt number and Sherwood number for various values of physical parameters are presented through tables.

Modeling mass transfer and substrate utilization in the boundary layer of biofilm systems

1998 ◽  
Vol 37 (4-5) ◽  
pp. 139-147 ◽  
Author(s):  
Harald Horn ◽  
Dietmar C. Hempel
Keyword(s):  
Boundary Layer ◽  
Mass Transfer ◽  
Reynolds Number ◽  
Film Theory ◽  
Substrate Utilization ◽  
The Other ◽  
Concentration Profiles ◽  
Hydrodynamic Conditions ◽  
Time Axis ◽  
Transfer Coefficients

The use of microelectrodes in biofilm research allows a better understanding of intrinsic biofilm processes. Little is known about mass transfer and substrate utilization in the boundary layer of biofilm systems. One possible description of mass transfer can be obtained by mass transfer coefficients, both on the basis of the stagnant film theory or with the Sherwood number. This approach is rather formal and not quite correct when the heterogeneity of the biofilm surface structure is taken into account. It could be shown that substrate loading is a major factor in the description of the development of the density. On the other hand, the time axis is an important factor which has to be considered when concentration profiles in biofilm systems are discussed. Finally, hydrodynamic conditions become important for the development of the biofilm surface when the Reynolds number increases above the range of 3000-4000.

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