scholarly journals A Mathematical Modeling of the Reverse Osmosis Concentration Process of a Glucose Solution

Processes ◽  
2019 ◽  
Vol 7 (5) ◽  
pp. 271 ◽  
Author(s):  
Chenghan Chen ◽  
Han Qin
Keyword(s):  
Mathematical Modeling ◽  
Experimental Data ◽  
Mass Transfer ◽  
Reverse Osmosis ◽  
Glucose Solution ◽  
Model Parameters ◽  
Hydraulic Permeability ◽  
Water Separation ◽  
Concentration Process ◽  
Ro Membrane

A mathematical modeling of glucose–water separation through a reverse osmosis (RO) membrane was developed to research the membrane’s performance during the mass transfer process. The model was developed by coupling the concentration–polarization (CP) model, which uses one-dimensional flow assumption, with the irreversible thermodynamic Spiegler–Kedem model. A nonlinear parameter estimation technique was used to determine the model parameters Lp (hydraulic permeability constant), σ (reflection coefficient), and Bs (solute transport coefficient). Experimental data were obtained from the treatment of a pre-treated glucose solution using a laboratory-scale RO system, and studies on the validation of the model using experimental results are presented. The calculated results are consistent with the experimental data. The proposed model describes the RO membrane concentration process and deduces the expression of k (mass transfer coefficient in the CP layer). The verification shows that the expression of k well-describes the reverse osmosis mass transfer of a glucose solution.

Recycling and Extraction of Zinc Ions in Disc-Donut Column Considering Forward Mixing Mass Transfer, Chemical Reaction and Effects of Pulsed and non-Pulsed Condition

2021 ◽  
Author(s):  
Mehdi Asadollahzadeh ◽  
Rezvan Torkaman ◽  
Meisam Torab-Mostaedi ◽  
Mojtaba Saremi
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Flow Rate ◽  
Positive Impact ◽  
Plug Flow ◽  
Model Parameters ◽  
Zinc Ions ◽  
Zinc Extraction ◽  
Balance Equations ◽  
Transfer Rates

Abstract The current study focuses on the recovery of zinc ions by solvent extraction in the pulsed contactor. The Zn(II) ions from chloride solution were extracted into the organic phase containing D2EHPA extractant. The resulting data were characterized for the relative amount of (a) pulsed and no-pulsed condition; and (b) flow rate of both phases. Based on the mass balance equations for the column performance description, numerical computations of mass transfer in a disc-donut column were conducted and validated the experimental data for zinc extraction. Four different models, such as plug flow, backflow, axial dispersion, and forward mixing were evaluated in this study. The results showed that the intensification of the process with the pulsed condition increased and achieved higher mass transfer rates. The forward mixing model findings based on the curve fitting approach validated well with the experimental data. The results showed that an increase in pulsation intensity, as well as the phase flow rates, have a positive impact on the performance of the extractor, whereas the enhancement of flow rate led to the reduction of the described model parameters for adverse phase.

scholarly journals Battery Model Parameters Estimation Using Simulated Annealing

2017 ◽  
Vol 18 (1) ◽  
pp. 127 ◽  
Author(s):  
Marcia De Fatima Brondani ◽  
Airam Teresa Zago Romcy Sausen ◽  
Paulo Sérgio Sausen ◽  
Manuel Osório Binelo
Keyword(s):  
Mathematical Modeling ◽  
Experimental Data ◽  
Simulated Annealing ◽  
Visual Analysis ◽  
Lithium Ion ◽  
Parameters Estimation ◽  
Model Parameters ◽  
Algorithm Efficiency ◽  
Battery Model ◽  
Discharge Curves

In this paper, a Simulated Annealing (SA) algorithm is proposed for the Battery model parametrization, which is used for the mathematical modeling of the Lithium Ion Polymer (LiPo) batteries lifetime. Experimental data obtained by a testbed were used for model parametrization and validation. The proposed SA algorithm is compared to the traditional parametrization methodology that consists in the visual analysis of discharge curves, and from the results obtained, it is possible to see the model efficacy in batteries lifetime prediction, and the proposed SA algorithm efficiency in the parameters estimation.

scholarly journals A Novel Mass Transfer Model to Describe the Separation Process in Reverse Osmosis of Glucose

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Chenghan Chen ◽  
Yanwei Wang ◽  
Furong Tan ◽  
Qili Zhu
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Reverse Osmosis ◽  
Production Efficiency ◽  
Mathematic Model ◽  
Mass Transfer Process ◽  
Theoretical Research ◽  
Transfer Model ◽  
Calculation Results ◽  
Improve Production Efficiency

Basic and theoretical research on processes such as reverse osmosis (RO) is essential in the fermentation industry to improve production efficiency and reduce cost. Here, we focus on the RO concentration of glucose solutions. We constructed a mathematic model that incorporates various membrane and experimental parameters to characterize the mass transfer process of RO membrane and validated the model output with experimental data. Calculation results were highly consistent with the experimental data, demonstrating that this model can be useful for predicting the RO concentration process.

Geometric issues in reverse osmosis: numerical simulation and experimentation

2014 ◽  
Vol 70 (8) ◽  
pp. 1348-1354 ◽  
Author(s):  
G. Srivathsan ◽  
Ephraim Sparrow ◽  
John Gorman
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Fluid Flow ◽  
Velocity Field ◽  
Reverse Osmosis ◽  
Geometric Imperfections ◽  
Flow Channels ◽  
Ro Membrane ◽  
Simulation Results ◽  
Practical Impact

This investigation is a synergistic combination of laboratory experimentation and numerical simulation to quantify the practical impact of geometric imperfections in the flow channels of a reverse osmosis (RO) system. To this end, carefully executed experiments are performed to quantify the fluid flow in a system containing feed spacers which are embedded in the RO membrane. In a complementary activity, numerical simulations were performed both for an ideal geometric situation (without embedments) and the actual geometric configuration including the embedments. It was found that the presence of unaccounted embedments affected the pressure drop predictions for the system by 14–19%. When account was taken of the embedments, the simulation results were found to be virtually coincident with the experimental results. This outcome suggests that deviations between experimental and simulation results encountered in the literature might well have been due to geometrical deviations of the type investigated here. The numerical simulation of the feedwater fluid flow was based on the often-used but unverified assumption that the velocity field experiences the geometric periodicity of the feed spacer. This assumption was lent support by results from a non-periodic simulation model and by the excellent agreement between the numerically based predictions and the experimental data.

Drying of Sisal Fiber: Three-Dimensional Mathematical Modeling and Simulation

2020 ◽  
Vol 399 ◽  
pp. 202-207
Author(s):  
Jaqueline Félix de Brito Diniz ◽  
Gicélia Moreira ◽  
José Jefferson da Silva Nascimento ◽  
Rodolfo Pereira de Farias ◽  
Hortência Luma Fernandes Magalhães ◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Experimental Data ◽  
Mass Transfer ◽  
Moisture Content ◽  
Three Dimensional ◽  
Sisal Fiber ◽  
Average Moisture Content ◽  
Proposed Model ◽  
Volume Method ◽  
Good Agreement

This work presents a theoretical drying study of sisal fiber. Fibers with moisture content of around 11.2% were dried in an oven in the temperature 90°C. A transient and three-dimensional mathematical modeling to predict heat and mass transfer in a bed of fiber was proposed and numerically solved by using the finite-volume method. Results of the average moisture content and surface temperature were compared with experimental data to verify the consistence of the proposed model, and good agreement was verified.

scholarly journals Correlations for Concentration Polarization and Pressure Drop in Spacer-Filled RO Membrane Modules Based on CFD Simulations

Membranes ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 338
Author(s):  
Boram Gu ◽  
Claire S. Adjiman ◽  
Xiao Yun Xu
Keyword(s):  
Mass Transfer ◽  
Pressure Drop ◽  
Friction Factor ◽  
Reverse Osmosis ◽  
Concentration Polarization ◽  
Operating Conditions ◽  
Distinct Advantage ◽  
Membrane Systems ◽  
Cfd Simulations ◽  
Ro Membrane

Empirical correlations for mass transfer coefficient and friction factor are often used in process models for reverse osmosis (RO) membrane systems. These usually involve four dimensionless groups, namely Reynolds number (Re), Sherwood number (Sh), friction factor (f), and Schmidt number (Sc), with the associated coefficients and exponents being obtained by fitting to experimental data. However, the range of geometric and operating conditions covered by the experiments is often limited. In this study, new dimensionless correlations for concentration polarization (CP) modulus and friction factor are presented, which are obtained by dimensional analysis and using simulation data from computational fluid dynamics (CFD). Two-dimensional CFD simulations are performed on three configurations of spacer-filled channels with 76 combinations of operating and geometric conditions for each configuration, covering a broad range of conditions encountered in RO membrane systems. Results obtained with the new correlations are compared with those from existing correlations in the literature. There is good consistency in the predicted CP with mean discrepancies less than 6%, but larger discrepancies for pressure gradient are found among the various friction factor correlations. Furthermore, the new correlations are implemented in a process model with six spiral wound modules in series and the predicted recovery, pressure drop, and specific energy consumption are compared with a reference case obtained by ROSA (Reverse Osmosis System Analysis, The Dow Chemical Company). Differences in predicted recovery and pressure drop are up to 5% and 83%, respectively, highlighting the need for careful selection of correlations when using predictive models in process design. Compared to existing mass transfer correlations, a distinct advantage of our correlations for CP modulus is that they can be directly used to estimate the impact of permeate flux on CP at a membrane surface without having to resort to the film theory.

Supercritical Extraction of Heracleum persicum Plant and Mathematical Modeling

2020 ◽  
Vol 10 (3) ◽  
pp. 298-311
Author(s):  
Mohammad Hossein Bozorgi Pouya ◽  
Bahareh Kamyab Moghadas ◽  
Ali Shokuhi Rad
Keyword(s):  
Mathematical Modeling ◽  
Experimental Data ◽  
Essential Oil ◽  
Supercritical Fluid ◽  
Solid Phase ◽  
Fluid Phase ◽  
Operating Conditions ◽  
Supercritical Extraction ◽  
Model Parameters ◽  
Heracleum Persicum

Background: Supercritical CO2 is the most applicable solvent because of its unique properties such as; high selectivity, non-explosivity, non toxicity, low cost of purchasing and its unique critical points. The solubility of this solvent changed rapidly with only a small change in pressure and temperature especially in pressure. According to literatures, the method of supercritical extraction is the best technology for extracting sensitive constituents. Despite of numerous studies in the literature for extracting essential oil from plants, no studies can be found about this valuable medicinal plant by CO2 supercritical extraction method. Method: In this study, the extraction of main medicinal constituents from Heracleum Persicum and mathematical modeling was done using supercritical carbon dioxide. The experimental data were investigated was analyzed by using gas chromatography (GC) and mass spectrometer chromatography (GC-MS) methods. The model of seed and bed, which includes three parameters of mass transfer, axial dispersion, and effective penetration coefficients, were used for modeling the extraction process. This model was used based on the equilibrium of the fluid phase and solid phase to communicate with the experimental data. Then the obtained yield of supercritical technology was compared with the hydro distillation method. Results: The main extracted constituents of some different varieties of Heracleum by different methods and solvents have been determined. The extracted chemicals by supercritical fluid technology from the seeds of the Heracleum Persicum encompasses hexyl butanoate, octyl 2- methyl butyrate, octylisobutyrate and anethole which are so effective against epilepsy and has the most antibacterial, antiviral and antifungal effects. So supercritical fluid extraction is more selective than the other methods. Conclusion: Extracting of essential oil and mathematical modeling from H. persicum were performed under different operating conditions of temperature, pressure, particle size and solvent flow rate. Experimental and modeling results showed that the operating parameters used in different conditions had a different effect on extraction efficiency and model parameters.

Characterization of seawater reverse osmosis fouled membranes from large scale commercial desalination plant

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Reverse Osmosis ◽  
Large Scale ◽  
Retention Rate ◽  
Local Level ◽  
Microscopic Analysis ◽  
Transmembrane Pressure ◽  
Hydraulic Permeability ◽  
Seawater Reverse Osmosis ◽  
A Chain

The objective of this work is to study the ageing state of a used reverse osmosis (RO) membrane taken in Algeria from the Benisaf Water Company seawater desalination unit. The study consists of an autopsy procedure used to perform a chain of analyses on a membrane sheet. Wear of the membrane is characterized by a degradation of its performance due to a significant increase in hydraulic permeability (25%) and pressure drop as well as a decrease in salt retention (10% to 30%). In most cases the effects of ageing are little or poorly known at the local level and global measurements such as (flux, transmembrane pressure, permeate flow, retention rate, etc.) do not allow characterization. Therefore, a used RO (reverse osmosis) membrane was selected at the site to perform the membrane autopsy tests. These tests make it possible to analyze and identify the cause as well as to understand the links between performance degradation observed at the macroscopic scale and at the scale at which ageing takes place. External and internal visual observations allow seeing the state of degradation. Microscopic analysis of the used membranes surface shows the importance of fouling. In addition, quantification and identification analyses determine a high fouling rate in the used membrane whose foulants is of inorganic and organic nature. Moreover, the analyses proved the presence of a biofilm composed of protein.

Analysis and calculation of the process of low-pressure reverse osmosis during recycling of hygienic water

2019 ◽  
pp. 28-36
Author(s):  
Leonid S. Bobe ◽  
Nikolay A. Salnikov
Keyword(s):  
Mass Transfer ◽  
Reverse Osmosis ◽  
Life Support ◽  
Space Station ◽  
Low Pressure ◽  
Operating Pressure ◽  
Life Support System ◽  
Cleaning Agent ◽  
The Difference ◽  
Pressure Channel

Analysis and calculation have been conducted of the process of low-pressure reverse osmosis in the membrane apparatus of the system for recycling hygiene water for the space station. The paper describes the physics of the reverse osmosis treatment and determines the motive force of the process, which is the difference of effective pressures (operating pressure minus osmotic pressure) in the solution near the surface of the membrane and in the purified water. It is demonstrated that the membrane scrubbing action is accompanied by diffusion outflow of the cleaning agent components away from the membrane. The mass transfer coefficient and the difference of concentrations (and, accordingly, the difference of osmotic pressures) in the boundary layer of the pressure channel can be determined using an extended analogy between mass transfer and heat transfer. A procedure has been proposed and proven in an experiment for calculating the throughput of a reverse osmosis apparatus purifying the hygiene water obtained through the use of a cleaning agent used in sanitation and housekeeping procedures on Earth. Key words: life support system, hygiene water, water processing, low-pressure reverse osmosis, space station.

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