Dynamical Modeling of Water Flux in Forward Osmosis with Multistage Operation and Sensitivity Analysis of Model Parameters

To mathematically predict the behavior of a forward osmosis (FO) process for water recovery, a model was constructed using an asymmetric membrane and glucose as a draw solution, allowing an examination of both phenomenological and process aspects. It was found that the proposed model adequately described the significant physicochemical phenomena that occur in the FO system, including forward water flux, internal concentration polarization (ICP), external concentration polarization (ECP), and reverse solute diffusion (RSD). Model parameters, namely the physiochemical properties of the FO membrane and glucose solutions, were estimated on the basis of experimental and existing data. Through batch FO operations with the estimated parameters, the model was verified. In addition, the influences of ECP and ICP on the water flux of the FO system were investigated at different solute concentrations. Water flux simulation results, which exhibited good agreement with the experimental data, confirmed that ICP, ECP, and RSD had a real impact on water flux and thus must be taken into account in the FO process. With the Latin-hypercube—one-factor-at-a-time (LH–OAT) method, the sensitivity index of diffusivity was at its highest, with a value of more than 40%, which means that diffusivity is the most influential parameter for water flux of the FO system, in particular when dealing with a high-salinity solution. Based on the developed model and sensitivity analysis, the simulation results provide insight into how mass transport affects the performance of an FO system.

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Evaluating Fertilizer-Drawn Forward Osmosis Performance in Treating Anaerobic Palm Oil Mill Effluent

Membranes ◽

10.3390/membranes11080566 ◽

2021 ◽

Vol 11 (8) ◽

pp. 566

Author(s):

Ruwaida Abdul Wahid ◽

Wei Lun Ang ◽

Abdul Wahab Mohammad ◽

Daniel James Johnson ◽

Nidal Hilal

Keyword(s):

Palm Oil ◽

Pure Water ◽

Water Flux ◽

Forward Osmosis ◽

Salt Flux ◽

Palm Oil Mill Effluent ◽

Performance Ratio ◽

Water Recovery ◽

Flux Decline ◽

Palm Oil Mill

Fertilizer-drawn forward osmosis (FDFO) is a potential alternative to recover and reuse water and nutrients from agricultural wastewater, such as palm oil mill effluent that consists of 95% water and is rich in nutrients. This study investigated the potential of commercial fertilizers as draw solution (DS) in FDFO to treat anaerobic palm oil mill effluent (An-POME). The process parameters affecting FO were studied and optimized, which were then applied to fertilizer selection based on FO performance and fouling propensity. Six commonly used fertilizers were screened and assessed in terms of pure water flux (Jw) and reverse salt flux (JS). Ammonium sulfate ((NH4)2SO4), mono-ammonium phosphate (MAP), and potassium chloride (KCl) were further evaluated with An-POME. MAP showed the best performance against An-POME, with a high average water flux, low flux decline, the highest performance ratio (PR), and highest water recovery of 5.9% for a 4-h operation. In a 24-h fouling run, the average flux decline and water recovered were 84% and 15%, respectively. Both hydraulic flushing and osmotic backwashing cleaning were able to effectively restore the water flux. The results demonstrated that FDFO using commercial fertilizers has the potential for the treatment of An-POME for water recovery. Nevertheless, further investigation is needed to address challenges such as JS and the dilution factor of DS for direct use of fertigation.

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EVALUATION OF BACTERIAL CELLULOSE-SODIUM ALGINATE FORWARD OSMOSIS MEMBRANE FOR WATER RECOVERY

Jurnal Teknologi ◽

10.11113/jt.v80.12742 ◽

2018 ◽

Vol 80 (3-2) ◽

Author(s):

Ngan T. B. Dang ◽

Liza B. Patacsil ◽

Aileen H. Orbecido ◽

Ramon Christian P. Eusebio ◽

Arnel B. Beltran

Keyword(s):

Contact Angle ◽

Bacterial Cellulose ◽

Sodium Alginate ◽

Water Flux ◽

Forward Osmosis ◽

Composite Membranes ◽

Membrane Thickness ◽

Water Recovery ◽

Sem Images ◽

Salt Rejection

Water resources are very important to sustain life. However, these resources have been subjected to stress due to population growth, economic and industrial growth, pollution and climate change. With these, the recovery of water from sources such as wastewater, dirty water, floodwater and seawater is a sustainable alternative. The potential of recovering water from these sources could be done by utilizing forward osmosis, a membrane process that exploits the natural osmotic pressure gradient between solutions which requires low energy operation. This study evaluated the potential of forward osmosis (FO) composite membranes fabricated from bacterial cellulose (BC) and modified with sodium alginate. The membranes were evaluated for water flux and salt rejection. The effect of alginate concentrations and impregnation temperatures were evaluated using 0.6 M sodium chloride solution as feed and 2 M glucose solution as the draw solution. The membranes were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and Contact Angle Meter (CAM). The use of sodium alginate in BC membrane showed a thicker membrane (38.3 μm to 67.6 μm), denser structure (shown in the SEM images), and more hydrophilic (contact angle ranges from 28.39° to 32.97°) compared to the pristine BC membrane (thickness = 12.8 μm and contact angle = 66.13°). Furthermore, the alginate modification lowered the water flux of the BC membrane from 9.283 L/m2-h (LMH) to value ranging from 2.314 to 4.797 LMH but the improvement in salt rejection was prominent (up to 98.57%).

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Water recovery from sewage using forward osmosis

Water Science & Technology ◽

10.2166/wst.2011.773 ◽

2011 ◽

Vol 64 (7) ◽

pp. 1443-1449 ◽

Cited By ~ 61

Author(s):

Kerusha Lutchmiah ◽

Emile R. Cornelissen ◽

Danny J. H. Harmsen ◽

Jan W. Post ◽

Keith Lampi ◽

...

Keyword(s):

Renewable Energy ◽

Reverse Osmosis ◽

Energy Content ◽

Water Flux ◽

Forward Osmosis ◽

Feed Solution ◽

Water Recovery ◽

High Quality ◽

Mining Project ◽

Quality Water

This research is part of the Sewer Mining project aimed at developing a new technological concept by extracting water from sewage by means of forward osmosis (FO). FO, in combination with a reconcentration system, e.g. reverse osmosis (RO) is used to recover high-quality water. Furthermore, the subsequent concentrated sewage (containing an inherent energy content) can be converted into a renewable energy (RE) source (i.e. biogas). The effectiveness of FO membranes in the recovery of water from sewage has been evaluated. Stable FO water flux values (>4.3 LMH) were obtained with primary effluent (screened, not treated) used as the feed solution. Fouling of the membrane was also induced and further investigated. Accumulated fouling was found to be apparent, but not irreversible. Sewer Mining could lead to a more economical and sustainable treatment of wastewater, facilitating the extraction of water and energy from sewage and changing the way it is perceived: not as waste, but as a resource.

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Sensitivity-guided evaluation of the HBV hydrological model parameterization

Journal of Hydroinformatics ◽

10.2166/hydro.2012.011 ◽

2012 ◽

Vol 15 (3) ◽

pp. 967-990 ◽

Cited By ~ 8

Author(s):

M. B. Zelelew ◽

K. Alfredsen

Keyword(s):

Sensitivity Analysis ◽

Hydrological Model ◽

River Basin Management ◽

Low Flow ◽

Model Parameters ◽

Sensitivity Index ◽

Analysis Method ◽

Flow Conditions ◽

Model Parameterization ◽

Sensitivity Analysis Method

Applying hydrological models for river basin management depends on the availability of the relevant data information to constrain the model residuals. The estimation of reliable parameter values for parameterized models is not guaranteed. Identification of influential model parameters controlling the model response variations either by main or interaction effects is therefore critical for minimizing model parametric dimensions and limiting prediction uncertainty. In this study, the Sobol variance-based sensitivity analysis method was applied to quantify the importance of the HBV conceptual hydrological model parameterization. The analysis was also supplemented by the generalized sensitivity analysis method to assess relative model parameter sensitivities in cases of negative Sobol sensitivity index computations. The study was applied to simulate runoff responses at twelve catchments varying in size. The result showed that varying up to a minimum of four to six influential model parameters for high flow conditions, and up to a minimum of six influential model parameters for low flow conditions can sufficiently capture the catchments' responses characteristics. To the contrary, varying more than nine out of 15 model parameters will not make substantial model performance changes on any of the case studies.

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Strategic Framework for Parameterization of Cell Culture Models

Processes ◽

10.3390/pr7030174 ◽

2019 ◽

Vol 7 (3) ◽

pp. 174

Author(s):

Pavlos Kotidis ◽

Cleo Kontoravdi

Keyword(s):

Experimental Data ◽

Cell Culture ◽

Sensitivity Analysis ◽

Goodness Of Fit ◽

Sampling Methods ◽

Model Parameters ◽

Sensitivity Index ◽

Cho Cell ◽

Culture Models ◽

Cell Culture Models

Global Sensitivity Analysis (GSA) is a technique that numerically evaluates the significance of model parameters with the aim of reducing the number of parameters that need to be estimated accurately from experimental data. In the work presented herein, we explore different methods and criteria in the sensitivity analysis of a recently developed mathematical model to describe Chinese hamster ovary (CHO) cell metabolism in order to establish a strategic, transferable framework for parameterizing mechanistic cell culture models. For that reason, several types of GSA employing different sampling methods (Sobol’, Pseudo-random and Scrambled-Sobol’), parameter deviations (10%, 30% and 50%) and sensitivity index significance thresholds (0.05, 0.1 and 0.2) were examined. The results were evaluated according to the goodness of fit between the simulation results and experimental data from fed-batch CHO cell cultures. Then, the predictive capability of the model was tested against four different feeding experiments. Parameter value deviation levels proved not to have a significant effect on the results of the sensitivity analysis, while the Sobol’ and Scrambled-Sobol’ sampling methods and a 0.1 significance threshold were found to be the optimum settings. The resulting framework was finally used to calibrate the model for another CHO cell line, resulting in a good overall fit. The results of this work set the basis for the use of a single mechanistic metabolic model that can be easily adapted through the proposed sensitivity analysis method to the behavior of different cell lines and therefore minimize the experimental cost of model development.

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Performance of layer-by-layer (LbL) polyelectrolyte forward osmosis membrane for humic acid removal and reverse solute diffusion

Chemical Engineering Research Bulletin ◽

10.3329/cerb.v19i0.33799 ◽

2017 ◽

Vol 19 ◽

pp. 75 ◽

Cited By ~ 1

Author(s):

Suriani Husaini ◽

Mazrul Nizam Abu Seman

Keyword(s):

Humic Acid ◽

Chemical Engineering ◽

Water Flux ◽

Forward Osmosis ◽

Feed Solution ◽

Solute Diffusion ◽

Membrane Properties ◽

Layer By Layer ◽

Engineering Research ◽

Draw Solution

Recent study claimed that forward osmosis (FO) process could handle the fouling problem due it driven force based on natural osmotic pressure. However, researchers observed that FO membrane had problem with reverse solute diffusion (RSD) of draw solution. Therefore, FO membrane properties must be improved either physically or chemically in order to overcome this problem. Among all, surface modification approach has been acknowledged as a best technique to alter the membrane properties without significantly change the bulk membrane properties. In this study, polyelectrolyte FO membrane has been produced through Layer by Layer (LbL) deposition method by using Poly (diallyl-dimethylammoniumchloride), PDADMAC and Poly (sodium 4-styrene-sulfonate), PSS as an active monomers. Humic acid (HA) as part of Natural Organic Matter constituents was used as the feed solution and NaCl as a draw solution. The chemical structure and morphology of the FO membrane were characterized by FTIR and FESEM, respectively. From this study, the highest water flux and humic acid rejection were achieved at 2.5M of draw solution with value of 2.56 L/m².h and 99%, respectively. In general, the water flux increases as the concentration of draw solutions were increased. However, it was observed that reverse salt diffusion (RSD) become worse at higher concentration of draw solution.Chemical Engineering Research Bulletin 19(2017) 75-79

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Simulation of Forward Osmosis Flow in a Two-Dimensional Asymmetric Membrane Channel With Draw Channel Circular Baffle Implementation

Volume 1: Symposia ◽

10.1115/ajkfluids2015-3126 ◽

2015 ◽

Author(s):

James R. L. Koch ◽

Ramesh K. Agarwal

Keyword(s):

Osmotic Pressure ◽

Pressure Loss ◽

Membrane Filtration ◽

Concentration Polarization ◽

Fluid Dynamic ◽

Forward Osmosis ◽

Cross Flow ◽

Cfd Modeling ◽

Asymmetric Membrane ◽

Asymmetric Membranes

Forward Osmosis (FO) driven asymmetric membrane filtration is a developing technology which shows promise for seawater desalination and wastewater treatment. Due to the fact that asymmetric membranes are widely used in conjunction with this technology, internal concentration polarization (ICP), a flow-entrainment effect occurring within such membranes, is a significant if not dominant source of overall osmotic pressure loss across the membrane. Accurate modeling of ICP effects is therefore very critical for accurate Computational Fluid Dynamic (CFD) modeling of asymmetric membranes. A related, dilutive effect known as external concentration polarization (ECP) also develops on both the rejection and draw sides of the membrane, further contributing to osmotic pressure loss. In order to increase the overall water flux, circular spacers can be implemented within the draw channel of FO cross-flow membrane exchange units to decrease the effects of ICP and draw ECP. The drawback of spacer inclusions is an increased pressure loss across the length of the feed channel. The system efficiency gained by the decrease in ECP must therefore be weighed against the energy cost of hydraulically making up lost channel pressure. To model the geometry of a FO cross-flow channel, the open source CFD package OpenFOAM is used. A compressible flow model with explicit boundary conditions is developed to simulate the flux transfer and ICP effects present within an asymmetric membrane when exposed to a NaCl solution. Results are validated by comparison with the numerical data generated by earlier models of asymmetric membranes implemented by other investigators using similar simulation conditions.

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Research on Parameters Indentification of Synthesis Load Model Considering Distribution Network Connection

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.712-715.1343 ◽

2013 ◽

Vol 712-715 ◽

pp. 1343-1346

Author(s):

Guo Ping Shi ◽

Peng Gu

Keyword(s):

Sensitivity Analysis ◽

Power Grid ◽

Computing Time ◽

Distribution Network ◽

Model Parameters ◽

Model Structure ◽

Actual Performance ◽

Load Model ◽

Network Connection ◽

Simulation Results

Synthesis load model considering distribution network connection can simulate actual performance of power grid, however, the model structure is quiet complicated, and distinguished result of parameters is not unique. To solve the above-mentioned problems, this paper proposes a load model parameters identification method based on sensitivity analysis by analysis the structure of synthesis load model with distribution network connection, The simulation results show the model is effective and proper, and the method can reduce computation and save computing time.

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Fabrication of PSS/PDADMAC Polyelectrolyte Membrane via Layer-by-Layer (LbL) Technique for Forward Osmosis (FO) Application

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.797.13 ◽

2019 ◽

Vol 797 ◽

pp. 13-19

Author(s):

Mok Tze How ◽

Mazrul Nizam Abu Seman

Keyword(s):

Deposition Time ◽

Pure Water ◽

Water Flux ◽

Forward Osmosis ◽

Solute Diffusion ◽

Layer By Layer ◽

Styrene Sulfonate ◽

Membrane Performance ◽

Coated Layer ◽

Polyelectrolyte Membrane

In this study, FO membrane was fabricated by Layer-by-Layer (LbL) coating technique using Poly (sodium 4-styrene-sulfonate)(PSS) and Poly (diallyl-dimethylammoniumchloride) (PDADMAC) as the active polyelectrolytes. Different concentrations of polyelectrolytes and deposition time of polyelectrolytes were investigated. The success of the coated layer was confirmed using ATR-FTIR and FESEM images. The membrane performance was determined by water flux and reverse solute diffusion (RSD) using pure water and 1.75M Na2SO4 as feed and draw solution, respectively. It was observed that the highest water flux, 6.76 L/ was recorded at the lowest polyelectrolytes concentration and longer deposition time. Meanwhile, the minimum RSD was achieved by the membrane fabricated at the longest deposition time and highest polyelectrolyte concentration.

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