scholarly journals Biofouling Mitigation Approaches during Water Recovery from Fermented Broth via Forward Osmosis

Membranes ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 307
Author(s):  
Stavros Kalafatakis ◽  
Agata Zarebska ◽  
Lene Lange ◽  
Claus Hélix-Nielsen ◽  
Ioannis V. Skiadas ◽  
...  
Keyword(s):  
Flow Velocity ◽  
Forward Osmosis ◽  
Cross Flow ◽  
Feed Solution ◽  
Mitigation Strategies ◽  
Water Recovery ◽  
Operational Parameters ◽  
Solution Ph ◽  
Sustainable Solutions ◽  
Cross Flow Velocity

Forward Osmosis (FO) is a promising technology that can offer sustainable solutions in the biorefinery wastewater and desalination fields, via low energy water recovery. However, microbial biomass and organic matter accumulation on membrane surfaces can hinder the water recovery and potentially lead to total membrane blockage. Biofouling development is a rather complex process and can be affected by several factors such as nutrient availability, chemical composition of the solutions, and hydrodynamic conditions. Therefore, operational parameters like cross-flow velocity and pH of the filtration solution have been proposed as effective biofouling mitigation strategies. Nevertheless, most of the studies have been conducted with the use of rather simple solutions. As a result, biofouling mitigation practices based on such studies might not be as effective when applying complex industrial mixtures. In the present study, the effect of cross-flow velocity, pH, and cell concentration of the feed solution was investigated, with the use of complex solutions during FO separation. Specifically, fermentation effluent and crude glycerol were used as a feed and draw solution, respectively, with the purpose of recirculating water by using FO alone. The effect of the abovementioned parameters on (i) ATP accumulation, (ii) organic foulant deposition, (iii) total water recovery, (iv) reverse glycerol flux, and (v) process butanol rejection has been studied. The main findings of the present study suggest that significant reduction of biofouling can be achieved as a combined effect of high-cross flow velocity and low feed solution pH. Furthermore, cell removal from the feed solution prior filtration may further assist the reduction of membrane blockage. These results may shed light on the challenging, but promising field of FO process dealing with complex industrial solutions.

scholarly journals Behaviour of Aquaporin Forward Osmosis Flat Sheet Membranes during the Concentration of Calcium-Containing Liquids

Membranes ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 108
Author(s):  
Alibek Omir ◽  
Aliya Satayeva ◽  
Aigerim Chinakulova ◽  
Arailym Kamal ◽  
Jong Kim ◽  
...  
Keyword(s):  
Flow Velocity ◽  
Saturation Index ◽  
Membrane Surface ◽  
Water Flux ◽  
Forward Osmosis ◽  
Cross Flow ◽  
Calcium Sulphate ◽  
Attenuated Total Reflection ◽  
Flat Sheet ◽  
Cross Flow Velocity

This study aims to examine the scaling and performance of flat sheet aquaporin FO membranes in the presence of calcium salts. Experiments showed that the application of calcium sulphate (CaSO4) resulted in an 8–78% decline in the water flux. An increase in the cross-flow velocity from 3 to 12 cm/s reduced the decline in the flux by 16%. The deposition of salt crystals on the membrane surface led to the alteration in the membrane’s intrinsic properties. Microscopy, attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, and X-Ray fluorescence (XRF) analyses confirmed measurements of the zeta potential and contact angle. The use of a three-salt mixture yielded severe scaling as compared with the application of calcium sulphate dehydrate (CaSO4 × 2H2O), i.e., a result of two different crystallisation mechanisms. We found that the amount of sodium chloride (NaCl), saturation index, cross-flow velocity, and flow regime all play an important role in the scaling of aquaporin FO flat sheet membranes.

scholarly journals Forward Osmosis: Temperature Effects By Using Pome as Feed Solution

2015 ◽  
Vol 15 (1) ◽  
pp. 31 ◽  
Author(s):  
Hanizah Arifin ◽  
Thomas S.Y. Choong ◽  
Chan Kam Rong ◽  
Fakhru'l Al-Razi Ahmadun ◽  
Luqman Chuah Abdullah
Keyword(s):  
Water Flux ◽  
Forward Osmosis ◽  
Cross Flow ◽  
Feed Solution ◽  
Water Fluxes ◽  
Energy Applications ◽  
Draw Solution ◽  
Influence Of Temperature On ◽  
Cross Flow Velocity ◽  
Higher Temperature

Forward osmosis (FO) has recently been considered as one of the promising technologies for low energy applications. Factors that influence FO performance are draw solution, types of membrane, membrane orientation, cross flow velocity, module configuration and temperature effect. In this study, the influence of temperature on the performance of FO process has been studied in terms of water flux by using raw POME as feed solution. A higher temperature creates a higher water fluxes at various draw solution concentrations. Percentages of water flux increments for raw POME are between 7% to 9% from 25ºC to 35ºC and 32% to 75% from 25ºC to 45ºC.

scholarly journals Forward osmosis membrane fouling and cleaning for wastewater reuse

2016 ◽  
Vol 7 (2) ◽  
pp. 111-120 ◽  
Author(s):  
Youngbeom Yu ◽  
Seockheon Lee ◽  
Sung Kyu Maeng
Keyword(s):  
Activated Sludge ◽  
Flow Velocity ◽  
Membrane Fouling ◽  
Suspended Solids ◽  
Wastewater Reuse ◽  
Forward Osmosis ◽  
Cross Flow ◽  
Short Period ◽  
Cross Flow Velocity ◽  
Cleaning Methods

Membrane fouling properties and different physical cleaning methods for forward osmosis (FO) and reverse osmosis (RO) laboratory-scale filtration systems were investigated. The membrane fouling, with respect to flux reduction, was lower in FO than in RO when testing an activated sludge effluent. Cross-flow velocity, air-scouring, osmotic backwashing and effect of a spacer were compared to determine the most effective cleaning method for FO. After a long period of fouling with activated sludge, the flux was fully recovered in a short period of osmotic backwashing compared with cleaning by changing cross-flow velocity and air-scouring. In this study, the osmotic backwashing was found to be the most efficient way to clean the FO membrane. The amount of RNA recovered from FO membranes was about twice that for RO membranes; biofouling could be more significant in FO than in RO. However, the membrane fouling in FO was lower than that in RO. The spacer increased the flux in FO with activated sludge liquor suspended solids of 2,500 mg/L, and there were effects of spacer on performance of FO–MBR membrane fouling. However, further studies are required to determine how the spacer geometry influences on the performance of the FO membrane.

Significance of Lorentz Force and Thermoelectric on the Flow of 29 nm CuO–Water Nanofluid on an Upper Horizontal Surface of a Paraboloid of Revolution

2018 ◽  
Vol 141 (2) ◽  
Author(s):  
I. L. Animasaun ◽  
B. Mahanthesh ◽  
A. O. Jagun ◽  
T. D. Bankole ◽  
R. Sivaraj ◽  
...  
Keyword(s):  
Flow Velocity ◽  
Numerical Solutions ◽  
Volume Fraction ◽  
Cross Flow ◽  
Horizontal Surface ◽  
Integration Scheme ◽  
Flowing Fluid ◽  
Paraboloid Of Revolution ◽  
Hall Parameter ◽  
Cross Flow Velocity

Combination of electric and magnetic forces on charged molecules of flowing fluid in the presence of a significant electromagnetic fields on surfaces with a nonuniform thickness (as in the case of upper pointed surface of an aircraft and bonnet of a car which are examples of upper horizontal surfaces of a paraboloid of revolution—uhspr) is inevitable. In this study, the influence of imposed magnetic field and Hall effects on the flow of 29 nm CuO–water nanofluid over such object is presented. Suitable similarity variables were employed to nondimensionalize and parameterize the dimensional governing equation. The numerical solutions of the corresponding boundary value problem were obtained using Runge–Kutta fourth-order integration scheme along with shooting technique. The domain of cross-flow velocity can be highly suppressed when the magnitude of imposed magnetic strength and that of Hall parameter are large. A significant increase in the cross-flow velocity gradient near an upper horizontal surface of the paraboloid of revolution is guaranteed with an increase in the Hall parameter. Enhancement of temperature distribution across the flow is apparent due to an increase in the volume fraction.

scholarly journals Module-Scale Simulation of Forward Osmosis Module-Part A: Plate-and-Frame

2016 ◽  
Vol 1 (2) ◽  
pp. 249 ◽  
Author(s):  
Muhammad Roil Bilad
Keyword(s):  
Forward Osmosis ◽  
Mass Conservation ◽  
Feed Solution ◽  
Transfer Model ◽  
Operational Parameters ◽  
Permeable Membrane ◽  
Promising Alternative ◽  
A Value ◽  
Scale Optimization ◽  
Module Performance

In forward osmosis (FO), a semi-permeable membrane separates a concentrated draw and a diluted feed solution. FO has emerges as a promising alternative for various applications. To support further development of FO process, a larger scale optimization is required to accurately envisage the most critical factors to be explored. In this study, we applied a mass-transfer model coupled with the mass conservation and area discretization to simulate the performance of plate-and-frame FO modules (10 sheets of 1x1m). Effects of numerous parameters were simulated: modes, flow orientations (co-, counter- and cross-currents), spacers and spacer properties, membrane parameters and operational parameters. Results show that counter-current flow orientation offers the highest flux with minimum spatial distribution. Module performance can be improved by developing FO membrane through reducing membrane structural (S) parameter and increasing water permeability (A): increasing A-value only significant at low S-value, and vice versa (i.e., for A-value of 1 LMH/atm, S-value must be below 50 µm). Furthermore, inclusion of spacer in the flow channel slightly increases the flux (merely up to 2%). Module performance can also be enhanced by increasing feed flow rate, lowering solute in the feed and increasing solute in the draw solution.

A Family of Hodograph Models for the Cross Flow Velocity Component of Three-Dimensional Turbulent Boundary Layers

1972 ◽  
Vol 94 (2) ◽  
pp. 321-329 ◽  
Author(s):  
J. R. Shanebrook ◽  
D. E. Hatch
Keyword(s):  
Flow Velocity ◽  
Boundary Layers ◽  
Velocity Component ◽  
Three Dimensional ◽  
Cross Flow ◽  
Turbulent Boundary Layers ◽  
Flow Profiles ◽  
Rectangular Channels ◽  
Cross Flow Velocity ◽  
The Cross

A family of hodograph models for the cross flow velocity component of three-dimensional, turbulent boundary layers is presented. The principal advantage of this family is its flexibility which allows a wide variety of possible shapes for the hodograph. An integral method based on this family is developed and applied to data obtained in curved, rectangular channels. For the cases treated, the method gives acceptable results for cross flow profiles with and without flow reversal. Suggestions for refining the method are given.

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