scholarly journals Experimental Investigation of Heat and Mass Transfer in Tubular Membrane Distillation Module for Desalination

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Adnan Al-Hathal Al-Anezi ◽  
Adel O. Sharif ◽  
M. I. Sanduk ◽  
A. R. Khan
Keyword(s):  
Mass Transfer ◽  
Experimental Investigation ◽  
Water Vapor ◽  
Heat And Mass Transfer ◽  
Membrane Distillation ◽  
Water Desalination ◽  
Heat Transfer Analysis ◽  
Operating Parameters ◽  
Permeate Flux ◽  
Tubular Membrane

Membrane distillation is a thermally driven membrane process for seawater desalination and purification at moderate temperatures and pressures. A hydrophobic micro-porous membrane is used in this process, which separates hot and cold water, allowing water vapor to pass through; while restricting the movement of liquid water, due to its hydrophobic nature. This paper provides an experimental investigation of heat and mass transfer in tubular membrane module for water desalination. Different operating parameters have been examined to determine the mass transport mechanism of water vapor. Based on the experimental results, the effects of operating parameters on permeate flux and the heat transfer analysis have been presented and discussed in details.

scholarly journals Molecular Imaging in Therapeutic Efficacy Assessment of Targeted Therapy for Nonsmall Cell Lung Cancer

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Yanni Hu ◽  
Mei Tian ◽  
Hong Zhang
Keyword(s):  
Water Vapor ◽  
Cold Water ◽  
Nonsmall Cell Lung Cancer ◽  
Porous Membrane ◽  
Membrane Distillation ◽  
Water Desalination ◽  
Heat Transfer Analysis ◽  
Operating Parameters ◽  
Permeate Flux ◽  
Pass Through

Membrane distillation is a thermally driven membrane process for seawater desalination and purification at moderate temperatures and pressures. A hydrophobic micro-porous membrane is used in this process, which separates hot and cold water, allowing water vapor to pass through; while restricting the movement of liquid water, due to its hydrophobic nature. This paper provides an experimental investigation of heat and mass transfer in tubular membrane module for water desalination. Different operating parameters have been examined to determine the mass transport mechanism of water vapor. Based on the experimental results, the effects of operating parameters on permeate flux and the heat transfer analysis have been presented and discussed in details.

scholarly journals Theoretical Investigation of Vapor Transport Mechanism Using Tubular Membrane Distillation Module

Membranes ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 560
Author(s):  
Adnan Alhathal Alanezi ◽  
Mohamed Bassyouni ◽  
Shereen M. S. Abdel-Hamid ◽  
Hassn Safi Ahmed ◽  
Mohamed Helmy Abdel-Aziz ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Water Vapor ◽  
Mass Transport ◽  
Flow Rate ◽  
Transport Mechanism ◽  
Membrane Distillation ◽  
Permeate Flux ◽  
Transfer Resistance ◽  
Tubular Membrane ◽  
Feed Temperature

This paper’s primary objective is to examine the vapor delivery mechanism through a tubular membrane distillation (MD) module. Experiments were conducted utilizing a hydrophobic tubular membrane module with a pore size of 0.2 µm. To establish the mass transport mechanism of water vapor, tests were carried out first with pure water as a feed. The permeate flow was then determined using NaCl aqueous feed solutions. Distilled water flux at diverse feed temperatures, feed flow rates, and feed salt concentrations was investigated. The permeate flux improved linearly with rising temperature and flow rate of the feed, however, it declined with feed concentration. Increasing temperature from 40 to 70 °C increased the permeate flux by a factor of 2.2, while increasing the feed flow rate from 60 to 120 L/h increased the permeate flux by a factor ranging from 0.7 to 1.1 depending on feed temperature. Using the Dusty gas model (DGM) the mass transport of water vapor is estimated in the membrane pores. The results showed that the water vapor delivery is controlled by way of the Knudsen molecular diffusion transition mechanism and its version changed into one capable of predicting the permeate fluxes. The mass transfer coefficient calculated and located using the Knudsen molecular transition version agreed properly with the corresponding experimental value. The delivery resistances were affected by working parameters, along with feed temperature, flow rate, and concentration. The mass transfer resistance of the membrane became the predominant controlling step to the MD process.

Heat and mass transfer characteristics in vacuum membrane distillation for water desalination

2018 ◽  
Vol 132 ◽  
pp. 52-62
Author(s):  
Elham El-Zanati ◽  
Maaly Khedr ◽  
Ayman El-Gendi ◽  
Heba Abdallah ◽  
Eman Farg ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Membrane Distillation ◽  
Water Desalination ◽  
Transfer Characteristics ◽  
Vacuum Membrane Distillation

scholarly journals Development of mass and heat transfer coupled model of hollow fiber membrane for salt recovery from brine via osmotic membrane distillation

2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Sher Ahmad ◽  
Gabriela Vollet Marson ◽  
Waheed Ur Rehman ◽  
Mohammad Younas ◽  
Sarah Farrukh ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Heat And Mass Transfer ◽  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Membrane Distillation ◽  
Fiber Membrane ◽  
Salt Recovery ◽  
Osmotic Solution

Abstract Background In this research work, a coupled heat and mass transfer model was developed for salt recovery from concentrated brine water through an osmotic membrane distillation (OMD) process in a hollow fiber membrane contactor (HFMC).The model was built based on the resistance-in-series concept for water transport across the hydrophobic membrane. The model was adopted to incorporate the effects of polarization layers such as temperature and concentration polarization, as well as viscosity changes during concentration. Results The modeling equations were numerically simulated in MATLAB® and were successfully validated with experimental data from literature with a deviation within the range of 1–5%. The model was then applied to study the effects of key process parameters like feed concentrations, osmotic solution concentration, feed, and osmotic solution flow rates and feed temperature on the overall heat and mass transfer coefficient as well as on water transport flux to improve the process efficiency. The mass balance modeling was applied to calculate the membrane area based on the simulated mass transfer coefficient. Finally, a scale-up for the MD process for salt recovery on an industrial scale was proposed. Conclusions This study highlights the effect of key parameters for salt recovery from wastewater using the membrane distillation process. Further, the applicability of the OMD process for salt recovery on large scale was investigated. Sensitivity analysis was performed to identify the key parameters. From the results of this study, it is concluded that the OMD process can be promising in salt recovery from wastewater.

scholarly journals Capillary Polypropylene Membranes for Membrane Distillation

Fibers ◽  
2018 ◽  
Vol 7 (1) ◽  
pp. 1 ◽  
Author(s):  
Marek Gryta
Keyword(s):  
Continuous Process ◽  
Negative Influence ◽  
Membrane Distillation ◽  
Water Desalination ◽  
Porous Membranes ◽  
Surface Porosity ◽  
Permeate Flux ◽  
Thermally Induced

Only nonwetted porous membranes can be used in membrane distillation. The possibility of application in this process the capillary polypropylene membranes manufactured by thermally-induced phase separation was studied. The performance of a few types of membranes available commercially was presented. The resistance of the membranes to wetting was tested in the continuous process of water desalination. These studies were carried out for 1000 h without module cleaning. The presence of scaling layer on the membranes surface was confirmed by Scanning Electron Microscope observations. Both the permeate flux and distillate conductivity were almost not varied after the studied period of time, what indicates that the used membranes maintained their nonwettability, and the negative influence of scaling was limited. The role of surface porosity on the pore wetting and influence of membrane wettability on the quality of the distillate obtained were discussed.

scholarly journals Performance Investigation of O-Ring Vacuum Membrane Distillation Module for Water Desalination

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Adnan Alhathal Alanezi ◽  
H. Abdallah ◽  
E. El-Zanati ◽  
Adnan Ahmad ◽  
Adel O. Sharif
Keyword(s):  
Flow Rate ◽  
Membrane Distillation ◽  
Membrane Module ◽  
Water Desalination ◽  
Feed Flow Rate ◽  
Permeate Flux ◽  
Vacuum Degree ◽  
Flat Sheet ◽  
Vacuum Membrane Distillation ◽  
Feed Temperature

A new O-ring flat sheet membrane module design was used to investigate the performance of Vacuum Membrane Distillation (VMD) for water desalination using two commercial polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) flat sheet hydrophobic membranes. The design of the membrane module proved its applicability for achieving a high heat transfer coefficient of the order of 103 (W/m2 K) and a high Reynolds number (Re). VMD experiments were conducted to measure the heat and mass transfer coefficients within the membrane module. The effects of the process parameters, such as the feed temperature, feed flow rate, vacuum degree, and feed concentration, on the permeate flux have been investigated. The feed temperature, feed flow rate, and vacuum degree play an important role in enhancing the performance of the VMD process; therefore, optimizing all of these parameters is the best way to achieve a high permeate flux. The PTFE membrane showed better performance than the PVDF membrane in VMD desalination. The obtained water flux is relatively high compared to that reported in the literature, reaching 43.8 and 52.6 (kg/m2 h) for PVDF and PTFE, respectively. The salt rejection of NaCl was higher than 99% for both membranes.

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