Influence of humic acid on the long-term performance of direct contact membrane distillation

In this study, the influence of humic acid on the treatment of coalbed methane water by direct contact membrane distillation was examined with bench-scale test unit. During short-term distillation (1000 min), high level of humic acid above 50 ppm resulted in significant decrease in permeate flux, while low level of humic acid (∼2 ppm) had little influence on the flux. For the long-term distillation (5000 min), the flux decline began at 3400 min in the presence of 5 ppm humic acid and 5 mM Ca2+, and decreased to ∼40% of initial flux at 5000 min. The spectroscopic analysis of the membrane used revealed that the surface was covered by hydrophilic layers mainly composed of calcite. The membrane fouling effect of humic acid became more significant in the presence of Ca2+ due to more facile calcite formation on the membrane surface. It was demonstrated that humic acid enhanced CaCO3 deposition on the membrane surfaces, thereby expediting the scaling phenomenon.

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Organic Fouling Impact in a Direct Contact Membrane Distillation System Treating Wastewater: Experimental Observations and Modeling Approach

Membranes ◽

10.3390/membranes11070493 ◽

2021 ◽

Vol 11 (7) ◽

pp. 493

Author(s):

Amine Charfi ◽

Fida Tibi ◽

Jeonghwan Kim ◽

Jin Hur ◽

Jinwoo Cho

Keyword(s):

Particle Size ◽

Membrane Fouling ◽

Direct Contact ◽

Feed Solution ◽

Membrane Distillation ◽

Mixed Solution ◽

Permeate Flux ◽

Direct Contact Membrane Distillation ◽

Organic Fouling ◽

Specific Cake Resistance

This study aims to investigate the effect of operational conditions on organic fouling occurring in a direct contact membrane distillation (DCMD) system used to treat wastewater. A mixed solution of sodium alginate (SA) and bovine serum albumin (BSA) was used as a feed solution to simulate polysaccharides and proteins, respectively, assumed as the main organic foulants. The permeate flux was observed at two feed temperatures 35 and 50 °C, as well as three feed solution pH 4, 6, and 8. Higher permeate flux was observed for higher feed temperature, which allows higher vapor pressure. At higher pH, a smaller particle size was detected with lower permeate flux. A mathematical model based on mass balance was developed to simulate permeate flux with time by assuming (i) the cake formation controlled by attachment and detachment of foulant materials and (ii) the increase in specific cake resistance, the function of the cake porosity, as the main mechanisms controlling membrane fouling to investigate the fouling mechanism responsible of permeate flux decline. The model fitted well with the experimental data with R2 superior to 0.9. High specific cake resistance fostered by small particle size would be responsible for the low permeate flux observed at pH 8.

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Fluoride removal from brackish groundwater by direct contact membrane distillation

Water Science & Technology ◽

10.2166/wst.2010.878 ◽

2010 ◽

Vol 61 (12) ◽

pp. 3178-3187 ◽

Cited By ~ 6

Author(s):

D. Y. Hou ◽

J. Wang ◽

B. Q. Wang ◽

Z. K. Luan ◽

X. C. Sun ◽

...

Keyword(s):

Concentration Factor ◽

Direct Contact ◽

Polyvinylidene Fluoride ◽

Membrane Surface ◽

Membrane Distillation ◽

Rapid Decline ◽

Fluoride Removal ◽

Permeate Flux ◽

Direct Contact Membrane Distillation ◽

Module Efficiency

The direct contact membrane distillation (DCMD) applied for fluoride removal from brackish groundwater is presented. The self-prepared polyvinylidene fluoride membrane exhibited high rejection of inorganic salt solutes and a maximum permeate flux 35.6 kgm−2 h−1 was obtained. The feed concentration had no marked impact on the permeate flux and the rejection of fluoride. The precipitation of CaCO3 would clog the hollow fiber inlets and foul the membrane surface with the increase of concentration factor when natural groundwater was used directly as the feed, which resulted in a rapid decline of the module efficiency. This phenomenon was diminished by acidification of the feed. The experimental results showed that the permeate flux and the quality of obtained distillate kept stable before concentration factor reached 5.0 with the acidified groundwater as feed. The membrane module efficiency began to decline gradually when the feed continued to be concentrated, which can be mainly attributed to the formation of CaF2 deposits on the membrane surface. Finally, a 300 h continuous fluoride removal experiment on acidified groundwater was carried out with concentration factor at 4.0, the permeate flux kept stable and the permeate fluoride was not detected.

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Enhanced Performance of Carbon Nanotube Immobilized Membrane for the Treatment of High Salinity Produced Water via Direct Contact Membrane Distillation

Membranes ◽

10.3390/membranes10110325 ◽

2020 ◽

Vol 10 (11) ◽

pp. 325 ◽

Cited By ~ 1

Author(s):

Madihah Saud Humoud ◽

Sagar Roy ◽

Somenath Mitra

Keyword(s):

Carbon Nanotube ◽

Membrane Fouling ◽

Direct Contact ◽

Produced Water ◽

High Salinity ◽

Membrane Surface ◽

Membrane Distillation ◽

Vapor Flux ◽

Ptfe Membrane ◽

Direct Contact Membrane Distillation

Membrane distillation (MD) is a promising desalination technology for the treatment of high salinity water. Here, we investigated the fouling characteristics of produced water obtained from hydraulic fracturing by implementing a carbon nanotube immobilized membrane (CNIM) via direct contact membrane distillation. The CNIM exhibited enhanced water vapor flux and antifouling characteristics compared to the pristine membrane. The normalized flux decline with the polytetrafluoroethylene (PTFE) membrane after 7 h of operation was found to be 18.2% more than the CNIM. The addition of 1-Hydroxy Ethylidene-1, 1-Diphosphonic acid (HEDP) antiscalant was found to be effective in reducing the membrane fouling. The salt deposition on the membrane surface was 77% less in the CNIM, which was further reduced with the addition of HEDP in the feed by up to 135.4% in comparison with the PTFE membrane. The presence of carbon nanotubes (CNTs) on the membrane surface also facilitated the regenerability of the membrane. The results indicated that the CNIM regained 90.9% of its initial water flux after washing, whereas the unmodified PTFE only regained 81.1% of its initial flux after five days of operation.

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Desalination of brackish groundwater by direct contact membrane distillation

Water Science & Technology ◽

10.2166/wst.2010.110 ◽

2010 ◽

Vol 61 (8) ◽

pp. 2013-2020 ◽

Cited By ~ 7

Author(s):

D. Y. Hou ◽

J. Wang ◽

D. Qu ◽

Z. K. Luan ◽

C. W. Zhao ◽

...

Keyword(s):

Direct Contact ◽

Polyvinylidene Fluoride ◽

Membrane Surface ◽

Negative Influence ◽

Membrane Distillation ◽

Rapid Decline ◽

Water Recovery ◽

Permeate Flux ◽

Feed Concentration ◽

Direct Contact Membrane Distillation

The direct contact membrane distillation (DCMD) applied for desalination of brackish groundwater with self-made polyvinylidene fluoride (PVDF) membranes was presented in the paper. The PVDF membrane exhibited high rejection of non-volatile inorganic salt solutes and a maximum permeate flux 24.5 kg m−2 h−1 was obtained with feed temperature at 70°C. The DCMD experimental results indicated that the feed concentration had no significant influence on the permeate flux and the rejection of solute. When natural groundwater was used directly as the feed, the precipitation of CaCO3 would be formed and clog the hollow fibre inlets with gradual concentration of the feed, which resulted in a rapid decline of the module efficiency. The negative influence of scaling could be eliminated by acidification of the feed. Finally, a 250 h DCMD continuous desalination experiment of acidified groundwater with the concentration factor at constant 4.0 was carried out. The permeate flux kept stable and the permeate conductivity was less than 7.0 μS cm−1 during this process. Furthermore, there was no deposit observed on the membrane surface. All of these demonstrated that DCMD could be efficiently used for production of high-quality potable water from brackish groundwater with water recovery as high as 75%.

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Tannic acid induced membrane surface modification to increase efficiency of direct contact membrane distillation for desalination of the bioreactor effluent of a bioplastic-producing haloarchaeal bioprocess

Materials Today Proceedings ◽

10.1016/j.matpr.2021.02.754 ◽

2021 ◽

Author(s):

Arnab Banerjee ◽

Joydeep Mukherjee

Keyword(s):

Surface Modification ◽

Tannic Acid ◽

Direct Contact ◽

Membrane Surface ◽

Membrane Distillation ◽

Induced Membrane ◽

Direct Contact Membrane Distillation ◽

Increase Efficiency

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Effects of pollutants in alkali/surfactant/polymer (ASP) flooding oilfield wastewater on membrane fouling in direct contact membrane distillation by response surface methodology

Chemosphere ◽

10.1016/j.chemosphere.2021.131130 ◽

2021 ◽

pp. 131130

Author(s):

Xiaoju Yan ◽

Guodong Wang ◽

Cong Ma ◽

Junyu Li ◽

Shirong Cheng ◽

...

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Membrane Fouling ◽

Direct Contact ◽

Membrane Distillation ◽

Asp Flooding ◽

Direct Contact Membrane Distillation

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Direct contact membrane distillation of humic acid solutions

Journal of Membrane Science ◽

10.1016/j.memsci.2004.04.018 ◽

2004 ◽

Vol 240 (1-2) ◽

pp. 123-128 ◽

Cited By ~ 80

Author(s):

M KHAYET

Keyword(s):

Humic Acid ◽

Direct Contact ◽

Membrane Distillation ◽

Acid Solutions ◽

Direct Contact Membrane Distillation

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The role of membrane surface energy on direct contact membrane distillation performance

Desalination ◽

10.1016/j.desal.2012.07.012 ◽

2013 ◽

Vol 323 ◽

pp. 22-30 ◽

Cited By ~ 42

Author(s):

Ludovic F. Dumée ◽

Stephen Gray ◽

Mikel Duke ◽

Kallista Sears ◽

Jürg Schütz ◽

...

Keyword(s):

Surface Energy ◽

Direct Contact ◽

Membrane Surface ◽

Membrane Distillation ◽

Direct Contact Membrane Distillation

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Chemical pretreatment of feed water for membrane distillation

Chemical Papers ◽

10.2478/s11696-007-0085-5 ◽

2008 ◽

Vol 62 (1) ◽

Cited By ~ 7

Author(s):

Marek Gryta

Keyword(s):

Membrane Fouling ◽

Membrane Surface ◽

Membrane Distillation ◽

Feed Water ◽

Chemical Pretreatment ◽

Permeate Flux ◽

Membrane Scaling ◽

Water Pretreatment ◽

Energy Dispersion Spectrometry ◽

Process Operation

AbstractMembrane distillation was used to produce demineralized water from ground water. The influence of feed water pretreatment carried out in a contact clarifier (softening with Ca(OH)2 and coagulation with FeSO4 · 7H2O) followed by filtration, on the process effectiveness was evaluated. It was found that the chemical pretreatment decreased the membrane fouling; however, the degree of water purification was insufficient because precipitation of small amounts of deposit on the membrane surface during the process operation was still observed. The permeate flux was gradually decreasing as a result of scaling. The morphology and composition of the fouling layer were studied using scanning electron microscopy coupled with energy dispersion spectrometry. The presence of significant amounts of silica, apart from calcium and magnesium, was determined in the formed deposit. The removal of foulants by heterogeneous crystallization performed inside the filter (70 mesh), assembled directly at the module inlet, was found to be a solution preventing the membrane scaling.

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