Investigation of outlet diameter effect on emulsion separation efficiency in rectangular separators

The purpose of the study is to conduct experimental studies of oil -water emulsion separation in a rectangular separator in the range of velocities along the device working area from 1.43 to 2.5 m/s. The efficiency of emulsion separation is determined by an experimental method based on measuring the density of a two-phase liquid, provided that the density of each component of the mixture is previously determined. The authors propose to use a device with U-shaped elements to increase its performance when separating oil-water emulsions. The device under study including two rows of U-shaped elements consists of one complete separation stage. The authors have conducted experimental studies of the device with U-shaped elements on the "oil-water" system, during which the efficiency of emulsion separation was evaluated. It was detemined that the proposed device provides the highest efficiency of emulsion separation of 68% when the diameter of the holes intended for the exit of the heavy phase equals to 2.5 mm in the range of emulsion velocities from 1.43 to 2.5 m/s. The conducted experimental studies will allow to use a turbulence model for calculation in the programs like Ansys Fluent or FlowVision, which will most adequately describe the separation process of similar emulsions. The experiments have proved the possibility of obtaining high values of efficiency. Therefore, the correct selection of technological parameters (average flow rate, concentration) and the size of the characteristic elements of the proposed device will allow to specify the design of a rectangular separator, for example, to calculate the number of stages to achieve the required separation efficiency or to determine the size of the separation elements.

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A cellulose sponge with robust superhydrophilicity and under-water superoleophobicity for highly effective oil/water separation

Green Chemistry ◽

10.1039/c5gc00025d ◽

2015 ◽

Vol 17 (5) ◽

pp. 3093-3099 ◽

Cited By ~ 160

Author(s):

Gang Wang ◽

Yi He ◽

He Wang ◽

Lin Zhang ◽

Quanyao Yu ◽

...

Keyword(s):

Separation Efficiency ◽

Water Separation ◽

Water Emulsion ◽

Cellulose Sponge ◽

Highly Effective ◽

Emulsion Separation ◽

Oil Water Separation ◽

Oil Water

A cellulose sponge with properties of superhydrophilicity and under-water superoleophobicity gives 99.94% separation efficiency in oil–water emulsion separation.

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Mussel-Inspired Fabrication of PDA@PAN Electrospun Nanofibrous Membrane for Oil-in-Water Emulsion Separation

Nanomaterials ◽

10.3390/nano11123434 ◽

2021 ◽

Vol 11 (12) ◽

pp. 3434

Author(s):

Haodong Zhao ◽

Yali He ◽

Zhihua Wang ◽

Yanbao Zhao ◽

Lei Sun

Keyword(s):

Separation Efficiency ◽

Low Cost ◽

Nanofibrous Membrane ◽

Water Separation ◽

Water Emulsion ◽

Oil In Water ◽

Emulsion Separation ◽

Oil Water Separation ◽

Oil Water ◽

Oil In Water Emulsion

Emulsified oily wastewater threatens human health seriously, and traditional technologies are unable to separate emulsion containing small sized oil droplets. Currently, oil–water emulsions are usually separated by special wettability membranes, and researchers are devoted to developing membranes with excellent antifouling performance and high permeability. Herein, a novel, simple and low-cost method has been proposed for the separation of emulsion containing surfactants. Polyacrylonitrile (PAN) nanofibers were prepared via electrospinning and then coated by polydopamine (PDA) by using self-polymerization reactions in aqueous solutions. The morphology, structure and oil-in-water emulsion separation properties of the as-prepared PDA@PAN nanofibrous membrane were tested. The results show that PDA@PAN nanofibrous membrane has superhydrophilicity and almost no adhesion to crude oil in water, which exhibits excellent oil–water separation ability. The permeability and separation efficiency of n-hexane/water emulsion are up to 1570 Lm−2 h−1 bar−1 and 96.1%, respectively. Furthermore, after 10 cycles of separation, the permeability and separation efficiency values do not decrease significantly, indicating its good recycling performance. This research develops a new method for preparing oil–water separation membrane, which can be used for efficient oil-in-water emulsion separation.

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An ultrathin bilayer membrane with asymmetric wettability for pressure responsive oil/water emulsion separation

Journal of Materials Chemistry A ◽

10.1039/c5ta03975d ◽

2015 ◽

Vol 3 (46) ◽

pp. 23477-23482 ◽

Cited By ~ 105

Author(s):

Liang Hu ◽

Shoujian Gao ◽

Yuzhang Zhu ◽

Feng Zhang ◽

Lei Jiang ◽

...

Keyword(s):

Separation Efficiency ◽

Applied Pressure ◽

Bilayer Membrane ◽

Permeation Flux ◽

Bilayer Membranes ◽

Water Emulsion ◽

Emulsion Separation ◽

Oil Water

Superwetting bilayer membranes exhibit ultrahigh permeation flux and separation efficiency for both W/O and O/W emulsion separation by the modulation of the applied pressure.

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Construction of superhydrophilic hierarchical polyacrylonitrile nanofiber membranes by in situ asymmetry engineering for unprecedently ultrafast oil–water emulsion separation

Journal of Materials Chemistry A ◽

10.1039/d0ta03011b ◽

2020 ◽

Vol 8 (33) ◽

pp. 16933-16942 ◽

Cited By ~ 4

Author(s):

XiQuan Cheng ◽

Zekun Sun ◽

Xiaobin Yang ◽

Zhixing Li ◽

Yingjie Zhang ◽

...

Keyword(s):

Recovery Rate ◽

Separation Efficiency ◽

Functional Networks ◽

Water Emulsion ◽

Pore Structures ◽

Emulsion Separation ◽

Nanofiber Membranes ◽

Oil Water ◽

Pan Nanofiber

With multi-hydrophilic functional networks, asymmetric PAN nanofiber membranes with finely tailored pore structures and hydrophilicity are constructed and show high permeance 22 000 L m−2 h−1 bar−1, separation efficiency 99.2% and flux recovery rate 98%.

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Copolyamide–Clay Nanotube Polymer Composite Nanofiber Membranes: Preparation, Characterization and Its Asymmetric Wettability Driven Oil/Water Emulsion Separation towards Sewage Remediation

Polymers ◽

10.3390/polym13213710 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3710

Author(s):

Sneha Bhagyaraj ◽

Patrik Sobolčiak ◽

Mohammad A. Al-Ghouti ◽

Igor Krupa

Keyword(s):

Polymer Composite ◽

Separation Efficiency ◽

Composite Fiber ◽

Halloysite Nanotubes ◽

Wastewater Management ◽

Fiber Membrane ◽

Water Emulsion ◽

Composite Nanofiber ◽

Emulsion Separation ◽

Oil Water

To address the problem of ever-increasing oily wastewater management, due to its directional liquid transport property, membranes with asymmetric wettability can be effectively used for emulsion separation. This study reports the synthesis of electrospun polymer–clay nanocomposite nanofibers, using co-polyamide polymer (COPA) and halloysite nanotubes (HA) as filler. The influence of clay content on the morphological, thermal and dielectric properties of the polymer composite nanofiber was investigated comprehensively to address the material characteristics of the developed system. The surface structure analysis and contact angle measurements of the electrospun composite nanofibers confirms the change in surface roughness and wettability when the fillers are added to the polymer. The porosity of the composite electrospun nanofiber membrane was found to be 85% with an oil adsorption capacity of 97% and water permeability of 6265 L/m2h. Furthermore, the asymmetric wettability-driven oil/water emulsion separation abilities of the as-synthesized membranes shows that the separation efficiency of the composite fiber membrane is 10% improved compared to that of the neat fiber membrane, with improved separation time.

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