Numerical simulation of oil-water separation process in disc separator

As most of the light and easy oil fields have been produced or are nearing their end-life, the emulsion stability is enhanced and water cut is increasing in produced fluid which have brought challenges to oil–water separation in onshore and offshore production trains. The conventional solution to these challenges includes a combination of higher chemical dosages, larger vessels and more separation stages, which often demands increased energy consumption, higher operating costs and larger space for the production facility. It is not always feasible to address the issues by conventional means, especially for the separation process on offshore platforms. Electrostatic coalescence is an effective method to achieve demulsification and accelerate the oil–water separation process. In this paper, a novel compact electrostatic coalescer with helical electrodes was developed and its performance on treatment of water-in-oil emulsions was investigated by experiments. Focused beam reflectance measurement (FBRM) was used to make real-time online measurements of water droplet sizes in the emulsion. The average water droplet diameters and number of droplets within a certain size range are set as indicators for evaluating the effect of coalescence. We investigated the effect of electric field strength, frequency, water content and fluid velocity on the performance of coalescence. The experimental results showed that increasing the electric field strength could obviously contribute to the growth of small water droplets and coalescence. The extreme value of electric field strength achieved in the high-frequency electric field was much higher than that in the power-frequency (50 Hz) electric field, which can better promote the growth of water droplets. The initial average diameters of water droplets increase with higher water content. The rate of increment in the electric field was also increased. Its performance was compared with that of the plate electrodes to further verify the advantages of enhancing electrostatic coalescence and demulsification with helical electrodes. The research results can provide guidance for the optimization and performance improvement of a compact electrocoalescer.

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An oil/water separation nanofibrous membrane with a 3-D structure from the blending of PES and SPEEK

High Performance Polymers ◽

10.1177/0954008318825297 ◽

2019 ◽

Vol 31 (5) ◽

pp. 538-547 ◽

Cited By ~ 6

Author(s):

Qiong Du ◽

Zheng Chen ◽

Xiangyu Jiang ◽

Jinhui Pang ◽

Zhenhua Jiang ◽

...

Keyword(s):

Mechanical Strength ◽

Separation Process ◽

Nanofibrous Membrane ◽

Water Separation ◽

Water Emulsion ◽

High Mechanical Strength ◽

Good Thermal Stability ◽

Oil In Water ◽

Oil Water Separation ◽

Oil Water

A new nanofibrous membrane (NFM) was prepared by blending polyethersulfone (PES) and sulfonated poly(ether ether ketone) (SPEEK) via electrospinning. The membrane exhibits good thermal stability and high mechanical strength. The hydrophilicity of the membrane could be controlled by adjusting the mass ratio of PES to SPEEK. PES acts as the backbone fiber and provides high mechanical strength, while SPEEK provides hydrophilic functional groups due to the strong hydrophilicity of the sulfonic group. The test results show that the composite NFM integrates the advantages of the two polymers. Simple adjustment of the weight ratios of the two polymers can enable an adjustable flux so that the membrane can be used for different kinds of oil/water separation. The results show that NFMs can not only separate immiscible oil/water systems but also separate oil-in-water emulsions. The immiscible oil/water separation process was driven only by gravity and had a high flux of 1119.63 Lm−2 h−1. This separation process conserves energy, which is beneficial for environmental protection. The separation flux of the oil-in-water emulsion was 758.71 Lm−2 h−1 bar−1 based on measurements under different pressures, and the separation purity total organic carbon was below 50 ppm. This work indicates that a membrane comprised of PES and SPEEK has excellent performance and can be used in different fields.

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Potential Efficient Separation of Oil from Bilgewater and Kitchen Wastewater by Fractional Freezing Process

Crystals ◽

10.3390/cryst11060685 ◽

2021 ◽

Vol 11 (6) ◽

pp. 685

Author(s):

Siti Nor Adibah Mustapha ◽

Nurul Aini Amran ◽

Intan Lyana Roslan ◽

Rubini Chandra Segaran ◽

Shafirah Samsuri

Keyword(s):

Crystal Growth ◽

Separation Process ◽

Process Efficiency ◽

Coolant Temperature ◽

Oily Wastewater ◽

Water Separation ◽

Efficient Separation ◽

Stirring Rate ◽

Oil Water Separation ◽

Oil Water

Oily wastewater discharge to water bodies can have many negative consequences, especially on the marine ecological environment. Although there are numerous techniques for treating oily wastewater, this paper aims to introduce and evaluate the potential of the fractional freezing (FF) process as a new oil–water separation technique to overcome the several weaknesses found in the conventional oil–water separation methods. FF separates two liquid compounds based on their freezing point difference. In this study, two oily wastewater samples were used: oily bilgewater and oily kitchen wastewater. The effects of coolant temperature, freezing time, and stirring rate on the FF process efficiency were studied, and the significance of the data was supported by statistical analysis. The results show that a low coolant temperature is essential for allowing crystal nucleation formation and inducing crystal growth for an efficient separation process. However, the higher crystal growth rate that occurs at an even lower temperature might entrap the impurities inside the growing crystal. Consequently, continuing the crystallization for a longer time may yield a less efficient separation process. Furthermore, a too high stirring rate will rupture the solid formation, hence reducing the process efficiency. The final values of oil/grease and free fatty acids (FFA) obtained after the FF process of both samples were found to comply with the standard permitted by the International Maritime Organization (IMO) and Palm Oil Refiners Association of Malaysia (PORAM). Moreover, the p-values obtained for both of the above-mentioned samples were below 0.05 for all experiments. It can be concluded that this method has the potential to separate oil from the oily bilgewater and kitchen wastewater.

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Superhydrophobic Treatment of Polyurethane Sponge and Its Application in Oil-water Separation

Asian Journal of Chemical Sciences ◽

10.9734/ajocs/2019/v6i419004 ◽

2019 ◽

pp. 1-9

Author(s):

Fan Li ◽

Wenhong Wang ◽

Jie Wang ◽

Yangfeng Peng

Keyword(s):

Copper Chloride ◽

Separation Process ◽

Separation Performance ◽

Water Separation ◽

Carbon Chains ◽

Oil Water Separation ◽

Polyurethane Sponge ◽

Oil Water ◽

Special Case ◽

High Repeatability

The superhydrophobicity of the polyurethane sponge was realized by attaching the complex of copper and mercaptan on the outer surface of the polyurethane sponge. As a special case, the complex of 1-dodecanthiol and copper chloride was intensively investigated in this study, with emphasis on the influences of concentration, temperature and residence time on the reaction. SEM and EDS were used to analyze the surface structure and elemental composition of the sponge. The superhydrophobicity of the sponge are contributed by the rough treatment on sponge surface. It is found that a large number of long carbon chains appear on the surface reduces the surface energy. The wettability of the surface was determined by a contact angle meter. The material demonstrates great oil-water separation performance and high repeatability in superhydrophobicity during the the separation process of oil and water before first 39 times.

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