Journal of Applied Science and Engineering

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Mohammad Assaleh1This email address is being protected from spambots. You need JavaScript enabled to view it., George G. Chase1, Tinoush Dinn2, and Martin Panchula2

1Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, OH 44325, USA.

2BASF Corporation, 23800 Mercantile Rd, Beachwood, OH 44122, USA.



Received: March 1, 2024
Accepted: April 22, 2024
Publication Date: June 11, 2024

 Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

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Water separation from diesel fuel is critical for automotive performance and longevity due to its adverse effects on engines. Conventional methods like gravity settling fail with emulsified water due to small droplet size and stable interfaces. Electric field devices, such as electrocoalescers, are commonly employed to coalesce water drops for easier separation. However, these typically require high voltages and large gap distances between electrodes, with coalescence primarily occurring within the bulk fluid. Significant coalescence on electrode surfaces can be achieved through electrowetting, particularly when drops contact both electrodes, necessitating close electrode proximity. This study presents experimental water-ULSD dispersion separation using an electrowet coalescer device (EWC) consisting of two porous wire mesh electrodes with a small gap. Compact and operated at voltages below 250V, the EWC’s performance was evaluated by varying design and operating parameters. Under optimal conditions, it increased average water drop size from 50 to over 1600 microns, and when integrated with a setting tank, improved gravity separation efficiency from 6% to 95%.

Keywords: Coalescence, Electrowetting, Water-diesel emulsion, Gravitational separation

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