Long-Term Performance of Ultrafiltration Membranes: Corrosion Fouling Aspect

Abstract

The past decade has seen a rise in the importance of the ultrafiltration (UF) technique in the separation of various complex solutions. However, the fouling phenomenon is the main limitation to faster process development. To the best of the authors’ knowledge, the present paper is the first to aim to identify the role of corrosion fouling in long-term UF. For this purpose, polyvinylidene fluoride (PVDF) and polyethersulfone (PES) membranes were used. The investigations were carried out with the use of both pilot-scale and laboratory-scale units. Results obtained in the present study have clearly demonstrated that the oil concentration has a significant impact on the process performance. Indeed, it has been noted that a reduction in oil concentration from 160 to 100 mg/L resulted in an increase in the PVDF membrane flux from 57 to 77 L/m2h. In addition, it has been shown that the feed temperature has a significant influence on the UF performance. Importantly, it has been shown that corrosion fouling is of vital importance in UF membranes. Indeed, corrosion products such as iron oxides contaminated the membrane surface leading to an irreversible decrease in the UF process performance. In addition, it has been found that repeating the chemical cleaning of the membrane units significantly reduced the intensity of the fouling phenomenon. However, the complete elimination of its effects was not achieved. Therefore, it has been indicated that cleaning agents recommended by membrane manufacturers do not remove corrosion products deposited on the membrane surface. Undoubtedly, the obtained results can be used in the design of UF units leading to the extension of membrane installation lifetime.

Carwash Oily Wastewater Separated by Ultrafiltration

“…The deposit layer on the membrane surface usually improves the separation properties of the UF process [25]. It has been shown that not only the pollutants removed from cars but also the components of the liquids used to wash them cause the fouling phenomenon [28]. It is worth noting that waxes used to polish the car body can also be deposited on the membranes.…”

“…To wash the membranes, a solution of Insect agents was used, which is used in car washes to remove insects. These agents, similar to P3 Ultrasil 11, contain NaOH, EDTA tetrasodium salt, and surfactants [26][27][28]. Its advantage is that, unlike commercial agents used for membrane washing, it is approved for use in car washes.…”

Investigation of Different Pre-Treatment Techniques and 3D Printed Turbulence Promoter to Mitigate Membrane Fouling in Dairy Wastewater Module

“…However, membrane fouling remains a Materials 2023, 16, 3117 2 of 15 major challenge in the application of membrane-based technologies for dairy wastewater treatment [8]. Membrane fouling reduces process performance, shortens membrane lifespan, and increases operational costs [9][10][11][12][13][14].…”