An investigation of the filtration performance and mechanism of oil-solid mixed particles on filter materials with different wettability

• Published in: Separation and purification technology Vol. 349; p. 127903
• Main Authors: Tian, Xinjiao, Wei, Hao, Wang, Wenying, Huang, Yixiang, Wang, Hongxiang, Pan, Jiefeng, Wang, Rui, Li, Zhenming
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 03.12.2024
• Subjects: Dust cake filtration; Membrane plugging; Oil-solid mixed particles; Particle deposition; Wettability; Dust cake filtration; Particle deposition; Membrane plugging; Wettability; Oil-solid mixed particles
• ISSN: 1383-5866
• DOI: 10.1016/j.seppur.2024.127903

•The loading behavior of oil-solid mixed particles on the filter material could be classified into two main categories: surface loading and membrane plugging.•The DHC of filter material exhibited a trend of “first increased significantly then dropped dramatically and finally increased” with the oil content increased.•The oleophobic filter material showed superior filtration performance compared to other filter materials with varying wettabilty under the conditions of 25% and 50% oil content.•The superoleophilic filter material displayed superior filtration performance compared to other filter materials with varying wettabilty in the case of 75% and 100% oil content. In the process of air filtration, filter materials may encounter oil-solid mixed particles from various sources such as industry and household, and the influence of filter material with different wettability on the filtration performance of oil-solid mixed particles has not been fully reported. The objective of this study was to prepare filter materials with varying wettability properties and investigate their filtration performance for oil-solid mixed particles with diverse oil contents. In this study, four filter materials were prepared using the impregnation method, exhibiting 0° (superoleophilic), 46° (oleophilic), 90° and 122° (oleophobic) oil contact angles. The oil-solid mixed particles with varying oil contents were loaded on the four different filter materials. The loading behavior of the filter materials was characterized from two aspects: macroscopic loading behavior (changes in pressure drop and DHC) and microscopic particle deposition behavior. The results demonstrated that, under the conditions of 25% and 50% oil content, the enhanced liquid bridge force between the oil-solid mixed particles on the oleophobic filter material facilitated the formation of a loose and porous cake layer structure compared with other filter materials, resulting in a lower growth rate of pressure drop and a higher dust holding capacity (DHC). However, in 75% and 100% oil content environments, the superoleophilic filter material owned a remarkably high affinity for oil particles compared with other filter materials, leading to the gradual formation of an oil film structure on the filter material, yielding lower the growth rate of pressure drop and higher DHC. These findings shed light on the mechanism of particle deposition under diverse filtration conditions and are applicable to the filtration of various oil-solid mixed particles over a wide range of oil contents.