Continuation of a cleaning process: Application of MNBs-coagulation process to mitigate ultrafiltration membrane fouling

Xiaojiang Huang; Kunyu Chen; Zhiqiang Zhang; Heliang Pang; Xingxing Huang; Jing Yang; Xuan Wang; Jinsuo Lu

doi:10.1016/j.watres.2023.121032

Continuation of a cleaning process: Application of MNBs-coagulation process to mitigate ultrafiltration membrane fouling

Water Res. 2024 Feb 15:250:121032. doi: 10.1016/j.watres.2023.121032. Epub 2023 Dec 18.

Authors

Xiaojiang Huang¹, Kunyu Chen¹, Zhiqiang Zhang², Heliang Pang², Xingxing Huang¹, Jing Yang², Xuan Wang², Jinsuo Lu³

Affiliations

¹ School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
² School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; State Key Laboratory of Green Building in West China, Xi'an University of Architecture and Technology, Xi'an 710055, China.
³ School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; State Key Laboratory of Green Building in West China, Xi'an University of Architecture and Technology, Xi'an 710055, China. Electronic address: lujinsuo@xauat.edu.cn.

PMID: 38157598
DOI: 10.1016/j.watres.2023.121032

Abstract

The MNBs-coagulation process as a novel and cleaning enhanced coagulation process has been demonstrated to enhance the removal efficiency of hydrophilic organics. In this study, while continuing the concept of cleaning production, the MNBs-coagulation process was first applied to the ultrafiltration process and was expected to alleviate the ultrafiltration membrane fouling. This study investigated the effect of the involvement of MNBs in coagulation-ultrafiltration process (the MC-UF process) on the fouling behaviour of ultrafiltration membrane based on the calculation of membrane resistance distribution and the fitting of membrane fouling model. In addition, the NOM removal efficiency, floc characteristics analysis and membrane hydrophilicity analysis were used to illustrate the mechanism of mitigating ultrafiltration mebrane fouling by the MC-UF process. The experimental results showed that the involvement of MNBs in the coagulation-ultrafiltration process was able to reduce the irreversible fouling and TMP by 43.1 % and 41.6 % respectively. This phenomenon could be attributed to the involvement of MNBs in the coagulation process to improve the removal efficiency of hydrophilic organics and to enhance the characteristics of flocs, thus reducing the possibility of hydrophilic organics and broken flocs entering and blocking the membrane pores. In addition, the FT-IR spectral changes before and after the floc breakage were analyzed by 2D-COS technique in this study, and it was found for the first time that the participation of MNBs in the coagulation process could change the sequence of functional group transformation within the floc, and promote the generation of hydrogen bonds between flocs by hindering the generation of hydroxyl groups (-OH), and improve the shear resistance and regrowth capacity of flocs while reducing the possibility of broken flocs entering and blocking membrane pores. In summary, the MC-UF process proposed in this study can significantly mitigate ultrafiltration membrane fouling while meeting cleaning production, providing theoretical support for the application of the process to practical engineering.

Keywords: Cleaning production; Enhanced coagulation; Flocs morphology; Micro-nano bubbles.

MeSH terms

Flocculation
Humic Substances / analysis
Membranes, Artificial
Spectroscopy, Fourier Transform Infrared
Ultrafiltration* / methods
Water Purification* / methods

Substances

Membranes, Artificial
Humic Substances