Pre-coagulation of surface water for mitigating membrane fouling during submerged nanofiltration

IF 8.3 1区工程技术 Q1 ENGINEERING, CHEMICAL

Desalination Pub Date : 2025-04-28 DOI:10.1016/j.desal.2025.118959

Sandrine Boivin , Hideaki Sano , Osamu Nakagoe , Tetsuji Okuda , Takahiro Fujioka

{"title":"Pre-coagulation of surface water for mitigating membrane fouling during submerged nanofiltration","authors":"Sandrine Boivin , Hideaki Sano , Osamu Nakagoe , Tetsuji Okuda , Takahiro Fujioka","doi":"10.1016/j.desal.2025.118959","DOIUrl":null,"url":null,"abstract":"<div><div>Membrane fouling becomes a challenge in nanofiltration (NF) when pre-filtration, such as microfiltration or ultrafiltration, is not performed. This study aimed to identify the potential of pre-coagulation for minimizing membrane fouling during submerged NF membrane treatment. Pre-coagulation (i.e., rapid and slow mixing) before submerged NF treatment was performed by adding optimized doses of ferric chloride (FeCl<sub>3</sub>) or polysilicate iron (PSI). The FeCl<sub>3</sub>-based pre-coagulation only slightly reduced membrane fouling compared to that without pre-coagulation, with a transmembrane pressure (TMP) increase of 9 kPa compared to 18 kPa over 12 days. In contrast, PSI-based pre-coagulation achieved a smaller TMP increase (7 kPa) compared to filtration without pre-coagulation (26 kPa) over 15 days. Interestingly, considerable deposition of foulants was observed on the surface of both NF membranes. Regardless of pre-coagulation, foulants on the membrane surface were removed using one-wipe sponge cleaning, fully restoring membrane permeance. Membrane characterization indicated that FeCl<sub>3</sub> or PSI pre-coagulation resulted in a fouling layer comprising iron, which had low hydraulic resistance. This study identified the potential of PSI-based pre-coagulation for considerably mitigating NF membrane fouling, which reduce the frequency of physical cleaning.</div></div>","PeriodicalId":299,"journal":{"name":"Desalination","volume":"612 ","pages":"Article 118959"},"PeriodicalIF":8.3000,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Desalination","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0011916425004345","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}

引用次数: 0

Abstract

Membrane fouling becomes a challenge in nanofiltration (NF) when pre-filtration, such as microfiltration or ultrafiltration, is not performed. This study aimed to identify the potential of pre-coagulation for minimizing membrane fouling during submerged NF membrane treatment. Pre-coagulation (i.e., rapid and slow mixing) before submerged NF treatment was performed by adding optimized doses of ferric chloride (FeCl₃) or polysilicate iron (PSI). The FeCl₃-based pre-coagulation only slightly reduced membrane fouling compared to that without pre-coagulation, with a transmembrane pressure (TMP) increase of 9 kPa compared to 18 kPa over 12 days. In contrast, PSI-based pre-coagulation achieved a smaller TMP increase (7 kPa) compared to filtration without pre-coagulation (26 kPa) over 15 days. Interestingly, considerable deposition of foulants was observed on the surface of both NF membranes. Regardless of pre-coagulation, foulants on the membrane surface were removed using one-wipe sponge cleaning, fully restoring membrane permeance. Membrane characterization indicated that FeCl₃ or PSI pre-coagulation resulted in a fouling layer comprising iron, which had low hydraulic resistance. This study identified the potential of PSI-based pre-coagulation for considerably mitigating NF membrane fouling, which reduce the frequency of physical cleaning.

Abstract Image

查看原文本刊更多论文

在浸没纳滤过程中对表面水进行预混凝以减轻膜污染

当不进行预过滤（如微滤或超滤）时，膜污染成为纳滤（NF）中的一个挑战。本研究旨在确定在浸没式纳滤膜处理过程中，预混凝对减少膜污染的潜力。通过添加最佳剂量的氯化铁（FeCl3）或聚硅铁（PSI），在浸没式NF处理前进行预混凝（即快速和慢速混合）。与不进行预混凝相比，基于fecl3的预混凝仅略微减少了膜污染，跨膜压力（TMP）在12天内增加了9 kPa，而非18 kPa。相比之下，在15天内，基于psi的预凝比没有预凝的过滤（26 kPa）获得了较小的TMP增加（7 kPa）。有趣的是，在两种纳滤膜表面都观察到大量的污染物沉积。无论是否进行预混凝，使用海绵一次性清洗去除膜表面的污垢，充分恢复膜的通透性。膜表征表明，FeCl3或PSI预混凝形成含铁的污染层，具有较低的水力阻力。本研究确定了基于psi的预混凝的潜力，可以显著减轻纳滤膜污染，减少物理清洗的频率。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Desalination 工程技术-工程：化工

CiteScore

14.60

自引率

20.20%

发文量

619

审稿时长

41 days

期刊介绍： Desalination is a scholarly journal that focuses on the field of desalination materials, processes, and associated technologies. It encompasses a wide range of disciplines and aims to publish exceptional papers in this area. The journal invites submissions that explicitly revolve around water desalting and its applications to various sources such as seawater, groundwater, and wastewater. It particularly encourages research on diverse desalination methods including thermal, membrane, sorption, and hybrid processes. By providing a platform for innovative studies, Desalination aims to advance the understanding and development of desalination technologies, promoting sustainable solutions for water scarcity challenges.