4.7 Article

Sodium hypochlorite-assisted osmotic backwashing for mitigating forward osmosis membrane fouling during pre-concentrating wastewater

期刊

出版社

ELSEVIER
DOI: 10.1016/j.eti.2023.103402

关键词

Forward osmosis membrane; Pre-concentration of wastewater; NaClO; Osmotic backwash; Membrane cleaning

向作者/读者索取更多资源

This study assessed the effectiveness of sodium hypochlorite-assisted osmotic backwashing in reducing fouling of FO membrane and found that low concentration NaClO cleaning strategy can achieve higher water flux restoration.
Forward osmosis (FO) membrane has drawn substantial attention to pre-concentrating organic matter in wastewater for biogas production. However, membrane fouling control is an ongoing challenge for the feasibility of the FO system. Although chemical cleaning using a caustic solution (e.g., solution pH = 11) can remove organic foulants on the polyamide-based membranes, it can damage cellulose triacetate (CTA)-based FO membrane due to hydrolysis. This study assessed the efficacy of sodium hypochlorite (NaClO)-assisted osmotic backwashing to mitigate CTA-based FO membrane fouling during pre-concentrating primary wastewater effluent. The cleaning strategy employing a low concentration of NaClO achieved a higher restoration of water flux than conventional hydraulic flushing and sole osmotic backwashing. The water flux after NaClO-assisted osmotic backwashing (NaClO concentrations = 10-80 mg/L) reached 97-102%. Irreversible foulants on the membrane surface were fully removed by NaClO concentration from 20 to 80 mg/ L. During four filtration cycles using a 40 mg-NaClO/L cleaning solution, the reverse salt flux increased from 4.3 to 6.3 g/m2h. This indicates that for a long-term operation, applying lower concentrations of NaClO (e.g., 20 mg/L) may be needed to avoid the changes in reverse salt flux. This study suggests that FO membranes during pre-concentrating primary wastewater effluent can be stably operated with NaClO-assisted osmotic backwashing.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.7
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据