Roles of Sulfites in Reverse Osmosis (RO) Plants and Adverse Effects in RO Operation
More than 60 years have passed since UCLA first announced the development of an innovative asymmetric cellulose acetate reverse osmosis (RO) membrane in 1960. This innovation opened a gate to use RO for commercial use. RO is now ubiquitous in water treatment and has been used for various application...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-01-01
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| Series: | Membranes |
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| Online Access: | https://www.mdpi.com/2077-0375/12/2/170 |
| _version_ | 1797478173649141760 |
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| author | Yasushi Maeda |
| author_facet | Yasushi Maeda |
| author_sort | Yasushi Maeda |
| collection | DOAJ |
| description | More than 60 years have passed since UCLA first announced the development of an innovative asymmetric cellulose acetate reverse osmosis (RO) membrane in 1960. This innovation opened a gate to use RO for commercial use. RO is now ubiquitous in water treatment and has been used for various applications, including seawater desalination, municipal water treatment, wastewater reuse, ultra-pure water (UPW) production, and industrial process waters, etc. RO is a highly integrated system consisting of a series of unit processes: (1) intake system, (2) pretreatment, (3) RO system, (4) post-treatment, and (5) effluent treatment and discharge system. In each step, a variety of chemicals are used. Among those, sulfites (sodium bisulfite and sodium metabisulfite) have played significant roles in RO, such as dechlorination, preservatives, shock treatment, and sanitization, etc. Sulfites especially became necessary as dechlorinating agents because polyamide hollow-fiber and aromatic thin-film composite RO membranes developed in the late 1960s and 1970s were less tolerable with residual chlorine. In this review, key applications of sulfites are explained in detail. Furthermore, as it is reported that sulfites have some adverse effects on RO membranes and processes, such phenomena will be clarified. In particular, the following two are significant concerns using sulfites: RO membrane oxidation catalyzed by heavy metals and a trigger of biofouling. This review sheds light on the mechanism of membrane oxidation and triggering biofouling by sulfites. Some countermeasures are also introduced to alleviate such problems. |
| first_indexed | 2024-03-09T21:28:14Z |
| format | Article |
| id | doaj.art-1edd9d02f7cf496d92a27409666edf01 |
| institution | Directory Open Access Journal |
| issn | 2077-0375 |
| language | English |
| last_indexed | 2024-03-09T21:28:14Z |
| publishDate | 2022-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Membranes |
| spelling | doaj.art-1edd9d02f7cf496d92a27409666edf012023-11-23T21:02:56ZengMDPI AGMembranes2077-03752022-01-0112217010.3390/membranes12020170Roles of Sulfites in Reverse Osmosis (RO) Plants and Adverse Effects in RO OperationYasushi Maeda0LG Chem Japan Co., Ltd., Kyobashi Trust Tower 12F, 2-1-3 Kyobashi Chuo-ku, Tokyo 104-0031, JapanMore than 60 years have passed since UCLA first announced the development of an innovative asymmetric cellulose acetate reverse osmosis (RO) membrane in 1960. This innovation opened a gate to use RO for commercial use. RO is now ubiquitous in water treatment and has been used for various applications, including seawater desalination, municipal water treatment, wastewater reuse, ultra-pure water (UPW) production, and industrial process waters, etc. RO is a highly integrated system consisting of a series of unit processes: (1) intake system, (2) pretreatment, (3) RO system, (4) post-treatment, and (5) effluent treatment and discharge system. In each step, a variety of chemicals are used. Among those, sulfites (sodium bisulfite and sodium metabisulfite) have played significant roles in RO, such as dechlorination, preservatives, shock treatment, and sanitization, etc. Sulfites especially became necessary as dechlorinating agents because polyamide hollow-fiber and aromatic thin-film composite RO membranes developed in the late 1960s and 1970s were less tolerable with residual chlorine. In this review, key applications of sulfites are explained in detail. Furthermore, as it is reported that sulfites have some adverse effects on RO membranes and processes, such phenomena will be clarified. In particular, the following two are significant concerns using sulfites: RO membrane oxidation catalyzed by heavy metals and a trigger of biofouling. This review sheds light on the mechanism of membrane oxidation and triggering biofouling by sulfites. Some countermeasures are also introduced to alleviate such problems.https://www.mdpi.com/2077-0375/12/2/170bisulfitemetabisulfitereverse osmosisdechlorinationORPchloramine |
| spellingShingle | Yasushi Maeda Roles of Sulfites in Reverse Osmosis (RO) Plants and Adverse Effects in RO Operation Membranes bisulfite metabisulfite reverse osmosis dechlorination ORP chloramine |
| title | Roles of Sulfites in Reverse Osmosis (RO) Plants and Adverse Effects in RO Operation |
| title_full | Roles of Sulfites in Reverse Osmosis (RO) Plants and Adverse Effects in RO Operation |
| title_fullStr | Roles of Sulfites in Reverse Osmosis (RO) Plants and Adverse Effects in RO Operation |
| title_full_unstemmed | Roles of Sulfites in Reverse Osmosis (RO) Plants and Adverse Effects in RO Operation |
| title_short | Roles of Sulfites in Reverse Osmosis (RO) Plants and Adverse Effects in RO Operation |
| title_sort | roles of sulfites in reverse osmosis ro plants and adverse effects in ro operation |
| topic | bisulfite metabisulfite reverse osmosis dechlorination ORP chloramine |
| url | https://www.mdpi.com/2077-0375/12/2/170 |
| work_keys_str_mv | AT yasushimaeda rolesofsulfitesinreverseosmosisroplantsandadverseeffectsinrooperation |