Comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite, hydrogen peroxide, acid and alkaline : implications for on-line chemical cleaning of MBR
Although on-line chemical cleaning has been extensively employed for maintaining the MBR permeability, little attention has been given to the negative impacts of such prevalent membrane cleaning practice. This study thus comparatively investigated the potential release of dissolved organic matter (D...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2020
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| Online Access: | https://hdl.handle.net/10356/139904 |
| _version_ | 1826126937554157568 |
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| author | Cai, Weiwei Liu, Yu |
| author2 | School of Civil and Environmental Engineering |
| author_facet | School of Civil and Environmental Engineering Cai, Weiwei Liu, Yu |
| author_sort | Cai, Weiwei |
| collection | NTU |
| description | Although on-line chemical cleaning has been extensively employed for maintaining the MBR permeability, little attention has been given to the negative impacts of such prevalent membrane cleaning practice. This study thus comparatively investigated the potential release of dissolved organic matter (DOM) from activated sludge upon the exposure to different kinds of frequently-used cleaning reagents, i.e. NaClO, H2O2, HCl and NaOH. It was found that NaClO at 50 and 80 mg L-1 triggered significant release of DOM, while NaOH strongly promoted soluble nitrogen release. However, the DOM generation induced by H2O2 in the range of 0-80 mg L-1 was nearly negligible. The combined analysis by EEM-PARAFAC and LC-OCD-OND further revealed that NaClO-triggered DOM mainly originated from the breakdown of humic substances and other small humics with molecular weight (MW) less than 500 Da. In contrast, proteins and other biopolymers with higher MW highly contributed to DOM induced by NaOH. Most of DOM detected in this study belonged to low molecular weight (LMW) substances, which were not considered readily biodegradable or physically retainable by microfiltration membrane. It appears from this study that DOM generated from suspended activated sludge during membrane cleaning with different chemicals should be taken into serious consideration when water recycle and reuse are concerned. |
| first_indexed | 2024-10-01T07:00:36Z |
| format | Journal Article |
| id | ntu-10356/139904 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T07:00:36Z |
| publishDate | 2020 |
| record_format | dspace |
| spelling | ntu-10356/1399042020-05-22T07:52:26Z Comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite, hydrogen peroxide, acid and alkaline : implications for on-line chemical cleaning of MBR Cai, Weiwei Liu, Yu School of Civil and Environmental Engineering Advanced Environmental Biotechnology Centre Nanyang Environment and Water Research Institute Engineering::Civil engineering On-line Chemical Cleaning Cleaning Reagent Although on-line chemical cleaning has been extensively employed for maintaining the MBR permeability, little attention has been given to the negative impacts of such prevalent membrane cleaning practice. This study thus comparatively investigated the potential release of dissolved organic matter (DOM) from activated sludge upon the exposure to different kinds of frequently-used cleaning reagents, i.e. NaClO, H2O2, HCl and NaOH. It was found that NaClO at 50 and 80 mg L-1 triggered significant release of DOM, while NaOH strongly promoted soluble nitrogen release. However, the DOM generation induced by H2O2 in the range of 0-80 mg L-1 was nearly negligible. The combined analysis by EEM-PARAFAC and LC-OCD-OND further revealed that NaClO-triggered DOM mainly originated from the breakdown of humic substances and other small humics with molecular weight (MW) less than 500 Da. In contrast, proteins and other biopolymers with higher MW highly contributed to DOM induced by NaOH. Most of DOM detected in this study belonged to low molecular weight (LMW) substances, which were not considered readily biodegradable or physically retainable by microfiltration membrane. It appears from this study that DOM generated from suspended activated sludge during membrane cleaning with different chemicals should be taken into serious consideration when water recycle and reuse are concerned. 2020-05-22T07:52:26Z 2020-05-22T07:52:26Z 2018 Journal Article Cai, W., & Liu, Y. (2018). Comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite, hydrogen peroxide, acid and alkaline : implications for on-line chemical cleaning of MBR. Chemosphere, 193, 295-303. doi:10.1016/j.chemosphere.2017.11.032 0045-6535 https://hdl.handle.net/10356/139904 10.1016/j.chemosphere.2017.11.032 29145090 2-s2.0-85034107179 193 295 303 en Chemosphere © 2017 Elsevier Ltd. All rights reserved. |
| spellingShingle | Engineering::Civil engineering On-line Chemical Cleaning Cleaning Reagent Cai, Weiwei Liu, Yu Comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite, hydrogen peroxide, acid and alkaline : implications for on-line chemical cleaning of MBR |
| title | Comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite, hydrogen peroxide, acid and alkaline : implications for on-line chemical cleaning of MBR |
| title_full | Comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite, hydrogen peroxide, acid and alkaline : implications for on-line chemical cleaning of MBR |
| title_fullStr | Comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite, hydrogen peroxide, acid and alkaline : implications for on-line chemical cleaning of MBR |
| title_full_unstemmed | Comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite, hydrogen peroxide, acid and alkaline : implications for on-line chemical cleaning of MBR |
| title_short | Comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite, hydrogen peroxide, acid and alkaline : implications for on-line chemical cleaning of MBR |
| title_sort | comparative study of dissolved organic matter generated from activated sludge during exposure to hypochlorite hydrogen peroxide acid and alkaline implications for on line chemical cleaning of mbr |
| topic | Engineering::Civil engineering On-line Chemical Cleaning Cleaning Reagent |
| url | https://hdl.handle.net/10356/139904 |
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