Floating treatment islands in series along a channel: The impact of island spacing on the velocity field and estimated mass removal.
Floating treatment islands (FTIs) consist of emergent vegetation grown on floating structures. The submerged roots beneath the island and the biofilm they support filter nutrients and particulates from water passing through the roots. FTIs are often deployed in series within a channel, but an optimu...
| Main Authors: | , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | English |
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Elsevier BV
2020
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| Online Access: | https://hdl.handle.net/1721.1/126713 |
| _version_ | 1826193710762688512 |
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| author | Liu, Chao Shan, Yuqi Lei, Jiarui Nepf, Heidi |
| author2 | Massachusetts Institute of Technology. Department of Civil and Environmental Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Civil and Environmental Engineering Liu, Chao Shan, Yuqi Lei, Jiarui Nepf, Heidi |
| author_sort | Liu, Chao |
| collection | MIT |
| description | Floating treatment islands (FTIs) consist of emergent vegetation grown on floating structures. The submerged roots beneath the island and the biofilm they support filter nutrients and particulates from water passing through the roots. FTIs are often deployed in series within a channel, but an optimum spacing between FTIs has not yet been determined. The goal of the present study is to identify an optimum spacing for maximum mass removal per channel length. A series of scaled FTI models were deployed in a water channel with the spacing between FTIs ranging from 0.5 to 11 times the length of an individual root zone. A Nortek Vectrino was used to measure the velocity field to determine the flow rate into and residence time within each root zone. The measured flow distribution was used within a control volume analysis to estimate the mass removed per channel length, assuming that removal within the root zone followed a first-order reaction. As the spacing between the FTIs decreased, the flow entering each FTI root zone also decreased, which decreased the mass removed by each individual FTI. However, as the spacing between FTIs was decreased, the number of FTIs per channel length increased, which tended to increase the mass removal of the system of FTI in series. These competing trends produced a maximum mass removal for FTIs spaced between one and three times the root zone length. The maximum spacing was weakly dependent on the assumed first-order reaction rate. The present study can help designers choose an optimal spacing for FTIs in series to achieve the maximum mass removal per river length. |
| first_indexed | 2024-09-23T09:43:33Z |
| format | Article |
| id | mit-1721.1/126713 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T09:43:33Z |
| publishDate | 2020 |
| publisher | Elsevier BV |
| record_format | dspace |
| spelling | mit-1721.1/1267132024-02-13T21:05:36Z Floating treatment islands in series along a channel: The impact of island spacing on the velocity field and estimated mass removal. Liu, Chao Shan, Yuqi Lei, Jiarui Nepf, Heidi Massachusetts Institute of Technology. Department of Civil and Environmental Engineering Floating treatment islands (FTIs) consist of emergent vegetation grown on floating structures. The submerged roots beneath the island and the biofilm they support filter nutrients and particulates from water passing through the roots. FTIs are often deployed in series within a channel, but an optimum spacing between FTIs has not yet been determined. The goal of the present study is to identify an optimum spacing for maximum mass removal per channel length. A series of scaled FTI models were deployed in a water channel with the spacing between FTIs ranging from 0.5 to 11 times the length of an individual root zone. A Nortek Vectrino was used to measure the velocity field to determine the flow rate into and residence time within each root zone. The measured flow distribution was used within a control volume analysis to estimate the mass removed per channel length, assuming that removal within the root zone followed a first-order reaction. As the spacing between the FTIs decreased, the flow entering each FTI root zone also decreased, which decreased the mass removed by each individual FTI. However, as the spacing between FTIs was decreased, the number of FTIs per channel length increased, which tended to increase the mass removal of the system of FTI in series. These competing trends produced a maximum mass removal for FTIs spaced between one and three times the root zone length. The maximum spacing was weakly dependent on the assumed first-order reaction rate. The present study can help designers choose an optimal spacing for FTIs in series to achieve the maximum mass removal per river length. 2020-08-20T21:39:50Z 2020-08-20T21:39:50Z 2019-07 2019-04 2020-08-19T17:31:07Z Article http://purl.org/eprint/type/JournalArticle 0309-1708 https://hdl.handle.net/1721.1/126713 Liu, Chao et al. "Floating treatment islands in series along a channel: The impact of island spacing on the velocity field and estimated mass removal." Advances in Water Resources 129 (July 2019): 222-231 © 2019 Elsevier Ltd en http://dx.doi.org/10.1016/j.advwatres.2019.05.011 Advances in Water Resources Creative Commons Attribution-NonCommercial-NoDerivs License http://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf Elsevier BV Prof. Nepf via Elizabeth Soergel |
| spellingShingle | Liu, Chao Shan, Yuqi Lei, Jiarui Nepf, Heidi Floating treatment islands in series along a channel: The impact of island spacing on the velocity field and estimated mass removal. |
| title | Floating treatment islands in series along a channel: The impact of island spacing on the velocity field and estimated mass removal. |
| title_full | Floating treatment islands in series along a channel: The impact of island spacing on the velocity field and estimated mass removal. |
| title_fullStr | Floating treatment islands in series along a channel: The impact of island spacing on the velocity field and estimated mass removal. |
| title_full_unstemmed | Floating treatment islands in series along a channel: The impact of island spacing on the velocity field and estimated mass removal. |
| title_short | Floating treatment islands in series along a channel: The impact of island spacing on the velocity field and estimated mass removal. |
| title_sort | floating treatment islands in series along a channel the impact of island spacing on the velocity field and estimated mass removal |
| url | https://hdl.handle.net/1721.1/126713 |
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