The Evaluation of a Novel Denitrifying Woodchip Bioreactor: Fairmont, MN, USA
The risk of nitrate contamination became a reality for Fairmont in Minnesota, when water rich in NO<sub>3</sub>-N exceeded the drinking water standard of 10 mg/L. This was unexpected because this city draws its municipal water from a chain of lakes that are fed primarily by shallow groun...
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-02-01
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| Series: | Nitrogen |
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| Online Access: | https://www.mdpi.com/2504-3129/5/1/10 |
| _version_ | 1827305404964536320 |
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| author | Limeimei Xu Kerry Holmberg Joe Magner |
| author_facet | Limeimei Xu Kerry Holmberg Joe Magner |
| author_sort | Limeimei Xu |
| collection | DOAJ |
| description | The risk of nitrate contamination became a reality for Fairmont in Minnesota, when water rich in NO<sub>3</sub>-N exceeded the drinking water standard of 10 mg/L. This was unexpected because this city draws its municipal water from a chain of lakes that are fed primarily by shallow groundwater under row-crop land use. Spring soil thaw drives cold water into a subsurface pipe where almost no NO<sub>3</sub>-N reduction occurs. This paper focuses on NO<sub>3</sub>-N reduction before the water enters the lakes and no other nitrogen management practices in the watershed. A novel denitrifying bioreactor was constructed behind a sediment forebay, which then flowed into a chamber covered by a greenhouse before entering a woodchip bioreactor. In 2022 and 2023, water depth, dissolved oxygen, and temperature were measured at several locations in the bioreactor, and continuous NO<sub>3</sub>-N was measured at the entry and exit of the bioreactor. The results showed better performance at a low water depth with lower dissolved oxygen and higher water temperature. The greenhouse raised the inlet temperature in 2022 but did not in 2023. The forebay and the greenhouse may have impeded the denitrification process due to the high dissolved oxygen concentrations in the influent and the stratification of dissolved oxygen caused by algae in the bioreactor. |
| first_indexed | 2024-04-24T17:57:38Z |
| format | Article |
| id | doaj.art-d80dae72ebff45fd875d8fd258a3195d |
| institution | Directory Open Access Journal |
| issn | 2504-3129 |
| language | English |
| last_indexed | 2024-04-24T17:57:38Z |
| publishDate | 2024-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Nitrogen |
| spelling | doaj.art-d80dae72ebff45fd875d8fd258a3195d2024-03-27T13:57:47ZengMDPI AGNitrogen2504-31292024-02-015115216210.3390/nitrogen5010010The Evaluation of a Novel Denitrifying Woodchip Bioreactor: Fairmont, MN, USALimeimei Xu0Kerry Holmberg1Joe Magner2Department of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, MN 55108, USADepartment of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, MN 55108, USADepartment of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, MN 55108, USAThe risk of nitrate contamination became a reality for Fairmont in Minnesota, when water rich in NO<sub>3</sub>-N exceeded the drinking water standard of 10 mg/L. This was unexpected because this city draws its municipal water from a chain of lakes that are fed primarily by shallow groundwater under row-crop land use. Spring soil thaw drives cold water into a subsurface pipe where almost no NO<sub>3</sub>-N reduction occurs. This paper focuses on NO<sub>3</sub>-N reduction before the water enters the lakes and no other nitrogen management practices in the watershed. A novel denitrifying bioreactor was constructed behind a sediment forebay, which then flowed into a chamber covered by a greenhouse before entering a woodchip bioreactor. In 2022 and 2023, water depth, dissolved oxygen, and temperature were measured at several locations in the bioreactor, and continuous NO<sub>3</sub>-N was measured at the entry and exit of the bioreactor. The results showed better performance at a low water depth with lower dissolved oxygen and higher water temperature. The greenhouse raised the inlet temperature in 2022 but did not in 2023. The forebay and the greenhouse may have impeded the denitrification process due to the high dissolved oxygen concentrations in the influent and the stratification of dissolved oxygen caused by algae in the bioreactor.https://www.mdpi.com/2504-3129/5/1/10denitrifying woodchip bioreactornitrate removalnovelgreenhouse |
| spellingShingle | Limeimei Xu Kerry Holmberg Joe Magner The Evaluation of a Novel Denitrifying Woodchip Bioreactor: Fairmont, MN, USA Nitrogen denitrifying woodchip bioreactor nitrate removal novel greenhouse |
| title | The Evaluation of a Novel Denitrifying Woodchip Bioreactor: Fairmont, MN, USA |
| title_full | The Evaluation of a Novel Denitrifying Woodchip Bioreactor: Fairmont, MN, USA |
| title_fullStr | The Evaluation of a Novel Denitrifying Woodchip Bioreactor: Fairmont, MN, USA |
| title_full_unstemmed | The Evaluation of a Novel Denitrifying Woodchip Bioreactor: Fairmont, MN, USA |
| title_short | The Evaluation of a Novel Denitrifying Woodchip Bioreactor: Fairmont, MN, USA |
| title_sort | evaluation of a novel denitrifying woodchip bioreactor fairmont mn usa |
| topic | denitrifying woodchip bioreactor nitrate removal novel greenhouse |
| url | https://www.mdpi.com/2504-3129/5/1/10 |
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