Filter Media-Packed Bed Reactor Fortification with Biochar to Enhance Wastewater Quality
Contamination of water sources by inappropriately disposed poorly treated wastewater from countryside establishments is a worldwide challenge. This study tested the effectiveness of retrofitting sand (Sa)- and gas−concrete (GC)-packed reactors with biochar (C) in removing turbidity, dissol...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-01-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/10/3/790 |
| _version_ | 1818040478812078080 |
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| author | Ezekiel Kholoma Agnieszka Renman Gunno Renman |
| author_facet | Ezekiel Kholoma Agnieszka Renman Gunno Renman |
| author_sort | Ezekiel Kholoma |
| collection | DOAJ |
| description | Contamination of water sources by inappropriately disposed poorly treated wastewater from countryside establishments is a worldwide challenge. This study tested the effectiveness of retrofitting sand (Sa)- and gas−concrete (GC)-packed reactors with biochar (C) in removing turbidity, dissolved organic carbon (DOC), phosphate (PO<sub>4</sub><sup>3−</sup>), and total phosphorus (P<sub>tot</sub>) from wastewater. The down-flow reactors were each intermittently loaded with 0.063 L/d for 399 days. In general, all reactors achieved <3 NTU (Nephelometric Turbidity Units) effluent turbidity (99% efficiency). GC reactors dominated in inlet PO<sub>4</sub><sup>3−</sup> (6.1 mg/L) and DOC (25.3 mg/L) reduction, trapping >95% and >60%, respectively. Compared to Sa (PO<sub>4</sub><sup>3−</sup>: 35%, DOC: 52%), the fortified sand (SaC) filter attenuated more PO<sub>4</sub><sup>3−</sup> (>42%) and DOC (>58%). Student t-tests revealed that C significantly improved the Sa PO<sub>4</sub><sup>3−</sup> (<i>p</i> = 0.022) and DOC (<i>p</i> = 0.034) removal efficacy. From regression analysis, 53%, 81%, and 85% PO<sub>4</sub><sup>3−</sup> sorption variation in Sa, C, and SaC, respectively, were explained by variation in their effluent pH measures. Similarly, a strong linear correlation occurred between PO<sub>4</sub><sup>3−</sup> sorption efficiency and pH of fortified (r > 0.7) and reference (r = 0.6) GC filters thus suggesting chemisorption mechanisms. Therefore, whereby only sand may be available for treating septic tank effluents, fortifying it with biochar may be a possible measure to improve its efficacy. |
| first_indexed | 2024-12-10T08:15:10Z |
| format | Article |
| id | doaj.art-b99dfd38ebbf4e4b89dd3b86b2880375 |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-12-10T08:15:10Z |
| publishDate | 2020-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-b99dfd38ebbf4e4b89dd3b86b28803752022-12-22T01:56:29ZengMDPI AGApplied Sciences2076-34172020-01-0110379010.3390/app10030790app10030790Filter Media-Packed Bed Reactor Fortification with Biochar to Enhance Wastewater QualityEzekiel Kholoma0Agnieszka Renman1Gunno Renman2Department of Civil & Environmental Engineering, Botswana International University of Science & Technology, Private Bag 16, Palapye, BotswanaDivision of Water and Environmental Engineering, KTH Royal Institute of Technology, 100 44 Stockholm, SwedenDivision of Water and Environmental Engineering, KTH Royal Institute of Technology, 100 44 Stockholm, SwedenContamination of water sources by inappropriately disposed poorly treated wastewater from countryside establishments is a worldwide challenge. This study tested the effectiveness of retrofitting sand (Sa)- and gas−concrete (GC)-packed reactors with biochar (C) in removing turbidity, dissolved organic carbon (DOC), phosphate (PO<sub>4</sub><sup>3−</sup>), and total phosphorus (P<sub>tot</sub>) from wastewater. The down-flow reactors were each intermittently loaded with 0.063 L/d for 399 days. In general, all reactors achieved <3 NTU (Nephelometric Turbidity Units) effluent turbidity (99% efficiency). GC reactors dominated in inlet PO<sub>4</sub><sup>3−</sup> (6.1 mg/L) and DOC (25.3 mg/L) reduction, trapping >95% and >60%, respectively. Compared to Sa (PO<sub>4</sub><sup>3−</sup>: 35%, DOC: 52%), the fortified sand (SaC) filter attenuated more PO<sub>4</sub><sup>3−</sup> (>42%) and DOC (>58%). Student t-tests revealed that C significantly improved the Sa PO<sub>4</sub><sup>3−</sup> (<i>p</i> = 0.022) and DOC (<i>p</i> = 0.034) removal efficacy. From regression analysis, 53%, 81%, and 85% PO<sub>4</sub><sup>3−</sup> sorption variation in Sa, C, and SaC, respectively, were explained by variation in their effluent pH measures. Similarly, a strong linear correlation occurred between PO<sub>4</sub><sup>3−</sup> sorption efficiency and pH of fortified (r > 0.7) and reference (r = 0.6) GC filters thus suggesting chemisorption mechanisms. Therefore, whereby only sand may be available for treating septic tank effluents, fortifying it with biochar may be a possible measure to improve its efficacy.https://www.mdpi.com/2076-3417/10/3/790wastewater treatmentbiocharpacked bed reactorfortificationphosphorusdissolved organic carbon |
| spellingShingle | Ezekiel Kholoma Agnieszka Renman Gunno Renman Filter Media-Packed Bed Reactor Fortification with Biochar to Enhance Wastewater Quality Applied Sciences wastewater treatment biochar packed bed reactor fortification phosphorus dissolved organic carbon |
| title | Filter Media-Packed Bed Reactor Fortification with Biochar to Enhance Wastewater Quality |
| title_full | Filter Media-Packed Bed Reactor Fortification with Biochar to Enhance Wastewater Quality |
| title_fullStr | Filter Media-Packed Bed Reactor Fortification with Biochar to Enhance Wastewater Quality |
| title_full_unstemmed | Filter Media-Packed Bed Reactor Fortification with Biochar to Enhance Wastewater Quality |
| title_short | Filter Media-Packed Bed Reactor Fortification with Biochar to Enhance Wastewater Quality |
| title_sort | filter media packed bed reactor fortification with biochar to enhance wastewater quality |
| topic | wastewater treatment biochar packed bed reactor fortification phosphorus dissolved organic carbon |
| url | https://www.mdpi.com/2076-3417/10/3/790 |
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