Use of rotating membranes for air-to-liquid mass transfer of carbon dioxide to enhance algal growth
A novel air-to-liquid mass transfer system using wetted rotating membranes was designed to enhance air-to-liquid carbon dioxide (CO2) mass transfer efficiency. Traditional methods, such as sparging, are energy-intensive, but the rotating membrane reduces energy demands by optimising membrane wetting...
| Veröffentlicht in: | Environmental technology. - 1993. - (2024) vom: 31. Dez., Seite 1-19 |
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| Weitere Verfasser: | , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2024
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| Zugriff auf das übergeordnete Werk: | Environmental technology |
| Schlagworte: | Journal Article Algal growth carbon dioxide capture mass transfer techno-economic analysis wetted rotating membranes |
| Zusammenfassung: | A novel air-to-liquid mass transfer system using wetted rotating membranes was designed to enhance air-to-liquid carbon dioxide (CO2) mass transfer efficiency. Traditional methods, such as sparging, are energy-intensive, but the rotating membrane reduces energy demands by optimising membrane wetting via rotational motion. Experimental tests were conducted using a small-scale system with a membrane width of 0.64 m and loop size of 2 to 5 m, with rotational speeds between 0.0 and 0.78 m/s. CO2 flux increased by up to 45%, achieving maximum uptake rate of 9.14 mg CO2/min/m2 at 100% speed. An empirical model was developed to predict mass transfer rates under varying operational conditions, and model validation showed a strong correlation with experimental data (R2 = 0.9668). Preliminary techno-economic analysis estimated that scaling the system to meet the CO2 demands of a hypothetical 500,000 L raceway, 915 membranes would be required, utilising ∼223 m2 (13.4%) of 1667 m2 surface area, assuming a 0.3 m depth, 12 g/m2/day growth rate, and algae with 50% carbon by weight. The system's energy consumption was measured at 17.1 J/g CO2 captured, representing a 90% reduction in power usage compared to conventional sparging systems, which typically require ∼627 W per 8.3 m2 of membrane surface area. Based solely on electricity costs of $0.10/kW-hr, the cost of capturing atmospheric CO2 was estimated at $1550 per ton. This marks a significant improvement over existing technologies, enhancing commercial viability. Future work will validate the system with Chlorella vulgaris and scale to optimise CO2 capture and reduce costs |
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| Beschreibung: | Date Revised 31.12.2024 published: Print-Electronic Citation Status Publisher |
| ISSN: | 1479-487X |
| DOI: | 10.1080/09593330.2024.2445328 |