Key Targets for Improving Algal Biofuel Production
A number of technological challenges need to be overcome if algae are to be utilized for commercial fuel production. Current economic assessment is largely based on laboratory scale up or commercial systems geared to the production of high value products, since no industrial scale plant exits that a...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-10-01
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| Series: | Clean Technologies |
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| Online Access: | https://www.mdpi.com/2571-8797/3/4/43 |
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| author | Gareth Griffiths Abul Kalam Hossain Vikas Sharma Ganesh Duraisamy |
| author_facet | Gareth Griffiths Abul Kalam Hossain Vikas Sharma Ganesh Duraisamy |
| author_sort | Gareth Griffiths |
| collection | DOAJ |
| description | A number of technological challenges need to be overcome if algae are to be utilized for commercial fuel production. Current economic assessment is largely based on laboratory scale up or commercial systems geared to the production of high value products, since no industrial scale plant exits that are dedicated to algal biofuel. For macroalgae (‘seaweeds’), the most promising processes are anaerobic digestion for biomethane production and fermentation for bioethanol, the latter with levels exceeding those from sugar cane. Currently, both processes could be enhanced by increasing the rate of degradation of the complex polysaccharide cell walls to generate fermentable sugars using specifically tailored hydrolytic enzymes. For microalgal biofuel production, open raceway ponds are more cost-effective than photobioreactors, with CO<sub>2</sub> and harvesting/dewatering costs estimated to be ~50% and up to 15% of total costs, respectively. These costs need to be reduced by an order of magnitude if algal biodiesel is to compete with petroleum. Improved economics could be achieved by using a low-cost water supply supplemented with high glucose and nutrients from food grade industrial wastewater and using more efficient flocculation methods and CO<sub>2</sub> from power plants. Solar radiation of not <3000 h·yr<sup>−1</sup> favours production sites 30° north or south of the equator and should use marginal land with flat topography near oceans. Possible geographical sites are discussed. In terms of biomass conversion, advances in wet technologies such as hydrothermal liquefaction, anaerobic digestion, and transesterification for algal biodiesel are presented and how these can be integrated into a biorefinery are discussed. |
| first_indexed | 2024-03-10T04:23:20Z |
| format | Article |
| id | doaj.art-e5f9a26a6bab4e4084da05551135d593 |
| institution | Directory Open Access Journal |
| issn | 2571-8797 |
| language | English |
| last_indexed | 2024-03-10T04:23:20Z |
| publishDate | 2021-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Clean Technologies |
| spelling | doaj.art-e5f9a26a6bab4e4084da05551135d5932023-11-23T07:44:49ZengMDPI AGClean Technologies2571-87972021-10-013471174210.3390/cleantechnol3040043Key Targets for Improving Algal Biofuel ProductionGareth Griffiths0Abul Kalam Hossain1Vikas Sharma2Ganesh Duraisamy3Energy and Bioproducts Research Institute (EBRI), College of Engineering and Physical Sciences, Aston University, Birmingham B4-7ET, UKEnergy and Bioproducts Research Institute (EBRI), College of Engineering and Physical Sciences, Aston University, Birmingham B4-7ET, UKEnergy and Bioproducts Research Institute (EBRI), College of Engineering and Physical Sciences, Aston University, Birmingham B4-7ET, UKInternal Combustion Engineering Division, Department of Mechanical Engineering, Anna University, Chennai 600-025, IndiaA number of technological challenges need to be overcome if algae are to be utilized for commercial fuel production. Current economic assessment is largely based on laboratory scale up or commercial systems geared to the production of high value products, since no industrial scale plant exits that are dedicated to algal biofuel. For macroalgae (‘seaweeds’), the most promising processes are anaerobic digestion for biomethane production and fermentation for bioethanol, the latter with levels exceeding those from sugar cane. Currently, both processes could be enhanced by increasing the rate of degradation of the complex polysaccharide cell walls to generate fermentable sugars using specifically tailored hydrolytic enzymes. For microalgal biofuel production, open raceway ponds are more cost-effective than photobioreactors, with CO<sub>2</sub> and harvesting/dewatering costs estimated to be ~50% and up to 15% of total costs, respectively. These costs need to be reduced by an order of magnitude if algal biodiesel is to compete with petroleum. Improved economics could be achieved by using a low-cost water supply supplemented with high glucose and nutrients from food grade industrial wastewater and using more efficient flocculation methods and CO<sub>2</sub> from power plants. Solar radiation of not <3000 h·yr<sup>−1</sup> favours production sites 30° north or south of the equator and should use marginal land with flat topography near oceans. Possible geographical sites are discussed. In terms of biomass conversion, advances in wet technologies such as hydrothermal liquefaction, anaerobic digestion, and transesterification for algal biodiesel are presented and how these can be integrated into a biorefinery are discussed.https://www.mdpi.com/2571-8797/3/4/43biofuelsmicroalgaemacroalgaebiomethanebioethanolbiohydrogen |
| spellingShingle | Gareth Griffiths Abul Kalam Hossain Vikas Sharma Ganesh Duraisamy Key Targets for Improving Algal Biofuel Production Clean Technologies biofuels microalgae macroalgae biomethane bioethanol biohydrogen |
| title | Key Targets for Improving Algal Biofuel Production |
| title_full | Key Targets for Improving Algal Biofuel Production |
| title_fullStr | Key Targets for Improving Algal Biofuel Production |
| title_full_unstemmed | Key Targets for Improving Algal Biofuel Production |
| title_short | Key Targets for Improving Algal Biofuel Production |
| title_sort | key targets for improving algal biofuel production |
| topic | biofuels microalgae macroalgae biomethane bioethanol biohydrogen |
| url | https://www.mdpi.com/2571-8797/3/4/43 |
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