Biogranulation process facilitates cost-efficient resources recovery from microalgae-based wastewater treatment systems and the creation of a circular bioeconomy

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Author(s)

  • Qian Wang
  • Hui Li
  • Qingyue Shen
  • Jixiang Wang
  • Xingyu Chen
  • Zhenya Zhang
  • Zhongfang Lei
  • Tian Yuan
  • Kazuya Shimizu
  • Yu Liu

Related Research Unit(s)

Detail(s)

Original languageEnglish
Article number154471
Journal / PublicationScience of the Total Environment
Volume828
Online published12 Mar 2022
Publication statusPublished - 1 Jul 2022

Abstract

Energy self-sufficient wastewater treatment designs can reduce net energy consumption and achieve resources recovery. Microalgae are regarded as a promising candidate for developing a circular bioeconomy in wastewater treatment plants (WWTPs) due to its potential for simultaneous wastewater remediation and high value-added materials production. Much effort has been made to overcome the high production costs for microalgae; however, biomass harvesting still remains as the bottleneck for its large-scale application. In this study, the novel biogranulation system facilitating easier and faster microalgae harvesting was firstly compared with the conventional suspended culture for energy-efficiency and sustainability assessment on microalgae (Ankistrodesmus falcatus var. acicularis) cultivation using the synthetic anaerobic digestion liquor. Results demonstrated that the biogranulation system enhanced volumetric biomass productivity (223.17 ± 11.82 g/m3/day) by about 4.4 times compared to that from the suspended system (41.57 ± 2.08 g/m3/day) under the same environmental conditions. It was noticed that lipids, carbohydrates and proteins were accumulated in microalgae cells along with nutrients remediation, and the microalgae granules with much higher proteins content (313.28 ± 26.67 mg/g-VSS) could be easily harvested through 2 min gravity sedimentation with little impact on the contents of carbohydrates and lipids. In the whole cultivation and harvesting process, the biomass mass-based electricity consumption and footprint demand by the biogranulation system were reduced by 58% and 76%, respectively. Results from this study provide a cost-effective and sustainable approach for microalgae in the treatment of nutrients rich digestion liquor with simultaneous production of valuable biomaterials.

Research Area(s)

  • Biogranulation, Circular bioeconomy, Energy efficiency, Microalgae granule, Microalgae harvesting, Resource recovery

Citation Format(s)

Biogranulation process facilitates cost-efficient resources recovery from microalgae-based wastewater treatment systems and the creation of a circular bioeconomy. / Wang, Qian; Li, Hui; Shen, Qingyue; Wang, Jixiang; Chen, Xingyu; Zhang, Zhenya; Lei, Zhongfang; Yuan, Tian; Shimizu, Kazuya; Liu, Yu; Lee, Duu-Jong.

In: Science of the Total Environment, Vol. 828, 154471, 01.07.2022.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review