Pilot-scale phycoremediation using Muriellopsis sp. for wastewater reclamation in the Atacama Desert: microalgae biomass production and pigment recovery

Abstract

Municipal wastewater phycoremediation represents a promising circular economy-based process for wastewater reclamation used to recover water and produce biomass. This study aimed to evaluate a pilot-scale phycoremediation system, using the most efficient strain of microalgae for wastewater reclamation in the Atacama Desert. Nitrogen and phosphorus removal, as well as biomass growth, were compared in different microalgae treatments, namely Muriellopsis sp., Scenedesmus almeriensis, Chlamydomonas segnis, Chlorella pyrenoidosa and Chlorella vulgaris. The most efficient treatments, Muriellopsis sp. and S. almeriensis, were scaled up to 20-L bubble column reactors to evaluate nutrient removal and biomass biochemical profile for potential biotechnological application. Finally, Muriellopsis sp. was selected for a pilot-scale phycoremediation experiment (800-L raceway), which removed 84% of nitrogen, 93% of phosphorus and other chemical compounds after 4 days of treatment to meet most of the Chilean standards for irrigation water (NCh. 1333. DS. MOP No. 867/78). Faecal coliforms count was reduced by 99.9%. Furthermore, biomass productivity reached 104.25 mg·L–1·day–1 value with 51% protein, and pigment content of 0.6% carotenoid, with 0.3% lutein. These results indicate the potential of wastewater phycoremediation at an industrial scale for the production of irrigation water and carotenoid using Muriellopsis sp.

Lutein Production and Extraction from Microalgae: Recent Insights and Bioactive Potential

“…in an 800 L raceway removed 84% of nitrogen, 93% of phosphorus, and other chemical compounds within 4 days. Biomass productivity reached 104.25 mg·L –1 ·day –1 , with 51% protein and a pigment content of 0.6% carotenoid, including 0.3% lutein [ 182 ]. Lastly, Chlorella sorokiniana TH01, cultivated in a 90 L flat-plate photobioreactor indoors, achieved the highest biomass and lutein productivity of 284–469 mg L −1 d −1 and 2.57–4.57 mg L −1 d −1 , respectively [ 183 ].…”

Environmental sustainability of microalgae-based production systems: Roadmap and challenges towards the industrial implementation

“…Correlation between areal productivity of microalgal pilot plants and annual irradiance (sunlight photoautotrophic cultivation). Data on productivity regard 18 pilot cultivation systems documented in the literature (Amorim et al, 2021;Avila et al, 2022;Barreiro-Vescovo et al, 2020;Barros et al, 2019;Cavieres et al, 2021;Haines et al, 2022;Han et al, 2020;Iamtham and Sornchai, 2022;Long et al, 2022;Masojídek et al, 2022;Mohan et al, 2021;Montalvo et al, 2019;Morillas-España et al, 2021;Plouviez et al, 2019;Rentería-Mexía et al, 2022;Sánchez Zurano et al, 2020;Sung et al, 2021;Villaró et al, 2022). When seasonal data were available, the productivity value was calculated as annual average.…”