Capability of microalgae-based wastewater treatment systems to remove emerging organic contaminants: a pilot-scale study
Open accessAbstract
The effect of hydraulic retention time (HRT) and seasonality on the removal efficiency of 26 organic microcontaminants from urban wastewater was studied in two pilot high-rate algal ponds (HRAPs). The targeted compounds included pharmaceuticals and personal care products, fire retardants, surfactants, anticorrosive agents, pesticides and plasticizers, among others. The pilot plant, which was fed at a surface loading rate of 7-29 g of COD m(-2)d(-1), consisted of a homogenisation tank and two parallel lines, each one with a primary settler and an HRAP with a surface area of 1.5 m(2) and a volume of 0.5 m(3). The two HRAPs were operated with different HRTs (4 and 8 d). The removal efficiency ranged from negligible removal to more than 90% depending on the compound. Microcontaminant removal efficiencies were enhanced during the warm season, while the HRT effect on microcontaminant removal was only noticeable in the cold season. Our results suggest that biodegradation and photodegradation are the most important removal pathways, whereas volatilization and sorption were solely achieved for hydrophobic compounds (log Kow>4) with a moderately high Henry's law constant values (11-12 Pa m(-3)mol(-1)) such as musk fragrances. Whereas acetaminophen, ibuprofen and oxybenzone presented ecotoxicological hazard quotients (HQs) higher than 1 in the influent wastewater samples, the HQs for the effluent water samples were always below 1.
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Microalgae capture both cationic and anionic species of heavy metals because they have a large number of deprotonated carboxyl and sulfate groups as well as monomeric alcohols that stimulate biosorption.
“Microalgae capture both cationic and anionic species of HMs because they have a large number of deprotonated carboxyl and sulfate groups as well as monomeric alcohols that stimulate biosorption [80].”
From Microalgae-based wastewater treatment: Mechanisms, challenges, recent advances, and future prospects (2023) · cites this paper as [80]
The Introduction says microalgae-based wastewater systems have been studied for heavy-metal removal. It does not say they capture both cationic and anionic species or attribute biosorption to deprotonated carboxyl and sulfate groups or monomeric alcohols. Section 3.2 discusses sorption to microalgal biomass, but for hydrophobic organic contaminants, not heavy metals. (LLM, conf=0.84)
Experimental — accuracy not yet measuredChlorella sp. and Spirulina (Arthrospira) sp. can treat many types of wastewaters, including municipal, aquaculture, swine, olive oil milling, distillery, confectionary, brine tapioca, tofu, rubber, paper mill, dye wastewaters, agricultural run-offs, and groundwaters.
“Many examples of wastewater treatment by Chlorella sp. and Spirulina (Arthrospira) sp. have been published, as these can treat many types of wastewaters, including municipal, aquaculture, swine, olive oil milling, distillery, confectionary, brine tapioca, tofu, rubber, paper mill, dye wastewaters, agricultural run-offs, and groundwaters [203,209,210,211,212].”
From Emerging Applications of Chlorella sp. and Spirulina (Arthrospira) sp. (2023) · cites this paper as [212]
Section 2.2 (lines 105–115) describes a pilot system treating urban wastewater, and Section 3.1 (lines 199–203) identifies Chlorella sp. among its predominant algae. The paper does not establish that Spirulina treats wastewater or support the claim’s extensive list of wastewater types. (LLM, conf=0.85)
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- Authors
- Matamoros, V., Gutiérrez, R., Ferrer, I., García, J., & Bayona, J. M.
- Affiliations
- Consejo Superior de Investigaciones Científicas (ES)
- Universitat Politècnica de Catalunya (ES)
- Corresponding author
- Matamoros, Víctor
- Venue
- Journal of Hazardous Materials
- Publisher
- Elsevier BV
- Published
- 2015-05
- Volume
- 288
- Pages
- 34-42
- ISSN
- 0304-3894 (ISSN-L)
- OpenAlex
- W2000356805
- Cited by
- 466
- References
- 59
- Citations by year
- 2026: 22 · 2025: 33 · 2024: 60 · 2023: 51 · 2022: 54 · 2021: 59 · 2020: 58 · 2019: 44 · 2018: 26 · 2017: 29 · 2016: 26 · 2015: 4
- FWCI
- 17.59
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Journal of Hazardous Materials (publishedVersion)
- PubMed (publishedVersion)
- LA Referencia (Red Federada de Repositorios Institucionales de Publicaciones Científicas) (publishedVersion, cc-by-nc-nd)
- UPCommons institutional repository (Universitat Politècnica de Catalunya) (publishedVersion, cc-by-nc-nd)
- DIGITAL.CSIC (Spanish National Research Council (CSIC)) (submittedVersion)
- RECERCAT (Consorci de Serveis Universitaris de Catalunya) (submittedVersion, cc-by-nc-nd)
- Funders
- Spanish Ministry of Economy and Competitiveness through projects (CTM2012-33547, CTM2012-37860)
- Topics
- Physical Sciences › Environmental Science › Pollution › Pharmaceutical and Antibiotic Environmental Impacts
- Physical Sciences › Environmental Science › Waste Management and Disposal › Constructed Wetlands for Wastewater Treatment
- Physical Sciences › Environmental Science › Waste Management and Disposal › Wastewater Treatment and Reuse
- Keywords
- microalgae-based wastewater treatment, high rate algal ponds, emerging organic contaminants, hydraulic retention time, seasonal variation, pharmaceuticals and personal care products, flame retardants, surfactants, pesticides, plasticizers, biodegradation, photodegradation, volatilization, sorption, musk fragrances, paracetamol, ibuprofen, benzophenone-3, municipal wastewater
- MeSH terms
- Algorithms, Biodegradation, Environmental, Cosmetics, Pharmaceutical Preparations, Organic Chemicals, Pilot Projects, Seasons, Waste Disposal, Fluid, Water Pollutants, Chemical, Water Purification, Microalgae
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