Algae-constructed wetland integrated system for wastewater treatment: A review

• Published in: Bioresource technology 2024-08, Vol.406, p.131003, Article 131003
• Main Authors: Bang Truong, Hai, Nguyen, T. Hong Tinh, Ba Tran, Quoc, Son Lam, Vinh, Thao Nguyen Nguyen, T., Cuong Nguyen, Xuan
• Format: Article
• Language: English
• Subjects: Bioremediation; Ecological engineering; Nutrient removal; Organic load reduction; Sewage
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2024.131003

[Display omitted] •Detailed insights into algae-CW interactions and their mechanisms are provided.•The role of algae in nitrogen purification was confirmed; other effects varied.•The average removal rates were 74–75 % for COD, NH4+-N, and TN and 79 % for TP.•COD and TP removal rates improved by approximately 0.6 % every 10 days.•This review identifies challenges and proposes future directions for enhancements. Integrating algae into constructed wetlands (CWs) enhances wastewater treatment, although the results vary. This review evaluates the role of algae in CWs and the performance of different algae-CW (A-CW) configurations based on literature and meta-analysis. Algae considerably improve N removal, although their impact on other parameters varies. Statistical analysis revealed that 70 % of studies report improved treatment efficiencies with A-CWs, achieving average removal rates of 75 % for chemical oxygen demand (COD), 74 % for total nitrogen and ammonium nitrogen, and 79 % for total phosphorus (TP). This review identifies hydraulic retention times, which average 3.1 days, and their varied impact on treatment efficacy. Mixed-effects models showed a slight increase in COD and TP removal efficiencies of 0.6 % every ten days in the A-CWs. Future research should focus on robust experimental designs, adequate algal storage and separation techniques, and advanced modeling to optimize the treatment potential of algae in CWs.