Analysis of the Application of Bioreactors in the Nitrogen Removal from Industrial Effluents

Objective: To analyze the most efficient methods for nitrogen removal from industrial effluents using bioreactors and microalgae-based systems, based on scientific publications indexed in the Scopus database between 2014 and 2024. Method: This is a systematic review of descriptive and exploratory nature, with a qualitative approach, conducted following the PRISMA method guidelines. Filters for language, document type, and time period were applied, resulting in the inclusion of 10 articles. Results and Discussion: The studies indicated that systems based on anammox, combined with partial nitritation or partial denitrification, showed the best performance, with efficiencies above 90%, especially in granular or multiphase reactors operating under low C/N ratios. The choice of method is strongly associated with the characteristics of the effluent, such as salinity, temperature, and volume. Stability and strict parameter control were highlighted as critical factors for treatment success. Research Implications: The study reinforces the importance of compatibility between the system and the effluent, indicating that hybrid and multistage approaches are promising for treating complex effluents while ensuring efficiency, stability, and operational sustainability. Originality/Value: The study provides an updated synthesis of the most effective practices for nitrogen removal in industrial effluents, highlighting technological solutions with high applicability potential, even under challenging conditions, and serving as a reference for future projects and research.