Maximizing nutrient removal: unveiling the influence of biomass retention time in revolving algae biofilm reactor

Environ Technol. 2024 Dec 31:1-11. doi: 10.1080/09593330.2024.2445325. Online ahead of print.

Abstract

This study introduces a novel Revolving Algae Biofilm reactor for synthetic wastewater treatment, examining the influence of various biomass retention times (BRTs) on nutrient removal performance. The study reveals complex interactions between microalgae and bacteria, emphasizing their symbiotic functions in oxygen provision, nutrient absorption, and floc creation. This research contributes to the advancement of sustainable wastewater treatment methods, showing promise for large-scale nutrient removal in industrial settings. The biomass retention time of 3 days (BRT-3) emerges as the most suitable condition for efficient nutrient removal. Specifically, in the BRT-3 period, the reactor can remove up to 97% of NH4-N, 94% of total phosphorus, and 92% of COD. NH4-N was also effectively assimilated to NO2-N and NO3-N, underscoring the efficiency of the nitrification process. While BRT-7 exhibits a noteworthy algae growth rate when it reaches the maximum rate of 3 mg/L.day. Continual investigation into the interplay between microalgae and bacteria is essential for enhancing system efficiency in future wastewater treatment applications.

Keywords: Revolving algae biofilm; biomass production; biomass retention time; nutrient removal; wastewater treatment.