The symbiotic system between Tribonema sp. and aerobic denitrifying phosphorus accumulating bacteria: A promising method for wastewater treatment

Abstract

To enhance the wastewater treatment performance of the microalgae-bacteria symbiotic system and simplify the wastewater treatment process, a strain of aerobic denitrifying phosphorus accumulating (ADPA) bacteria with simultaneous nitrification, denitrification and phosphorus removal function was isolated in this study. The strain was identified as Pseudomonas sp. Subsequently, a co-culture system of Tribonema sp. and Pseudomonas sp. (T + P) was established. Compared to the Tribonema sp.-activated sludge (T + AS), activated sludge (AS), and Pseudomonas sp. (P) groups, the T + P group exhibited excellent nitrogen and phosphorus removal efficiency. The removal efficiencies of phosphate (PO43−-P), ammonia nitrogen (NH4+-N), nitrate nitrogen (NO3−-N) and total nitrogen (TN) at 36 h were 67.69 %, 76.93 %, 95.76 % and 84.87 %, respectively. Meanwhile, T + P group had the highest total biomass and lipid content, which could reach 0.67 g·L−1 and 25.44 % in 108 h. The addition of Tribonema sp. significantly contributed to reducing total organic carbon (TOC) and inorganic carbon (IC) concentrations. This Tribonema sp.-Pseudomonas sp. symbiotic system has proven to be a promising and efficient new method for wastewater treatment, potentially addressing the limitations of traditional activated sludge processes.