Biological floating bed and bio-contact oxidation processes for landscape water treatment: simultaneous removal of Microcystis aeruginosa, TOC, nitrogen and phosphorus

The aim of this study was to identify algicidal bacteria J25 against the Microcystis aeruginosa (90.14%), Chlorella (78.75%), Scenedesmus (not inhibited), and Oscillatoria (90.12%). Meanwhile, we evaluate the SOD activity and efficiency of denitrification characteristics with Acinetobacter sp. J25. A novel hybrid bioreactor combined biological floating bed with bio-contact oxidation (BFBO) was designed for treating the landscape water, and the average removal efficiencies of nitrate-N, ammonia-N, nitrite-N, TN, TP, TOC, and algal cells were 91.14, 50, 87.86, 88.83, 33.07, 53.95, and 53.43%, respectively. A 454-pyrosequencing technology was employed to investigate the microbial communities of the BFBO reactor samples. The results showed that Acinetobacter sp. J25 was the dominant contributor for effective removal of N, algal cells, and TOC in the BFBO reactor. And the relative abundance of Acinetobacter showed increase trend with the delay of reaction time.