Synergistic enhancement of UASB reactor for leachate treatment using Fe2O3 nanomodified pumice and ozone oxidation.

[Display omitted] • Fe 2 O 3 Nanomodified Pumice was synthesized by hydrothermal method. • Coupling Ozonation and modified pumice enhanced UASB was firstly applied to the treatment of landfill leachates. • Ozonation and Fe 2 O 3 Nanomodified Pumice make the start-up time of the reactor accelerated. • UASB process achieved efficient COD (93%) removal and methane productivity (58.23 d/L) Pumice, a material with good application prospects in adsorption and water treatment, has less research on its improvement. In this study, the positive benefits of anaerobic reaction were explored by loading iron oxide on pumice and combined with ozone advanced oxidation. In the experiment, the Upflow Anaerobic Sludge Blanket (UASB) reactor was enhanced with pretreatment from an ozone generator (6 L/min flow rate, delivering 500 ± 5 % mg/L of ozone) and the addition of 250 ml of Fe 2 O 3 Nanomodified Pumice (FP). The results showed that FP could play an active role in the formation of sludge particles. The addition of FP increased the level of interspecies electron transfer (DIET), improved the reaction of hydrolysis and acid production, methane production and the activity of dominant species. At the same time, the advanced oxidation of ozone and the improvement of FP on the decomposition ability avoid the accumulation of macromolecular volatile fatty acids and reduce the risk of reactor acidification. At the microbial level, the addition of FP better promoted the correlation between the three dominant strains of Firmicutes, Synergistota, and Desulfobacteriota, and promoted the connection between the reactions. Under these promoting effects, not only the start-up time of the reactor was accelerated, but also the anti-load capacity was improved, and the reactor could maintain a removal rate of more than 90 % at an organic load of 53.89 kgCOD / (m3 · d). [ABSTRACT FROM AUTHOR]