Nitrogen Removal from the Simulated Wastewater of Ionic Rare Earth Mining Using a Biological Aerated Filter: Influence of Medium and Carbon Source

In engineering application, a two-stage biological aerated filter (BAF) has been deployed to achieve the steady nitrogen removal of wastewater from mining area ionic rare earth with low carbon (C/N) ratio. However, cost-efficiency medium and source casts shadow over further development. this study, influences four media (i.e., volcanic, zeolite, quartz, ceramisite) three soluble sources acetate, glucose, methanol) on N were systematically compared. Applying volcanic quartz showed favorable start-up performance due biophilic surface dense packing, respectively. regardless type, [NH4+-N]0 = 50 [NO3−-N]0 30 mg/L, C/N ratio 3 was required meet discharge standards NH4+-N, TN, COD, acetate confirmed applicable for all selected medium-packed BAFs. Introduction sweet potato residues as solid decreased amount added by more than 13%. The 16S rRNA high-throughput gene sequencing revealed that Sphingomonas Nitrospira abundant in aerobic stages zeolite-packed BAFs, Such community integrated extensively distributed Thauera, Clostridium_sensu_stricto, Proteiniclasticum anoxic stage accounted efficient removal. Thus, deploying proposed. These findings will provide valuable references selection and, consequently, optimize operational performance.