Rapid of cultivation dissimilatory perchlorate reducing granular sludge and characterization of the granulation process.

To remove high-strength perchlorate, dissimilatory perchlorate reducing granular sludge (DPR-GS) was first cultivated. Three identical UASB reactors were set up under different seed sludge and up-flow velocities (R _AS : active sludge (AS) and constant up-flow velocities; R _DGS : denitrifying granular sludge (DGS) and constant up-flow velocities; R _DGS-f : DGS and fluctuating up-flow velocities). The AS in the R _AS was completely granulated by day 117, while the DGS in the R _DGS and R _DGS-f were both shortened the granulation time to 99 days. In addition, the fluctuating up-flow velocity can better ensure rapid cultivation of DPR-GS. Removal of ClO ₄ ^- loading rate with 7.20 kg/(m ³ ·d) occurred in all three reactors. The results of extracellular polymeric substances (EPS) composition analysis indicated the polysaccharose (PS) promoted the formation of bio-aggregates, while the protein (PN) benefited the granulation of sludge. The analyses of the microbial communities indicated that Sulfurospirillum and Acinetobacter were the dominant dissimilatory perchlorate reducing bacteria.
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