摘要
The effects of different chemical oxygen demand(COD)concentrations on the anammox granular sludge with Bamboo Charcoal(BC)addition were evaluated in UASB reactor.The results showed that the average total nitrogen(TN)removal efficiency was reduced from 85.9%to 81.4%when COD concentration was increased from 50 to 150 mg/L.However,the TN removal efficiency of BC addition reactors was dramatically 3.1%-6.4%higher than that without BC under different COD concentrations.The average diameter of granular sludge was 0.13 mm higher than that without BC.The settling velocity was increased by elevated COD concentration,while the EPS and VSS/SS were increased with BC addition.The high-throughput Miseq sequencing analyses revealed that the bacterial diversity and richness were decreased under COD addition,and the Planctomycetes related to anammox bacteria were Candidatus Brocadia and Candidatus Kuenenia.The Metagenomic sequencing indicated that the abundance of denitrification related functional genes all increased with elevated COD,while the abundance of anammox related functional genes of decreased.The func-tional genes related to anammox was hydrazine synthase encoding genes(hzsA,hzsB and hzsB).The average relative abundance of hzs genes in the reactor with BC addition was higher than the control at COD concentrations of 50 mg/L and 150 mg/L.The functional genes of denitrification mediated by BC were higher than those without BC throughout the operation phase.It is interesting to note that BC addition greatly enriched the related func-tional genes of denitrification and anammox.
基金
supported by the China Postdoctoral Science Foundation (No. 2020M671400)
the Natural Science Foundation of Jiangsu Province (No. BK20201450)
the Jiangsu Qing Lan Project
Suzhou Science and Technology Planning Project (Nos.SS202016 and SS2019022)
the Opening Fund of Jiangsu Provincial Key Laboratory of Environmental Science and Engineering(No. Zd1804)
the Graduate Research Innovation Program of Jiangsu Province (No. KYCX19_2030)
