文献类型：期刊文献

英文题名：Application of acidic conditions and inert-gas sparging to achieve high-efficiency nitrous oxide recovery during nitrite denitrification

作者：Zhuge, Yang-yang[1,2];Shen, Xun-yu[1,2];Liu, Yong-di[1,2,3];Shapleigh, James[4];Li, Wei[1,2]

机构：[1]East China Univ Sci & Technol, Sch Resources & Environm Engn, Natl Engn Lab Ind Wastewater Treatment, Shanghai, Peoples R China;[2]East China Univ Sci & Technol, Sch Resources & Environm Engn, State Environm Protect Key Lab Environm Risk Asse, Shanghai, Peoples R China;[3]Shanghai Inst Pollut Control & Ecol Secur, Shanghai, Peoples R China;[4]Cornell Univ, Dept Microbiol, Ithaca, NY USA

年份：2020

卷号：182

外文期刊名：WATER RESEARCH

收录：;EI(收录号：20202408833281);WOS:【SCI-EXPANDED(收录号:WOS:000569155400001)】；

基金：This work was supported by National Natural Science Foundation of China (51808223), Fundamental Research Funds for the Central Universities (222201814053, 222201817009), and Shanghai Educational Development Foundation (18CG34).

语种：英文

外文关键词：Biological nitrogen removal; Energy recovery; Nitrous oxide; Sparging in acidic condition; Meta-omics

摘要：Nitrogen removal with energy recovery through denitrification dependent N2O production is garnering recent attention due to its cost advantages. The most effective current method requires alternating COD and nitrite to achieve high N2O production making it incompatible with typical wastewaters and consequently difficult to use in most settings. The work described here introduces a robust and highly efficient N2O recovery approach which has the potential to work with wastewaters containing COD and nitrite simultaneously. This method relies on low pH incubation and inert gas sparging (IGS) to shift a community of mainly N-2 producing nitrite denitriflers to a community that accumulates N2O when incubated in the absence of IGS. Before experiencing IGS, samples from activated sludge incubated at a pH of 4.5 and 6.0 only achieved a maximum N2O production efficiency (PE_N2O) of similar to 26%. After IGS the PE_N2O values increased to similar to 97.5% and similar to 80.2% for samples from these same pH 4.5 and pH 6.0 reactors, respectively. IGS did not lead to N2O production in a pH 7.5 bioreactor. Meta-omics analysis revealed that IGS resulted in an increase in bacteria utilizing the Glade I nitrous oxide reductase (nosZ(I)) relative to bacteria utilizing the Glade II nitrous oxide reductase (nosZ(II)). This likely results from IGS flushing out N2O leaving nitrite as the principal nitrogen oxide available for respiration, favoring nosZ(I) utilizing bacteria which are more likely to be complete denitriflers. Metatranscriptomic analysis suggested that the high PE_N2O values that occurred after stopping IGS result from the NO generated by chemodenitrification accumulating to levels that inactivate [4Fe:4S] clusters in the NosR protein essential for N2O reduction in the nosZ(I) denitriflers. This study provides an efficient and straightforward method for N2O recovery, widening the options for energy recovery from nitrogen-based wastes. (C) 2020 Elsevier Ltd. All rights reserved.