Nitrous oxide emissions for early warning of biological nitrification failure in activated sludge

WATER RESEARCH

卷:43

Article

Butler, M. D.^2,4  Wang, Y. Y.³  Cartmell, E.¹  Stephenson, T.¹ 

[1] Cranfield Univ, Cranfield MK43 0AL, Beds, England

[2] So Water, Chatham ME5 7QA, Kent, England

[3] Tongji Univ, Sch Environm Sci & Engn, Shanghai 200092, Peoples R China

[4] Water Innovate Ltd, CUBIC, Cranfield MK43 0AL, Beds, England

关键词: Activated sludge;    Early warning;    Nitrification;    Nitrous oxide;    Toxic shocks;   

DOI  :  10.1016/j.watres.2008.12.027

来源: Elsevier

【 摘 要 】

Experiments were carried out to establish whether nitrous oxide (N2O) could be used as a non-invasive early warning indicator for nitrification failure. Eight experiments were undertaken; duplicate shocks DO depletion, influent ammonia increases, allylthiourea (ATU) shocks and sodium azide (NaN3) shocks were conducted on a pilot-scale activated sludge plant which consisted of a 315 L completely mixed aeration tank and 100 L clarifier. The process performed well during pre-shock stable operation; ammonia removals were up to 97.8% and N2O emissions were of low variability (<0.5 ppm). However, toxic shock loads produced an N2O response of a rise in off-gas concentrations ranging from 16.5 to 186.3 ppm, followed by a lag-time ranging from 3 to 5 h ((0.43-0.71) x HRT) of increased NH3-N and/or NO2- in the effluent ranging from 3.4 to 41.2 mg L-1. it is this lag-time that provides the early warning for process failure, thus mitigating action can be taken to avoid nitrogen contamination of receiving waters. (C) 2008 Elsevier Ltd. All rights reserved.

【 授权许可】

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