平均细胞停留时间和反硝化作用对曝气系统影响的比较经济分析

Comparative economic analysis of the impacts of mean cell retention time and denitrification on aeration systems.

作者信息

Rosso Diego, Stenstrom Michael K

机构信息

Civil and Environmental Engineering Department, University of California, Los Angeles, 5714 Boelter Hall, Los Angeles, CA 90095-1593, USA.

出版信息

Water Res. 2005 Oct;39(16):3773-80. doi: 10.1016/j.watres.2005.07.002.

DOI:10.1016/j.watres.2005.07.002

PMID:16109436

Abstract

Biological nutrient removal is practiced in various modifications of the activated sludge process (ASP) throughout the world. This paper compares conventional, nitrifying-only and combined nitrifying/denitrifying (NDN) processes. The authors performed 113 oxygen transfer efficiency measurements with the off-gas method over 20 years. This dataset was analysed and used to perform an economic analysis for three example scenarios, one for each layout (conventional, nitrifying-only and NDN). Field oxygen transfer efficiency and relevant plant operative costs and credits were considered (i.e., aeration cost, sludge disposal cost, methane production credit). The conclusion is that NDN operations always have lower aeration costs, and generally have the lowest combined operating cost. Reduced aeration costs result because of improved aeration efficiency at higher mean cell retention times and the use of nitrate as an electron acceptor. The improved aeration efficiency overcomes the increased oxygen required at higher cell retention time due to cell decay.

摘要

生物营养物去除在世界各地的活性污泥法（ASP）的各种改进工艺中得到应用。本文比较了传统工艺、仅硝化工艺和硝化/反硝化联合（NDN）工艺。作者在20年的时间里用废气法进行了113次氧转移效率测量。对该数据集进行了分析，并用于对三种示例方案进行经济分析，每种布局（传统工艺、仅硝化工艺和NDN工艺）各一个。考虑了现场氧转移效率以及相关的工厂运营成本和收益（即曝气成本、污泥处置成本、甲烷生产收益）。结论是，NDN工艺的曝气成本始终较低，且总体运营成本通常最低。曝气成本降低是因为在较高的平均细胞停留时间下曝气效率提高，以及使用硝酸盐作为电子受体。曝气效率的提高克服了由于细胞衰亡在较高细胞停留时间下所需增加的氧量。