Total and stable washout of nitrite oxidizing bacteria from a nitrifying continuous activated sludge system using automatic control based on Oxygen Uptake Rate measurements
Total and stable washout of nitrite oxidizing bacteria from a nitrifying continuous activated sludge system using automatic control based on Oxygen Uptake Rate measurements
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DOI：
10.1016/j.watres.2009.03.022
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发表时间：
2009-06-01
期刊：
影响因子：
12.8
通讯作者：
Carrera, Julian
中科院分区：
文献类型：
--
作者：
Jubany, Irene;Lafuente, Javier;Carrera, Julian
近年来，部分硝化作用（铵氧化为亚硝酸盐）在研究人员中引起了广泛关注，因为相较于完全硝化作用（铵氧化为硝酸盐）它具有诸多优势：硝化作用需氧量降低，反硝化过程中化学需氧量需求以及二氧化碳排放量减少，缺氧生长过程中反硝化速率更高且生物量产生更低。在本研究中，一种超高浓度铵废水（3000 - 4000毫克氮/升）在一个连续中试装置中进行处理，该装置由三个串联的反应器和一个沉淀池组成。该系统在尽可能高的体积氮负荷率下运行，温度适中（约25℃），污泥停留时间较长（约30天），硝化生物量浓度较高（平均为1800 ± 600毫克挥发性悬浮固体/升）。所实施的控制回路将原本进行完全硝化的系统转变为一个连续的部分硝化系统。通过针对pH值和溶解氧（DO）的局部控制回路，并设定适当的抑制亚硝酸盐氧化菌（NOB）的设定值（pH = 8.3以及DO = 1.2 - 1.9毫克O₂/升），以及一个基于耗氧速率（OUR）测量的进水控制回路，实现了亚硝酸盐氧化菌的淘汰，这使得中试装置在任何时刻都能以最大的铵氧化能力运行。这种操作策略使氨氧化菌（AOB）和亚硝酸盐氧化菌的生长速率差异最大化，这是实现快速且稳定地淘汰亚硝酸盐氧化菌的关键。结果表明，部分硝化系统稳定运行了100多天，并且通过荧光原位杂交（FISH）分析证实了亚硝酸盐氧化菌被淘汰。（C）2009爱思唯尔有限公司。保留所有权利。
Partial nitrification (ammonium oxidation to nitrite) has gained a lot of interest among researchers in the last years because of its advantages with respect to complete nitrification (ammonium oxidation to nitrate): decrease of oxygen requirements for nitrification, reduction of COD demand and CO2 emissions during denitrification and higher denitrification rate and lower biomass production during anoxic growth.In this study, an extremely high-strength ammonium wastewater (3000-4000 mg N L-1) was treated in a continuous pilot plant with a configuration of three reactors in series plus a settler. The system was operated under the maximum possible volumetric nitrogen loading rate, at mild temperature (around 25 degrees C), with high sludge retention time (around 30 d) and significant nitrifying biomass concentration (average of 1800 +/- 600 mg VSS L-1). The implemented control loops transformed the system, which was operating with complete nitrification, into a continuous partial nitrification system. Nitrite oxidizing bacteria (NOB) washout was accomplished with local control loops for pH and dissolved oxygen (DO) with proper setpoints for NOB inhibition (pH = 8.3 and DO = 1.2-1.9 Mg O-2 L-1) and with an inflow control loop based on Oxygen Uptake Rate (OUR) measurements, which allowed working at the maximum ammonium oxidation capacity of the pilot plant in each moment. This operational strategy maximized the difference between ammonia oxidizing bacteria (AOB) and NOB growth rates, which is the key point to achieve a fast and stable NOB washout. The results showed a stable operation of the partial nitrification system during more than 100 days and NOB washout was corroborated with fluorescence in-situ hybridization (FISH) analysis. (C) 2009 Elsevier Ltd. All rights reserved.