Faculty of Civil and Environmental Engineering, Gdansk University of Technology, ul. Narutowicza 11/12, Gdansk, Poland.
Water Sci Technol. 2011;63(7):1418-26. doi: 10.2166/wst.2011.320.
For biological nutrient removal (BNR) systems designed to maximize nitrogen removal, the effluent total nitrogen (TN) concentration may range from 2.0 to 4.0 g N/m(3) with about 25-50% in the form of organic nitrogen (ON). In this study, current approaches to modeling organic N conversions (separate processes vs. constant contents of organic fractions) were compared. A new conceptual model of ON conversions was developed and combined with Activated Sludge Model No. 2d (ASM2d). The model addresses a new insight into the processes of ammonification, biomass decay and hydrolysis of particulate and colloidal ON (PON and CON, respectively). Three major ON fractions incorporated are defined as dissolved (DON) (<0.1 µm), CON (0.1-1.2 µm) and PON (41.2 µm). Each major fraction was further divided into two sub-fractions - biodegradable and non-biodegradable. Experimental data were collected during field measurements and lab experiments conducted at the ''Wschod'' WWTP (570,000 PE) in Gdansk (Poland). The accurate steady-state predictions of DON and CON profiles were possible by varying ammonification and hydrolysis rates under different electron acceptor conditions. With the same model parameter set, the behaviors of both inorganic N forms (NH4-N, NOX-N) and ON forms (DON, CON) in the batch experiments were predicted. The challenges to accurately simulate and predict effluent ON levels from BNR systems are due to analytical methods of direct ON measurement (replacing TKN) and lack of large enough database (in-process measurements, dynamic variations of the ON concentrations) which can be used to determine parameter value ranges.
对于旨在最大限度去除氮的生物营养物去除（BNR）系统，出水总氮（TN）浓度可能在 2.0 至 4.0 g N/m³之间，其中约 25-50%以有机氮（ON）的形式存在。在本研究中，比较了目前用于模拟有机氮转化的方法（单独的过程与有机部分的恒定含量）。开发了一种新的有机氮转化概念模型，并将其与活性污泥模型 2d（ASM2d）结合使用。该模型解决了氨化、生物量衰减以及颗粒和胶体有机氮（PON 和 CON，分别）水解过程的新见解。包含的三个主要的 ON 分数定义为溶解（DON）（<0.1 µm）、CON（0.1-1.2 µm）和 PON（41.2 µm）。每个主要分数进一步分为两个亚分数-可生物降解和不可生物降解。实验数据是在波兰格但斯克的“Wschod”污水处理厂（570,000 PE）进行现场测量和实验室实验期间收集的。通过在不同电子受体条件下改变氨化和水解速率，可以对 DON 和 CON 分布进行准确的稳态预测。使用相同的模型参数集，可以预测批处理实验中两种无机氮形式（NH4-N、NOX-N）和 ON 形式（DON、CON）的行为。准确模拟和预测 BNR 系统中出水 ON 水平的挑战是由于直接 ON 测量的分析方法（替代 TKN）和缺乏足够大的数据库（过程中的测量、ON 浓度的动态变化）所致，这些数据库可用于确定参数值范围。
