A consilience model to describe N₂O production during biological N removal

Abstract

A mathematical model congruent with the current understanding of the biological processes occurring during wastewater treatment operations is proposed.Please check this proof carefully. Our staff will not read it in detail after you have returned it.Translation errors between word-processor files and typesetting systems can occur so the whole proof needs to be read. Please pay particular attention to: tabulated material; equations; numerical data; figures and graphics; and references. If you have not already indicated the corresponding author(s) please mark their name(s) with an asterisk. Please e-mail a list of corrections or the PDF with electronic notes attached -do not change the text within the PDF file or send a revised manuscript. Corrections at this stage should be minor and not involve extensive changes. All corrections must be sent at the same time.Please bear in mind that minor layout improvements, e.g. in line breaking, table widths and graphic placement, are routinely applied to the final version.Please note that, in the typefaces we use, an italic vee looks like this: n, and a Greek nu looks like this: ν.We will publish articles on the web as soon as possible after receiving your corrections; no late corrections will be made.Please return your final corrections, where possible within 48 hours of receipt, by e-mail to: eswater@rsc.org Queries for the attention of the authors Q3The sections have been renumbered so that they appear in numerical order. Please check that this is correct. Q4The sentence beginning "Second, the true…" has been altered for clarity, please check that the meaning is correct. Q5In the sentence beginning "The actual concentrations…", please check that all of the characters are presented correctly. Q6Ref

Genome-Scale, Constraint-Based Modeling of Nitrogen Oxide Fluxes during Coculture of Nitrosomonas europaea and Nitrobacter winogradskyi

“…To date, most genome-scale and metabolic models of nitrification have focused on biotic reactions (17, 22, 23, 36). While this approach simplifies the construction of models, it neglects the importance of abiotic chemistry in the N cycle (13).…”

“…The magnitude of nitrifier-derived emissions of N oxides generated by nitrification from soils and engineered environments are extremely variable and depend on a variety of environmental conditions such as the rate of nitrification, pH, temperature, and oxygen (O 2 ), among other factors (4, 13, 18–21). Recent modeling efforts by Perez-Garcia et al and others have sought to understand conditions that generate N oxides through single and multispecies metabolic network models of wastewater treatment systems (17, 22–24). Modeling N oxide production by simplified communities of model nitrifiers in both single culture and coculture, including abiotic reactions, can expand on previous work to better explain the mechanisms and conditions that affect N oxide gas emissions.…”

Organic carbon recovery modeling for a rotating belt filter and its impact assessment on a plant-wide scale

“…Likewise, the AD is framed using the widely used anaerobic digestion model no 1 (ADM1) [25]. Further to extend the study of carbon recovery impact on N 2 O emission, two different models (as shown in Figure 8 ) are considered which are extension of Hiatt and Grady [26], Guo and Vanrolleghem [27] and Domingo-Félez and Smets [28]. For additional details on design and operating conditions, the reader is referred to the papers by Gernaey et al [18] and Jeppsson et al [19].…”

“…In oder to understand the impact of carbon recovery (by RBF and PC) on N 2 O gas emission, the ASM1 model is extended (to incorporate the one pathway and two pathway model separately) based on the understanding from Hiatt and Grady [26], Guo and Vanrolleghem [27] and Domingo-Félez and Smets [28]. In this section, it is important to note that these N 2 O models are only used to generate N 2 O emission data for the discussion section in the results (see the Table 7).…”

“…Therefore two alternative models (as shown in Figure 8) are used to verify the impact of organic carbon recovery on nitrous oxide (N 2 O) emission which is an important greenhouse gas with global warming potential equivalent to 300 times the global warming potential of carbon dioxide. In a WWTP, the N 2 O can be produced both in the denitrification process (heterotrophic bacteria (HB) are the key players) and the nitrification process (where AOB are the main contributors) [20,28,32,33]. The pathways/models [26] for the N 2 O production from the denitrification process are straightforward…”