Even though aerobic methane-oxidation coupled to denitrification (AME-D) has been extensively studied, the exact estimation of CH₄ utilization during this process still requires better understanding because effective utilization of CH₄ is essential in denitrification performance, CH₄ emission and economy. This study presents the effect of hydraulic retention time (HRT) on CH₄ utilization in an AME-D bioreactor. Stoichiometries for AME-D were newly established by using the energy balance and the thermodynamic electron equivalent model. The theoretically determined CH₄ utilized/NO₃⁻ consumed (C/N) ratio from the stoichiometry was 2.0. However, the C/N ratios obtained from the experiment varied with increasing tendency as the HRT increased. Specifically, the C/N ratio increased from 1.38 to 2.85 when the HRT increased from 0.5 to 1.0 days, which placed the theoretical C/N ratio at the HRT between 0.5 and 1.0 days. The higher C/N ratio at the longer HRT was associated with a larger CH₄ utilization by methanotrophs than denitrifiers. The results obtained in this study together with those obtained in previous studies clearly illustrated that a variety of conditions affect the utilization of CH₄ which is essential for optimizing the AME-D process.

中文翻译：

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需氧甲烷氧化与反硝化（AME-D）结合使用的甲烷：理论估算和水力停留时间（HRT）的影响。

尽管对好氧甲烷氧化与反硝化（AME-D）进行了广泛研究，但在此过程中对CH ₄利用率的准确估算仍需要更好地理解，因为有效利用CH ₄对于反硝化性能，CH ₄排放和经济性至关重要。 。这项研究提出了水力停留时间（HRT）对AME-D生物反应器中CH ₄利用率的影响。通过使用能量平衡和热力学电子当量模型，新建立了AME-D的化学计量。理论上确定的CH ₄利用/ NO ₃ ^-化学计量的消耗（C / N）比为2.0。然而，随着HRT的增加，从实验中获得的C / N比随着趋势的增加而变化。具体而言，当HRT从0.5天增加到1.0天时，C / N比从1.38增加到2.85，这将HRT的理论C / N比置于0.5天和1.0天之间。HRT较长时，较高的C / N比与甲烷（比反硝化器）对CH _4的利用更大。在本研究中获得的结果以及在先前研究中获得的结果清楚地说明，各种条件都会影响CH ₄的利用，这对于优化AME-D工艺至关重要。