Simultaneous chlorine decay and disinfection byproduct (DBP) formation have been discussed extensively because of their regulatory and operational significance. This study further examines chemical reaction variability in the water quality changes under various hydrodynamic conditions in drinking water distribution. The variations of kinetic constant for overall chlorine decay (k_E$k_E$) and trihalomethane (THM) formation were determined under stagnant to turbulent flows using three devices of different wall demand and two types of natural organic matters (NOM) in water. The results from the comparative experiments and modeling analyses show the relative importance of wall demand (k_w$k_w$), DBP-forming chlorine decay (k_D$k_D$), and other bulk demand ($k_b^{\text{'}}$) for pipe flows of Re = 0–52500. It is found that chlorine reactivity of virgin NOM is the overriding factor. Secondly, for tap water NOM of lower reactivity, pipe flow properties (Re or u ) can significantly affect k_E$k_E$, the THM yield (T), formation potential (Y ), and the time to reach the maximum THM concentration (t_max$t_{\max }$) through their influence on kinetic ratio $\raisebox{1ex}{$k_D$}\!\left/ \!\raisebox{-1ex}{$\left(k_b^{\text{'}}+k_w\right)$}\right.$. These observations, corroborating with turbidity variations during experiments, cannot be explained alone by chlorine dispersion to and from the pipe wall. Mass exchanges through deposition and scale detachment, most likely being flow-dependent, may have contributed to the overall chlorine decay and DBP formation rates. Thus for the simultaneous occurrence of chlorine decay and DBP formation, model considerations of NOM reactivity, pipe types (wall demand), flow hydraulics, and their interactions are essential.

同时氯衰变和消毒副产物（DBP）形成已被广泛讨论，因为它们的监管和操作意义。这项研究进一步研究了饮用水分配中各种流体动力学条件下水质变化的化学反应变异性。整体氯气衰减的动力学常数的变化（k _E${ķ}_E$）和三卤甲烷（THM）的形成是在湍流停止的情况下使用三种不同壁需求量的设备和两种水中的天然有机物（NOM）来确定的。比较实验和模型分析的结果表明，墙面需求的相对重要性（k _w${ķ}_w$），形成DBP的氯的衰减量（k _D${ķ}_d$），以及其他批量需求（${ķ}_b^{\text{'}}$），以使Re  = 0-52500的管道流量。发现原始NOM的氯反应性是主要因素。其次，对于反应性较低的自来水NOM，管道流动特性（Re或u）会显着影响k _E。${ķ}_E$，THM产量（T），形成势（Y）和达到最大THM浓度的时间（t _max${Ť}_{\mathrm{最大限度}}$）通过它们对动力学比的影响 $\raisebox{1ex}{${ķ}_d$}\!\left/ \!\raisebox{-1ex}{$（{ķ}_b^{\text{'}}+{ķ}_w）$}\right.$。这些观察结果与实验过程中的浊度变化相吻合，不能仅通过氯在管壁中的扩散和从管壁中的扩散来单独解释。通过沉积和水垢分离而进行的质量交换，很可能与流量有关，可能是导致总氯衰减和DBP形成速率的原因。因此，对于同时发生的氯气衰减和DBP形成，NOM反应性，管道类型（壁需求），流动水力及其相互作用的模型考虑至关重要。