公用事业管理人员的知识差距很大 努力遵守第2阶段消毒剂/消毒 副产品规则和其他水质目标。 对于那些 已经或正在考虑从免费转换 氯气消毒。 水化学和温度会显著降低 影响氯需求和分配中的余氯 系统。镀锌铁和无衬里铸铁 管道中的氯含量很可能最低 残余沉积物，尤其是在低流量至滞流条件下 条件 本文提供了一种简化的方法 对于组合氯建模，类似于使用的 用于自由氯消散建模。 了解 机制、速率/动力学和简化的 总氯的建模和预测方法 残差将使公用事业管理人员更加舒适 对他们做出的决定充满信心 改用氯胺。包括14个参考文献、表格和图表。

A significant knowledge gap exists for utility managers struggling to comply with the Stage 2 Disinfectants/Disinfection Byproducts Rule and other water quality objectives. This is particularly true for utility managers who have switched to or are considering switching from free chlorine to combined chlorine disinfection. Water chemistry and temperature can significantly affect chlorine demand and residual chlorine in distribution systems. Galvanized-iron and unlined cast-iron pipes are most likely to experience the lowest chlorine residuals, particularly under low-flow to stagnant-flow conditions. This article provides a simplified approach for combined chlorine modeling, similar to that used for free chlorine dissipation modeling. Knowledge of the mechanisms, rates/kinetics, and a simplified approach to modeling and predicting total chlorine residuals will enable utility managers to be more comfortable and confident in decisions they make about switching to chloramines. Includes 14 references, tables, figures.