ABSTRACT

This paper presents a methodology to estimate free residual chlorine concentrations (FRCC) in full-scale water distribution system (WDS) using different degradation kinetics according to pipe material, age and diameter. Intensive field sampling campaigns and laboratory-scale tests were carried out to estimate total and bulk volume FRCC in three WDS. Bulk kinetic constants were estimated for water temperatures typical of different seasons in the Quebec City area (Canada). With field-measured FRCC at all sampling sites and an estimation of travel times through the use of a hydraulic model, total, bulk and pipe wall kinetic constants were obtained with ranges of 10.2 to 130.4, 4.1 to 43.8 and 8.5 to 114.9 10⁻³/h, respectively. Pipe wall kinetics tend to dominate the total degradation process for older grey and ductile cast-iron pipes, followed by newer ductile iron pipes and then PVC and pre-stressed concrete pipes (mostly installed from 1990). The developed methodology and results will be useful to improve the prediction of FRCC through hydraulic and water quality modelling.

摘要

本文介绍了一种根据管道材料、使用年限和直径使用不同降解动力学估算全尺寸配水系统 (WDS) 中游离残留氯浓度 (FRCC) 的方法。进行了密集的现场采样活动和实验室规模的测试，以估计三个 WDS 中的总体积和大体积 FRCC。针对魁北克市地区（加拿大）不同季节的典型水温估算了体积动力学常数。使用在所有采样点现场测量的 FRCC 和通过使用水力模型估计行进时间，获得了范围为 10.2 至 130.4、4.1 至 43.8 和 8.5 至 114.9 10 ^{-3 的}总、体积和管壁动力学常数/h，分别。管壁动力学往往在旧的灰铸铁管和球墨铸铁管的总降解过程中占主导地位，其次是较新的球墨铸铁管，然后是 PVC 和预应力混凝土管（大部分安装于 1990 年）。开发的方法和结果将有助于通过水力和水质建模改进 FRCC 的预测。