Ruban G, Ruperd Y, Laveau B, Lucas E
Laboratoire Central des Ponts et Chaussées, Bouguenais, France.
Water Sci Technol. 2001;44(2-3):269-76.
Continuous pollution measurement is interesting to optimize the operation of sanitary facilities as well as to minimize the stormwater discharges. An experimental study was carried out for the determination of Suspended Solids (SS) and Chemical Oxygen Demand (COD) concentrations in combined sewers using ultraviolet and visible absorbances. The maintenance of the measurement system requires six hours a month for the cleaning of the hydraulic feeding system and adjustment of the optical device. The feeding system developed increased the representativeness and reliability of the pollution measurement, but needs to be validated on other measurement sites. The determination of SS concentrations from visible absorbances requires 2 calibration curves for dry and rainy weather respectively. The corresponding accuracies appear satisfactory when compared with the results of standard sampling/laboratory analysis. The accuracy of COD determination from ultraviolet absorbance is less satisfactory, but could perhaps be improved taking into account another parameter. Then the optical measurement of SS and COD is interesting to determine average or long term pollution loads, for example the yearly impact of urban stormwater discharges. With this kind of continuous and on-line measurement, it is possible to react with short delay to unexpected phenomena which could damage the environment or water treatment efficiency.
持续进行污染测量对于优化卫生设施的运行以及尽量减少雨水排放而言很有意义。开展了一项实验研究，以利用紫外线和可见光吸光度来测定合流制下水道中的悬浮固体（SS）和化学需氧量（COD）浓度。测量系统的维护每月需要六个小时用于清洁液压进料系统和调整光学装置。所开发的进料系统提高了污染测量的代表性和可靠性，但需要在其他测量地点进行验证。根据可见光吸光度测定SS浓度分别需要针对干燥天气和降雨天气的两条校准曲线。与标准采样/实验室分析结果相比，相应的准确度显得令人满意。通过紫外线吸光度测定COD的准确度不太令人满意，但考虑另一个参数或许可以得到改善。因此，对SS和COD进行光学测量对于确定平均或长期污染负荷很有意义，例如城市雨水排放的年度影响。通过这种连续在线测量，能够对可能破坏环境或水处理效率的意外现象迅速做出反应。
