McIlhatton T D, Sakrabani R, Ashle R M, Burrows R
Department of Civil Engineering, University of Liverpool, UK.
Water Sci Technol. 2002;45(3):61-9.
The problems associated with solids in sewerage systems result in common difficulties such as blockages and flooding and the subsequent maintenance requirements have been well documented. Concerns regarding pollutant release have also been demonstrated, with the contribution from in-sewer solids to the quality of the flow during a storm event being especially significant. These events known as "foul flushes" in combined sewers typically occur in the initial period of storm flows, when the concentration of suspended sediments and other pollutants are significantly higher than at other times. Traditionally impacts from these events have been related to the suspended solids phase of the flow passing through a CSO structure. It is now apparent that much of the suspended load originates from solids eroded from the bed. The "near bed solids" which are re-entrained into the flow, together with solids eroded from the bulk bed, account for large changes in the suspended sediment concentration under time varying flow conditions. The influence of these eroded solids and their potential impact on receiving waters and treatment plants will be reviewed using data obtained from field studies carried out in the main Dundee interceptor sewer in Scotland. This paper describes some of the methods employed to investigate the characteristics of the pollutants associated with solids erosion in combined sewers.
污水系统中的固体物质带来了诸如堵塞和洪水等常见问题，后续的维护需求也有详尽记录。人们也已证实对污染物排放的担忧，尤其是在暴雨事件中，污水中的固体物质对水流质量的影响尤为显著。在合流制下水道中，这些被称为“污水冲刷”的事件通常发生在暴雨径流的初始阶段，此时悬浮沉积物和其他污染物的浓度显著高于其他时段。传统上，这些事件的影响与通过合流制溢流（CSO）结构的水流中的悬浮固体相有关。现在很明显，大部分悬浮负荷源自河床侵蚀产生的固体物质。重新卷入水流中的“近河床固体物质”，以及从河床主体侵蚀而来的固体物质，在随时间变化的水流条件下，导致了悬浮沉积物浓度的大幅变化。将利用在苏格兰邓迪主要截流下水道进行的现场研究获得的数据，来评估这些侵蚀固体物质的影响及其对受纳水体和处理厂的潜在影响。本文介绍了一些用于研究合流制下水道中与固体侵蚀相关污染物特性的方法。
