A mathematical model to plan for long-term effects of water conservation choices on dry weather wastewater flows and concentrations
A mathematical model to plan for long-term effects of water conservation choices on dry weather wastewater flows and concentrations
复制标题
用于规划节水选择对干旱天气废水流量和浓度的长期影响的数学模型
DOI：
10.1016/j.jenvman.2017.10.013
复制
发表时间：
2018
影响因子：
8.7
通讯作者：
VanBriesen, Jeanne M.
中科院分区：
文献类型：
--
作者：
Cook, Lauren M.;Samaras, Constantine;VanBriesen, Jeanne M.
在许多城市，下水道系统正在经历与设计时显著不同的情况。节约用水、人口变化和减少渗漏等因素正在改变污水的数量和质量。这些变化可能会影响下水道保持自洁速度的能力，这对避免固体沉降和腐蚀问题至关重要。此外，这样的变化可能会改变预期的污水处理厂扩建的时间表。本文提出了一种预测年平均干季污水流量以及随时间变化的污染物负荷和浓度的方法。该方法考虑了由于节水和再利用措施可能导致的人均废水产生量的下降，以及其他潜在的变化，如人口转移、工业废水产生量的变化以及干旱天气入渗的变化。结果表明，干旱天气的入渗量将在保育是否会影响自净速度或植物扩张方面发挥很大作用。由于可以避免工厂扩建，因此对于干旱天气渗入水平较高的系统最有利；对于渗入水平较低的系统最不利，因为低流量条件可能会导致下水道中的沉降和腐蚀。此外，保护工作的实施速度影响着何时会对系统产生影响。公用事业规划者将能够使用这种方法更准确地预测处理厂的升级和扩建需求，以及评估以公用事业为基础的维护活动和保护做法的相对价值。
In many cities, sewer systems are experiencing conditions that are significantly different from those for which they were designed. Factors such as water conservation efforts, changes in population, and efforts to reduce infiltration are altering the quantity and quality of sewage. These changes may affect the ability of sewers to maintain self-cleansing velocities, which are crucial to avoiding solids settling and corrosion issues. Further, such changes may alter the timeline for expected wastewater plant expansion. The present work proposes a method for predicting average annual dry weather wastewater flow, as well as pollutant load and concentration over time. The method takes into account potential declines in per person wastewater production due to water conservation and reuse practices, as well as other potential changes such as shifts in population, transformations in industrial wastewater production, and variations in dry weather infiltration. Results show that the amount of dry weather infiltration will play a large role in whether or not conservation will affect self-cleansing velocities or plant expansions. Conservation is most beneficial to systems with high levels of dry weather infiltration since plant expansion could be avoided; and most detrimental to systems with low levels of infiltration since low flow conditions could lead to settling and corrosion in the sewer. Furthermore, the rate of implementation of conservation efforts influences when impacts to the system would occur. Utility planners will be able to use this method to predict treatment plant upgrade and expansion needs more accurately as well as to assess the relative value of utility-based maintenance activities and conservation practices.