Abstract Improving eco-efficiency of wastewater treatment plants (WWTPs) has been identified as being essential for achieving urban sustainability. Several previous papers have evaluated the eco-efficiency of WWTPs using data envelopment analysis (DEA) models. However, those models provided only a static assessment in that they ignored possible fluctuations over time within each plant. To overcome this temporal limitation, this paper evaluates dynamic eco-efficiency (changes in eco-productivity over time) of WWTPs using the dynamic weighted Russell directional distance model (WRDDM). This approach allows one to obtain an eco-productivity change index for each major component of the WRDDM model (costs, pollutants removal, and greenhouse gas emissions). Our results illustrate that although eco-productivity improved in half of the WWTPs we assessed, there was still potential for improving some eco-efficiency components. Moreover, operational costs and greenhouse gases emissions were the main drivers reducing eco-productivity. This paper demonstrates the importance of evaluating change in eco-productivity over time and in identifying the drivers associated with those changes, both of which can be used to support decision-making focused on the sustainability of WWTPs.

中文翻译：

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评估污水处理厂生态生产力的变化：成本、污染物去除效率和温室气体排放的作用

摘要 提高污水处理厂 (WWTP) 的生态效率已被确定为实现城市可持续性的必要条件。之前的几篇论文已经使用数据包络分析 (DEA) 模型评估了污水处理厂的生态效率。然而，这些模型仅提供静态评估，因为它们忽略了每个工厂内随时间可能发生的波动。为了克服这种时间限制，本文使用动态加权罗素方向距离模型 (WRDDM) 评估污水处理厂的动态生态效率（生态生产力随时间的变化）。这种方法允许获得 WRDDM 模型每个主要组成部分（成本、污染物去除和温室气体排放）的生态生产力变化指数。我们的结果表明，虽然我们评估的一半污水处理厂的生态生产力有所提高，在某些生态效率方面仍有改进的潜力。此外，运营成本和温室气体排放是降低生态生产力的主要驱动因素。本文展示了评估生态生产力随时间的变化以及确定与这些变化相关的驱动因素的重要性，这两者都可用于支持专注于污水处理厂可持续性的决策。