The design, implementation and use of wastewater treatment systems (WTS) are fundamental to mitigate hydrological and environmental problems, and to improve population health. Furthermore, the significant advances in treatment systems technology offer, nowadays, several alternatives and provide many combinations of WTS which must be correctly evaluated and constitute a decision problem for public and private investors and decision makers. Thus, this article presents a multi-criteria methodology based on six steps for the evaluation of WTS considering relevant economic, social, technical and environmental criteria. Particularly, forty-eight main criteria were identified and ranked considering their importance based on the previous literature. This methodology was applied in a Brazilian sanitation company in a specific treatment area of approximately five thousand inhabitants and with recurrent environmental problems, such as the contamination and low efficiency of wastewater treatment. Twenty available alternatives were considered and twelve criteria were selected for this application. The AHP and ELECTRE II methods were combined to weight the different criteria and to rank the most suitable WTS. This methodology can be extended and applied in different scenarios to improve the decision-making process.

中文翻译：

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选择具有经济、社会、技术和环境方面的废水处理系统的多标准方法

废水处理系统 (WTS) 的设计、实施和使用对于缓解水文和环境问题以及改善人口健康至关重要。此外，如今处理系统技术的重大进步提供了几种替代方案，并提供了许多 WTS 组合，必须正确评估这些组合，并构成公共和私人投资者和决策者的决策问题。因此，本文提出了一种基于六个步骤的多标准方法，用于考虑相关的经济、社会、技术和环境标准来评估 WTS。特别是，根据先前的文献，确定了 48 个主要标准并对其重要性进行了排名。该方法被应用于巴西一家卫生公司，该公司位于一个拥有约 5000 名居民的特定处理区域，环境问题经常出现，例如污水处理的污染和低效率。考虑了 20 个可用的替代方案，并为此应用选择了 12 个标准。AHP 和 ELECRE II 方法相结合，对不同的标准进行加权并对最合适的 WTS 进行排名。这种方法可以扩展并应用于不同的场景，以改进决策过程。AHP 和 ELECRE II 方法相结合，对不同的标准进行加权并对最合适的 WTS 进行排名。这种方法可以扩展并应用于不同的场景，以改进决策过程。AHP 和 ELECRE II 方法相结合，对不同的标准进行加权并对最合适的 WTS 进行排名。这种方法可以扩展并应用于不同的场景，以改进决策过程。