Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Water Res. 2011 Nov 15;45(18):5997-6010. doi: 10.1016/j.watres.2011.08.053. Epub 2011 Sep 5.
The objective of wastewater treatment plants (WWTPs) is to prevent pollution. However, it is necessary to assess their sustainability in order to ensure that pollution is being removed, not displaced. In this research, the performance of 24 WWTPs has been evaluated using a streamlined Life Cycle Assessment (LCA) with Eutrophication Potential (EP) and Global Warming Potential (GWP) as environmental indicators, and operational costs as economic indicators. WWTPs were further classified in six typologies by their quality requirements according to their final discharge point or water reuse. Moreover, two different functional units (FU), one based on volume (m(3)) and the other on eutrophication reduction (kg PO(4)(3-) removed) were used to further determine sustainability. A correlation between legal requirements and technologies used to achieve them was found: Organic matter removal plants were found to be less costly both in environmental and economic terms if volume was used as the functional unit, while more demanding typologies such as reuse plants showed a trade-off between lower EP and higher cost and GWP; however, this is overcome if the second FU is used instead, proving the sustainability of these options and that this FU better reflects the objectives of a WWTP.
污水处理厂（WWTP）的目标是防止污染。然而，有必要评估其可持续性，以确保正在去除污染，而不是转移污染。在这项研究中，使用简化的生命周期评估（LCA），以富营养化潜力（EP）和全球变暖潜力（GWP）作为环境指标，以运营成本作为经济指标，对 24 个 WWTP 的性能进行了评估。根据最终排放点或水再利用的质量要求，将 WWTP 进一步分为六种类型。此外，还使用了两种不同的功能单位（FU），一种基于体积（m³），另一种基于富营养化减少（kg PO4（3-）去除），以进一步确定可持续性。发现法律要求与实现这些要求的技术之间存在相关性：如果体积用作功能单位，则有机物去除厂在环境和经济方面的成本较低，而要求较高的类型，如再利用厂，在较低的 EP 和较高的成本和 GWP 之间存在权衡；然而，如果使用第二个 FU，则可以克服这一点，证明这些选择的可持续性，并且该 FU 更好地反映了 WWTP 的目标。
