Clarifying the Role of Phosphorus Management Strategies in Enhancing the Sustainability of Wastewater Treatment Plants

Abstract

With the emphasis on climate change and society’s goals of carbon neutrality, wastewater treatment plants (WWTPs) are facing new challenges to be more sustainable and particularly to reduce their greenhouse gas (GHG) emissions. In addition, the increasingly stringent discharge standard, especially the phosphorus removal target, also puts lots of pressure on WWTPs. The key solution is to tailor and/or optimize the phosphorus management strategies to balance removal targets and sustainability. As such, the present study systematically summarizes and analyzes different phosphorus management approaches and their impacts on the costs and operation of whole plants. The summary shows that precipitate scaling is a common issue that can be alleviated by proper phosphorus management strategies and operation optimization. Biological phosphorus removal and chemical phosphorus removal processes have their respective advantages and disadvantages. Most importantly, each phosphorus removal process probably has countering impacts on wastewater and sludge treatment lines. Thus, the evaluation of a specific phosphorus removal process should consider all factors in choosing a suitable technology, which is also true for phosphorus recovery, and the recovery from incineration ash seems to be a trend that is more feasible from a regulatory perspective.