Wastewater and Reclaimed Water Reuse for Achieving Water Circularity

The worldwide expansion of human population has led to unprecedented stress on the freshwater sources especially in the developing countries with extreme climatic conditions. In light of the costs incurred in step up of supply systems, the wastewater generated from various sources is now beginning to be perceived as a resource rather than a nuisance. The reclaimed water can be used for landscape irrigation, agriculture, non-potable activities and industrial purposes and environmental applications like groundwater replenishment and may reduce the water footprint considerably. The degree of treatment of wastewater would depend upon the intended application and selection of appropriate combination of treatments in terms of process economics and safety would be key towards large scale reclaimed water reuse, especially in low and middle income countries. In addition, combining energy and resource recovery in the treatment chain, might make the system economically self sustainable which would further favor its implementation.
The major challenge in the reuse of wastewater or reclaimed water is its safety. In addition to the well comprehended risks to humans like the presence of pathogenic microorganisms in treated domestic wastewater, several other emerging pollutants like pharmaceutical residues, antibiotic resistance genes, microplastics etc. may a pose threat to humans. The presence of residual nutrients like nitrogen and phosphorous in reclaimed water might make it beneficial for irrigation purposes, however, certain pollutants like pharmaceutical and personal healthcare products and heavy metals may get bio-magnified in the food crops and may render them unfit for long term consumption. Similarly industrial applications might require specific standards. Thus, the choice of tertiary treatment technology would be critical for such applications. This research topic is dedicated to understanding the scientific, technical and policy issues related to wastewater and reclaimed water reuse for various purposes and ways to tackle those issues for maximizing the wastewater “resource” to achieve water circularity. In addition, it would also include papers on energy recovery and nutrient recovery from wastewater for achieving economic circularity.
For this research topic, we welcome Original Research, Reviews, Case Reports, Community Case Studies and Policy Brief articles which highlight
-Issues pertaining to reuse of treated wastewater for various purposes
-Treatment technologies for safe wastewater reuse
-Monitoring emerging pollutants in treated wastewater
-Novel applications of treated wastewater
-Guidelines for safe wastewater reuse for different purposes
-Recovery of nutrients and energy from wastewater

Keywords: Wastewater reuse, Water reclamation, Safe reuse, Water circularity, Economic circularity

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