Our selection of open access publications on water reuse – January 2024
Our selection this quarter includes open-access articles published in Water Science and Technology, IWA Publishing, and Elsevier, on promoting municipal water reuse without a scarcity driver, understanding the performance of lagoon and constructed wetland systems for tertiary wastewater treatment, learning about a nature-based tertiary wastewater treatment technology, a new evaluation framework for the assessment of wastewater heat recovery potential coupled with wastewater reuse and more…Enjoy reading!
Municipal Water Reuse
Title: Making waves: Promoting municipal water reuse without a prevailing scarcity driver
Authors: Duckett D., Troldborg M., Hendry S. and Cousin H.
In: Water Research
Abstract: The wealth of water reuse research in scarcity and/or rapid urbanisation contexts has underpinned significant change in many relatively water scarce contexts. Less progress has been achieved in water rich contexts; a fact illustrated by the lack of change on the ground. The Climate Emergency demands that all municipalities urgently contribute to more efficient resource management of water. Consequently, to advance municipal scale reuse projects in locations where scarcity is not forcing the issue, for example Scotland, there is a need to predicate water reuse on different drivers, specifically climate change and the circular economy. Moreover, greater contextual sensitivity needs to be applied when exploring barriers to reuse to more critically exploit opportunities, for example avenues to reform complex regulatory frameworks, different contingencies around trust, and different potential degrees of the yuck factor. To achieve this, new initiatives need to be urgently undertaken to consider the barriers to reuse that will not be swept aside by the imperative of scarcity. The notion of a yum factor, whereby positive sentiments are nurtured to combat instinctive repugnance, coined as yuck by the bioethicist Arthur Caplan, is advanced as a strategic objective to promote more rapid expansion of municipal scale reuse.
Agricultural Water Reuse
Title: Performance of lagoon and constructed wetland systems for tertiary wastewater treatment and potential of reclaimed water in agricultural irrigation
Authors: Mancuso G., Lavrnić S., Canet-Martí A., Zaheer A., Avolio F., Langergraber G., and Toscano A.
In: Journal of Environmental Management
Abstract: Climate change poses challenges to agricultural water resources, both in terms of quantity and quality. As an adaptation measure, the new European Regulation (EU) 2020/741 establishes different water quality classes for the use of reclaimed water in agricultural irrigation. Italy is also working on the definition of a new regulation on reclaimed water reuse for agricultural irrigation (in substitution of the current one) that will also include the specific requirements imposed by the European one. Nature-based Solutions (NBS) can be a cost-effective and environmentally friendly way to facilitate water reclamation and reuse. The present study reports the outcomes of a long-term monitoring campaign of two NBS (e.g., a constructed wetland (CW) and a lagoon system (LS)) comparing influent and effluent concentrations of different contaminants (e.g., E. coli, BOD5, TSS, TN and TP) with the threshold values imposed by the new regulations. The results showed that in both the case studies, E. coli (about 100 CFU 100 mL−1) and BOD5 (lower than 25 mg L−1) mean effluent concentration need to be further reduced in reclaimed water to be suitable for unlimited reuse. As a negative aspect, in both the monitored NBS, an increase in TSS mean concentration in the effluent was observed, up to 40 mg L−1 in the case of the LS, making reclaimed water unsuitable for agricultural reuse. The CW has proven to be more effective in nitrogen removal (the effluent mean concentration was 3.4 mg L−1), whereas the LS was better at phosphorus removal (with an effluent mean concentration of 0.4 mg L−1). Based on the results, recommendations were made to further improve the performance of both systems in order to have adequate water quality, even for class A. Furthermore, the capacity of reclaimed water to meet crop water and nutrient needs was analyzed, and total nitrogen removal rate coefficients were calculated for the design of future LSs.
Public Perception in Water Reuse
Title: Key perceptions associated with attitudes towards water reuse in a Swedish town
Authors: Gullberg Y., Samuelsson K., Anders Brandt S.
In: Water Reuse
Publisher: IWA Publishing
Abstract: As climate change and urbanization affect current water management systems, new solutions and approaches rooted in public acceptance are needed to ensure future water supply. In this study, we examine public attitudes to reuse of recycled water and associated worldviews, values, and perceptions in a site without historical water issues. A survey of 143 randomly sampled residents in the municipality of the growing Swedish town Knivsta revealed that 81.4% of the respondents had a positive attitude towards using recycled water in general. The results did not indicate any differences in attitudes between those living in and outside the municipality’s urban areas. Perceived benefits and risks were found to be significantly related to both attitudes towards using recycled water in general and to the extreme case of using it for drinking purposes. Additionally, trust in public authorities was highly predictive of attitudes towards drinking recycled water. Furthermore, attitudes were found to be related to an environmental worldview and underlying biospheric, altruistic, and hedonic values. This indicates a need to consider the intended purpose as well as engaging with underlying values as part of the technology legitimation process for improving the chances of successful implementation of water recycling technologies.
Nature-based Solutions for Water Reuse
Title: Harnessing water fleas for water reclamation: A nature-based tertiary wastewater treatment technology
Authors: Abdullahi M., Stead I., Bennett S., Orozco R., Abdallah M.A.-E., Jabbari S., Macaskie L.E., Tzella A., Krause S., Al-Duri B., Lee R.G., Herbert B., Thompson P., Schalkwyk M., Getahun S., Dearn K.D. and Orsini L.
In: Science of the Total Environment
Publisher: Elsevier B.V.
Abstract: Urbanisation, population growth, and climate change have put unprecedented pressure on water resources, leading to a global water crisis and the need for water reuse. However, water reuse is unsafe unless persistent chemical pollutants are removed from reclaimed water. State-of-the-art technologies for the reduction of persistent chemical pollutants in wastewater typically impose high operational and energy costs and potentially generate toxic by-products (e.g., bromate from ozonation). Nature-base solutions are preferred to these technologies for their lower environmental impact. However, so far, bio-based tertiary wastewater treatments have been inefficient for industrial-scale applications. Moreover, they often demand significant financial investment and large infrastructure, undermining sustainability objectives. Here, we present a scalable, low-cost, low-carbon, and retrofittable nature-inspired solution to remove persistent chemical pollutants (pharmaceutical, pesticides and industrial chemicals). We showed Daphnia’s removal efficiency of individual chemicals and chemicals from wastewater at laboratory scale ranging between 50 % for PFOS and 90 % for diclofenac. We validated the removal efficiency of diclofenac at prototype scale, showing sustained performance over four weeks in outdoor seminatural conditions. A techno-commercial analysis on the Daphnia-based technology suggested several technical, commercial and sustainability advantages over established and emerging treatments at comparable removal efficiency, benchmarked on available data on individual chemicals. Further testing of the technology is underway in open flow environments holding real wastewater. The technology has the potential to improve the quality of wastewater effluent, meeting requirements to produce water appropriate for reuse in irrigation, industrial application, and household use. By preventing persistent chemicals from entering waterways, this technology has the potential to maximise the shift to clean growth, enabling water reuse, reducing resource depletion and preventing environmental pollution.
Water and Energy Recovery
Title: A new evaluation framework for the assessment of wastewater heat recovery potential coupled with wastewater reuse
Authors: Ramadhan, E. and Oh, J.
In: Water Science and Technology
Publisher: IWA Publishing
Abstract: The integration of wastewater heat recovery (WWHR) and wastewater reuse offers a numerous advantage, making its application possible in various sectors. Nevertheless, this concept faced challenges to the identification of appropriate location. Existing research lacks comprehensive evaluation methods that encompass a various factor for effective decision-making. This study introduces a new evaluation framework that involves different aspects, including thermal energy potential and spatial distribution analysis. The novelty of this research lies in its unique focus on the combination of WWHR and wastewater reuse. Moreover, it introduces a structured evaluation framework that considers multiple criteria and expert opinions, enhancing decision-making precision. Multi-criteria decision analysis (MCDA) was applied to select assessment criteria, which were categorized into three aspects: water–energy supplier, water–energy consumers, and water–energy station. The relative importance of criteria was determined using the analytical hierarchical process (AHP). The results of the AHP highlight significance of factors: treated wastewater flow rate; treated wastewater temperature; water–energy supply distance, and type of water–energy consumer. These factors were assigned weight values of 0.297, 0.186, 0.123, and 0.096, respectively. It is emphasizing their influence in the decision-making process that potential locations depend on the water–energy supplier and water–energy consumer as supply and demand sources.