Hydrogels: Next Generation Atmospheric Water Harvesting Materials

Alternative new technologies are urgently needed to overcome the rapidly increasing global water scarcity. Atmospheric dew water is a potential source of potable water, as the earth’s atmosphere contains billions of tons of fresh water (98% in a vapor state). The atmospheric water generator (AWG) converts water vapor into liquid water and is a promising solution for water scarcity. We provide the first comprehensive analysis of the chemical profiles of water produced for several months by an AWG in the city of Tel Aviv, Israel. Metals, inorganic ions, volatile organic compounds (VOCs), and semi-VOCs were analyzed in the dew water. The main elements found were ammonium, calcium, sulfate, and nitrate. Location of the sampling site in an urban residential area, between major traffic routes, likely affected the chemical composition of the produced dew water. Nevertheless, the produced water nearly always (day and night in different seasons) met the WHO and Israeli drinking water standards. Thus, even in a highly developed urban environment, the AWG offers an excellent alternative source of safe drinking water throughout the year.

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Ultrahigh solar-driven atmospheric water production enabled by scalable rapid-cycling water harvester with vertically aligned nanocomposite sorbent

Energy & Environmental Science ◽

10.1039/d1ee01723c ◽

2021 ◽

Author(s):

Jiaxing Xu ◽

Tingxian Li ◽

Taisen Yan ◽

Si Wu ◽

Minqiang Wu ◽

...

Keyword(s):

Fresh Water ◽

Water Scarcity ◽

Human Society ◽

Clean Water ◽

Water Harvesting ◽

Rapid Cycling ◽

Water Production ◽

Atmospheric Water ◽

Significant Challenge ◽

Vertically Aligned

Fresh water scarcity is a globally significant challenge threatening the development of human society. Sorption-based atmospheric water harvesting offers an appealing way to solve this challenge by extracting clean water...

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Downsizing our Water Footprint

elni Review ◽

10.46850/elni.2012.011 ◽

2012 ◽

pp. 63-67

Author(s):

Marga Robesin

Keyword(s):

Drinking Water ◽

Water Use ◽

Water Scarcity ◽

Water Footprint ◽

World Population ◽

Water Infrastructure ◽

The World ◽

Clean Drinking Water ◽

Near Future ◽

Sanitary Services

884 million people are without adequate access to clean drinking water and 2.6 billion people lack access to basic sanitary services. Due to preventable water and sanitation-related diseases an average of 5.000 children dies each day. This is not only caused by the absence of local adequate water infrastructure, but also by regional water scarcity. In the near future the problem of water scarcity will even increase in several regions of the world because of factors like a growing world population and climate change. How can we stop this fatal trend? Left aside the need for a better water infrastructure and other measures to improve access to clean drinking water and sanitary services, the global water demand needs to be reduced. Not only for the sake of people, but also for the protection of ecosystems and biodiversity. Using water saving showerheads in our households is not enough to achieve substantial water use reduction. In the past decade scientists have developed methods to calculate our water footprint in the world. In 2011 the Global Standard for Water Footprint Assessment, developed by the Water Footprint Network (WFN) was published. It shows that the major part of our water footprint (WF) consists of water that is used for the production of our food and other products we consume. Famous examples are the 15.000 litres water needed to produce one kg beef or the fact that 140 litres water are used for the production of one (Dutch) cup of coffee. Reduction of humanity's water footprint is urgently needed in order to keep water use within the boundaries of our planet. This article intends to give a short overview of current discussions on the question how to achieve substantial water footprint reduction, focussing in particular on certification and labelling.

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Global potential for harvesting drinking water from air using solar energy

Nature ◽

10.1038/s41586-021-03900-w ◽

2021 ◽

Vol 598 (7882) ◽

pp. 611-617

Author(s):

Jackson Lord ◽

Ashley Thomas ◽

Neil Treat ◽

Matthew Forkin ◽

Robert Bain ◽

...

Keyword(s):

Drinking Water ◽

Technological Development ◽

Google Earth ◽

Water Harvesting ◽

Atmospheric Water ◽

Tropical Regions ◽

Global Challenge ◽

Trade Offs ◽

Sorbent Materials ◽

The Impact

AbstractAccess to safely managed drinking water (SMDW) remains a global challenge, and affects 2.2 billion people1,2. Solar-driven atmospheric water harvesting (AWH) devices with continuous cycling may accelerate progress by enabling decentralized extraction of water from air3–6, but low specific yields (SY) and low daytime relative humidity (RH) have raised questions about their performance (in litres of water output per day)7–11. However, to our knowledge, no analysis has mapped the global potential of AWH12 despite favourable conditions in tropical regions, where two-thirds of people without SMDW live2. Here we show that AWH could provide SMDW for a billion people. Our assessment—using Google Earth Engine13—introduces a hypothetical 1-metre-square device with a SY profile of 0.2 to 2.5 litres per kilowatt-hour (0.1 to 1.25 litres per kilowatt-hour for a 2-metre-square device) at 30% to 90% RH, respectively. Such a device could meet a target average daily drinking water requirement of 5 litres per day per person14. We plot the impact potential of existing devices and new sorbent classes, which suggests that these targets could be met with continued technological development, and well within thermodynamic limits. Indeed, these performance targets have been achieved experimentally in demonstrations of sorbent materials15–17. Our tools can inform design trade-offs for atmospheric water harvesting devices that maximize global impact, alongside ongoing efforts to meet Sustainable Development Goals (SDGs) with existing technologies.

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Ensuring access to water in an emergency context: Towards an overexploitation and contamination of water resources?

Social & Legal Studies ◽

10.1177/09646639211031626 ◽

2021 ◽

pp. 096466392110316

Author(s):

Chloé Nicolas-Artero

Keyword(s):

Drinking Water ◽

Water Resources ◽

Qualitative Methods ◽

Water Scarcity ◽

Water Rights ◽

Environmental Crisis ◽

Supply Network ◽

Mining Pollution ◽

Access To Water

This article shows how geo-legal devices created to deal with environmental crisis situations make access to drinking water precarious and contribute to the overexploitation and contamination of water resources. It relies on qualitative methods (interviews, observations, archive work) to identify and analyse two geo-legal devices applied in the case study of the Elqui Valley in Chile. The first device, generated by the Declaration of Water Scarcity, allows private sanitation companies to concentrate water rights and extend their supply network, thus producing an overexploitation of water resources. In the context of mining pollution, the second device is structured around the implementation of the Rural Drinking Water Programme and the distribution of water by tankers, which has made access to drinking water more precarious for the population and does nothing to prevent pollution.

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Diarrhea prevalence in a randomized, controlled prospective trial of point-of-use water filters in homes and schools in the Dominican Republic

Tropical Medicine and Health ◽

10.1186/s41182-020-00291-y ◽

2021 ◽

Vol 49 (1) ◽

Author(s):

Nathan Tintle ◽

Kristin Van De Griend ◽

Rachel Ulrich ◽

Randall D. Wade ◽

Tena M. Baar ◽

...

Keyword(s):

Drinking Water ◽

Water Samples ◽

Controlled Trial ◽

World Health ◽

Dissolved Metals ◽

Randomized Controlled ◽

Point Of Use ◽

Diarrhea Prevalence ◽

Clean Drinking Water ◽

Post Filter

Abstract Background Lack of sustainable access to clean drinking water continues to be an issue of paramount global importance, leading to millions of preventable deaths annually. Best practices for providing sustainable access to clean drinking water, however, remain unclear. Widespread installation of low-cost, in-home, point of use water filtration systems is a promising strategy. Methods We conducted a prospective, randomized, controlled trial whereby 16 villages were selected and randomly assigned to one of four treatment arms based on the installation location of Sawyer® PointONE™ filters (filter in both home and school; filter in home only; filter in school only; control group). Water samples and self-reported information on diarrhea were collected at multiple times throughout the study. Results Self-reported household prevalence of diarrhea decreased from 25.6 to 9.76% from installation to follow-up (at least 7 days, and up to 200 days post-filter installation). These declines were also observed in diarrhea with economic or educational consequences (diarrhea which led to medical treatment and/or missing school or work) with baseline prevalence of 9.64% declining to 1.57%. Decreases in diarrhea prevalence were observed across age groups. There was no evidence of a loss of efficacy of filters up to 200 days post-filter installation. Installation of filters in schools was not associated with decreases in diarrhea prevalence in school-aged children or family members. Unfiltered water samples both at schools and homes contained potential waterborne bacterial pathogens, dissolved heavy metals and metals associated with particulates. All dissolved metals were detected at levels below World Health Organization action guidelines. Conclusions This controlled trial provides strong evidence of the effectiveness of point-of-use, hollow fiber membrane filters at reducing diarrhea from bacterial sources up to 200 days post-installation when installed in homes. No statistically significant reduction in diarrhea was found when filters were installed in schools. Further research is needed in order to explore filter efficacy and utilization after 200 days post-installation. Trial registration ClinicalTrials.gov, NCT03972618. Registered 3 June 2019—retrospectively registered.

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Janus Membrane with Novel Directional Water Transport Capacity for Efficient Atmospheric Water Capture

Nanoscale ◽

10.1039/d1nr01120k ◽

2021 ◽

Author(s):

Jing Wu ◽

Baona Ren ◽

Haohong Pi ◽

Xin Zhao ◽

Miaomiao Hu ◽

...

Keyword(s):

Fresh Water ◽

Water Transport ◽

Water Scarcity ◽

Low Cost ◽

Transport Capacity ◽

Atmospheric Water ◽

Human Survival ◽

Survival And Development ◽

Energy Independence

Fresh water scarcity becomes a crisis to human survival and development. Atmospheric water capture with remarkable advantages such as energy-independence, low-cost, etc., has been supposed as a promising way to...

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