Fig 6 - uploaded by Satiye Korkmaz
Content may be subject to copyright.
a Water collection system. b Fog harvesting process. c Dew harvesting process. c In the dew harvest, there is no steam flow to the surface (Seo et al. 2016)
Source publication
Fog harvesting is a sustainable, simple and cost-effective technique to collect water from the air. Clean, safe and drinkable water resources are created by installing this fog harvesting apparatus in deserts, in arid regions and in countries with high population density. Here we review principles and recent developments in fog harvesting.
Contexts in source publication
Context 1
... used the surface modification technique based on the chemical oxidation of copper, using their previous work (Schemenauer and Cereceda 1994b;Seo et al. 2016) to modify the properties of tubular surfaces. Figure 6a illustrates the diagram of the water collection system, whereas Fig. 6b, c shows the diagram of fog and dew harvest on the tubular surface built with commercially available Cu tubes. The method is considered to be more advantageous for thermal applications ( Miljkovic et al. 2013;Xiao et al. 2013;Hu et al. 2015;Zhu et al. 2015;Zhao et al. 2015), with easier removal of water droplets from superhydrophobic and oil-infused surfaces. ...
Context 2
... the effects of surface wettability on fog harvesting. Researchers used the surface modification technique based on the chemical oxidation of copper, using their previous work (Schemenauer and Cereceda 1994b;Seo et al. 2016) to modify the properties of tubular surfaces. Figure 6a illustrates the diagram of the water collection system, whereas Fig. 6b, c shows the diagram of fog and dew harvest on the tubular surface built with commercially available Cu tubes. The method is considered to be more advantageous for thermal applications ( Miljkovic et al. 2013;Xiao et al. 2013;Hu et al. 2015;Zhu et al. 2015;Zhao et al. 2015), with easier removal of water droplets from superhydrophobic and ...
Similar publications
The measurement of non-rainfall atmospheric water input (NRWI) in arid environments requires instruments that are capable to detect even smallest amounts of total daily water input of less than 0.1 mm. Microlysimeters yield robust and high precision data of such low NRWI. We provide a technical description of a self-constructed microlysimeter and d...
Citations
... Currently, ~10 to 25% of the world's population suffer from freshwater scarcity crisis as a consequence of steady overpopulation, overconsumption, and climate variations (Kim et al., 2019). Furthermore, 5% of under 5-year-old children living in internationally rural areas have been appraised to die due to contaminated water consumption (Korkmaz & Kariper, 2020). Hence, the catastrophic issue of water shortage has been ranked the 4 th risk leading to global adverse effects (Tang & Guo, 2020). ...
Nanocomposite fabrics have been extensively employed as moisture harvesting media. In this study, flower-like zinc oxide nanostructures were coated on cotton fabrics by precipitation technique at different operational conditions of precursor concentration, temperature, and residence time. Then, the impact of aforementioned parameters on wettability of coated fabrics and morphology of nanostructures were investigated through contact angle measurements and SEM/EDX analyses, respectively. Optimal conditions of the coating process was experimentally determined and later validated by Minitab software. Afterwards, the fabrics prepared at optimal conditions were utilized in moisture harvesting experiments which were planned to scrutinize the effects of 3 parameters; humid airflow rate, temperature, and humidity on the final amount of harvested moisture. Experimental results in terms of water contact angle led to an optimal value of 156°. Moreover, Minitab confirmation of the obtained results revealed that the optimization of coating process occurred at a precursor concentration of 3.1 mM, a temperature of 85°C, and a residence time of 50 minutes. Furthermore, SEM/EDX analyses ascertain the flower-like zinc oxide nanostructure coating as well as its uniform distribution on the fabric surface. The abrasion resistance of the coated nanostructure was evaluated via performing a standard abrasion test proving the coating mechanical stability, as evidenced by a negligible reduction in the contact angle. Finally, optimum moisture harvesting results led to 64.8 mg/cm².h of water, showing the dominancy of air humidity effect on the amount of harvested moisture as compared to factors such as temperature or airflow.
... Although much progress has been made in improving fog collection performance [8,[21][22][23][24], the above research focuses more on the efficient operation of droplet collection systems at high fog flow quantities. However, fog in nature is inevitably variable due to geography, time and climate [25][26][27], and this variation is most evident in fog flow quantity. ...
Fog collection is essential to alleviate water scarcity in arid areas. However, the vast majority of existing fog collectors only work effectively under heavy fog. To broaden fog concentration range for efficient work, an optimization strategy based on wettability combination and fork-row arrangement is proposed systematically in this work. Single-layer experiment results show that hydrophilic (HL) surface with high deposition capacity collects droplets at a faster rate in light fog (25~80 g/h), while the rate of hydrophobic (HB) surface with high drainage capacity is higher in heavy fog (220~500 g/h). Double-layer experiment results show that in light fog, the best combination of double-layer collection electrodes is HL-HL, while HB-HL performs best in heavy fog. A 35% improvement in collection rate can be obtained simply by changing the arrangement from smooth-row(S) to fork-row(F), which is attributed to the increased effective collision area of droplets. In our series of experiments, at 50 g/h, collection rate of double-layer combination HL-HL(F) is 56.7% higher than that of single-layer HL. In particular, collection rate of HB-HL(F) reaches 1434.7 mg/cm2/h at 500 g/h. Such good performance is attributed to the force imbalance of hanging droplets caused by wettability differences, which tends to transport small droplets on HB towards HL directionally, resulting in a rapid droplet slippage. Therefore, the HB-HL accelerates drainage and refreshes capture points. Furthermore, fog collection performance is also influenced by layer spacing, which has an optimal distance. These findings provide a promising method for practical applications of fog collectors in a wide range of fog flow quantities, enhancing adaptability to variable environments.
... Another application for surfaces with patterned contrast in wettability is fog basking, which is used to capture and collect water droplets from mist, which makes it possible to sustain dry areas suffering from a limited supply of drinking water, with an alternative sustainable water source. 60 Some fog basking solutions have been inspired by the fascinating example of some Namib Desert beetle species (some species belonging to geni Stenocara, Onymacris, Physosterna). 61,62 The beetles have patterned elytra with alternating hydrophilic and hydrophobic (waxy) regions. ...
The control of surface wettability is a technological key aspect and usually poses considerable challenges connected to high cost, nanostructure, and durability, especially when aiming at surface patterning with high and extreme wettability contrast. This work shows a simple and scalable approach by using laser-induced graphene (LIG) and a locally inert atmosphere to continuously tune the wettability of a polyimide/LIG surface from hydrophilic to superhydrophobic (Φ ∼ 160°). This is related to the reduced amount of oxygen on the LIG surface, influenced by the local atmosphere. Furthermore, the influence of the roughness pattern of LIG on the wettability is investigated. Both approaches are combined, and the influence of surface chemistry and roughness is discussed. Measurements of the roll-off angle show that LIG scribed in an inert atmosphere with a low roughness has the highest droplet mobility with a roll-off angle of ΦRO = (1.7 ± 0.3)°. The superhydrophobic properties of the samples were maintained for over a year and showed no degradation after multiple uses. Applications of surfaces with extreme wettability contrast in millifluidics and fog basking are demonstrated. Overall, the proposed processing allows for the continuous tuning and patterning of the surface properties of LIG in a very accessible fashion useful for “lab-on-chip” applications.
... The biggest issues with this method are its reliance on high humidity and the mesh's tendency to get clogged [21]. Examples of fog harvesting can be found across the globe with successful implementation in Chile [26], Morocco [27], and elsewhere [28,29]. ...
Atmospheric Water Generators (AWG) extract water from the air using one of three available technologies: refrigeration, sorption, and fog harvesting. In this research, we analyze two refrigeration-based devices and one sorption-based device and their efficacy in providing supplemental water supply across the United States. An AWG can supply potable water to remote and austere locations where clean drinking water might otherwise be unavailable. With increasing water scarcity globally, particularly in historically arid climates, new methods that can draw from an estimated 13,000 km³ in the atmosphere using an AWG becomes important and, potentially, viable. However, due to climatological and technological constraints, not all regions in the world would see the same water production from an AWG as production is driven by high relative humidity and temperature. This climatological reliance also subjects them to dramatic changes in performance depending on the season. By using previously established hydrologic performance indicators (reliability, resilience, and vulnerability) and weather data for the United States, we determine the year-round efficiency metrics of three AWGs. By evaluating three different devices and mapping the efficiency across the United States, this research determines the regional efficacy, as a function of water production, in adopting AWG technology to supplement potable water supply. This study provides important insights into the performance of AWGs with high spatial resolution through comparison of multiple devices. The results indicate minimal viability for a large portion of the United States. However, we highlight the potential for the device to supply water for a remote military installation in Hawaii.
... In addition to the line and dot patterns, researchers have also developed more complicated multimaterial patterns, such as topology mimicking leaf veins [19,20]. Work reported in these and other references, e.g., [21][22][23][24][25][26], demonstrated that multimaterial surfaces with dot and line patterns could enable tunable hydrodynamic properties important or even necessary for a wide range of applications. ...
... A notable water harvesting feature seen in nature is (super)hydrophobicity [52]. By studying the effect of hydrophilic and hydrophobic coatings on wires, Azeem et al. [21] concluded that the latter improved the collection rate of vertical harps. ...
In water-scarce regions where fog is abundant, the population can rely on this resource to obtain fresh water. The potential to harvest fog is confirmed by Large Fog Collector projects worldwide, which are reviewed. Mostly maintenance issues due to environmental and complex social factors compromise the sustainability of such projects. Researchers endeavour to resolve these issues by developing enhanced materials, while others employ biomimetic design, hence creating innovative collectors. The objective of this paper is to survey and review the state-of-the-art and develop a framework of different types of innovative fog collectors, including conceptual, experimental, and operational aspects.
... In this approach, the water generation is achieved through passive means with net-zero energy investment. Fog harvesting and dew harvesting are the two main techniques that have been proposed under this approach (Fessehaye et al., 2014;Korkmaz & Kariper, 2020;Sharan et al., 2017;Tomaszkiewicz et al., 2015). In fog harvesting, water in the form of fog or aerosol droplets are trapped in specially designed structures called fog nets (see Fig. 5). ...
The lack of access to clean water is a growing global challenge that threatens human lives and sustainable development. Many countries are facing their worst-ever water crisis and the situation will be more severe in the coming years owing to many factors including but not limited to growing population, urbanization, unsustainable use of existing water resources, and climate change. Therefore, new technological solutions are required to address the global water crisis on priority. Atmospheric water generation that generates water from the atmospheric humidity is an emerging solution to water scarcity and could be a lifeline to people living in water-stressed and landlocked regions. However, several challenges must be addressed, including energy consumption, cost, operation window, and scalability to ensure the viability and sustainability of atmospheric water generation as a solution for water scarcity. Changes in operating environment conditions have a profound impact on the performance of atmospheric water generation systems, thereby limiting their extensive application. In all climates, an energy-efficient and scalable approach to extract water from the atmosphere is not yet available. The techniques involved in generating water from the atmosphere are still in the nascent stage, providing enormous opportunities to further refine the technology. This article presents a brief introduction to the concept of atmospheric water generation, the underlying principles of various techniques involved and its practical challenges.
... Like other low-impact development concepts, the sponge city model offers a smart and sustainable approach by integrating the power of nature in the urban water cycle, instead of relying solely on engineering systems and gray infrastructure. With its national initiatives already underway, China's sponge city development may offer valuable experiences for cities worldwide who are battling with water shortages and floods in tackling climate change Earth 2021;Fawzy et al. 2020;Korkmaz and Kariper 2020). ...
About one tenth of humans are impacted by water shortages around the globe. Water resilience is worsening under climate change because intensifying weather extremes induce more severe and increasingly frequent droughts and floods. In particular, China, as the world’s most populous nation, has battled with persisting water shortages and devastating floods for decades. As a consequence, Chinese scholars have designed the sponge city concept in the early 2010s to relieve cities from the growing pressure of water shortages and floods. This is done by integrating a more natural, green infrastructure into existing urban drainage pipeline systems for absorbing, storing, and purifying rainwater in a sponge-like manner during rainfall events. Here we review the principles, design guidelines, construction items and assessment requirements of sponge cities and other similar strategies for urban stormwater management. We present four case studies of sponge cities in China in both newly constructed and renovated urban districts. Overall, China's sponge cities appear promising for green urbanization, to relieve cities from water scarcity, devastating floods and urban heat island effects, while restoring the ecological functions and aesthetics of urban natural environments.
... Water plays an important role in human production and life and is the most important resource for humans. [1,2] However, nearly half of the world's population is facing water scarcity. [3][4][5][6] Climate change, increase in population, and water pollution worsen the crisis, with four billion people facing acute water crisis for at least one month of the year. ...
In recent years, the porous sorbent‐assisted atmospheric water harvesting (AWH) method has emerged as an effective approach for solving water crises without geographical restrictions. However, there is a limited array of porous adsorbent materials that can be used for AWH, which are inadequate to meet the needs under different climatic conditions. In light of this, herein, we synthesize a new crystalline porous organic salt (CPOS; denoted as CPOS‐6) possessing a dual hydrogen bond system and verify its applicability toward AWH for the first time. Unlike other reported CPOSs, CPOS‐6 displays an S‐shaped water sorption isotherm owing to the presence of the dual hydrogen bond system. Under simulated drought conditions in Xinjiang Uygur Autonomous Region, CPOS‐6 exhibits long‐term water adsorption‐desorption cycling stability, low water desorption temperature, and ultrarapid adsorption‐desorption kinetics. The results confirm that CPOS‐6 is an effective sorbent material for AWH.
... npj Clean Water (2021)24 Published in partnership with King Fahd University of Petroleum & Minerals ...
This study describes the development of a fog collector material for fog harvesting. Polypropylene (PP) doped with fumed silica (0–2%) was punctured at equal intervals and exposed to fog produced by a humidifier. The amount of water harvested by each sample was measured using an ultrasonic fogger. Polypropylene doped with 1% fumed silica was most effective at harvesting water, and collected almost 19–20 times more water than pure polypropylene. This improvement is due to the surface tension, which decreased from 16.754 mN/m (pure PP) to 13.512 and 9.992 mN/m (0.5% and 1% fumed silica, respectively). On the other hand, when fumed silica doping exceeded 1%, this increased the polymer’s surface tension, measured as 20.6 and 38.1 mN/m for 1.5 and 2% fumed silica doping. We therefore propose fog harvesting using 1% fumed silica-doped polypropylene as a low-cost method for collecting clean water in arid regions.
