{"id":354,"date":"2020-02-20T13:47:24","date_gmt":"2020-02-20T13:47:24","guid":{"rendered":"http:\/\/blogs.dickinson.edu\/writingsciencenews2020\/?p=354"},"modified":"2020-02-20T13:47:24","modified_gmt":"2020-02-20T13:47:24","slug":"drinking-water-from-salt-water-a-new-approach-to-desalination","status":"publish","type":"post","link":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/2020\/02\/20\/drinking-water-from-salt-water-a-new-approach-to-desalination\/","title":{"rendered":"Drinking Water from Salt Water: A New Approach to Desalination"},"content":{"rendered":"

Desalination, the process of removing salt from water, is a practical way to provide drinking and irrigation water to communities who have lost their primary water source.\u00a0 More commonly, it acts as a backup in case the inevitable should occur and is slowly being implemented into more communities, particularly along coastlines.\u00a0\u00a0<\/span><\/p>\n

A team of researchers from the University of Bath has devised a low cost and low maintenance method to desalinate water in potentially bulk quantities.\u00a0 The method consists of three primary components: ionic rectifiers (positive and negatively charged filters), ionic diodes (positive and negatively charged sources of electricity), and 3-D printed water basins.\u00a0<\/span><\/p>\n

This new technique can not only separate salt from water, but also compile the salt to be collected.<\/span><\/p><\/blockquote>\n

The ionic diodes work with the ionic resistors to form am electrically driven circuit.\u00a0 The researchers flip a switch to shift the charge of the voltage in the saltwater from positive to negative and back again.\u00a0 This blocks and opens varying chambers, resulting in a build-up of salt in outside chambers, while the desalinated water remains inside the circuit.\u00a0 In short, one chamber holds the salt-free water while another collects the extracted salt.<\/span><\/p>\n

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Model and picture of the desalination machine.<\/p><\/div>\n

The concentration of salt in the inside of the circuit, where the desalinated water is contained, is closely measured along with the intensity of electricity.\u00a0 <\/span>As the amount of salt in the center decreased, so did the ionic currents. If everything goes smoothly, an ideal rectification ratio of 4-5 would ensure optimization of energy\/electricity use in the conversion process.<\/span><\/p>\n

Unfortunately for the research team, this was not the case.\u00a0 Instead, they recorded an abysmal ratio of two and lower! The thin film used to strain the saltwater and help conduct the positive and negative charges was determined to be the main cause of energy loss.<\/span><\/p>\n

The film, named Fumasep FAS-130, was the thinnest material available to the team that would still (technically) work, but it rapidly degrades when attached to an activated circuit.\u00a0 When all was said and done, their brilliant idea to separate salt from the water and to collect the salt with little hands-on work, resulted in a flimsy 12% efficiency rate.<\/span><\/p>\n

\"water

Pink salt in water. Picture courtesy of Creative Commons.<\/p><\/div>\n

Fortunately, the team is confident their low efficiency is an easy fix.\u00a0 First and foremost, they\u2019ll need a better film, preferably one that doesn\u2019t degrade immediately upon being placed in saltwater.\u00a0 Altering the size and location of the holes in the film used to filter the water could also yield improvements. In addition, stronger electrodes (therefore stronger electrical voltage) and larger vats of saltwater could result in creating drinking water in bulk through this process.<\/span><\/p>\n

So yes, this technique certainly has its issues, but it offers insight into a new method of desalination with incredible potential.\u00a0 It doesn\u2019t have any moving parts, only electricity from the diodes, so it needs little to no maintenance, it\u2019s cheap compared to other methods, and (when the efficiency issue is sorted out) will be low energy as well.\u00a0 This simple process could one day save countless communities struggling from lack of water after natural disasters, all by removing salt from water.<\/span><\/p>\n

\n

https:\/\/www.sciencedirect.com\/science\/article\/pii\/S0011916419321940?via%3Dihub<\/a><\/p>\n

Putra, B. R.; Madrid, E.; Tshwenya, L.; Arotiba, O. A.; Marken, F.;\u00a0 An AC-driven desalination\/salination system based on Nafion cationic rectifier<\/em>.\u00a0 Science Direct 2020.\u00a0 DOI: https:\/\/doi.org\/10.1016\/j.desal.2020.114351<\/p>\n","protected":false},"excerpt":{"rendered":"

Desalination, the process of removing salt from water, is a practical way to provide drinking and irrigation water to communities who have lost their primary water source.\u00a0 More…<\/p>\n","protected":false},"author":4279,"featured_media":356,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2545],"tags":[19698],"class_list":["post-354","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-environment","tag-chemistry"],"_links":{"self":[{"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/posts\/354","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/users\/4279"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/comments?post=354"}],"version-history":[{"count":0,"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/posts\/354\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/media\/356"}],"wp:attachment":[{"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/media?parent=354"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/categories?post=354"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.dickinson.edu\/writingsciencenews2020\/wp-json\/wp\/v2\/tags?post=354"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}