Posted on 08/31/2019 11:50:48 PM PDT by 2ndDivisionVet
Over 2 billion people are facing a water crisis, and water-related hygiene and sanitation problems. Clean water is the base for economic development of any society. Water treatment produces clean water. Water treatment includes sedimentation, filtration, aeration, solar treatment, chlorination, and sterilization by boiling. A wide range of treatment processes have evolved to suit the different local conditions. Water treatment must produce clean water, which is having all contaminants safely below the maximum permissible limits (MPL). With oft revised MPL, new materials are explored to address the presence of contaminants such as microbes, heavy metal ions, oils, pesticides, disinfection byproduct precursors, and innumerable chemicals.
Carbon has been in use for water treatments with evidence found dating back to the Harappan civilization. The latest technologies involve ultrafiltration (UF), reverse osmosis (RO), and desalination methods. Carbon is also an essential component in all the water treatments available today in the form of graphene.
With graphene, a single atomic layer of carbon, a clean water solution has emerged. Cutting edge water filtration systems are developed using graphene to remove highly hazardous contaminants that are otherwise not efficiently removed by previous technologies. The properties that make graphene unique to water treatments are large surface area, little or no cytotoxicity, large delocalized ∏-electrons and tunable chemical properties. Importantly, graphene can be easily reused for the purpose with minimal chemical alterations.
(Excerpt) Read more at azocleantech.com ...
I wonder how much it will lower the costs of desalination?
From what I understand, Israel has it down to 50 cents for 1,000 litres.
Carbon has been in use for water treatments with evidence found dating back to the Harappan civilization. The latest technologies involve ultrafiltration (UF), reverse osmosis (RO), and desalination methods. Carbon is also an essential component in all the water treatments available today in the form of graphene.
Just a flippin minute here! Carbon is a pollutant. Is someone trying to have it both ways, or is reality finally coming back into favor?
50 years ago when I was in Vietnam, I was impressed by the fact that they used 2 water systems. Potable water for drinking and cooking and filtered only water for everything else. It’s just too expensive to use drinking water for everything. Gotta admit though, it took a while to get used to an extra spigot on the sink (hot, cold & potable).
We have a door knocking, water product/testing company in the area that is discovering radon gas, in several neighbors’ well water samples. They just happen to have a whole house carbon filter system that they sell, that fixes it...
Biggles’s Chewing gum NOW WITH GRAPHENE !!!!
Latest buzzword - not really a solution for everything (we have heard lots of claims over the last century for so many whizzbang things that didnt pan out ...)
Needs more information that the graphene (electrical properties, large surface area property, structural property ? ) How this will *IMPROVE* water filtration systems ?
Old activated charcoal filters opened binding points on the carbon atoms (and had tiny granules for max surface area). Graphene is a 2 dimensional carbon matrix - if you start ‘activating’ it you destroy its structure. So it sounds like it is some other mechanism to be employed for its filtration effect - electrostatic attraction ?? (charged surface perhaps like in many fancy air filters) - which though only works on certain types of pollutants.
SO another incremental advancement which probably will require other process improvements (like mass graphene production) to make it viable for mass use.
Mass production of graphene - not so good yet - water filters will use alot
Electrolysis of water is another approach though uses much more energy. Disassemble the water into oxygen and hydrogen gasses, filter those separately, then reassemble the atoms back into ultra pure water on the other side. This process wouldn’t filter out the microbes but disassemble them, extracting their water for reuse as well.
Callaway has come out with golf balls with graphene in them. Too expensive for me but an extra ten or so yards off the tee would be helpful.
It ain't there yet.
Thank you for this. I posted on this back about 5 years ago on social media, commenting then that if we could get the tech right, it would make the greatest progress for humanity since discovery that sterilization of instruments halts disease.
Potable water could be the greatest blessing for huge swathes of population in third world countries that one could imagine.
I am very excited about graphene for desalination.
Thank you again for posting this.
Used to make trickling filters and we got 90% BOD removal with recirculatign. It was low energy effective treatment and perfect for the developing world where essentially no sewage is even collected let alone treated. High tech things like reverse osmosis are for the highly developed societies who can maintain them.
Where clean water is needed, they need stable governments that cam do simple things first. The technology is already here.
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Interesting: 10 Uses for Graphene.
Carbon is not a pollutant. Activated charcoal (carbon) is commonly used in all kinds of filtration, making water safe. Saying carbon is a pollutant is the same as saying water is deadly because people drown in it.
Has to be an enzyme catalyst.
Not peeing and pooing in it should be #1.
Many labs have come up with novel ideas for mass graphene production. I’ve posted some of them here in the past.
Didn't check, probably a dead link, "Skeptical Environmentalist", I'm sure this is a reprise, but I hadn't pulled this one out in a while.chapter 1, "Things are getting better"When the water supply and sanitation services were improved in cities throughout the developed world in the nineteenth century, health and life expectancy improved dramatically. Likewise, the broadening of education from the early nineteenth century till today's universal school enrolment has brought literacy and democratic competence to the developed world. These trends have been replicated in the developing world in the twentieth century. Whereas 75 percent of the young people in the developing world born around 1915 were illiterate, this is true for only 16 percent of today's youth. And while only 30 percent of the people in the developing world had access to clean drinking water in 1970, today about 80 percent have... There are still more than a billion people in the Third World who do not have access to clean drinking water.
by Bjorn Lomborg
[pdf]
My point precisely. I chose not to use /s because the notion carbon is a pollutant is so far off the reality scale that only democrats find it believable. How does one imagine sequestration of plant food for example? Much less actually doing it. Evidence be damned.
Technically graphene is three dimensional. It is only one atom thick, but that thickness makes it 3 dimensional. Current production methods do not produce economical large area graphene.
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