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Desalination Breakthrough Could Lead to Cheaper Water Filtration
- tripsus 6y agoThank you for sharing this.
- twic 6y agoThis is the actual paper, which is not open access: https://science.sciencemag.org/content/371/6524/72 https://science.sciencemag.org/content/371/6524/72
- dstick 6y agoI always wondered, so now’s the time to ask I guess, why aren’t these publicly accessible? Aren’t they paid for with government (i.e. public) money?
- jcranmer 6y agoNot necessarily. I don't have access to the actual article itself, so I can't read the section of the article that indicates who funded the work. But several authors do list corporate affiliation (DuPont and Dow), not that that is itself proof of non-public funding.
- the_svd_doctor 6y agoEven when you get a government grant for research, sometimes there are open-access requirements for publications, but sometimes not. It varies. Paper directly written by government employees (like national labs) are usually accessible for free (like on https://www.osti.gov/ https://www.osti.gov/).
- ortusdux 6y agoWould it be possible to DPR these publications? I would assume that the funding agency retains a copy of the paper once published.
- swebs 6y ago>Paper directly written by government employees (like national labs) are usually accessible for free I'm pretty sure all of them are required to be in public domain
- Finnucane 6y agoSome legislation has been proposed in the US Congress to require access to research paid for with tax money (seems pretty reasonable), but so far I don't think it's been able to get past Dr. No.
- driverdan 6y agoRead the article. It says it was funded by DuPont.
- dstick 6y agoThat doesn’t answer my question without prior knowledge. Luckily others did manage to provide an insightful answer. > why aren’t these publicly accessible? And you say: it’s sponsored by Dupont. So let me rephrase the question incorporating the new bit of information you provided: Why would a paper be hidden behind a paywall if it’s sponsored by a commercial company? It would make sense if it was completely off limits. But paying a few hundred dollars (?) means it is still semi public. It’s no secret, but it’s not public either. Why?
- tetris11 6y agoTo prop up the journal, both financially and from an exclusivity angle. If the editors of the journal happen to be friends of DuPont, and the research is of actually that impactful, than a barrier to access might be beneificial
- jeroenhd 6y agoIt's only partially supported by public money, as far as I can tell. Perhaps the industrial sponsors don't want it to be open access? Luckily, the paper is accessible through SciHub it seems. From the paper: Funding: Financial support from The Dow Chemical Company and DuPont is acknowledged. T.E.C. and E.D.G. acknowledge financial support from the National Science Foundation under awards DMR-1609417 and DMR-1905550. K.P.B., A.L.Z., and E.D.G. also acknowledge support from the Center for Membrane Science, Engineering, and Technology (MAST) and the National Science Foundation under award IIP-1841474. M.K. acknowledges support from the National Science Foundation under award CBET-1946392. B.G. and B.K. are funded in part by the National Science Foundation under award CMMI-1906194. B.G. and B.K. also acknowledge computing support from XSEDE TG-CTS110007
- bee_rider 6y agoThe government probably doesn't care enough to bother setting up some sort of repository of papers. Also, there are some pretty prestigious journals out there. I'm sure there are academics who'd want a whole lot more money if the government asked them to stop publishing in the journals that their peers read.
- AnHonestComment 6y agoI’m not following the logic in your last paragraph. If every researcher who took public funds (even by proxy, from the university) was required to publish in an open access journal... it seems like enough research would shift that either prestigious journals would become open access or existing open access journals would become prestigious.
- asdff 6y agoI believe all publicly funded research is open access after a year. NIH at least.
- Faaak 6y agoAnd for those wondering, you should not go to sci-hub to get the paper, because that would be illegal ;-).
- trickstra 6y agoAccording to the new copyright law in Japan, you could actually be criminally prosecuted for downloading papers from scihub even if you never share them. Starting today.
- xvilka 6y agoBad news for Japanese science, good for their neighbor rivals I suppose. Shooting themselves in their own feet.
- hanniabu 6y agoWill we ever see this technology any time soon or is this like battery tech?
- maxerickson 6y agoLithium ion batteries went through an incredible revolution the last 10 years, prices dropped by a factor of ~10. https://twitter.com/ProfRayWills/status/1342632562477264896 https://twitter.com/ProfRayWills/status/1342632562477264896
- eloff 6y agoThat's ironically why we don't see new battery tech materialize. It has to come out of the gate more cost efficient than Li Ion, which is a tall order now with all the efficiencies of scale the latter enjoys. I believe the term technological lock in is used to describe this problem.
- choeger 6y agoThat's not entirely true. The technique to mass-produce Li ion cells (basically: create massive sandwiches and roll them) can probably be applied to most other chemistries.
- eloff 6y agoI think that's mostly only superficially similar, but I'm not an expert in the field.
- bluGill 6y agoChemically it is hard to believe that we can do better than lithium anyway.
- eloff 6y agoI don't know about that, but we could definitely do cheaper though.
- VBprogrammer 6y agoI'm sure there are answers in the actual paper behind this press release but I wonder how much more it costs to make the membrane so much more uniform.
- cinntaile 6y agoPapers don't usually talk about cost, so I wouldn't count on it.
- MichaelZuo 6y ago“Desalination Breakthrough Could Lead to Cheaper Water Filtration if we don’t consider costs” sounds like a more honest title
- cjbenedikt 6y agoThere will still be a brine problem though...https://unu.edu/media-relations/releases/un-warns-of-rising-levels-of-toxic-brine.html#:~:text=Explore-,UN%20Warns%20of%20Rising%20Levels%20of%20Toxic%20Brine,Plants%20Meet%20Growing%20Water%20Needs&text=Globally%2C%20plants%20now%20discharge%20142,(1%20foot)%20of%20brine https://unu.edu/media-relations/releases/un-warns-of-rising-....
- hinkley 6y agoAs I understand, there are partial solutions to this. Using some of the brine, for one, and combining the brine with treated wastewater for another. The latter depends a lot on how closed cycle your process is. Most of the water I use to shower or wash my clothes ends up in the sewer. Filling a swimming pool, not so much. Watering my lawn, only what overflows into the storm water system. It's also distinctly possible we may have to build offshore desal plants to keep the thermohaline cycle running, using the brine as geoengineering.
- legulere 6y ago> Greg Foss of the Texas Advanced Computing Center helped visualize these simulations Where are those visualizations?
- dirtyid 6y agoFeels like cheap desalination breakthrough every year. I know some middle east petro-states are building out the infrastructure, but it doesn't seem like there's broad adoption. Is it because cheap is still not cheap enough? Granted I don't follow developments closely. I just want better non flush/composting toilets.
- oxfordmale 6y agoI had an uncle who worked in the Middle East. One of the major problems with desalination plants is corrosion of all the pipe work, due to the high salt content. Better membranes will make a difference, but will not solve the corrosion issue that reduces the life time of a desalination plant.
- achow 6y agoAren't plastics or polymer inert to salt water?
- InvaderFizz 6y agoYes, but I would guess that at the volumes these pipes will be pushing, the abrasive qualities of a high salt concentrate makes such soft piping material susceptible to being eaten through rather quickly.
- ianai 6y agoSo use lower volume across more pipes in parallel? Seems like something to engineer around.
- sudosysgen 6y agoSeems like something where ceramic-like coatings would help.
- CyberDildonics 6y agoWhat about cross linked polyethylene (PEX) ? Why use metal pipes at all?
- rconti 6y ago> The seeds were planted when DuPont researchers found that thicker membranes were actually proving to be more permeable. This came as a surprise because the conventional knowledge was that thickness reduces how much water could flow through the membranes. It's amazing how often "how it works" is taken for granted. This reminds me of the trend of racing bicycle tires. It used to be "obvious" that you wanted to run a skinny narrow tire at high pressure, for better aerodynamic and rolling efficiency. Even when they started wind tunnel (for tires and wheels) and rolling resistance testing, it was done on steel rollers, not on actual road surfaces. It was assumed that rough roads caused efficiency losses primarily in tire flex (heat), so it made sense to keep pressures high. In the past decade or so, there's been a radical shift towards wider tires and wheels. There are a lot of people riding/racing on 28-32mm wide tires where you would have been laughed at a decade ago, and told to go back to the "efficient" 23mm wide tires. 10-15 years ago, you'd want to be running 120psi on a 23mm wide tire and today you want to run your tire pressure as LOW as possible, and run a wider tire to compensate, to give more air volume to spread the load and bumps across. The rolling resistance is LOWER, because they've found that the energy losses from rough roads or from bumps is in the tremendous amount of energy expended to move the 150-200lbs of "unsuspended" rider and bicycle up and down rapidly. You're losing single-digit watts in rolling resistance on that lower pressure tire, but saving tens or hundreds of watts in energy that would be lost moving the rider's mass up and down. I'm not kidding about the "laughed at" part, either. I'm looking up how wide a tire I can fit on my 12 year old road bike, and there are plenty of downright ABUSIVE forum posts from just 6 or 8 years ago, telling people to go buy a mountain bike if they want to run wider than 25mm tires on my particular bicycle, where I'm trying to fit a 28 and would really like to run a 32 if possible. And a lot of these findings started off as "huh, that's weird" when testing newer wheel shapes in the real world. https://cyclingtips.com/2016/08/cyclingtips-podcast-episode-9-rethinking-road-bike-tire-sizes-and-pressures/ https://cyclingtips.com/2016/08/cyclingtips-podcast-episode-...
- baxtr 6y ago> there are plenty of downright ABUSIVE forum posts from just 6 or 8 years ago Reminds me of another post from today: https://news.ycombinator.com/item?id=25600274 https://news.ycombinator.com/item?id=25600274
- thomas 6y agoI've often wondered if home water filters, which can filter out lots of things [0] were doing light desalination. A slight amount of salt in water is desirable in specialty water like Vichy, but I'd imagine it would be unhealthy all the time. 0 https://helpatmyhome.com/aquasana-aq-5300-water-filter-review/ https://helpatmyhome.com/aquasana-aq-5300-water-filter-revie... filter with the most ANSI/NSF certs that I've seen
- shakezula 6y agoDesalination is a good tech to put some research into now as opposed to when climate change happens too quickly for us to adapt. Another poster pointed out it’s not popular because it’s not needed right now, which I agree with, but it will probably be a tech our race relies on to survive in the coming centuries. We were too slow to act on climate change.
- vesinisa 6y ago> it’s not popular because it’s not needed right now Dubai, a wealthy city of four million on Persian Gulf surrounded by the vast Arabian Desert, sources its water almost exclusively through desalination.
- shakezula 6y agoYes, that’s still not popular by definition though. I understand that non-trivial amounts of water are being provided to major city centers via desalination. I’m saying that there’s a good chance that on century long timelines, we’ll be almost entirely dependent as a species on desalination to provide our fresh water. Even our most aggressive climate models aren’t keeping up with reality. This is a problem where even incremental advancements are important given our current situation.
- canofbars 6y agoIn my state of Australia someone has built a massive desal plant in the middle of the desert next to a salt water source, the whole thing is powered by an array of mirrors and then the water is used to grow a huge tomato plantation in what would be totally unusable land without having to pipe in water. The pic is super cool https://en.wikipedia.org/wiki/Sundrop_Farms#/media/File:160411_Whole_Site_Aerial.jpg https://en.wikipedia.org/wiki/Sundrop_Farms#/media/File:1604...
- shakezula 6y agoOh man this is super cool! I've never heard of this but this is exactly what I think the future will require. Being able to create your own power and then desalinate it and use it to grow crops in the same space is crazy powerful. I wish them all the best luck.
- williesleg 6y agoI'm afraid there isn't enough fresh water to feed everyone on the planet
- sweetdreamerit 6y agoCan I ask a very naive question? Isn't it viable to use solar energy to make the water evaporate and use the vapor as the desalined water? I'm sure there should be some big issue, otherwise someone would use it. But I'm curious to understand what is wrong with such an approach.
- scsilver 6y agoYou could take a long and wide but short pathway of water with a tilted glass top and a black floor. The light is absorbed by the black floor, heating the floor then the water. Water evaporates to a vapor which leaves the salt behind. It then will condense on the tilted class ceiling and run down to a storage tank for consumption (You can also get a warm shower using this lowtech solar method.
- canofbars 6y agoNothing is wrong with it. Here it is in action here powering a tomato plantation in the middle of the Australian desert https://en.wikipedia.org/wiki/Sundrop_Farms#/media/File:160411_Whole_Site_Aerial.jpg https://en.wikipedia.org/wiki/Sundrop_Farms#/media/File:1604... Interesting fact is these are not PV solar panels but simple mirrors redirecting the suns energy at one point.
- Already__Taken 6y agodown sides beginning you need to keep the mirrors cleaner than you do solar panels. Bird's that fly though the focused beam die. the sun has to be tracked, though I don't know if that's any different from a normal panel farm tracking the sun.
- wolfretcrap 6y agoIt's the power consumption I guess. I've membrane filtration at home, it consumes very little power than what you'd need to boil the water and condense it to water again. I've tried it on my solar panels, getting even 5 liter of water on my 2x350w panel takes 3-4 hours while I get 5 liter water from RO membrane in 1 hour while using 5% of solar panel power.