Sounds pretty cool. I wonder whether it would still filter out other contaminants? I think many are smaller than salt molecules. At the least, it should make a good prefilter to allow the RO to last longer.
I don't think it will be much different than the TFC or thin film composite RO membranes we use today. A TFC membrane is made up of a perforated fabric or sheet that is wound around a central core but the fabric is much thinner than a sheet of Glad or Saran plastic wrap. The author makes a membrane sound huge which is misleading.
The other similarity is you will still need a way to flush the brine away same as with RO and the waste ratio we use today to do so. Normally low pressure treatment is MF or microfiltration or UF or ultrafiltration so its several steps below NF or nanofiltration and RO or reverse osmosis. While all can make water suitable for human contact or human consumption not all will remove the TDS to levels we all like to see as pretreatment for our DI or deionization resin so it lasts a reasonable length of time.
There are developments in membrane technology constantly, 20 years ago it required 250 psi pumps to achieve what we do with 40 psi household pressure today. We have gone from the old CTA or acetate membranes to todays TFC membrane materials which has been a big improvement. Carbon technology has improved tremendously with the steam extruded solid carbon blocks and ability to combine multiple carbon types and structures in one block so it performs well with not only chlorine but many other contaminants also. Resins are constantly being improved with much longer lives wth shorter contact times.
In the wastewater industry we use hollow fiber meembranes similar to a long bundle of spaghetti or membranes installed in plates or sheets on which we pull a vacuum and draw contaminants in that way then use bursts or air to cleanse them. All fairly new technology in the grand scheme of things when you consider membranes have really only been common in the last 25-30 years, well after I started my water treatment carrer. Dang, that makes me feel old!
Water treatment technology has made been some pretty great advancements in the couple decades. In this case they I believe they are using Graphene, which was developed at MIT. I remember reading this article about a year ago.. so it looks like the technology is beginning to trickle down. Should be good news for pressure requirements, filter life, and more. More of an upgrade than an end to
Another study and company is using teflon for membrane material. There are many parallel studies going on. When you work in the industry you sort of take it for granted but we see these all the time and my firm even participates in many of the studies as we have some of the top membrane experts in the world on staff. They start talking and my eyes glaze over....... Way over my head!
Like all industries everything is the "Big Race", so you see alot of things come and go, but one thing that has caught my eye is fluorographene. I really feel like with enough research & funding that fluorographene could be a serious competitor if not replacement for teflon. Fluorographene with its unique properties has some pretty amazing potiental and something I'll be keeping an eye on for sure, not just for water filtration but the many other applications it would be useful for.
The end to RO/DI ?
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