6 ms·
Do you get enough volume for this to work? My intuition would be the levels of Uranium would be low enough that it would not be energy positive. Do you have m
by enkid 6y ago
Do you get enough volume for this to work? My intuition would be the levels of Uranium would be low enough that it would not be energy positive. Do you have more information about this process?
- jbay808 6y agoI remember some projects going on at MIT on this topic. https://dspace.mit.edu/handle/1721.1/111821 https://dspace.mit.edu/handle/1721.1/111821
- 08-15 6y agoEnergy consumption of reverse osmosis is about 4kWh/t. The byproduct is a ton of brine. Sea water contains about 3ppb Uranium, so our brine contains 6mg of U per ton of fresh water produced. A 1GW nuclear power station consumes about 1t of U per year and produces about 8000GWh of electricity in that time. So we need about 1mg/8kWh. We got 12 times that much. So, it sort of works out. Of course, this assumes a breeder reactor and I pretended that brine is purified uranium. If breeders are commercialized, it might be worth looking into this. Right now, it isn't.
- enkid 6y agoAwesome, thanks!
- credit_guy 6y agoNice analysis. But the premise of the discussion here is that people do the desalination for its own sake, not in order to harvest Uranium. This [1] article from 2012. It presents a Uranium extraction method from seawater that would put the extraction cost at $300/kg. Nowadays the market price is about $70/kg. However, if method were to be applied to brine instead of regular seawater, maybe the cost would go down. Hard to see it going down by a factor of 5 though. [1] http://large.stanford.edu/courses/2012/ph241/ferguson2/ http://large.stanford.edu/courses/2012/ph241/ferguson2/
- vilhelm_s 6y agoI think you overestimate the energy in uranium. 8000GWh per tonne and year would be 28.8 TJ/kg, while the numbers I have seen is more like 0.7 TJ/kg (http://www.plux.co.uk/energy-density-of-uranium/ http://www.plux.co.uk/energy-density-of-uranium/).
- wolfhumble 6y agoSo 4kWh/t is used to desalinate 2 tons of seawater that turn into 1 ton of freshwater and 1 ton of brine?
- vilhelm_s 6y agoGoogling a bit: it takes about 13 MJ to desalinate 1 m^3 of water by reverse osmosis. Seawater contains 3mg uranium per m^3, which gives 2 MJ, So it's not energy positive.
- lxmorj 6y ago2/3rds power rebate on your desalination ain’t bad!