In drought conditions, is there a way to use sea water for drinking purpose?
Looking for least expensive household treatment.
For least expensive option, research solar stills.
The daily volume is relatively small but they are generally passive systems with production dependent on daily solar exposure.
Large volume production is another question.
If you are talking about the conversion of a huge amount of sea water into drinking water, then one of the best solution is to use nuclear energy, particularly, small or medium size nuclear reactor, for this purpose.
Another possibility is to use the reverse osmosis process, used in El Paso's desalination facility in the USA.
In my opinion, reverse osmosis process may be a promising technology. In addition, in the Middle East, multi-stage flash which takes the solar as power is also a good measure.
For Large scale
RO and Multistage Evaporation are the 2 most economical
for all cases, RO is still the most economical option. For small scale plant ED could be an option; for very large scale plant and based on rawwater condition, thermal plants could be an option if waste heat is available to be used.
Again, in general, RO is the recommended option.
As an alternative, you could also evaluate pumping water from another locations where water is produced at lower cost.
In my opinion RO is the best option. Nowadays, reverse osmosis and distillation processes are the most used technologies. The required plant capacity, the annual and daily distribution of fresh water demand, the product cost, the technology maturity, and any problem related to the coupling of the renewable energy and the desalination systems determine the election. Please, look at Rodríguez L. G., “Renewable energy applications in desalination: state of the art,” Solar Energy, vol. 75, no. 5, pp. 381–393, 2003 for more information.
Also I think as RO is the best industrial large scale option, but some solar systems are being developed with good efficiency and high purity grade to produce drinking water. Systems using high humidity ratio moisture captured over sea water films and than cooling this moisture in the surrounding could provide this desalinated water.
Dear Tara,
Nice question.
At large scale, reverse osmosis is the most common choice to produce high quality water from seawater. If I understand correctly, your question relates to very small household treatment, meaning that costs per m3 water produced will be most likely much higher that the centralized large scale RO treatment.. Assume that this household should be located near the sea to have access to seawater.
Possibly a solar/wind powered system could be considered. Or a small RO system.
Best regards, Hans
Hello;
well , it may be strange, but I would really like someone trying this way to desalinate water...
for small purpose only; the cheapest way ever for sure!
https://www.facebook.com/pages/Effet-Dumas-Energie-libre/270688943092791?sk=timeline
What do you suggest the most preferable method for low income countries to solve salt problem from drinking water? I mean that rather than reverse osmosis and solar desalination what alternative methods are there?
Thank you Zenebe,
It is interesting that this topic keeps coming up. We should qualify what is meant by "low income" . The cost of membranes may prevent RO from even being a consideration. Steam/condensation is quite inexpensive to create from whatever materials may be on hand. If there is access to animal dung and biomass, it is also quite straight forward to make a bio-digester that will supply the fuel/heat input that drives that process. You disqualified solar desalination. Because of insolation limits? Because of its history of relative low production and high maintenance? I have seen Electro-Dialysis Reversing (EDR) run on solar panels and batteries producing 1000l/hour with little added cost beyond installation. (I grant you that the installation is quite expensive but that is a 1 time investment and membranes are quite robust) How much salt are you considering? Sea water? Is there tidal energy available?
Things to consider. thanks again for bringing the subject back.