how can seawater be desalted? desalted?

Answer 1

The above methods all work to varying degrees of efficiency but with several limitations for high volume de-salination. First, that one method would require a LOT of POTATOES. The solar method takes an extremely large solar evaporator and of course doesn't work so well at night. Reverse osmosis units work best in converting brackish water to potable water, but the typical unit output capacities are dramatically less for converting ocean water to fresh.

Norrie described reasonably well an industrial desalination plant. Normally, the designs are slightly better described as a multi-stage, flash type distilling unit. Through clever design they re-capture as much "waste heat" as possible and use it to pre-heat the incoming saltwater feed system to increase energy efficiency. The multi-stage chambers (between 2 and 9) are separated by vacuum loop seals into progressively greater and greater vacuums. Essentially, when saltwater pre-heated to approx 145F enters a chamber of severall inches Hg vacuum, some of it instantly "flashes" into freshwater distillate, while some flows to the next stage where it "flashes" again. Very highly salted brine collects in the bottom of the chamber, while the freshwater distallate is collected in the upper part of the chamber. In this manner, the heat efficiency is maintained by not trying to convert ALL the saltwater into freshwater, but only a small fraction in each subsequent stage. Most large industrial desalination units operate in some manner close to this.

But I do like the potato method. I've used it to de-salinate my home-made soups on many occasions.

Answer 2

you can desalted the seawater by desalination process
where you evaporate the seawater and passing it to hollow cylinder pipe where the heat is exchage betwwen the vapor and the cold water causing the condensation of vapor and then forming fresh water which called destilate water and the salt or brine keep in the first contanior.

Answer 3

Do you want a quick and easy way or the long drawn out way? Quick and easy is boil the seawater, but that takes up a lot of energy. They are working on desalination techniques to make seawater drinkable, stuff like reverse osmosis, but that's such a broad topic you could write research papers on it.

Answer 4

Following is a basic explanation of a Desalination process.
Industrial Desalination Plants are used in regions of little fresh water availability.
The plant is a Distillation unit consisting of a 'Vaporiser' vessel which is maintained under high vacuum by a system of steam ejector sets (using Venturi Tubes and superheated high pressure steam and surface condensers to create the vacuum).
Sea water is passed through the vessel which contains large heat exchange tube bundles within the vessel. The tube bundles have superheated steam passing through them and exchanges heat with the salt water flowing through the vessel.
Due to the vacuum, the water boils at around 65°C (150°F) and produces pure steam which is pulled out by the ejector units.
The steam leaving the ejectors is condensed in surface condensers being cooled by the incoming sea water feed to the plant.
This, by heat exchange principles, effectively pre-heats the salt water, thereby decreasing heat requirements needed in the distillation process and, condenses the produced steam which goes on to further cooling systems and to storage tanks as pure, fresh water, some of which goes to the boilers producing the superheated steam, while the main product goes to domestic and industrial use.
The sea water flowing through the unit has a constant, controlled, flow with the outlet, now higher in salt content, being returned to the sea to a location well away from the source water area to prevent treated sea water mixing with the supply source.

Answer 5

Destillation, ion exchange, reversed osmosis. There are several ways. Evaporation in a glass structure using sunlight only would be the most efficient way. That is how nature produces freshwater.

Answer 6

You would have to make an apparatus that you could evaporate the water, but still have the water vapor collect somewhere else so that you could then cool the water and it would "rain" back fresh water

Answer 7

Most efficient is osmosis

Answer 8

By dumping a lot of potatoes in it! =)