33

What does it take to reduce the salinity? The salinity of sea water is around 35 g/kg. There are around 1,350,000,000 km³ of water, so roughly 1.3x1021 kg of seawater (1 kg/l, which is a bit off for saltwater of course, probably by 35 g). Which contains about 4.7x1019 kg of salt. To reduce the salinity to just 34 g/kg, you need to extract 1.4x1018 kg of salt ...


19

The residue dry powder you refer to is salt. Salt is toxic to most plants. The United Nations claims the world is already losing 2000 hectares per day of farm land to salt-induced degradation. This is land that is used to feed people. In some situations, salt from affected lands can contaminate underground sources of drinking water, which will affect people, ...


9

The oceans are salty because the slightly acidic rainwater dissolves minerals from ores and rocks and runs into the sea. This is a continual process, a consequence of erosion. However, the salinity of the oceans has been stable for millions of years, indicating that there is an equilibrium between processes in both directions. Salt is removed from the oceans ...


2

Desalination of ocean water costs energy; beside fresh water, you gain salt. With some additional energy invested, you could purify this salt consisting to large extent of sodium chloride (NaCl) which may be used as table salt. In other places, you mine for rock salt from underground mines, and equally perform a purification of salt, yet without the ...


1

Think of what happens with the fresh water that we extract via desalination. It's used for drinking, general water supply, farming and some other industries. In either case it will either eventually evaporate and eventually end up in the ocean or it is discharged back into the ocean. Some water is of course lost in the process, but it's a relatively small ...


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