|MadSci Network: Chemistry|
If done properly, there would be almost no danger. If taken from clean seawater, the only products will be "fresh" water and concentrated salt water. The salty water can be used as a source of commercial salt or as a starting chemical for other processes. It could also be returned to the ocean where it came from. The increase in salt for the ocean would be zero because the ocean is so big. The only thing I can think of would be if the salty water was dumped on land, whcih would cause problems for the soil and fresh water sources.
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