How do you extract salt from seawater?

The simplest method to extract salt from seawater involves solar evaporation.

Here's a breakdown of the process, based on the provided reference:

1. Collection: Seawater is channeled into shallow pits or ponds. These pits maximize surface area for evaporation.

2. Evaporation: Sunlight naturally warms the water, causing it to evaporate over several days.

3. Salt Crystallization: As the water evaporates, the concentration of salt increases until it reaches saturation. At this point, salt crystals begin to form and precipitate out of the solution.

4. Harvesting: Once all the water has evaporated, a layer of solid salt remains in the pit. This salt is then collected.

5. Purification: The harvested salt often contains impurities. To obtain pure sodium chloride (NaCl) suitable for consumption, the salt undergoes further purification processes. This may involve washing, recrystallization, and the addition of anti-caking agents.

Step	Description
Collection	Seawater is directed into shallow, open-air pits.
Evaporation	Solar radiation heats the water, causing it to evaporate.
Crystallization	As water reduces, the salt concentration increases, leading to the formation of salt crystals.
Harvesting	The solid salt is gathered from the evaporation ponds.
Purification	The harvested salt undergoes further processing to remove impurities and make it safe for consumption as pure NaCl. This can include washing, recrystallization and anti-caking agents.