Salt water is harvested using a process involving evaporation and collection of salt crystals.
Salt Harvesting Process
The primary method of harvesting salt from seawater involves using salt evaporation ponds. These are shallow, artificial basins specifically designed to facilitate the natural evaporation of water, leaving behind salt crystals.
Steps in the Process:
- Pond Creation: Salt evaporation ponds are constructed in shallow areas, often near the coast, where seawater or other salty water sources are diverted into the basins.
- Water Evaporation: The sun's heat causes the water to evaporate, gradually increasing the concentration of salt in the remaining water.
- Salt Crystallization: As the water continues to evaporate, salt begins to crystallize and form solid salt deposits.
- Salt Harvesting: Once the water is evaporated and the salt crystals have formed, they are harvested by raking. This involves physically gathering the salt deposits from the bottom of the ponds. (SF Fig. 2.4)
Alternative Salt Sources:
- While seawater is a common source, salt can also be harvested from salty lakes and mineral-rich springs. The process is similar to that used with seawater – using evaporation ponds to separate salt from the water source.
Key Tools and Techniques:
- Rakes: Rakes are used to gather the crystallized salt from the bottom of the evaporation ponds.
- Evaporation Ponds: These shallow basins are the primary tools for salt water harvesting as they maximize surface area for evaporation.
- Sunlight: The primary source of energy for the process is the sun which provides the heat needed to evaporate the water.
| Step | Description |
|---|---|
| Pond Creation | Artificial basins are created. |
| Water Introduction | Salt water is channeled into the basins. |
| Evaporation | Water is evaporated by the sun. |
| Crystallization | Salt begins to crystalize. |
| Harvesting | Salt crystals are collected via raking. |
Summary
Saltwater harvesting relies on natural evaporation in shallow ponds, where the salt is then raked for collection. This process effectively extracts salt from seawater and other briny sources.
