How Do They Clean Mined Salt?
Mined salt undergoes a refining process to remove impurities and create the various types of salt we use. The process differs slightly depending on the source (rock salt vs. evaporated salt), but generally involves these steps:
- Brine Extraction/Mining: Rock salt is mined, while salt from seawater or salt lakes is dissolved to create brine.
- Brine Treatment: The brine undergoes treatment to remove impurities like minerals and other unwanted substances. This often involves various filtration and purification techniques.
- Evaporation: The treated brine is pumped into vacuum pans – sealed containers where the water is boiled off, leaving behind the salt crystals.
- Drying and Refining: The salt crystals are then dried to remove any remaining moisture. Further refining steps may be included to remove additional impurities and achieve the desired crystal size and texture.
- Additives: Depending on the intended use (e.g., table salt), iodine and anti-caking agents may be added.
Example: As mentioned in one reference, "At the plant, the brine is treated to remove minerals and pumped into vacuum pans, sealed containers in which the brine is boiled and then evaporated until the salt is left behind. Then it is dried and refined." This outlines the core process for purifying salt from brine.
Different Salt Sources, Different Methods: While the core principle of removing impurities remains, the initial steps vary. For sea salt, harvesting and initial cleaning may involve techniques like washing and sun drying to remove larger debris. Rock salt mining requires crushing and processing before the brine is created.
