All About Salt

     Salt....on the roads, in the ocean, in our bodies, on our food.  So important that migrations of people throughout history have revolved around it's location in the earth.  The average adult body contains about 160 to 175 grams of salt.

         While salt is not made, the "manufacture of salt refers to the harvesting and purification from natural sources.  The oldest method of harvesting salt is the simpl evaporation of seawater.   While seawater certainly tastes very salty, it only contains about 3.3% by mass salt on average.

         Typically, physical mining of salt or solution mining is used "manufacture" salt.  While seawater evaporation is also popular, vast amounts of space are needed for the evaporation ponds.  This method is also constrained by the rate of evaporation, but this is not really a problem in tropical areas.  Solution mining is becoming very popular due to it's simplicity and high level of safety when compared with traditional mining of salt.

     The brine exiting the ground can be run through evaporation systems to concentrate the brine, then crystallization can be used to harvest high purity salt.  It may surprise you to learn that about 75% of the salt harvested is used to produce other chemicals.  Mainly chlorine, hydrochloric acid, and sodium hydroxide.  The popular chloroalkaline process uses salt to manufacture chlorine and sodium by applying an electrical charge to brine solutions which causes the salt to ionize.