OTHER INDUSTRIAL USES OF ROCKSALT
ROAD SALT
The main use for rock salt is for managing ice; both residential and on a large industrial scale.
Ice forms when the temperature of water reaches 32 degrees Fahrenheit (0 degrees Celsius). When you add salt, that temperature drops: a 10-percent salt solution freezes at 20 F (-6 C), and a 20-percent solution freezes at 2 F (-16 C). On a roadway, this means that if you sprinkle salt on the ice, you can melt it. The salt dissolves into the liquid water in the ice and lowers its freezing point.
During the winter months it is very common for homeowners to spread salt on their walkways and driveways after a snow storm to melt the ice. It is not essential to use so much salt that the ice is completely melted; but instead, using a small amount of salt will weaken the ice sufficiently so that it can be easily removed by alternative means
WATER SOFTENER
Water is considered hard when it contains calcium and magnesium (hardness ions). Hard water requires more soap and detergent for laundering, cleaning and bathing because suds do not form as well in hard water. The reaction between soap and hard water results in a greasy, curd-like deposit which makes fabrics feel harsh and leaves water spots on dishes and utensils. Mineral scale builds up in hot water appliances and industrial boilers, reducing energy efficiency and shortening appliance and equipment life. Water is conditioned or softened by removing the calcium and magnesium ions from hard water and replacing them with "soft" sodium ions. Water softeners use cation exchange resin to exchange sodium for calcium and magnesium. As supply water flows through the resin bed, the exchange takes place and the water becomes soft. Water softener cation exchange resins are regenerated with a 10% salt brine solution made by dissolving water softener salt.
A small water-softener is built into every dishwasher. This works approximately as a classic water-softener and ensures that your dishes do not suffer from the effects of hard water.
Dishwasher salt ensures that your machine stays well-maintained and your dishes dazzle. Salt for the dishwasher is extremely pure and has large, hard grains.
SALT FOR SWIMMING
POOLS
Salt belongs in a swimming pool for two reasons. First and foremost, the correct concentration of salt in the water makes for a pleasant swim: no stinging eyes, no dried out skin afterward. In swimming pools operating with salt electrolysis, salt is also required to produce chlorine and ozone. That keeps the water pure and inhibits the growth of bacteria, algae and other nasties.