Sodium chloride, commonly known as salt, is one of the most abundant minerals on the planet. Salt possesses major economic importance because of its usefulness beyond flavoring and preserving food. In fact, according to the February 2019 U.S. Geological Survey, of the 42 million tons of domestic salt produced in 2018 only 6% of salt was used in agriculture and food processing while 43% of the salt consumed in the United States was for de-icing purposes. These numbers don’t include imported bulk salt which is estimated to be around 18 million tons.
Bulk industrial salt is also a key proponent in manufacturing products like paper, plastic, synthetic rubber, glass, soaps and detergents, polyester, and much more. Over half of the products in the chemical industry rely on salt during a manufacturing stage. In addition, salt is used in textile dying and for tanning animal hides on a large scale.
Other industries that utilize bulk industrial salt is the drilling and pharmaceutical industries. During drilling, sodium chloride is used to increase the density of mud and soil, stabilizing the walls surrounding a drill bit to prevent the collapse of the hole. Pharmaceutical companies use salt to make capsules and create saline solutions to treat patients. All very important uses to achieve the way of life we have grown accustomed to.
Another usage of salt is for the treatment of ‘hard water’, which is water that contains calcium and magnesium. Water softener salt removes calcium and magnesium from a water supply, preventing pipe blockages, appliance damage and improving water quality.
Because bulk industrial salt is so useful there are problems, the main one being that sodium chloride after usage becomes a pollutant that negatively impacts ecosystems.To reduce the salinization of waterways, product manufacturers rely on wastewater treatment systems to disinfect the water, remove the unwanted elements like salt, and recycle the water for other uses throughout a facility, thus lowering the impact on the environment. The drilling industry recycles as much saltwater as possible, returns the water to the reservoir via fluid injection, and stores the saltwater in disposal wells that operate under regulatory guidelines.
Municipalities help reduce the environmental impact of sodium chloride by constructing central water treatment plants that treats hard water before it reaches residences. Lime softening technology also removes minerals from hard water, but doesn’t dispose of the minerals in sewage treatment areas. Another water softening possibility that cities can use is split treatment with reverse osmosis, which relies on a membrane that removes the most miniscule of particles from water.
Liquid ice melt could be the best use of chlorides for winter ice management. Not only can you make a larger area safe with less chlorides than ever, the efficiency of the chlorides that are applied far surpasses solids. Municipalities across the snow belt have begun implementing liquid ice melt to keep roads safe. Private contractors and property managers have also begun switching to the much more responsible methods of winter maintenance with liquid ice melters.
On an individual level, homeowners with hard water can help the environment by upgrading to a more efficient water softener and by using less salt in the softener. Potassium chloride is another, safer alternative to sodium chloride that can be used in a water softener.
Our numbers for this article were taken from the USGS website.