Every day, each of the earth’s 5.9 billion inhabitants uses salt. Annual salt production has increased over the past century from 10 million tons to over 200 million tons today. Nearly 100 nations have salt producing facilities ranging from primitive solar evaporation to advanced, multi-stage evaporation in salt refineries.
Humans need salt to live. Prehistoric man obtained salt from the meat of hunted animals. When man developed agriculture, salt was added to supplement the vegetable and cereal diet and the quest for salt became a primary motivation in history. In the mid-1800s, salt’s value as an important raw material for the chemical industry was established when the Solvay process in Belgium converted salt to synthetic soda ash. Salt is, today, the largest mineral feedstock consumed by the world chemical industry. A summary of a 1997 book, The Economics of Salt, is available online.
North America produces more than one-quarter
of the world’s salt.
The U.S. salt industry began in 1614 when the first non-native solar saltworks was established by the Jamestown colonists on Smith’s Island, VA. The U.S. is the world’s largest salt producer, producing 41.3 million tons a year, nearly half of that, 21.1 million tonnes, in the form of brines produced by captive brine wells supplying U.S. chloralkali chemical companies. The remaining 20 million tons is “dry salt” produced using three basic technologies: solar evaporation of seawater or saline lakewater, solution mining and vacuum pan evaporation and conventional deep-shaft (rock salt) mining. Some other countries like Bolivia and Mali, use “low-tech” solutions such as simply scraping salt from the surface of anciently-evaporated salt lakes. Currently, the U.S. salt industry operates 48 salt production plants with major production sites in Louisiana, Ohio, New York, Kansas, Michigan, Utah and California. All major U.S. salt producers are members of the Salt Institute. U.S. salt production is also tracked by the U.S. Geological Survey, including an interesting review of saltmaking at the Great Salt Lake in Utah.
The Canadian salt industry produces 13.32 million metric tonnes from major rock salt mines in Ontario, Quebec and New Brunswick and vacuum pan refineries in Alberta, Saskatechewan, Ontario, New Brunswick and Nova Scotia; nearly three-fourths was rock salt which is used primarily for highway deicing.
Mexican salt production totalled 8.412 million tonnes, most of it from the world’s largest solar facility in Guerrero Negro in Baja California