Sodium chloride (salt) is one of the largest-volume inorganic raw materials used by the chemical industry. The major chemical products of salt—chlorine and caustic soda—are in turn used in the manufacture of many chemical products, both inorganic and organic. Salt is also used directly for snow and ice control, as a mineral in animal diets, as a food preservative and flavoring agent, as a reagent for water softening, and in many industrial processes.
China has been the leading producer of salt since 2006. In 2012, China's production accounted for about 28% of global production. The United States is the second-largest producer of salt, with an estimated share of about 15%. Other major producers include India, Australia, Germany, Canada, Mexico, Chile, France and Brazil.
The following pie chart shows world consumption of sodium chloride:
Chemical production accounted for over half of all salt use globally. The second-largest consuming segment (14% in 2012) is road salt for deicing. Consumption for deicing can vary substantially from one year to another, depending on climatic conditions. Use in food, including household (table) salt, use in bakeries, and for preparation and preservation of food, accounts for about 12% of all salt consumption. There are a variety of other uses—water softening, animal feed, industrial and medical applications—that together account for the remaining 19%.
Chemical plants may consume salt in the form of brine, rock salt, solar salt or very-high-purity grades of granulated-evaporated salt as a raw material. In many instances, particularly in chlor-alkali production, the grade used can be flexible, and the feed salt is purified to the required grade prior to use. The world's largest brine production operations are typically owned by vertically integrated chlor-alkali producers that captively produce their own salt supply as salt in brine.
The world's second-largest market for salt, deicing, relies primarily on mined rock salt with no purification required. Temperate countries with the largest rock salt production, such as Canada, Germany and the United States, also tend to have large domestic deicing needs. In these countries, rock salt is the most inexpensive, acceptable grade of salt. It is used near its site of production; the transportation expense is minimized and thus rock salt is highly competitive in the deicing market. Depending on winter conditions, North America and Europe import smaller or larger amounts of salt from nearby low-cost producing regions like Chile and North Africa.
Salt is available in most countries and regions of the world and is sold at a relatively low price, so trade would be expected to take place only in exceptional cases. And yet, more than 10% of all salt produced and consumed in the world is traded over large distances. The main salt importers are China, Japan and Other Asian countries, with the imported salt consumed mainly in the chemical industries of these countries. The primary exporters are countries with climatic and geographical conditions that allow for reliable low-cost production of solar salt—Australia, India and Mexico—as well as Chile with its low-cost production of lake salt.