COMMODITY SALT What are salts?

WHAT ARE SALTS?  Formal name for NaCl is Halite  Chemically defined as reaction between Na, Cl and H2O to form NaCl or compound of metal and non metal  Greek word ‘hals’ means salt Salt – crystalline compound NaCl.  Salt-halite – colourless to yellow, but may be light blue, light blue and pink  Pure NaCl contains by weight 39.34% Na and 60.66% Cl  NaCl sometimes known as common salt or table salt  Salt was used as currency to soldiers in the Roman society

PROPERTIES OF SALT  Colourless to white but sometimes red, blue and purple  Exhibit isometric  Refractive index of  Hardness of 2  Cell contents is Na4Cl4  Perfect cleavage  Specific gravity of  Melting point of 804 degrees Celsius(1,479F)  Boiling point of 1,413 degrees Celsius(2,575F )

MINERAL PHOTOS - SALT Mii Photos Halite (Sodium chloride--Salt)

GEOLOGIC DESCRIPTION - SALT  Deposits are either in solution or in solid state  Bedded Salt Deposit : Deposit is associated with sedimentary rocks such as limestone, shale, dolomite and anhydrite.  Salt Domes : formed as a results of deposition of restricted marine basins, over period of time salt is then covered with sediment and becomes buried.  Lakes: Formed as a results of natural accumulations of water in topographic depression.  Groundwater: Formed either by connate or meteoric water. Examples are chloride-sulphate, chloride-carbonate, sulphate- carbonate and acids.  Solid Salt : They are found in playa lake deposits, bedded salt deposit and salt domes.

MINING - SALT  Rock salt is mined using room-and-pillar method of UG mining. - U.S and Canadian rock salt mine used this method.  Salt can be produced by controlled evaporation of seawater or brines in salt lakes. -This process is used at Great Salt lake in Utah- U.S  Vacuum pan process, this uses mechanical evaporation technology - Salt is obtained by dehydrating brines using heat or in combination with a vacuum.  Salt is produced in most countries on earth.

PRODUCTION - SALT  Oceans – 42% of salt is dissolved in oceans  U.S - produces about 1/5 of the world’s salt  U.S - also import about 1/5 of her salt from other countries.  In U.S. 40% of salt is used in chemical industry and another 40% as a de-icer on roads during winter  U.S. table salt account for only 1%

PRODUCTION - SALT Cont.

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USES - SALT There are numerous uses of salts in the world, the following includes some of the uses.  Food seasoning and food preservation  Canning process- use as flavour enhancer and preservative  Baking- use in baking industry to control rate of fermentation in bread dough  Preparation of sodium hydroxide, soda ash, caustic soda, chlorine, hydrochloric acids.

USES - SALT cont.  In oil and gas exploration- drilling fluids  Textiles and Dyeing- as brine to separate organic contaminants  Use in the manufacture of neoprene rubber, white rubber and other plastics.  High way de-icing- use to melt snow and ice on roadways

FORMULA- Other uses

SUBSTITUTES - SALT  No economic substitutes for salt  Calcium chloride and calcium magnesium acetate, hydrochloric acid and potassium chloride can be substituted for salt but at higher cost.

REFERENCES - SALT 1. Barker, J.M., Kogel, J.E., Trivedi, N.C., and Krukowski, S.T., 2006, Industrial minerals and rocks, 7 th Edition USGS, Minerals Commodity Summaries, January USGS, Minerals Yearbook