Salt

Molecular formula                                                               NaCl

Molar mass                                                                       58.44 g mol⁻¹

Appearance                                                                       Colorless crystals

Odor                                                                                Odorless

Density                                                                           2.165 g/cm³

 Melting point                                                                    801 °C; 1,474 °F; 1,074 K

 Boiling point                                                                  1,413 °C; 2,575 °F; 1,686 K

  Solubility in water                                                            359 g/L

  Solubility in ammonia                                                       21.5 g/L

 Solubility in methanol                                                      14.9 g/L

 Refractive index (n_D)                                                    1.5442 (at 589 nm) Structure

   Crystal structure                                                               Cubic

Nutrition Facts

Salt

 % Daily Value*

Brine springs and lake spreads are possible sources of crude salt in Nigeria. The concentration of salt in these springs has been estimated at 15 to 30 parts per thousand. The saline springs occur within the narrow belt which extends in a North-North East – South- South West direction from Gombe to Afikpo, along the plains of the Benue and Cross River drainage systems. Geographically, the brine occurrences in Nigeria have been divided into two broad groups.

i) North of river Benue: the Lafia Sale areas, which include:

1. a) The Azara-Akiri-Ribi Salt springs and the Awe-keana-Kenge salt speings;
2. b) The Mutum Daya, Gyakan, Todi and ayaba salt springs in Adamawa/Taraba States;
3. ii) South of River Benue : the Abakaliki – Okposi salt areas, which include:
4. a) Enyigba, Ameri, Ameka, Ikwo-abakaliki in Enugu State;
5. b) Okpoma, Gabu, Ijegu, Onyi near Ogoja, Cross River State;
6. c) Akwana, Arufu and around Takum in Taraba State; and
7. d) Uburu Ugwaneke, Afikpo in Ebonyi State

Most of the brines contained high proportion of sodium chloride, with subsidiary amounts of sulphate, nitrates and bicarbonates. A total reserve of about 1.5 billion tones has been estimated.

The Benue trough is also an attractive area for exploration for sedimentary salt deposit. Based on geophysical survey by Nigerian Mining Corporation, a saline lenticular structure of about 600m thick under over burden of 1,500m in the north west of Makurdi (called Oku-Lake) has been explored.

Salt is produced by evaporation of seawater or brine from sources such as brine wells and lakes, and by miming rock salt, called halite.

After the raw salt is obtained, it is refined for purity and improves its storage and handling characteristics.

Purification usually involves recrystallization.  This involves treating the brine solution with chemicals that precipitate most impurities (largely magnesium and calcium salts).

Multiple stages of evaporation are then used to collect pure sodium chloride crystals, which are kiln-dried.

It is common to add a trace of sodium hexacyanoferrate to the brine to act as an anticaking agent through the promotion of irregular crystals.  Other anticaking agents (potassium iodide, for iodised salt) are generally added after crystallization.  These agents are hygroscopic chemicals which absorb humidity and keeping the salt crystal from sticking together.

The refined salt is then ready for packaging and market.

Apart from the familiar uses of salt in cooking, salt is used in many applications. These include; manufacturing pulp and paper, setting dyes in textile and fabric, and producing soaps and detergents.  Salt is sometimes used as cheap and safe desiccant due to its hygroscopic properties, making it an effective method of food preparation.

Refined salt, which is most widely used presently, is mainly sodium chloride.  Food grade salt accounts for only a small part of salt production in the industrialized countries (3% in Europe), although worldwide, food uses accounts for 1.7% of total salt production.  The majority is sold for industrial use.

Salt has a great commercial value, because it is a necessary ingredient in the manufacture of many products.  The world top five producers are United State, China, Germany, India and Canada.

Nigeria with a population of over 180 million is surely a potential market for salt production.

Report from the Nigeria Geological Survey Agency indicates that Nigeria spends $2.3 billion to import salt every year.  Nigeria’s per capita consumption of salt varies between 2.2g and 6.3g daily with  an estimated consumption of 600,000 metric tonnes  for household, animal and industrial uses per annum

The National Salt Company(NASCON) is the major producer of salt in Nigeria. The company produces edible salt (for industrial use) and sachet salt fortified with iodine for domestic use. With a large population and industries utilising both table and industrial salt, investors in salt processing are required to bridge the demand gap.