Potash

"Potash" includes a group of potassium, chemical symbol K, bearing salts and chemicals. During ancient times, soluble potassium was used as a fertiliser, derived by soaking wood and plant ashes in large iron pots. Potassium was filtered from wood ashes and then concentrated by evaporating the solution in big iron pots. Thus, it derived the name “Pot-Ash”.

Potash deposits have different concentrations of potassium; hence Potassium oxide (K₂O) equivalence is used in the industry for consistency. However, potassium chloride (KCl) is the most produced form of Potash.

Uses of Potash

• Potash is majorly used as a fertiliser, approximately 95%. It increases crop yield, supports and enhances growth, protects crops from diseases, and enhances water preservation in plants.
• Small quantities are also used to manufacture potassium-rich pharmaceutical chemicals, glass, soaps, explosives, etc.
• Potassium is required for normal cell function and optimum human body growth. It also helps in the maintenance and development of human organs and tissues.
• It also plays an important role in the electrical activity of the heart. For an average adult, approximately 2 grams of potassium is required per day.

Global Potash Distribution

Potassium is the seventh most abundantly available element in the earth's crust. Clay minerals are categorised as good sources of potassium, containing as much as 17% potash.

Potassium occurs naturally in rain in a very small quantity of about four parts per million, while the concentration in seawater is approximately 390 mg/l of potassium.

Canada is the world’s largest potash producer, contributing around 32% of total global production, followed by Russia, Belarus and China. Cumulatively, these four countries were responsible for about 80% of global potash production as of 2020.

Potash Mining Techniques

Two mining techniques are used to extract potash from the subsurface: solution mining and conventional underground mining.

Solution mining is used where potash deposits are much deeper in the earth's crust. Water or brine is injected into the ore body via wells, and water-soluble potash gets dissolved in the injected water or brine. This solution of dissolved potash is then pumped to the surface facilities, where potash is recovered through recrystallisation.

Conventional underground mining is a traditional method which involves boring machines digging out the ore, which is then crushed and refined in the processing mill to extract potash.