ABSTRACT
Potash production from ore deposits started in the mid-nineteenth century shortly after Liebig’s discovery that potassium is an essential element in plant nutrition. Since relatively uncontaminated sylvinite ore is the most abundant type worldwide, continuous miners are used in all major potash mining districts. The remaining 8%, in descending order of usage, consists of potassium sulfate in relatively pure form or combined with magnesium sulfate, potassium nitrate, and potassium phosphates. Refining methods for the production of muriate of potash from naturally occurring ores are based on the physical and chemical characteristics of the ore and to a lesser extent on the quality of potash products to be produced. Some potash plants have installed sufficient compaction capacity to convert all of the muriate produced in the primary refining operations to granular product. In general, potassium sulfate production involves exchanging the chloride component of the muriate of potash with the sulfate component of sulfuric acid or magnesium sulfate salts.
