Ammonium Sulphate (S)
Granular ammonium sulphate (20.5-0-0-24) is made by combining ammonia and sulphuric acid in a pipe reactor, to produce an ammonium sulphate solution. The solution is sprayed into a granulating drum where the fertilizer granules are formed.
Potash deposits (0-0-60) occur in beds of sediments at only a few locations around the world, the largest is located in Saskatchewan, Canada. This deposit which has a thickness from 2.7 m (9 ft.) to 23.5 m (77.6 ft.) is found at depths ranging from 1000 m (3,200 ft.) to 3000 m (10,000 ft.) below the surface.
Solution mining methods are used to extract potash from deeper depths. Conventional underground dry-shaft mining methods are utilized in mines up to depths of 1100 m (3500 ft.). Ore is extracted from the potash deposits by electrically operated mining machines and conveyed to the surface where it is crushed. Using a flotation process, common salt and clay particles are removed, the brine solution is dried, and the dried potash is then sized by screening. The resultant coarse grade product is ready for distribution. Fine particles remaining from the screening process are compacted into sheets which are then crushed and screened to particle sizes suitable for blending.