Ammonium sulphate - the waste or fertilizer?

Ammonium sulphate was known as a fertilizer as early as in the 20th century. It exists on the market mainly as a by-product being generated, for instance, in the caprolactam or coke production, and in the flue gas desulphurization. Its fertilization usability is determined by two available mineral components - viz. ammonia nitrogen and sulphate sulphur. As recently as in the 1990s ammonium sulphate existing on the market provided a lot of difficulties in its disposing. The shortage of sulphur in the soil, the problem which has existed for several years, has changed the position of ammonium sulphate from the troublesome waste into a valuable fertilizer.