Keywords: Granular ammonium sulfate, Process development.

This paper traces the development of ammonium sulfate production and granulation techniques using examples drawn predominantly from the North American and Australian experience.

The use of ammonium sulfate as a nitrogen source became popular because of the abundant source of by-product material. Higher analysis granular forms of nitrogen, such as urea and ammonium nitrate, have now dominated the nitrogen market leaving ammonium sulfate to supply areas where sulfur deficiencies are common. Most ammonium sulfate produced is still by-product crystalline material. Only a small proportion of world supply is made synthetically, but granulation techniques based on synthetic manufacture, have produced superior quality product. The future will see the application of these granulation techniques to by-product ammonium sulfate, displacing traditional crystallisation techniques.

A M Brown and L A Hollingworth, Incitec Ltd, Brisbane, Australia.
M Fischbein, Esso Chemical Canada, Edmonton, Canada.

23 pages, 4 Tables, 3 Figures