Sable Chemicals

Located in Kwekwe, Sable Chemical Industries Limited is Zimbabwe's sole manufacturer of nitrogen-based fertilizer, ammonium nitrate (AN).

The company was incorporated in 1965 and started operations in 1969 using ammonia, a key raw material in the fertilizer making process, which at that time was imported through Sasol, South Africa.

Using the Ostwald process, ammonia is vaporised and then oxidised over a 95% platinum and 5% rhodium catalyst at 930 °C (1,710 °F) and 6.5 bar (650 kPa) to form nitric oxide and superheated steam.

The cooled reaction gases are then passed through the bottom of an absorption column where a stream of air is added to oxidise nitric oxide to nitrogen dioxide.

Ammonia is vaporised and then sparged through a proportionate amount of nitric acid to make an 83% wt/wt ammonium nitrate solution.

In 2010 Sable initiated the Clean Development Mechanism project in response to the ever growing concern over the environment, the first of its type in Zimbabwe.

Such projects can earn saleable certified emission reduction (CER) credits, each equivalent to one tonne of CO2, which can be counted towards meeting Kyoto targets.