To produce soda ash, Penrice employs the complex ammonia soda or Solvay method, developed by Belgian chemist Ernest Solvay in the 1860s. A mixture of coke and the marble from Angaston is burnt in vertical shaft kilns to form carbon dioxide and quicklime. The carbon dioxide is added to a solution of ammonia and purified brine from Dry Creek to form a magma of crude sodium bicarbonate. Using steam from the Osborne Cogeneration Plant the sodium bicarbonate is decomposed to sodium carbonate in rotary dryers, producing a 'light ash'. Water is added to form new crystals of sodium carbonate monohydrate, which are dried to form 'dense soda ash' with a bulk density twice that of 'light ash'.
Process technicians at the main operator consoles .
The plant uses a state of the art fully integrated process control system. The process Technicians can monitor and operate the complete plant from a series of centralised computer consoles. Once processed, bulk soda ash is transported around Australia and overseas by road, rail and sea. The 48,000 t of sodium bicarbonate produced at the plant each year is used in a range of products, including stock feed, pharmaceuticals, bleaching of powders, biscuit and cake mixers and baking powder.