Slide Background
Slide Background

THE BIOLOGICAL DEGRADATION OF SODIUM OXALATE IN AN ALKALINE ENVIRONMENT

Morton, R.A.

The biological degradation of sodium oxalate in the near neutral pH range is a natural phenomena which has limited application in the alumina industry. However, a biological oxalate degradation process which operates in alkaline environments is now available. By being able to degrade an oxalate/caustic stream to a carbonate/bicarbonate solution the need for any pre-treatment or neutralisation of the oxalate prior to processing is eliminated. This process can be integrated into existing sodium oxalate removal systems to increase the efficiency of oxalate removal. By operating at lower levels of sodium oxalate in plant liquors, along with the optimal dosing of reagents to reduce fines and increase particle strength, improvements in alumina quality can be achieved. The details of the application of this alkalophilic microorganism to sodium oxalate destruction along with the subsequent recovery of soda are described.