EPA4 Process for extracting alumina
A process for extracting alumina from bauxite comprising the steps of concentratring a portion of spent caustic liquor (18), combining said concentrated spent caustic liquor with a bauxite slurry (3) to provide a final alumina to caustic ratio (A/C) of greater than in the slurry/liquor mixture, heating the mixture by means of a heat exchanger (5), subjecting the mixture to digestion in a