A method for controlling the grain size distribution in a decomposition containing an agglomeration stage row of a bayer process

摘要

The invention concerns a method for performing -ecomposition in an American type Bayer circuit whereby the quality of the particle size grading is monitored by measuring the screen undersize at X2 mu m of the flowing hydrate, comprising: a) a preparation step which consists in establishing a relationship R between the screen undersize at X1 mu m and the screen undersize at X2 mu m, wherein X1 is strictly less than X2 and deducing therefrom triggering levels on the screen undersize at X1 mu m; b) the performing proper of the process consists, besides the daily measurement of the screen undersize at X2 mu m, in daily measuring the screen undersize at X1 mu m of the flowing hydrate and triggering a corrective action on the suspension at the decomposition head when the value of the screen undersize measured at X1 mu m reaches one of the triggering levels established during the preliminary step and regularly updated.