Measuring the pH During the Distillation Product of the Process Liquor ed. Part (III).

Abstract

The importance of pH mensuration during product liquor distillation coming from ammonium carbonates leaching of nickel was studied. The evaluation was carried out in a column of industrial distillation, operated by means of Supervisory Control and Data Acquisition EROS. The range of fed  liquor  was 25 m3/h and of temperature at the top, 10ºC. The ammonia concentration was variable, as well as dioxide of carbon, sulfur and nickel of the fed liquor. The concentration of
ammonia possesses a potential dependence of the pH in the unload of  the column and the nickel, polynomial of second order. The pH of the discharge pulp was determined for which  the cost is minimum as for consumption of reagent of nickel precipitation and losses of ammonia, recommending a range among 8,10 d≤  pH d≤  8,30 with a minimum loss of 0,111 C.U.C./(m3/h) and a saving of 0,674C.U.C./(m3/h). An increase of  the concentration of sulphur in the fed liquor, increases the dissolution of the nickel and of  the expenses of operation. An equation was obtained to predict of the  nickel concentration in the effluent of the distillation in dependence of  sulfur concentration in the fed liquor and the pH in the discharge of  the column.