PRECIPITATION FROM NICKEL SULPHIDES LIQUOR SETTLER EFFLUENT CARBONATO IN THE COMPANY ERNESTO CHE GUEVARA

Abstract

The need to identify the factors most influence on the precipitation of nickel sulfide, clarified liquor from the clarifier effluent existing nickel carbonate in the calcination and sinter plant of the Company Commander Ernesto Guevara. Moa, is the subject of work, which is performed at bench scale using sodium hydrogensulfide as precipitating agent. The study was continued from the thermodynamic point of view through a full factorial experimental design at two levels, we evaluated the influence of temperature, stirring speed and precipitating reagent consumption on the process. Mathematical statistical models for times of 40, 80, and 120 seconds, shows that the most influential independent variables in the precipitation of nickel sulfide, are stirring speed and the volumetric ratio of liquor / precipitating agent. Another outcome is the establishment of the physical transformations-chemicals that lead to precipitation of nickel sulfide (II), showing values above 98 % efficiency for a low dosage of reagent, and thermodynamic models based on temperature, where Ke depends on the nature of the species
precipitated From the standpoint of environmental partner is able to diminish the negative impact on the ecosystem and demonstrate the feasibility of application of the models obtained on an industrial scale, according to preliminary economic calculations made.