Identification of the model and controlling step in acid liquor neutralization process at the nickel processing industry

Abstract

The objective of the investigation was to estimate the mathematical model parameters for fluid-solid non-catalytic systems in order to describe the behavior of a sequence of continual reactors with agitation and installation in series based on the peculiarities of the existing system in the Neutralization Plant at the nickel plant site “Comandante Pedro Soto Alba” of Moa. The work included the calculation of complete reaction times for particles having invariable and decreasing sizes considering the model of center without reaction. The potential controlling steps were: external diffusion in liquid films, diffusion through product build up layers, chemical reaction in particles with invariable sizes and external diffusion in liquid films of particles with decreasing sizes. When analyzing the results, it was possible to rule out chemical reaction and diffusion in the scab as controlling steps. It was concluded that the step with higher probability of controlling the neutralization process is external diffusion.