Per: JOSE OCTAVIO DA SILVA SIERRA FERNANDEZ (greylogix brasil), Diogo Alves Massaneiro Guebert (universidade federal de santa catarina), luismar marques porto (UNIVERSIDADE FEDERAL DE SANTA CATARINA), agenor de noni jr. (universidade federal de santa catarina)
Abstract:
The acid pickling process generally consists of applying a strong acid (HCl) to a metal surface in order to remove layers of iron oxide (scale). Typically, turbulent pickling lines are used in order to maximize the productivity of industrial systems. This paper developed a phenomenological approach to model the kinetic behavior of scale consumption based on shrinking core model. Some geometric, chemical, and thermodynamic assumption are described and were made to simplify the model structure, exempla: chemical reaction being the limited step, respecting by a generic r_{HCl}=k\bullet C_{HCl}^m rate law equation. The validation was made based on experimental data and empirical models extracted from the literature. As a result, an equation to estimate the pickling time were developed. The results demonstrated, in comparison with empirical and sigmoidal models, a good consistency with literature, showing errors, under certain conditions, below 5%. This proposed approach can support future process optimization studies either in laboratorial or industrial scale. At the end, improvements in environmental impact reduction and cost savings could be explored, supported by using SCM