Abstract
The acrylic paint can be contaminated by bacteria (and rarely fungi), due to the presence of microbiological residuals on the container, that are responsible for the degradation of the paint chemical and physical characteristics. Hence, as stated by the EU regulation of May 2015, it is mandatory to provide an in-can preservation of the paint. When subject to different temperatures, the in-can product could evaporate and then condense under the cover of the can. Since biocides are not volatile substances, they are present in very small quantities in the cover phase setting the bacteria free to proliferate. This research group is working on the modelling of the microbiological evolution of in-can systems with the aim of predicting the contamination extent and of obtaining proper design procedures to guarantee the protection (of both the can and the cover phase). The thermofluid-dynamic model implemented on gPROMS software is validated through the comparison with literature experimental data. In this paper we present the criteria at the basis of the cited system modelling. More in detail, this work reports the thermodynamic (phase equilibria using NRTL model) and the kinetic fundamentals, the estimation of the kinetic parameters through a literature comparison and a case study (considering MIT biocide) considered for the model validation.
