Análise estatística dos parâmetros de um moinho classificador de impacto na determinação de granulometria de tinta em pó

Abstract

The search of powder coatings in the global market has been growing, generating a need on the part of manufacturers to improve paint production technologies, in order to guarantee the consumer a better quality in the products and greater market competitiveness. The manufacturing process of a conventional powder coating involves, in short, three steps – the pre-mixing of raw materials, extrusion and micronization. The micronization phase guarantees the powdery appearance of the coating, with granulometry being one of the key parameters for good application and appearance of the coating. The present work aims to explore the influence of different parameters of an impact classifier mill (ICM) on the particle size of the powder coating. Using statistical methods such as OFAT, ANOVA and DOE, it was concluded that the parameters of sieve opening, classifier rotation, grinding disc rotation and fluidizer dosage are the most critical in determining the d50 (diameter of the particle that half of the sample is finer) of the product. An equation correlating the critical parameters and the d50 was proposed, limited to the configuration of the milling system and product tested in the experiments. This equation was later validated on another date, confirming the robustness of the coefficients obtained.