The vibrofluidized bed developed in this work, consisting of a transparent plexiglass tube with an inner diameter of 0.1 m and a height of 0.5 m, was designed for the fluidization of adipic acid. The fluidization behavior of dry adipic acid with particle diameters in the range of 75 - 600 mm and a density of 1340kg/m³ was studied using mechanical vibration for different sample loads. Variables studied for the wet material include frequency and amplitude of vibration and moisture content of the particles. On the basis of the quantitative flow curve data and visual observations, it is concluded that the fluid dynamics of the bed with wet sticky particles, both vibrating and not vibrating, is different from that of the bed with dry particles.

In this work the quality of sulphur-coated urea was determined by the urea dissolution rate and analysed by electron microscopy. Particles of urea were coated in a two-dimensional spouted bed, having a 60° slanted base angle and an atomization nozzle installed at the base. Elementary sulphur was liquefied and atomized on the particles. The experiments were planned with the objective of verifying the influences of flowrates of sulphur and atomized air and the temperature of the air used in the spouted bed on the quality of the coated particle surface. The temperature of the spout air and the flowrate of the atomized air showed a significant influence on the quality of the coating.

The drying of annatto seeds (Bixa orellana L.), red piave cultivate, was studied in a fixed bed dryer. The best conditions were estimated to minimize the loss of coloring and to obtain final moisture of the seeds in appropriate levels to its conservation and maintenance of quality. The quantification of the influence of entrance variables in the final contents of bixin and moisture seeds and the identification of the optimal point was performed through the techniques of factorial design, response surfaces methodology, canonical analysis and desirability function. It was verified that the final moisture of the seeds may be estimated by a second-order polynomial model and that the final content of bixin is only significantly influenced by the time of drying being described properly by a linear model, for the seeds used in this study.