Contribuição ao estudo dos mecanismos envolvidos na aglomeração esférica de sólidos em suspensão

Abstract

This work was developed with the objective of to improve the state of the technique of spherical agglomeration of solids in suspension and to promote a progress in the necessary knowledge for its exploration in larger scale. We studied the agglomeration of salicylic acid crystals obtained from the reaction of sodium salicylate and sulfuric acid. The agglomeration was promoted using chloroform as bridging liquid, that was introduced in the solution immediately after the precipitation of crystals, the agglomeration being monitored by measurement of the suspension turbidity. The effect of variables as temperature, flow rate of chloroform feed, agitation and solid concentration on the following product properties were investigated: granulometric distribution, flowability, real and apparent densities, mechanical resistance, residual solvent, porosity and morphology. The results of this study allowed the identification of a new mechanism of agglomeration of solids from suspension and the possibility of controlling the process, in order to provide particles of a great variety of sizes, depending on the average size of the original crystals and according to the requirements of the final product application.