Análise microscópica e avaliação quantitativa do processo de desestabilização de emulsões água-em-óleo com aplicação de campo elétrico

Abstract

This work analyzes the stability of water-in-oil emulsions with the application of electric field, which is a technique of ample practical use, but still with little understanding on how to define the maximum applicable electric field or the optimal electric field to maximize the separation of the water from the oil. The current drained by the emulsion is the only variable monitored in the works present in the literature and, in order to increase the understanding of the destabilization process, the visual monitoring of the process was done using a microscope. By microscopic analysis in conjunction with the measured current, the stability of the emulsions, as a function of the applied electric field, was evaluated. In addition, it was proposed the use of the Wavelet Transform, which allowed for a more precise identification of the electric field that generates phenomena such as flocculation, formation of an aqueous bridge between the electrodes (critical electric field) and breakup electric field. Model emulsions with water contents between 15 wt.% and 25 wt.% were used. Based on experimental fractional experimental design, the influence of parameters such as ramp time, electric field frequency, waveform and water content in the emulsion in the destabilization process was evaluated. It was identified that the most relevant variables in the destabilization process were the wave form and the water content, which is valuable for the operational practice.