Remoção de frações de óleo leve e pesado de rocha calcária através de sistemas microemulsionados

摘要

In this research the removal of light and heavy oil from disintegrated limestone wasinvestigated with use of microemulsions. These chemical systems were composed by surfactant,cosurfactant, oil phase and aqueous phase. In the studied systems, three points in the water -richmicroemulsion region of the phase diagrams were used in oil removal experiments. Thesemicroemulsion systems were characterized to evaluate the influence of particle size, surfacetension, density and viscosity in micellar stability and to understand how the physical propertiescan influence the oil recovery process. The limestone rock sample was characterized bythermogravimetry, BET area, scanning electron microscopy and X-ray fluorescence. Afterpreparation, the rock was placed in contact with light and heavy oil solutions to allow oiladsorption. The removal tests were performed to evaluate the influence of contact time (1 minute,30 minutes, 60 minutes and 120 minutes), the concentration of active matter (20, 30 and 40 %),different cosurfactants and different oil phases. For the heavy oil, the best result was on SME 1,with 20 % of active matter, 1 minute of contact time, with efficiency of 93,33 %. For the light oil,also the SME 1, with 20 % of active matter, 120 minutes of contact time, with 62,38 % ofefficiency. From the obtained results, it was possible to conclude that microemulsions can beconsidered as efficient chemical systems for oil removal from limestone formations