Avaliação de aditivo inibidor de precipitação de parafina na produção de petróleo

Abstract

Oil production has serious operational difficulties, where stands out the possibility of obstruction of the flow lines or production lines. The appearance of organic deposits on the inner walls of pipe is governed by three main events: paraffin precipitation, the precipitate diffusion of the liquid phase of oil to the pipe wall and wax deposition. The precipitation of paraffin depends on the composition and conditions of temperature and pressure along of flowing. This study sought to understand, through an extensive literature review, the origin and composition of the oil, the organic deposition mechanism and the most used mathematical models of predictability and crystallization kinetics, besides the forms of agents’s actions who act as surfactants. The aim of this study is to evaluate the kinetic behavior of paraffin’s precipitation in the presence of surfactant selected from comparative analysis of the paraffinic oil’s composition with and without a history of wax deposition. To this end, two samples of paraffinic oil were selected, with and without a history of wax deposition, from SergipeAlagoas basin, and were performed the following studies: identification of natural substance with potential surfactant in the composition of paraffinic oil with no history of wax deposition, selection of use of substances of mineral and vegetal's origin with potential surfactant; study of the kinetics of crystallization; study of rheological behavior of paraffinic oil; determination of wax appearence temperature (WAT); and morphological characterization by X-ray difratometry (DRX) of paraffinic oil before and after the addition of natural surfactant; The results showed that the substances identified as natural surfactants present in the oil without wax deposition had not effectiveness in inhibiting wax deposition nor facilitates the flow of paraffinic oil, and substances of mineral and vegetal origin had not effectiveness in inhibiting wax deposition too, but showed a significant shift to facilitate the flow of paraffinic oil at surface and wellhead's temperatures, what can be due the solvation of the solid fraction present in the sample. Therefore, the addiction of these substances at paraffinic oil of Sergipe-Alagoas Basis can reduce the problems of flowlines's obstructions and facilitate the flowing of oil.