Influência dos carbonatos de lítio, sódio e potássio (Li2CO3 Na2CO3, Na2CO3 e K2CO3) na reologia de argilas esmectíticas do estado da Paraíba para fluidos de perfuração base água e base orgânica.

Abstract

The sodium (Na+), lithium (Li+) and potassium (K+) cations are first in the plane of selectivity for obtaining monoctonic smectic clays from the polycationics, specifically influencing the rheological behavior of the drilling fluids. This work intends to verify the influence of lithium, sodium and potassium alkali carbonates (Li2CO3, Na2CO3 and K2CO3) on the rheology of smectic clays in the state of Paraíba for use in water based and organic base drilling fluids. First, the polycationic samples were characterizedphysically, chemically and mineralogically through X-ray diffraction, chemical composition through the classical method (volumetry, gravimetry and titulometry), granulometric analysis by laser diffraction, differential thermal and thermogravimetric analysis, determination of the exchange capacity Of cations and specific area. The polycationic samples were then transformed into monoctonic by additivation with the Li2CO3, Na2CO3 and K2CO3, again being characterized. After that, the study was divided in 2 (two) parts, in Part I a rheological study of the polycation and monoctonic samples for water based drilling fluids was performed, based on Petrobras EP-1EP00011-A, 2011 and API 13A, 1993, also evaluating the swelling of the dispersions and flow curves. The polycationic and monoctonic samples were organophilized and characterized by the analyzes mentioned above, with the exception of particle size analysis, cation exchange capacity and specific area. In part II, the compatibility oforganophilic samples with the organic diesel medium was studied to verify the suitability to form stable dispersions for organic base drilling fluids based on the Petrobras standard EP-1EP-00023-A, 2011; Swelling of the dispersions and flow curves was also evaluated. Results show that there was an improvement in the rheological properties (with the presence of thixotropy) of clay dispersions added with Li2CO3 and Na2CO3, in that order, and organophylls of Li2CO3 and Na2CO3, in that order, for use in water based and organic base drilling fluids respectively .