Eventos Anais de eventos
COBEM 2017
24th ABCM International Congress of Mechanical Engineering
Study of the relationship between the mineralogical composition and the disintegration of shales from Paraíba and Ceará states of Brazil
Submission Author:
Matheus Nikolaos Carneiro Brunet , PB
Co-Authors:
Caline Leal, Matheus Nikolaos Carneiro Brunet, Luciana Amorim, Francisco Cézar Costa Nogueira, Waleska Rodrigues Pontes da Costa, Hélio Lira
Presenter: Caline Leal
doi://10.26678/ABCM.COBEM2017.COB17-2776
Abstract
The problem of instability of wells in shale formations has been a major concern for oil engineers since the beginning of oil well drilling. Shales present an instability behavior when drilled with aqueous fluids, which is often associated to their mineralogical composition; shales that have a higher amount of hydratable clay minerals tend to be unstable in the presence of water. In view of this, this work has as objective to relate the mineralogical composition of the shales with their disintegration. In order to do so, five samples of shales from the Rio do Peixe Basin, located in the State of Paraíba, were characterized. These samples were named as S1, S2, S3, S4 and S5. For comparison purposes, a clay sample of industrialized Bentonite Sodium, named as BS, was also characterized. The characterization was performed by methods of cation exchange capacity (CEC), particle size analysis by laser diffraction and X-ray diffraction (XRD). In addition, studies of disintegration, in the presence of deionized water, aqueous solution of potassium citrate (salt employed as a swell inhibitor of aqueous drilling fluids), and drilling fluid, were performed following API (American Petroleum Institute) standards. The results suggest that the phenomenon of disintegration is manifested in the presence or absence of reactive clay minerals. Moreover, the results obtained showed that the disintegration behavior does not present direct relation to the content of clay fraction. And, finally, it can be concluded that, the samples of shales studied showed considerable disintegration when in the presence of deionized water. However, this disintegration is widely reduced in the presence of potassium citrate salt or aqueous drilling fluids inhibited with the potassium citrate salt.
Keywords
Shale, Disintegration, instability, characterization
