CONICET | Buscador de Institutos y Recursos Humanos

Drilling fluids play an important role in oil and gas drilling operations, such as cleaning of well, suspending and carrying out cuttings, reducing friction between formation and drilling tools, stabilizing the well, cooling and lubricating tools, promoting hydraulic power, and being compatible with logging tools. Successful drilling operations are highly dependent on the selection of the fluids with desirable properties, which are mainly determined by their rheological and fluid filtration properties [1]. Depending of the composition, fluids are classified in three groups, water-based muds fluids (WBMs), oil-based muds (OBMs), and synthetic base muds (SDF). The WBMs contain additives that act as rheological modifiers and controllers of the loss of fluid to the formation. Currently, natural and synthetic polymers, such as guar gum, xanthan gum (XGD), polyanionic cellulose (PAC), polyacrylamide, polyacrylates, among others, have been used as rheological modifiers in WBMs.The use of nanoparticles of natural origin as rheological modifiers is an area of great interest due to its low cost and biodegradability characteristic. In this sense, the use of nanofibrillated cellulose (CNF) is a promising alternative. CNF can be obtained from different resources, such as wood, plants, marine animals, algae and bacteria, following different methods of preparation, for example enzymatic hydrolysis, mechanical disintegration, or oxidation.In this work the use of CNF as replacement of XGD in WBMs for Argentina?s shale is studied. The effect of the CNF composition on the rheological behavior and filtering properties is analyzed. The rheometric characterization of the fluids is complemented withthe structural analysis of fluids and the assessment of filtering characteristics. Sisko model and statistical analysis are employed to theoretically describe the rheological behavior of the fluids as a function of the polymer composition.