Evaluation of Nanofibrillated Cellulose as Rheology Modifier of Water Based Drillings Fluids (WBMs) for Argentina Shale

NATALIA CASIS; DIANA ALEJANDRA ESTENOZ; ELEONORA ERDMANN; YURANY ANDREA VILLADA VILLADA; MARÍA SOLEDAD PERESÍN

Barcelona

Congreso; 10th World Congress of Chemical Engineering (WCCE); 2017

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 with the 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. A shear-thinning behavior with notable effect on the concentration of CNF was observed. Also, mud rheological properties very close to the base mud were achieved for composition of PAC = 8.00 g/L and CNF = 3.00 g/L. Structural changes were assessed from scanning electron microscopy (SEM) and particles agglomeration and a film formation due to the presence of polymers were observed. Additionally, mud filtration essays indicated that the CNF is a good filtration control agent. The Sisko model and statistical analysis were used to determine rheological parameters.