Superior rheological properties, non-damaging nature of such drilling fluids are often desired factors along with the capability of drilling at the narrow mud-window margins. During deepwater drilling, fluid goes through a hot and temperature cycles for example: 70F (ambient temperature) to 40F (Sea Floor temperature) to 350F (reservoir temperature). For either diesel- or synthetic oil-based muds to be able to provide Flat-enough rheological properties during such hot and cold thermal cycles we have studied their rheological behavior at simulated drilling conditions. Understanding static gel strength development through the entire thermal cycle is key to understanding the resiliency of the fluid. A novel molecule has been synthesized in our laboratory that acts as a superior rheological modifier for next generation invert emulsion fluids at density ranges from 10-18ppg and temperature range of 40-450F. Smother drilling operation, higher rate of penetration (ROP), lower and steady equivalent circulating density (ECD), superior hole cleaning are demanding properties of an efficient non aqueous optimized drilling fluids for drilling deepwater reservoir sections. Drilling fluids are designed at 75, 100 and 125pcf density range both with diesel and synthetic base oil. Results demonstrated superior thermal stability during the thermal cycle of 70-40-450F with tight fluid loss control and ultrathin filter cake. Viscoelastic properties like storage (G’) and loss modulus (G”) of the fluids that influence the particulate suspension greatly are studied at the simulated thermal cycle. Gel strength values at 10sec, 10min and 30 min using Fann 35 apparatus are correlated with viscosity values obtained at extremely low shear rate (&lt;0.5 sec-1). Very interestingly, fluids optimized in this work have exhibited excellent flat-rheological behavior for a wide range of temperature. We will present a comparative analysis of relationship between what is currently used in the industry versus those developed in this work. The novel rheological modifier developed in this work enabled us designing extremely flat-rheology non aqueous fluids for deepwater drilling. Current work lead to development of a novel rheology modifier which can provide industry’s next generation high performance invert emulsion drilling fluids with flat-rheological behavior.

Rheological modifier for invert emulsion drilling fluids with flat-rheological behavior

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.