Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
The role of Pressure on the yield stress and dynamic moduli for an Inverted Emulsion Drilling Fluid
Submission Author:
GÉSSICA PALAORO , PR
Co-Authors:
GÉSSICA PALAORO, Jonathan Galdino, Diogo Elias da Vinha Andrade, Admilson Franco
Presenter: Diogo Elias da Vinha Andrade
doi://10.26678/ABCM.ENCIT2022.CIT22-0718
Abstract
Oil and gas exploration and production in deep and ultra-deep wells, located in high pressure and high-temperature zones (HP/HT), is increasing considerably to meet global energy demand. Exploration in HP/HT zones presents several challenges to the performance of drilling fluids for well control. The rheological characterization of drilling fluids has been extensively investigated through experiments at atmospheric pressure; however, there are many open questions under high-pressure conditions. The objective of this work is to perform a rheological characterization of invert emulsion drilling fluid with measurements performed under a wide pressure range. The sample is an inverted emulsion using an olefin base oil with an internal phase of sodium chloride brine, with a 60/40 oil to water ratio. Other drilling fluid components are primary and secondary emulsifiers, lime, organophilic clay, and barite. The measurements were performed on the Anton Paar MCR 502 controlled shear stress rotational rheometer coupled to a pressure cell system that allows applying pressures up to 1000 bar. The pressure supply unit consists of an upstream hand pump that pressurizes the internal oil with a pressure range of up to 700 bar, a spindle pump for applying pressures up to 1000 bar, and a separator unit responsible for transferring the pressure from the oil to the sample. The results show that the impact of the pressure is more relevant in the solid-like than in the liquid-like regime. The yield stress and the dynamic modulus tend to increase under pressure. We can anticipate that, interestingly, the higher the applied pressure, the greater the deformation that the fluid withstands in the solid-like regime. The authors are not aware of a similar discussion having been reported previously in the open literature. These findings bring essential information for the engineers in the oil and gas field since one of the main concerns at high-pressure conditions must be the drilling fluid behavior in the solid-like regime.
Keywords
inverted emulsion, drilling fluid, High pressure, Rheology, yield point
