THE EFFECT OF ALUMINIUM OXIDE NANOPARTICLES ON THE RHEOLOGICAL PROPERTIES OF WATER BASED DRILLING MUD

ABSTRACT
The success of well-drilling operations is heavily dependent on the drilling fluid. Drilling fluids cool down and lubricate the drill bit, remove cuttings, prevent formation damage, suspend cuttings and also cake off the permeable formation, thus retarding the passage of fluid into the formation.
During the drilling through induced and natural fractures, huge drilling fluid losses lead to the higher operational expenses. That is why, it is vital to design the drilling fluid, so that it may minimize the mud invasion in to formation and prevent lost circulation. Typical micro or macro sized lost circulation materials (LCM) show limited success, especially in formations dominated by micro and Nano-pores, due to their relatively large sizes. The objective of this project was to investigate the performance improvement by the usage of Aluminium Oxide NPs (nanoparticles).
The laboratory measurements included measuring the filtrate losses using the standard API LTLP (Low temperature, Low pressure) filter test and also some rheological properties of the mud such as the mud density and pH with their respective apparatus. This project reports an experimental study on filtration properties of water-based Nano and Local additive drilling fluids under static conditions. The lowest filtrate loss value of 14.4ml occurred for an addition of 1.0g of aluminium oxide Nano-particles acting alone as the LCM. Under API standard filtration test at LTLP, more than 70% reduction in fluid loss was achieved in the presence of 0.5-2.0 wt% NPs. The results have also shown that the filter cake developed during the Nano and Local Additive based drilling fluid filtration was thin, which implies high potential for reducing the differential pressure sticking problem, formation damage and torque and drag problems while drilling. NP-based drilling fluid
with specific characteristics is thus expected to play a promising role in solving the circulation loss and other technical challenges faced with commercial drilling fluid during oil and gas drilling operation.