Improving Drilling Fluid Properties at High Pressure Conditions Using Selected Nanomaterials

[摘要] Drilling fluids with conventional lubricants (including solid and liquid lubricants) will produce lubricant film between drill string and wellbore/casing, but this film will not be strong enough to protect the bit bearing surfaces subjected to high load conditions during the drilling operations, resulting in shortening the life of drill bit. In this research, the possibility of using nanomaterials as extreme pressure lubricants was investigated by adding different concentrations (0.02, 0.05 and 0.1) wt. %of TiO2nanoparticles (NPs) and Cu NP into water- based mud. The lubricating film strength of water based mud samples under extreme pressure conditions were measured using Extreme Pressure (EP) and Lubricity Tester. With the purpose of getting the best performance from extreme pressure lubricants, the effect of nanomaterials on rheological (including plastic viscosity, yield point, apparent viscosity, and gel strength) and filtration (including filtrate loss volume and mud cake thickness) properties were measured. TiO2 NPs and Cu NP showed a good enhancement in lubricating film strength under extreme pressure conditions. The maximum value of lubricating film strength increasing percentage (69.6%) was obtained using TiO2 NPs with concentration of 0.1wt.%.

[发布机构] Petroleum Department, College of Engineer, University of Baghdad, Baghdad, Iraq^1;Petroleum Technology Department, University of Technology, Baghdad, Iraq^2

[关键词] Apparent viscosity;Drilling fluid property;Drilling operation;Extreme pressure conditions;High-pressure condition;Liquid lubricants;Lubricating films;Mud cake thickness