Description
Due to their higher pore pressures, formations above and below these producing zones need to be stabilized by fluids with higher density. However, an exposure of a depleted zone to the required high-density fluid can cause a significant loss of the whole fluid and differential sticking. Furthermore, uncontrollable drilling fluid losses are at times unavoidable in the large fractures of these formations. So it is difficult to drill such zones economically and safely by means of conventional rig equipment. Underbalanced drilling may be an alternative, but the extra time and equipment can greatly increase the cost of the operation. Recently, a new drilling fluid technology has been developed in an attempt to eliminate just these discussed problems. This novel technology is based on Aphron uniquely structured micro-bubbles of air. The air used to generate Aphron is usually incorporated into the fluid with conventional fluid-mixing equipment at ambient pressure, thereby reducing costs and safety concerns associated with conventional air and foam drilling operations. In this project, it is presented the design and properties of Aphron drilling fluids, and discuss how the fluid characteristics work together to provide superior performance in drilling operations that have a high risk of lost circulation.
Application
Drilling low-pressure/low-fracture-gradient sections
Drilling fractured and highly permeable sections
Reservoir drill-in applications
Drilling normal and low-pressure sections (high-density applications)
Achievements
Designing of Aphron -based drilling fluid formulations containing surfactants, polymers and nano-additives
Reducing mud loss circulation into the formation in low-pressure reservoirs
Improving the Aphron -based drilling fluid stability by using the nano-additives
Reduce the possibility of damage to the formation and simultaneous removal of H2S in the well using this type of fluid
Special product
NANO-Enhanced Aphron based Drilling Fluid RIPI’s N-EADF