67
Composite Leakage Plugging Agent: A Novel Solution for Lost Circulation Control
2023/4/28
Lost circulation is a common and challenging problem in drilling operations, especially in deep and ultra-deep wells. It refers to the situation where drilling fluid flows into the formation through fractures, pores, or other pathways, resulting in loss of drilling time, mud, and plugging materials. It may also cause serious accidents such as wellbore collapse, stuck pipe, blowout, etc. Therefore, developing effective and reliable lost circulation materials (LCMs) and plugging technologies is of great importance for drilling safety and efficiency.
Composite leakage plugging agent is a novel and effective solution for lost circulation control in drilling operations. It has a unique plugging mechanism that can form a multi-layered plugging zone that can adapt to different types of leakage pathways and downhole conditions. It has many advantages such as low viscosity, high temperature resistance, strong salinity resistance, low filtration loss, etc. It is suitable for various types of drilling fluids and can be used in different drilling scenarios. It is also a safe and eco-friendly product that can reduce the environmental impact of drilling operations.
What is Composite Leakage Plugging Agent?
Composite leakage plugging agent (CLPA) is a new type of LCM that combines the advantages of physical and chemical plugging mechanisms. It consists of different kinds of particles, fibers, gels, resins, and other components that can form a complex and stable plugging zone in the leakage pathways. CLPA can not only bridge and seal the large fractures and vugs, but also penetrate and fill the micro-fractures and pores. It can also react with the formation or the drilling fluid to form a solid or semi-solid gel that can withstand high pressure and temperature.How Does Composite Leakage Plugging Agent Work?
CLPA works by forming a multi-layered plugging zone that can adapt to different types of leakage pathways and downhole conditions. The plugging zone consists of four layers: the filter cake layer, the bridging layer, the filling layer, and the gel layer.- The filter cake layer is formed by the fine particles and fibers in the CLPA that are deposited on the wellbore wall by the filtration process of the drilling fluid. It can reduce the permeability of the wellbore wall and prevent further fluid loss.
- The bridging layer is formed by the coarse particles and fibers in the CLPA that are trapped in the large fractures and vugs by the bridging effect. It can block the main leakage channels and provide mechanical support for the plugging zone.
- The filling layer is formed by the small particles and fibers in the CLPA that are squeezed into the micro-fractures and pores by the differential pressure. It can fill the gaps between the bridging particles and fibers and enhance the sealing effect.
- The gel layer is formed by the gel-forming components in the CLPA that are activated by temperature, pH, or other triggers. It can bond with the formation or the drilling fluid to form a solid or semi-solid gel that can increase the strength and stability of the plugging zone.
What are the Benefits of Composite Leakage Plugging Agent?
CLPA has many benefits compared to conventional LCMs, such as:- It has a wide range of particle sizes and shapes that can match different types of leakage pathways.
- It has a low viscosity and frictional resistance that can reduce the pumping pressure and energy consumption.
- It has a high thermal stability and salinity resistance that can maintain its performance under harsh downhole conditions.
- It has a low toxicity and environmental impact that can reduce the environmental risk of drilling operations.
Composite leakage plugging agent is a novel and effective solution for lost circulation control in drilling operations. It has a unique plugging mechanism that can form a multi-layered plugging zone that can adapt to different types of leakage pathways and downhole conditions. It has many advantages such as low viscosity, high temperature resistance, strong salinity resistance, low filtration loss, etc. It is suitable for various types of drilling fluids and can be used in different drilling scenarios. It is also a safe and eco-friendly product that can reduce the environmental impact of drilling operations.
