Carboxymethyl Cellulose (CMC) is a fluid loss agent commonly used in drilling fluids. As an important chemical additive, CMC’s main role in drilling fluids is to control fluid loss, improve the performance of drilling fluids, protect well walls, and maintain the stability and safety of drilling.

1. Control filter loss
Fluid loss refers to the amount of drilling fluid percolating into the formation. Excessive fluid loss can lead to formation pressure imbalance, which can lead to well wall collapse and other problems. As a fluid loss reducer, CMC forms a viscous protective layer in the drilling fluid, which effectively reduces the amount of water in the drilling fluid penetrating into the formation, thus controlling the fluid loss. This protective layer can form a dense filter cake on the surface of the formation to prevent water in the drilling fluid from penetrating into the formation.

2. Increase the viscosity of drilling fluid
CMC can significantly increase the viscosity of drilling fluid and enhance its ability to carry cuttings and suspended solid particles. This is essential to remove debris from the bottom of the well and keep the wellbore clean. Proper viscosity can also effectively prevent wellbore collapse and ensure smooth drilling operations.

3. Protect the well wall
During the drilling process, the stability of the well wall is very important. CMC effectively protects the well wall by forming a protective film on the well wall surface to reduce the erosion and erosion of the well wall by drilling fluid. This helps avoid accidents such as well wall collapse and lost circulation, and ensures the safety and continuity of drilling operations.

4. Improve the rheology of drilling fluid
CMC has good water solubility and rheological properties, which can adjust the rheology of drilling fluid so that it can maintain stable performance under high temperature and high pressure conditions. Good rheology is not only beneficial to the circulation of drilling fluid and the carrying of cuttings, but also prevents the drilling fluid from stratification and condensation in high-temperature and high-pressure environments.

5. Adapt to different drilling environments
As a chemically stable polymer compound, CMC can adapt to different types of drilling environments. Whether it is fresh water, salt water, or polymer drilling fluid, CMC can exert a good filter loss reduction effect. This makes CMC a very versatile drilling fluid additive and is widely used in all types of drilling operations.

6. Environmental protection
CMC is a natural cellulose derivative with good biodegradability and environmental protection. Compared with some synthetic chemical fluid loss agents, CMC causes less environmental pollution and is more in line with the environmental protection requirements of modern drilling operations.

7. Economical
The production cost of CMC is relatively low, the use effect is significant, and the cost performance is high. Therefore, CMC is an economical and practical choice among drilling fluid additives and is widely favored by the oil drilling industry.

Carboxymethyl cellulose (CMC) is used as a fluid loss reducer in drilling fluids to control fluid loss, increase drilling fluid viscosity, protect well walls, improve drilling fluid rheology, adapt to different drilling environments, and is environmentally friendly and economical. plays an important role. Its superior performance makes it an important member of drilling fluid additives, providing a strong guarantee for the smooth progress of drilling operations and the stability of the well wall.