Use cases and specific amounts of nanocellulose as additives in oil well drilling fluids

There are some research and practical cases of the application of nanocellulose as an additive in oil well drilling fluids. Its main function is to improve the rheological performance of drilling fluids, reduce filtration loss, enhance well wall stability and improve drilling efficiency. The specific amount of addition and use effect will vary depending on the drilling conditions, type of drilling fluid (such as water-based or oil-based drilling fluid) and the modification type of nanocellulose. Here are some common use cases and volume information:

1. Improve the rheological performance of drilling fluid

Nanocellulose can increase the viscosity and thixotropy of the drilling fluid, making it easier to carry drill cuttings and improve the shear thinning characteristics of the drilling fluid. The addition amount is usually between 0.1% and 1.5% (mass fraction)**, and the rheological parameters of the drilling fluid are adjusted as needed.

• Case : Studies have shown that when using unmodified cellulose nanofibers (CNF) as additives for water-based drilling fluid, adding 0.5%** can significantly improve the viscosity and thixotropy of the drilling fluid, so that the drilling fluid can be carried out. The chip ability is greatly enhanced.

2. Reduce filtration loss

Nanocellulose , especially modified (such as TEMPO oxidation or carboxylation), can form an efficient filtration control layer to reduce filtration loss of drilling fluid. The addition of nanocellulose can increase the density and integrity of the mud cake, thereby reducing the filtration loss.

• Case : Adding **0.3% to 1.0%** TEMPO oxidized cellulose nanofibers to oil-based drilling fluid can significantly reduce filtration loss and improve the stability of the well wall.

3. Stability and lubricity of well walls

Nanocellulose can enhance the lubricity of the drilling fluid, reduce the friction between the drill bit and the drill rod, thereby reducing the risk of drilling during drilling. In addition, its high specific surface area and fibrous structure help improve the stability of the well wall and prevent collapse.

• Case : Adding 0.5% to 1.0% carboxylated cellulose nanofibers to the drilling fluid improves the mechanical stability of the well wall and enhances the lubricating performance of the drilling fluid.

4. Temperature stability

Nanocellulose can still maintain good stability under high temperature conditions, so it is suitable for drilling fluid applications in deep wells and high temperature environments.

Summarize

Typical additions of nanocellulose in oil well drilling fluid range from 0.1% to 1.5% (mass fraction), depending on the type of drilling fluid and the required performance adjustment.