Modified Bentonite As a Dissolve-Extrusion Composite and Its Modification Mechanism

Area of Science:

• Materials Science
• Geological Engineering
• Chemical Engineering

Background:

• Current geological core drilling fluids often lack performance and are difficult to maintain.
• Simple formulations typically do not meet the demands of complex geological formations.
• Powder surface modification is underutilized for bentonite in drilling fluid applications.

Purpose of the Study:

• To develop a novel, high-performance drilling fluid using surface-modified bentonite.
• To create a simple, low-cost, and easily maintainable drilling fluid system.
• To investigate the efficacy of ZJ-1 and ZJ-2 modifiers for bentonite.

Main Methods:

• Developed a dissolution and extrusion composite modification method for bentonite.
• Employed orthogonal design experiments to optimize modifier dosage, ratio, and preparation conditions.
• Analyzed modified bentonite performance via rheological properties, filtration loss, and microscopy (FTIR, XRD, SEM).

Main Results:

• Optimal conditions: 2% total modifier dosage (ZJ-1:ZJ-2 ratio of 1.5:0.5), 10h reaction time, 100°C, 0.5 MPa.
• Modified bentonite drilling fluid showed significantly improved performance over regular bentonite.
• Achieved filtration loss of 7.5 mL, funnel viscosity of 51.5 s, and enhanced rheological properties.

Conclusions:

• Surface modification of bentonite with ZJ-1 and ZJ-2 yields a versatile additive for drilling fluids.
• The new formulation (water + modified bentonite) offers superior performance and ease of use.
• This advancement provides a practical solution for the geological core drilling industry.