When used in oil and gas operations, bentonite typically needs to meet specifications outlined by the API (American Petroleum Institute) standard 13A, which includes parameters like a minimum viscometer dial reading of 30 at 600 revolutions per minute, a maximum moisture content of 10%, and a maximum filtrate volume of 15 milliliters, ensuring its ability to thicken drilling mud while maintaining acceptable filtration properties; key aspects include high swelling capacity, low sand content, and a suitable particle size distribution.
Key Bentonite Specifications for Oil and Gas:
- Moisture Content: Maximum of 10%
- Viscometer Dial Reading (at 600 rpm): Minimum of 30
- Filtrate Volume: Maximum of 15 ml
- Yield Point/Plastic Viscosity Ratio: Maximum of 3
- Particle Size Distribution: Primarily fine particles with a suitable range depending on application
- Cation Exchange Capacity (CEC): High value for optimal swelling properties
Important Considerations:
- Sodium Bentonite: Most commonly used due to its high swelling potential.
- Quality Testing: Regular testing to ensure consistency in properties like viscosity, filtration loss, and pH
- Application Specific Requirements: Depending on the drilling environment, specific adjustments to bentonite properties may be needed
