Drilling Industry Glossary

Methylene Blue (MBT Capacity)

Methylene blue (lb/bbl) is measured by MBT test to determine the concentration of reactive clays present in a water-base drilling fluid based on the amount of methylene blue dye absorbed by the sample. Commercial clays such as bentonite and formation solids such as shales adsorb methylene blue and contribute to the methylene blue capacity of the mud.