TANNATHIN Thinner and Fluid Loss Control Ground Lignite | SLB


Thinner and fluid loss control ground lignite

Schlumberger Oilfield Services

TANNATHIN lignite is a naturally occurring material that reduces fluid loss and deflocculates water-based drilling fluids. A partially soluble additive, it provides thin, low-permeability filtercakes. It is an excellent emulsifier for oil-in-water emulsions and secondary deflocculant as well as is especially effective in high-temperature applications. It performs exceptionally well in dispersed systems as a synergistic additive with lignosulfonates.

Typical Physical Properties  
Physical appearance Black powder
Specific gravity 1.6–1.8
pH (1% solution) 4–5
Bulk density 52 lbm/ft3 [833 kg/m3]
Typical grind 90%–95% <20 mesh


TANNATHIN lignite is especially effective at stabilizing the properties of muds exposed to high temperatures and contaminants such as CO2 and calcium. TANNATHIN lignite is especially effective when treating cement contamination. It reduces the high viscosity and pH of cement-contaminated muds and reacts with calcium to lessen the contaminating effects.

Normal treatments of TANNATHIN lignite range from 1 to 8 lbm/bbl [2.85 to 22.8 kg/m3]. Due to their low pH, TANNATHIN lignite treatments require additional caustic soda or an alternative alkaline material to maintain a consistent pH. A normal ratio is one sack of caustic soda for every four sacks of TANNATHIN lignite. In high-salinity systems, it is preferable to premix the TANNATHIN lignite in medium-pH freshwater to enhance dispersibility, then add the premix to the active system. It is most effective in mud systems with a pH in the range of 9 to 11.


  • Provides improved filtration control
  • Reduces viscosity and gel strengths
  • Significantly extends the temperature stability of water-based fluids
  • Resists the effects of contamination
  • Improves filtercake quality by reducing its thickness and permeability
  • Reduces wall-sticking tendencies
  • Stabilizes rheological properties
  • Compatible with a wide range of water-based systems
  • Especially effective when treating cement contamination


  • Less effective at pH levels below 9.5

Toxicity and handling

Bioassay information is available upon request. Handle as an industrial chemical, wearing protective equipment and observing the precautions described in the safety data sheet.

Packaging and storage

TANNATHIN lignite is packaged in 50-lbm [22.7-kg] multiwall paper sacks. Store in a dry, well-ventilated area. Keep container closed. Store away from incompatibles. Follow safe warehousing practices regarding palletizing, banding, shrink-wrapping, and stacking.