Lignosulfonate could retard the setting of cement. It is designed for use in wells with circulating temperatures between 125°F (52°C) and 206°F (97°C) – 290°F static (143°C) ,is compatible with the following:
- Fresh or saltwater slurries
- Most cement additives
- All API cements
- Bentonite cement
- Pozmix® A cement
Benefits as follows
- Increased concentrations of HR-5 additive enhance the predictability of cement thickening times.
- Decreases the danger of over-retarded slurries at the top of a long cement column.
- Provides early cement strength development.
- Helps displace slurries at high rates while maintaining formation pressure.
The modified grade represents lignosulfonates that have been blended or reacted with a second component. The compounds most commonly used as blend components are boric acid and the hydroxycarboxylic acids, or their salts. Blended materials are available as calcium or sodium salts. The modified lignosulfonates are typically used at a BHCT of 200°F or above. They are more effective than the purified grade at temperatures greater than 250°F. The advantages, whether a blend or reacted product, are their improved high-temperature stability above 300°F BHCT, increased dispersing activity, and synergism with fluid-loss additives.