HOUSTON -- Schlumberger has released EverCRETE CO2-resistant cement. According to the company, this new product is specifically engineered to ensure long-term zonal isolation in wells with high concentrations of carbon dioxide in either wet or gaseous states.
The cement system is highly resistant to CO2 attack under wet supercritical CO2 and CO2 -saturated water conditions. These conditions, typically encountered in carbon geological storage projects or CO2 injection well applications, cause rapid degradation of standard oilfield cements.
EverCRETE cement can be prepared in a standard bulk plant and its density can be tailored to most well requirements. The new system can be pumped as a tail-slurry across the CO2 injection zone or used as a lead-slurry to protect the casing string from CO2 attack in front of any reservoir with CO2 content, all using standard equipment.
Extensive lab-testing of EverCRETE cement was performed under diphasic conditions (wet supercritical CO2 and CO2 water saturated) up to 110°C (230°F) and 280 Bar (4,061 psig). These tests positively demonstrated no signs of degradation.