Schlumberger has announced the release of EverCRETE CO2-resistant cement. 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.
"The development of EverCRETE cement is one of many innovations undertaken by Schlumberger in support of the Company's new Carbon Services initiatives," said Patrick Schorn, President of Well Services for Schlumberger. "To be effective, storage wells must be able to maintain stable, leak-free conditions for hundreds of years," he added.
Extensive lab-testing of EverCRETE cement was performed under diphasic conditions (wet supercritical CO2 and CO2 water saturated) up to 110 degrees C (230 degrees F) and 280 Bar (4,061 psig). These tests positively demonstrated no signs of degradation.
Schlumberger formed its Carbon Services group with the goal of researching and implementing the use of appropriate sites, technologies and techniques to provide comprehensive CO2 geological storage solutions. EverCRETE cement is a key enabling technology in this endeavor.