Application of Novel Saturated Salt Cementing Slurry System in Salt Formation

When drilling through salt formations, salt dissolution and creep frequently occur, posing significant technical challenges for cementing operations. To mitigate the adverse effects of salt dissolution on cement slurry performance, saturated saltwater can be used for slurry preparation. Three novel agents (salt-resistant fluid loss agent, salt-resistant dispersant, and accelerator) are employed and a novel saturated saltwater cement slurry system is constructed to address issues such as high fluid loss, thixotropy and thickening, prolonged thickening time, and slow development of compressive strength in saturated saltwater cement slurry. Evaluation results indicate that this system exhibits excellent rheology, fluid loss control, compressive strength, and free fluid. It also has an adjustable thickening time with smooth thickening time curve and no plateau phenomena. Compared to traditional salt cement slurry systems, the new system demonstrates superior salt resistance, stronger bonding performance, and better contamination resistance. This system was used in the 9-5/8"casing cementing in the salt paste layer section of Well A in the M Oilfield in Iraq. The on-site cementing operation was successful, and CBL testing showed a 95% cementing qualification rate.