Salt-Resistant High-Strength Cement Slurry Suitable for Large Hole Cementing in Salt Bed of Buzios Oilfield

This paper investigates cementing technology for large-diameter wells in the Buzios oilfield's salt crust layer, systematically analyzing core challenges such as low displacement efficiency, salt crust layer dissolution, and high-temperature CO2 corrosion. To address these issues, the research team developed displacement efficiency simulation software to optimize construction parameters and enhance cement slurry displacement performance precisely. An innovative high-strength cement slurry system resistant to salt was developed, using semi-saturated brine for slurry preparation to balance salt layer dissolution and performance stability. Special additives were introduced to enhance rheological properties and curing strength. Additionally, a new salt-resistant styrene-butadiene latex was applied to the cement slurry, forming a dense corrosion-resistant layer that effectively blocks the penetration of acidic gases and significantly improves the corrosion resistance of the cement stone. This technology comprehensively addresses the technical challenges associated with cementing large-diameter wells in salt gel layers, providing an effective solution to enhance cementing quality and long-term wellbore stability. It holds significant reference value for cementing projects in similar complex geological conditions.