New Slurry Design Concepts Using Multifunctional Additives to Improve Quality and Sustainability of Cementing Systems for Zonal Isolation

Abstract

The benefits of a new class of a multifunctional cement additive and the performance of the resulting cementing systems are evaluated in comparison to conventional slurry designs used for cementing wells in the Northeastern U.S. Cement testing procedures, lab test results, logistical and operational aspects, economical and ecological balances, chemical footprints of slurry designs are presented and discussed. The tested multifunctional additive can fully replace at least 4 different additives (extender, suspending agent, free fluid, fluid loss, and gas control additive) to achieve the desired performances and so simplify cement slurry designs. The multifunctional additive in this study also exhibits delayed hydration, which facilitates surface mixing and generates desired high viscosity over time, minimizing settling issues in horizontal wells during placement. The innovative cement design concept using a multifunctional additive reduce the number and loadings of chemical additives required to adjust the performance of cement slurries, thereby improving economics, reducing the chemical footprint, and simplifying logistics and operations.