Laboratory Study of Viscoelastic Isolation Additive for Use in Oil Well Cementing

A new cementing additive, DQV, was prepared making the use of polymer's viscoelasticity. DQV is an additive used in cement slurry for better isolating formation and casing string. When mixed with cementing slurry, the mixture can render the annular space very good sealing, both efficient and flexible. Cement slurry treated with DQX had anti-migration capacity that was ten times of the original class G cement slurry, and the overall permeability of the set cement was reduced by two orders of magnitude. Meanwhile, the thickening time of the cement slurry was adjustable. The mobility and free water of the cement slurry were 25 cm and 0, respectively. Field application program for the cementing job using DQV was also studied for better anti-migration and isolation capacities of the cement slurry.