摘要 |
The reaction product of a polyhydroxy compound and borax is used as a cement retarder for slurries introduced into a wellbore. The molar ratio of the polyhydroxy compound to boron, derived from the borax, is from 1:1 to about 4:1. The polyhydroxy compound may be a sugar such as a gluconic acid, gluconate or glucoheptonate or a salt thereof. |