Methods of cementing in subterranean zones penetrated by well bores using biodegradable dispersants

摘要

The present invention provides methods of cementing subterranean zones penetrated by well bores using biodegradable dispersants. A cement composition of the invention comprises a hydraulic cement, sufficient water to form a slurry and a water soluble biodegradable cement dispersant comprising a polyamide graft copolymer containing at least o e side chain formed from aldehydes and sulfur-containing acids or their salts.