A method for controlling fluid loss in permeable formations

摘要

Controlling fluid loss in permeable formations penetrated by a wellbore comprises: (a) admixing an aqueous fluid containing enough polysaccharide polymer to viscosify the fluid, and enough crosslinking agent to create a gel structure in the fluid; (b) shearing the crosslinked gel so that it breaks into 10-80 mesh size particles (50% having mesh size less than 20 mesh); (c) slurrying the gel particles with an aqueous fluid to produce a suspension of particles; (d) introducing the suspension into the wellbore to contact the permeable formation; and (e) producing a filter cake of crosslinked gel on the face of the permeable formation to reduce fluid loss to the formation through the filter cake.