Patent ID: 8869894

Claim:
A process of treating a subterranean formation such that thief zones or fractures are plugged in the subterranean formation at a substantial distance from a wellbore, the process comprising the steps of: introducing into the subterranean formation a sodium aluminate solution having a pH in a range of from 8 to 14 consisting essentially of NaAl(OH) 4 and a delayed crystallization additive; contacting the subterranean formation at a substantial distance from the wellbore with a supersaturated sodium aluminate solution having a pH in a range of from 8 to 14; and precipitating crystalline gibbsite onto a surface of the thief zones or fractures from the supersaturated sodium aluminate solution; where the sodium aluminate solution is operable to form gibbsite (Al(OH) 3 s ) within the subterranean formation while the sodium aluminate solution has a pH in a range of from 8 to 14 where the supersaturated sodium aluminate solution forms from the introduced sodium aluminate solution in the subterranean formation, and where the delayed crystallization additive is operable to delay crystallization of the gibbsite in the supersaturated sodium aluminate solution such that the thief zones or fractures are plugged with the crystalline gibbsite precipitated from the supersaturated sodium aluminate solution.