| 摘要 |
The invention is directed to methods for treating a portion of a well. The methods include the steps of: (A) forming a viscoelastic treatment fluid, wherein the treatment fluid comprises: (i) water; (ii) a viscoelastic surfactant (“VES”), wherein the VES is soluble in the water and wherein the VES is in the form of micelles; and (iii) a cross-linking agent for the VES molecules, wherein: (a) the cross-linking agent comprises cross-linking agent molecules having at least one complexed transition metal, wherein the transition metal has a valence state of at least three; and (b) the cross-linking agent is soluble in the water; and (B) introducing the treatment fluid into a portion of the well. According to a first aspect of the invention, (a) the VES comprises VES molecules having an alkyl group of greater than 14 carbon atoms and (b) the VES comprises VES molecules having at least one functional group selected from a carboxylate group, an amino group, an alcohol group, and an ether group. According to a second aspect of the invention, the VES comprises VES molecules having both an alkyl group of greater than 14 carbon atoms and at least one functional group selected from a carboxylate group, an amino group, an alcohol group, and an ether group. |
