Patent ID: 11208589

Abstract:
Described herein are methods for controlling or limiting the deposition of inorganic sulfide scale in wellbore operations. In some cases, method can include introducing a treatment fluid including a cationic polymeric quaternary amine or a polyethyleneimine polymer into a treatment area of a wellbore having metal cations, such as iron, zinc, and/or lead cations, and sulfide anions and contacting the metal cations and sulfide anions with the treatment fluid to reduce or prevent formation of metal sulfide particles in the treatment area. The polymers can include poly(methacrylamido-4,4,8,8-tetramethyl-4,8-diaza-6-hydroxylnonamethylene dichloride), poly(vinylbenzyl trimethyl ammonium chloride), polydimethyldiallyl ammonium chloride, or quaternized ammonium salt polyethyleneimine.