Abstract:
What is described herein is an aqueous high-temperature high-pressure (HTHP) stable drilling mud composition comprising (i) about 20 wt. % to about 80 wt. % of 0-60% w/w brine solution; (ii) about 0.1 wt. % to about 3 wt. % of butylated reaction product of p-cresol and dicyclopentadiene, a polymeric hindered phenol based antioxidant; (iii) about 0.1 wt. % to about 10.0 wt. % of triethanol amine, a chelating agent; (iv) (a) about 0.1 wt. % to about 10 wt. % of rheology modifier (RM); and/or (b) about 0.5 wt. % to about 30 wt. % of fluid loss additive (FLA); (v) about 20 wt. % to about 80 wt. % of weighting agent; (vi) about 0 wt. % to about 20 wt. % of drilling solid; and (vii) about 0 wt. % to about 50 wt % of water.
Abstract:
Stable water based High-Temperature-High-Pressure (HTHP) and/or Non-HTHP crosslinked copolymers for oil and gas applications consist of (i) a crosslinked, linear polyvinyl amide/polymerizable carboxylic acid) copolymer, having a composition, by weight, of 25-75 wt. % of a vinyl amide monomer selected from vinyl pyrrolidone, vinyl caprolactam, N-vinyl-N-methylacetamide and mixtures thereof, and 25-75 wt. % of a polymerizable carboxylic acid monomer selected from acrylic acid, (meth)acrylic acid, crotonic acid, itaconic acid, maleic acid and mixture thereof; and (ii) a crosslinker in an amount of 0.01-5% based on weight of total monomers. Also discloses relevant compositions comprising said copolymer and method of use thereof.
Abstract:
Disclosed herein is a water based High-Temperature High-Pressure (HTHP) fluid composition having a density of about 8.3 to about 21.0 ppg, comprising: (i) a brine based fluid; (ii) about 0.5 ppb to about 20 ppb of crosslinked polyvinylpyrrolidone (PVP); (iii) about 5 ppb to about 100 ppb of bridging agents selected from the group consisting of CaCO3 and sized salts; and (iv) optionally about 0 ppb to about 25 ppb of Fluids Loss Additives (FLA), wherein the crosslinked PVP is prepared by precipitation polymerization of vinylpyrrolidone (VP) in an organic solvent in the presence of a crosslinking agent and a free radical polymerization initiator, wherein the crosslinking agent is present in an amount of from about 0.1 wt. % to about 5.0 wt. % based on the weight of the vinylpyrrolidone. Also discloses a method of drilling and completing operations in a subterranean formation.